2005-04-16 22:20:36 +00:00
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#ifndef _LINUX_MM_H
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#define _LINUX_MM_H
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#include <linux/errno.h>
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#ifdef __KERNEL__
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2014-01-23 23:52:54 +00:00
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#include <linux/mmdebug.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/gfp.h>
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2011-11-24 01:12:59 +00:00
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#include <linux/bug.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/list.h>
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#include <linux/mmzone.h>
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#include <linux/rbtree.h>
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2011-12-08 22:33:54 +00:00
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#include <linux/atomic.h>
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2006-07-03 07:24:33 +00:00
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#include <linux/debug_locks.h>
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2006-09-27 08:50:01 +00:00
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#include <linux/mm_types.h>
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2010-02-10 09:20:20 +00:00
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#include <linux/range.h>
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2010-05-24 21:32:53 +00:00
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#include <linux/pfn.h>
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2011-01-13 23:46:32 +00:00
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#include <linux/bit_spinlock.h>
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2011-07-08 04:14:42 +00:00
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#include <linux/shrinker.h>
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2014-10-09 22:27:29 +00:00
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#include <linux/resource.h>
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mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
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#include <linux/page_ext.h>
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2005-04-16 22:20:36 +00:00
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struct mempolicy;
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struct anon_vma;
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mm anon rmap: replace same_anon_vma linked list with an interval tree.
When a large VMA (anon or private file mapping) is first touched, which
will populate its anon_vma field, and then split into many regions through
the use of mprotect(), the original anon_vma ends up linking all of the
vmas on a linked list. This can cause rmap to become inefficient, as we
have to walk potentially thousands of irrelevent vmas before finding the
one a given anon page might fall into.
By replacing the same_anon_vma linked list with an interval tree (where
each avc's interval is determined by its vma's start and last pgoffs), we
can make rmap efficient for this use case again.
While the change is large, all of its pieces are fairly simple.
Most places that were walking the same_anon_vma list were looking for a
known pgoff, so they can just use the anon_vma_interval_tree_foreach()
interval tree iterator instead. The exception here is ksm, where the
page's index is not known. It would probably be possible to rework ksm so
that the index would be known, but for now I have decided to keep things
simple and just walk the entirety of the interval tree there.
When updating vma's that already have an anon_vma assigned, we must take
care to re-index the corresponding avc's on their interval tree. This is
done through the use of anon_vma_interval_tree_pre_update_vma() and
anon_vma_interval_tree_post_update_vma(), which remove the avc's from
their interval tree before the update and re-insert them after the update.
The anon_vma stays locked during the update, so there is no chance that
rmap would miss the vmas that are being updated.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08 23:31:39 +00:00
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struct anon_vma_chain;
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2007-07-29 22:36:13 +00:00
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struct file_ra_state;
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Detach sched.h from mm.h
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-20 21:22:52 +00:00
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struct user_struct;
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2007-07-29 22:36:13 +00:00
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struct writeback_control;
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writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
The mechanism for detecting whether an inode should switch its wb
(bdi_writeback) association is now in place. This patch build the
framework for the actual switching.
This patch adds a new inode flag I_WB_SWITCHING, which has two
functions. First, the easy one, it ensures that there's only one
switching in progress for a give inode. Second, it's used as a
mechanism to synchronize wb stat updates.
The two stats, WB_RECLAIMABLE and WB_WRITEBACK, aren't event counters
but track the current number of dirty pages and pages under writeback
respectively. As such, when an inode is moved from one wb to another,
the inode's portion of those stats have to be transferred together;
unfortunately, this is a bit tricky as those stat updates are percpu
operations which are performed without holding any lock in some
places.
This patch solves the problem in a similar way as memcg. Each such
lockless stat updates are wrapped in transaction surrounded by
unlocked_inode_to_wb_begin/end(). During normal operation, they map
to rcu_read_lock/unlock(); however, if I_WB_SWITCHING is asserted,
mapping->tree_lock is grabbed across the transaction.
In turn, the switching path sets I_WB_SWITCHING and waits for a RCU
grace period to pass before actually starting to switch, which
guarantees that all stat update paths are synchronizing against
mapping->tree_lock.
This patch still doesn't implement the actual switching.
v3: Updated on top of the recent cancel_dirty_page() updates.
unlocked_inode_to_wb_begin() now nests inside
mem_cgroup_begin_page_stat() to match the locking order.
v2: The i_wb access transaction will be used for !stat accesses too.
Function names and comments updated accordingly.
s/inode_wb_stat_unlocked_{begin|end}/unlocked_inode_to_wb_{begin|end}/
s/switch_wb/switch_wbs/
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-28 18:50:53 +00:00
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struct bdi_writeback;
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2005-04-16 22:20:36 +00:00
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2013-07-03 22:04:23 +00:00
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#ifndef CONFIG_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */
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2005-04-16 22:20:36 +00:00
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extern unsigned long max_mapnr;
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2013-07-03 22:04:23 +00:00
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static inline void set_max_mapnr(unsigned long limit)
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{
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max_mapnr = limit;
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}
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#else
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static inline void set_max_mapnr(unsigned long limit) { }
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2005-04-16 22:20:36 +00:00
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#endif
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2009-09-22 00:03:05 +00:00
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extern unsigned long totalram_pages;
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2005-04-16 22:20:36 +00:00
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extern void * high_memory;
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extern int page_cluster;
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#ifdef CONFIG_SYSCTL
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extern int sysctl_legacy_va_layout;
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#else
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#define sysctl_legacy_va_layout 0
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#endif
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#include <asm/page.h>
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#include <asm/pgtable.h>
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#include <asm/processor.h>
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2013-11-12 23:07:59 +00:00
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#ifndef __pa_symbol
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#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
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#endif
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2014-10-23 10:07:44 +00:00
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/*
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* To prevent common memory management code establishing
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* a zero page mapping on a read fault.
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* This macro should be defined within <asm/pgtable.h>.
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* s390 does this to prevent multiplexing of hardware bits
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* related to the physical page in case of virtualization.
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*/
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#ifndef mm_forbids_zeropage
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#define mm_forbids_zeropage(X) (0)
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#endif
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mm: limit growth of 3% hardcoded other user reserve
Add user_reserve_kbytes knob.
Limit the growth of the memory reserved for other user processes to
min(3% current process size, user_reserve_pages). Only about 8MB is
necessary to enable recovery in the default mode, and only a few hundred
MB are required even when overcommit is disabled.
user_reserve_pages defaults to min(3% free pages, 128MB)
I arrived at 128MB by taking the max VSZ of sshd, login, bash, and top ...
then adding the RSS of each.
This only affects OVERCOMMIT_NEVER mode.
Background
1. user reserve
__vm_enough_memory reserves a hardcoded 3% of the current process size for
other applications when overcommit is disabled. This was done so that a
user could recover if they launched a memory hogging process. Without the
reserve, a user would easily run into a message such as:
bash: fork: Cannot allocate memory
2. admin reserve
Additionally, a hardcoded 3% of free memory is reserved for root in both
overcommit 'guess' and 'never' modes. This was intended to prevent a
scenario where root-cant-log-in and perform recovery operations.
Note that this reserve shrinks, and doesn't guarantee a useful reserve.
Motivation
The two hardcoded memory reserves should be updated to account for current
memory sizes.
Also, the admin reserve would be more useful if it didn't shrink too much.
When the current code was originally written, 1GB was considered
"enterprise". Now the 3% reserve can grow to multiple GB on large memory
systems, and it only needs to be a few hundred MB at most to enable a user
or admin to recover a system with an unwanted memory hogging process.
I've found that reducing these reserves is especially beneficial for a
specific type of application load:
* single application system
* one or few processes (e.g. one per core)
* allocating all available memory
* not initializing every page immediately
* long running
I've run scientific clusters with this sort of load. A long running job
sometimes failed many hours (weeks of CPU time) into a calculation. They
weren't initializing all of their memory immediately, and they weren't
using calloc, so I put systems into overcommit 'never' mode. These
clusters run diskless and have no swap.
However, with the current reserves, a user wishing to allocate as much
memory as possible to one process may be prevented from using, for
example, almost 2GB out of 32GB.
The effect is less, but still significant when a user starts a job with
one process per core. I have repeatedly seen a set of processes
requesting the same amount of memory fail because one of them could not
allocate the amount of memory a user would expect to be able to allocate.
For example, Message Passing Interfce (MPI) processes, one per core. And
it is similar for other parallel programming frameworks.
Changing this reserve code will make the overcommit never mode more useful
by allowing applications to allocate nearly all of the available memory.
Also, the new admin_reserve_kbytes will be safer than the current behavior
since the hardcoded 3% of available memory reserve can shrink to something
useless in the case where applications have grabbed all available memory.
Risks
* "bash: fork: Cannot allocate memory"
The downside of the first patch-- which creates a tunable user reserve
that is only used in overcommit 'never' mode--is that an admin can set
it so low that a user may not be able to kill their process, even if
they already have a shell prompt.
Of course, a user can get in the same predicament with the current 3%
reserve--they just have to launch processes until 3% becomes negligible.
* root-cant-log-in problem
The second patch, adding the tunable rootuser_reserve_pages, allows
the admin to shoot themselves in the foot by setting it too small. They
can easily get the system into a state where root-can't-log-in.
However, the new admin_reserve_kbytes will be safer than the current
behavior since the hardcoded 3% of available memory reserve can shrink
to something useless in the case where applications have grabbed all
available memory.
Alternatives
* Memory cgroups provide a more flexible way to limit application memory.
Not everyone wants to set up cgroups or deal with their overhead.
* We could create a fourth overcommit mode which provides smaller reserves.
The size of useful reserves may be drastically different depending
on the whether the system is embedded or enterprise.
* Force users to initialize all of their memory or use calloc.
Some users don't want/expect the system to overcommit when they malloc.
Overcommit 'never' mode is for this scenario, and it should work well.
The new user and admin reserve tunables are simple to use, with low
overhead compared to cgroups. The patches preserve current behavior where
3% of memory is less than 128MB, except that the admin reserve doesn't
shrink to an unusable size under pressure. The code allows admins to tune
for embedded and enterprise usage.
FAQ
* How is the root-cant-login problem addressed?
What happens if admin_reserve_pages is set to 0?
Root is free to shoot themselves in the foot by setting
admin_reserve_kbytes too low.
On x86_64, the minimum useful reserve is:
8MB for overcommit 'guess'
128MB for overcommit 'never'
admin_reserve_pages defaults to min(3% free memory, 8MB)
So, anyone switching to 'never' mode needs to adjust
admin_reserve_pages.
* How do you calculate a minimum useful reserve?
A user or the admin needs enough memory to login and perform
recovery operations, which includes, at a minimum:
sshd or login + bash (or some other shell) + top (or ps, kill, etc.)
For overcommit 'guess', we can sum resident set sizes (RSS)
because we only need enough memory to handle what the recovery
programs will typically use. On x86_64 this is about 8MB.
For overcommit 'never', we can take the max of their virtual sizes (VSZ)
and add the sum of their RSS. We use VSZ instead of RSS because mode
forces us to ensure we can fulfill all of the requested memory allocations--
even if the programs only use a fraction of what they ask for.
On x86_64 this is about 128MB.
When swap is enabled, reserves are useful even when they are as
small as 10MB, regardless of overcommit mode.
When both swap and overcommit are disabled, then the admin should
tune the reserves higher to be absolutley safe. Over 230MB each
was safest in my testing.
* What happens if user_reserve_pages is set to 0?
Note, this only affects overcomitt 'never' mode.
Then a user will be able to allocate all available memory minus
admin_reserve_kbytes.
However, they will easily see a message such as:
"bash: fork: Cannot allocate memory"
And they won't be able to recover/kill their application.
The admin should be able to recover the system if
admin_reserve_kbytes is set appropriately.
* What's the difference between overcommit 'guess' and 'never'?
"Guess" allows an allocation if there are enough free + reclaimable
pages. It has a hardcoded 3% of free pages reserved for root.
"Never" allows an allocation if there is enough swap + a configurable
percentage (default is 50) of physical RAM. It has a hardcoded 3% of
free pages reserved for root, like "Guess" mode. It also has a
hardcoded 3% of the current process size reserved for additional
applications.
* Why is overcommit 'guess' not suitable even when an app eventually
writes to every page? It takes free pages, file pages, available
swap pages, reclaimable slab pages into consideration. In other words,
these are all pages available, then why isn't overcommit suitable?
Because it only looks at the present state of the system. It
does not take into account the memory that other applications have
malloced, but haven't initialized yet. It overcommits the system.
Test Summary
There was little change in behavior in the default overcommit 'guess'
mode with swap enabled before and after the patch. This was expected.
Systems run most predictably (i.e. no oom kills) in overcommit 'never'
mode with swap enabled. This also allowed the most memory to be allocated
to a user application.
Overcommit 'guess' mode without swap is a bad idea. It is easy to
crash the system. None of the other tested combinations crashed.
This matches my experience on the Roadrunner supercomputer.
Without the tunable user reserve, a system in overcommit 'never' mode
and without swap does not allow the admin to recover, although the
admin can.
With the new tunable reserves, a system in overcommit 'never' mode
and without swap can be configured to:
1. maximize user-allocatable memory, running close to the edge of
recoverability
2. maximize recoverability, sacrificing allocatable memory to
ensure that a user cannot take down a system
Test Description
Fedora 18 VM - 4 x86_64 cores, 5725MB RAM, 4GB Swap
System is booted into multiuser console mode, with unnecessary services
turned off. Caches were dropped before each test.
Hogs are user memtester processes that attempt to allocate all free memory
as reported by /proc/meminfo
In overcommit 'never' mode, memory_ratio=100
Test Results
3.9.0-rc1-mm1
Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
---------- ---- ---- ------------- ---- ------------- --------------
guess yes 1 5432/5432 no yes yes
guess yes 4 5444/5444 1 yes yes
guess no 1 5302/5449 no yes yes
guess no 4 - crash no no
never yes 1 5460/5460 1 yes yes
never yes 4 5460/5460 1 yes yes
never no 1 5218/5432 no no yes
never no 4 5203/5448 no no yes
3.9.0-rc1-mm1-tunablereserves
User and Admin Recovery show their respective reserves, if applicable.
Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
---------- ---- ---- ------------- ---- ------------- --------------
guess yes 1 5419/5419 no - yes 8MB yes
guess yes 4 5436/5436 1 - yes 8MB yes
guess no 1 5440/5440 * - yes 8MB yes
guess no 4 - crash - no 8MB no
* process would successfully mlock, then the oom killer would pick it
never yes 1 5446/5446 no 10MB yes 20MB yes
never yes 4 5456/5456 no 10MB yes 20MB yes
never no 1 5387/5429 no 128MB no 8MB barely
never no 1 5323/5428 no 226MB barely 8MB barely
never no 1 5323/5428 no 226MB barely 8MB barely
never no 1 5359/5448 no 10MB no 10MB barely
never no 1 5323/5428 no 0MB no 10MB barely
never no 1 5332/5428 no 0MB no 50MB yes
never no 1 5293/5429 no 0MB no 90MB yes
never no 1 5001/5427 no 230MB yes 338MB yes
never no 4* 4998/5424 no 230MB yes 338MB yes
* more memtesters were launched, able to allocate approximately another 100MB
Future Work
- Test larger memory systems.
- Test an embedded image.
- Test other architectures.
- Time malloc microbenchmarks.
- Would it be useful to be able to set overcommit policy for
each memory cgroup?
- Some lines are slightly above 80 chars.
Perhaps define a macro to convert between pages and kb?
Other places in the kernel do this.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make init_user_reserve() static]
Signed-off-by: Andrew Shewmaker <agshew@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 22:08:10 +00:00
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extern unsigned long sysctl_user_reserve_kbytes;
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2013-04-29 22:08:11 +00:00
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extern unsigned long sysctl_admin_reserve_kbytes;
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mm: limit growth of 3% hardcoded other user reserve
Add user_reserve_kbytes knob.
Limit the growth of the memory reserved for other user processes to
min(3% current process size, user_reserve_pages). Only about 8MB is
necessary to enable recovery in the default mode, and only a few hundred
MB are required even when overcommit is disabled.
user_reserve_pages defaults to min(3% free pages, 128MB)
I arrived at 128MB by taking the max VSZ of sshd, login, bash, and top ...
then adding the RSS of each.
This only affects OVERCOMMIT_NEVER mode.
Background
1. user reserve
__vm_enough_memory reserves a hardcoded 3% of the current process size for
other applications when overcommit is disabled. This was done so that a
user could recover if they launched a memory hogging process. Without the
reserve, a user would easily run into a message such as:
bash: fork: Cannot allocate memory
2. admin reserve
Additionally, a hardcoded 3% of free memory is reserved for root in both
overcommit 'guess' and 'never' modes. This was intended to prevent a
scenario where root-cant-log-in and perform recovery operations.
Note that this reserve shrinks, and doesn't guarantee a useful reserve.
Motivation
The two hardcoded memory reserves should be updated to account for current
memory sizes.
Also, the admin reserve would be more useful if it didn't shrink too much.
When the current code was originally written, 1GB was considered
"enterprise". Now the 3% reserve can grow to multiple GB on large memory
systems, and it only needs to be a few hundred MB at most to enable a user
or admin to recover a system with an unwanted memory hogging process.
I've found that reducing these reserves is especially beneficial for a
specific type of application load:
* single application system
* one or few processes (e.g. one per core)
* allocating all available memory
* not initializing every page immediately
* long running
I've run scientific clusters with this sort of load. A long running job
sometimes failed many hours (weeks of CPU time) into a calculation. They
weren't initializing all of their memory immediately, and they weren't
using calloc, so I put systems into overcommit 'never' mode. These
clusters run diskless and have no swap.
However, with the current reserves, a user wishing to allocate as much
memory as possible to one process may be prevented from using, for
example, almost 2GB out of 32GB.
The effect is less, but still significant when a user starts a job with
one process per core. I have repeatedly seen a set of processes
requesting the same amount of memory fail because one of them could not
allocate the amount of memory a user would expect to be able to allocate.
For example, Message Passing Interfce (MPI) processes, one per core. And
it is similar for other parallel programming frameworks.
Changing this reserve code will make the overcommit never mode more useful
by allowing applications to allocate nearly all of the available memory.
Also, the new admin_reserve_kbytes will be safer than the current behavior
since the hardcoded 3% of available memory reserve can shrink to something
useless in the case where applications have grabbed all available memory.
Risks
* "bash: fork: Cannot allocate memory"
The downside of the first patch-- which creates a tunable user reserve
that is only used in overcommit 'never' mode--is that an admin can set
it so low that a user may not be able to kill their process, even if
they already have a shell prompt.
Of course, a user can get in the same predicament with the current 3%
reserve--they just have to launch processes until 3% becomes negligible.
* root-cant-log-in problem
The second patch, adding the tunable rootuser_reserve_pages, allows
the admin to shoot themselves in the foot by setting it too small. They
can easily get the system into a state where root-can't-log-in.
However, the new admin_reserve_kbytes will be safer than the current
behavior since the hardcoded 3% of available memory reserve can shrink
to something useless in the case where applications have grabbed all
available memory.
Alternatives
* Memory cgroups provide a more flexible way to limit application memory.
Not everyone wants to set up cgroups or deal with their overhead.
* We could create a fourth overcommit mode which provides smaller reserves.
The size of useful reserves may be drastically different depending
on the whether the system is embedded or enterprise.
* Force users to initialize all of their memory or use calloc.
Some users don't want/expect the system to overcommit when they malloc.
Overcommit 'never' mode is for this scenario, and it should work well.
The new user and admin reserve tunables are simple to use, with low
overhead compared to cgroups. The patches preserve current behavior where
3% of memory is less than 128MB, except that the admin reserve doesn't
shrink to an unusable size under pressure. The code allows admins to tune
for embedded and enterprise usage.
FAQ
* How is the root-cant-login problem addressed?
What happens if admin_reserve_pages is set to 0?
Root is free to shoot themselves in the foot by setting
admin_reserve_kbytes too low.
On x86_64, the minimum useful reserve is:
8MB for overcommit 'guess'
128MB for overcommit 'never'
admin_reserve_pages defaults to min(3% free memory, 8MB)
So, anyone switching to 'never' mode needs to adjust
admin_reserve_pages.
* How do you calculate a minimum useful reserve?
A user or the admin needs enough memory to login and perform
recovery operations, which includes, at a minimum:
sshd or login + bash (or some other shell) + top (or ps, kill, etc.)
For overcommit 'guess', we can sum resident set sizes (RSS)
because we only need enough memory to handle what the recovery
programs will typically use. On x86_64 this is about 8MB.
For overcommit 'never', we can take the max of their virtual sizes (VSZ)
and add the sum of their RSS. We use VSZ instead of RSS because mode
forces us to ensure we can fulfill all of the requested memory allocations--
even if the programs only use a fraction of what they ask for.
On x86_64 this is about 128MB.
When swap is enabled, reserves are useful even when they are as
small as 10MB, regardless of overcommit mode.
When both swap and overcommit are disabled, then the admin should
tune the reserves higher to be absolutley safe. Over 230MB each
was safest in my testing.
* What happens if user_reserve_pages is set to 0?
Note, this only affects overcomitt 'never' mode.
Then a user will be able to allocate all available memory minus
admin_reserve_kbytes.
However, they will easily see a message such as:
"bash: fork: Cannot allocate memory"
And they won't be able to recover/kill their application.
The admin should be able to recover the system if
admin_reserve_kbytes is set appropriately.
* What's the difference between overcommit 'guess' and 'never'?
"Guess" allows an allocation if there are enough free + reclaimable
pages. It has a hardcoded 3% of free pages reserved for root.
"Never" allows an allocation if there is enough swap + a configurable
percentage (default is 50) of physical RAM. It has a hardcoded 3% of
free pages reserved for root, like "Guess" mode. It also has a
hardcoded 3% of the current process size reserved for additional
applications.
* Why is overcommit 'guess' not suitable even when an app eventually
writes to every page? It takes free pages, file pages, available
swap pages, reclaimable slab pages into consideration. In other words,
these are all pages available, then why isn't overcommit suitable?
Because it only looks at the present state of the system. It
does not take into account the memory that other applications have
malloced, but haven't initialized yet. It overcommits the system.
Test Summary
There was little change in behavior in the default overcommit 'guess'
mode with swap enabled before and after the patch. This was expected.
Systems run most predictably (i.e. no oom kills) in overcommit 'never'
mode with swap enabled. This also allowed the most memory to be allocated
to a user application.
Overcommit 'guess' mode without swap is a bad idea. It is easy to
crash the system. None of the other tested combinations crashed.
This matches my experience on the Roadrunner supercomputer.
Without the tunable user reserve, a system in overcommit 'never' mode
and without swap does not allow the admin to recover, although the
admin can.
With the new tunable reserves, a system in overcommit 'never' mode
and without swap can be configured to:
1. maximize user-allocatable memory, running close to the edge of
recoverability
2. maximize recoverability, sacrificing allocatable memory to
ensure that a user cannot take down a system
Test Description
Fedora 18 VM - 4 x86_64 cores, 5725MB RAM, 4GB Swap
System is booted into multiuser console mode, with unnecessary services
turned off. Caches were dropped before each test.
Hogs are user memtester processes that attempt to allocate all free memory
as reported by /proc/meminfo
In overcommit 'never' mode, memory_ratio=100
Test Results
3.9.0-rc1-mm1
Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
---------- ---- ---- ------------- ---- ------------- --------------
guess yes 1 5432/5432 no yes yes
guess yes 4 5444/5444 1 yes yes
guess no 1 5302/5449 no yes yes
guess no 4 - crash no no
never yes 1 5460/5460 1 yes yes
never yes 4 5460/5460 1 yes yes
never no 1 5218/5432 no no yes
never no 4 5203/5448 no no yes
3.9.0-rc1-mm1-tunablereserves
User and Admin Recovery show their respective reserves, if applicable.
Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
---------- ---- ---- ------------- ---- ------------- --------------
guess yes 1 5419/5419 no - yes 8MB yes
guess yes 4 5436/5436 1 - yes 8MB yes
guess no 1 5440/5440 * - yes 8MB yes
guess no 4 - crash - no 8MB no
* process would successfully mlock, then the oom killer would pick it
never yes 1 5446/5446 no 10MB yes 20MB yes
never yes 4 5456/5456 no 10MB yes 20MB yes
never no 1 5387/5429 no 128MB no 8MB barely
never no 1 5323/5428 no 226MB barely 8MB barely
never no 1 5323/5428 no 226MB barely 8MB barely
never no 1 5359/5448 no 10MB no 10MB barely
never no 1 5323/5428 no 0MB no 10MB barely
never no 1 5332/5428 no 0MB no 50MB yes
never no 1 5293/5429 no 0MB no 90MB yes
never no 1 5001/5427 no 230MB yes 338MB yes
never no 4* 4998/5424 no 230MB yes 338MB yes
* more memtesters were launched, able to allocate approximately another 100MB
Future Work
- Test larger memory systems.
- Test an embedded image.
- Test other architectures.
- Time malloc microbenchmarks.
- Would it be useful to be able to set overcommit policy for
each memory cgroup?
- Some lines are slightly above 80 chars.
Perhaps define a macro to convert between pages and kb?
Other places in the kernel do this.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make init_user_reserve() static]
Signed-off-by: Andrew Shewmaker <agshew@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 22:08:10 +00:00
|
|
|
|
2014-01-21 23:49:14 +00:00
|
|
|
extern int sysctl_overcommit_memory;
|
|
|
|
extern int sysctl_overcommit_ratio;
|
|
|
|
extern unsigned long sysctl_overcommit_kbytes;
|
|
|
|
|
|
|
|
extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *,
|
|
|
|
size_t *, loff_t *);
|
|
|
|
extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
|
|
|
|
size_t *, loff_t *);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
|
|
|
|
|
2008-07-24 04:28:13 +00:00
|
|
|
/* to align the pointer to the (next) page boundary */
|
|
|
|
#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
|
|
|
|
|
2013-07-03 22:02:11 +00:00
|
|
|
/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
|
|
|
|
#define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE)
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* Linux kernel virtual memory manager primitives.
|
|
|
|
* The idea being to have a "virtual" mm in the same way
|
|
|
|
* we have a virtual fs - giving a cleaner interface to the
|
|
|
|
* mm details, and allowing different kinds of memory mappings
|
|
|
|
* (from shared memory to executable loading to arbitrary
|
|
|
|
* mmap() functions).
|
|
|
|
*/
|
|
|
|
|
2006-12-07 04:32:48 +00:00
|
|
|
extern struct kmem_cache *vm_area_cachep;
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#ifndef CONFIG_MMU
|
2009-01-08 12:04:47 +00:00
|
|
|
extern struct rb_root nommu_region_tree;
|
|
|
|
extern struct rw_semaphore nommu_region_sem;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
extern unsigned int kobjsize(const void *objp);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
2008-08-16 10:07:21 +00:00
|
|
|
* vm_flags in vm_area_struct, see mm_types.h.
|
2005-04-16 22:20:36 +00:00
|
|
|
*/
|
2012-10-08 23:28:37 +00:00
|
|
|
#define VM_NONE 0x00000000
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#define VM_READ 0x00000001 /* currently active flags */
|
|
|
|
#define VM_WRITE 0x00000002
|
|
|
|
#define VM_EXEC 0x00000004
|
|
|
|
#define VM_SHARED 0x00000008
|
|
|
|
|
2005-09-21 16:55:39 +00:00
|
|
|
/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
|
2005-04-16 22:20:36 +00:00
|
|
|
#define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
|
|
|
|
#define VM_MAYWRITE 0x00000020
|
|
|
|
#define VM_MAYEXEC 0x00000040
|
|
|
|
#define VM_MAYSHARE 0x00000080
|
|
|
|
|
|
|
|
#define VM_GROWSDOWN 0x00000100 /* general info on the segment */
|
2005-11-28 22:34:23 +00:00
|
|
|
#define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
|
2005-04-16 22:20:36 +00:00
|
|
|
#define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
|
|
|
|
|
|
|
|
#define VM_LOCKED 0x00002000
|
|
|
|
#define VM_IO 0x00004000 /* Memory mapped I/O or similar */
|
|
|
|
|
|
|
|
/* Used by sys_madvise() */
|
|
|
|
#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
|
|
|
|
#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
|
|
|
|
|
|
|
|
#define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
|
|
|
|
#define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
|
|
|
|
#define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */
|
2008-07-24 04:27:28 +00:00
|
|
|
#define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */
|
2005-04-16 22:20:36 +00:00
|
|
|
#define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
|
2012-10-08 23:28:37 +00:00
|
|
|
#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
|
x86, mpx: Introduce VM_MPX to indicate that a VMA is MPX specific
MPX-enabled applications using large swaths of memory can
potentially have large numbers of bounds tables in process
address space to save bounds information. These tables can take
up huge swaths of memory (as much as 80% of the memory on the
system) even if we clean them up aggressively. In the worst-case
scenario, the tables can be 4x the size of the data structure
being tracked. IOW, a 1-page structure can require 4 bounds-table
pages.
Being this huge, our expectation is that folks using MPX are
going to be keen on figuring out how much memory is being
dedicated to it. So we need a way to track memory use for MPX.
If we want to specifically track MPX VMAs we need to be able to
distinguish them from normal VMAs, and keep them from getting
merged with normal VMAs. A new VM_ flag set only on MPX VMAs does
both of those things. With this flag, MPX bounds-table VMAs can
be distinguished from other VMAs, and userspace can also walk
/proc/$pid/smaps to get memory usage for MPX.
In addition to this flag, we also introduce a special ->vm_ops
specific to MPX VMAs (see the patch "add MPX specific mmap
interface"), but currently different ->vm_ops do not by
themselves prevent VMA merging, so we still need this flag.
We understand that VM_ flags are scarce and are open to other
options.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151825.565625B3@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-14 15:18:25 +00:00
|
|
|
#define VM_ARCH_2 0x02000000
|
2012-10-08 23:28:59 +00:00
|
|
|
#define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */
|
mm: fix fault vs invalidate race for linear mappings
Fix the race between invalidate_inode_pages and do_no_page.
Andrea Arcangeli identified a subtle race between invalidation of pages from
pagecache with userspace mappings, and do_no_page.
The issue is that invalidation has to shoot down all mappings to the page,
before it can be discarded from the pagecache. Between shooting down ptes to
a particular page, and actually dropping the struct page from the pagecache,
do_no_page from any process might fault on that page and establish a new
mapping to the page just before it gets discarded from the pagecache.
The most common case where such invalidation is used is in file truncation.
This case was catered for by doing a sort of open-coded seqlock between the
file's i_size, and its truncate_count.
Truncation will decrease i_size, then increment truncate_count before
unmapping userspace pages; do_no_page will read truncate_count, then find the
page if it is within i_size, and then check truncate_count under the page
table lock and back out and retry if it had subsequently been changed (ptl
will serialise against unmapping, and ensure a potentially updated
truncate_count is actually visible).
Complexity and documentation issues aside, the locking protocol fails in the
case where we would like to invalidate pagecache inside i_size. do_no_page
can come in anytime and filemap_nopage is not aware of the invalidation in
progress (as it is when it is outside i_size). The end result is that
dangling (->mapping == NULL) pages that appear to be from a particular file
may be mapped into userspace with nonsense data. Valid mappings to the same
place will see a different page.
Andrea implemented two working fixes, one using a real seqlock, another using
a page->flags bit. He also proposed using the page lock in do_no_page, but
that was initially considered too heavyweight. However, it is not a global or
per-file lock, and the page cacheline is modified in do_no_page to increment
_count and _mapcount anyway, so a further modification should not be a large
performance hit. Scalability is not an issue.
This patch implements this latter approach. ->nopage implementations return
with the page locked if it is possible for their underlying file to be
invalidated (in that case, they must set a special vm_flags bit to indicate
so). do_no_page only unlocks the page after setting up the mapping
completely. invalidation is excluded because it holds the page lock during
invalidation of each page (and ensures that the page is not mapped while
holding the lock).
This also allows significant simplifications in do_no_page, because we have
the page locked in the right place in the pagecache from the start.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:57 +00:00
|
|
|
|
2013-09-11 21:22:24 +00:00
|
|
|
#ifdef CONFIG_MEM_SOFT_DIRTY
|
|
|
|
# define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */
|
|
|
|
#else
|
|
|
|
# define VM_SOFTDIRTY 0
|
|
|
|
#endif
|
|
|
|
|
mm: introduce VM_MIXEDMAP
This series introduces some important infrastructure work. The overall result
is that:
1. We now support XIP backed filesystems using memory that have no
struct page allocated to them. And patches 6 and 7 actually implement
this for s390.
This is pretty important in a number of cases. As far as I understand,
in the case of virtualisation (eg. s390), each guest may mount a
readonly copy of the same filesystem (eg. the distro). Currently,
guests need to allocate struct pages for this image. So if you have
100 guests, you already need to allocate more memory for the struct
pages than the size of the image. I think. (Carsten?)
For other (eg. embedded) systems, you may have a very large non-
volatile filesystem. If you have to have struct pages for this, then
your RAM consumption will go up proportionally to fs size. Even
though it is just a small proportion, the RAM can be much more costly
eg in terms of power, so every KB less that Linux uses makes it more
attractive to a lot of these guys.
2. VM_MIXEDMAP allows us to support mappings where you actually do want
to refcount _some_ pages in the mapping, but not others, and support
COW on arbitrary (non-linear) mappings. Jared needs this for his NVRAM
filesystem in progress. Future iterations of this filesystem will
most likely want to migrate pages between pagecache and XIP backing,
which is where the requirement for mixed (some refcounted, some not)
comes from.
3. pte_special also has a peripheral usage that I need for my lockless
get_user_pages patch. That was shown to speed up "oltp" on db2 by
10% on a 2 socket system, which is kind of significant because they
scrounge for months to try to find 0.1% improvement on these
workloads. I'm hoping we might finally be faster than AIX on
pSeries with this :). My reference to lockless get_user_pages is not
meant to justify this patchset (which doesn't include lockless gup),
but just to show that pte_special is not some s390 specific thing that
should be hidden in arch code or xip code: I definitely want to use it
on at least x86 and powerpc as well.
This patch:
Introduce a new type of mapping, VM_MIXEDMAP. This is unlike VM_PFNMAP in
that it can support COW mappings of arbitrary ranges including ranges without
struct page *and* ranges with a struct page that we actually want to refcount
(PFNMAP can only support COW in those cases where the un-COW-ed translations
are mapped linearly in the virtual address, and can only support non
refcounted ranges).
VM_MIXEDMAP achieves this by refcounting all pfn_valid pages, and not
refcounting !pfn_valid pages (which is not an option for VM_PFNMAP, because it
needs to avoid refcounting pfn_valid pages eg. for /dev/mem mappings).
Signed-off-by: Jared Hulbert <jaredeh@gmail.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:12:58 +00:00
|
|
|
#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
|
2012-10-08 23:28:37 +00:00
|
|
|
#define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
|
|
|
|
#define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
|
2009-09-22 00:01:57 +00:00
|
|
|
#define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2012-10-08 23:28:37 +00:00
|
|
|
#if defined(CONFIG_X86)
|
|
|
|
# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
|
|
|
|
#elif defined(CONFIG_PPC)
|
|
|
|
# define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
|
|
|
|
#elif defined(CONFIG_PARISC)
|
|
|
|
# define VM_GROWSUP VM_ARCH_1
|
2012-10-16 09:16:14 +00:00
|
|
|
#elif defined(CONFIG_METAG)
|
|
|
|
# define VM_GROWSUP VM_ARCH_1
|
2012-10-08 23:28:37 +00:00
|
|
|
#elif defined(CONFIG_IA64)
|
|
|
|
# define VM_GROWSUP VM_ARCH_1
|
|
|
|
#elif !defined(CONFIG_MMU)
|
|
|
|
# define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
|
|
|
|
#endif
|
|
|
|
|
x86, mpx: Introduce VM_MPX to indicate that a VMA is MPX specific
MPX-enabled applications using large swaths of memory can
potentially have large numbers of bounds tables in process
address space to save bounds information. These tables can take
up huge swaths of memory (as much as 80% of the memory on the
system) even if we clean them up aggressively. In the worst-case
scenario, the tables can be 4x the size of the data structure
being tracked. IOW, a 1-page structure can require 4 bounds-table
pages.
Being this huge, our expectation is that folks using MPX are
going to be keen on figuring out how much memory is being
dedicated to it. So we need a way to track memory use for MPX.
If we want to specifically track MPX VMAs we need to be able to
distinguish them from normal VMAs, and keep them from getting
merged with normal VMAs. A new VM_ flag set only on MPX VMAs does
both of those things. With this flag, MPX bounds-table VMAs can
be distinguished from other VMAs, and userspace can also walk
/proc/$pid/smaps to get memory usage for MPX.
In addition to this flag, we also introduce a special ->vm_ops
specific to MPX VMAs (see the patch "add MPX specific mmap
interface"), but currently different ->vm_ops do not by
themselves prevent VMA merging, so we still need this flag.
We understand that VM_ flags are scarce and are open to other
options.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151825.565625B3@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-14 15:18:25 +00:00
|
|
|
#if defined(CONFIG_X86)
|
|
|
|
/* MPX specific bounds table or bounds directory */
|
|
|
|
# define VM_MPX VM_ARCH_2
|
|
|
|
#endif
|
|
|
|
|
2012-10-08 23:28:37 +00:00
|
|
|
#ifndef VM_GROWSUP
|
|
|
|
# define VM_GROWSUP VM_NONE
|
|
|
|
#endif
|
|
|
|
|
2010-05-24 21:32:24 +00:00
|
|
|
/* Bits set in the VMA until the stack is in its final location */
|
|
|
|
#define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
|
|
|
|
#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_STACK_GROWSUP
|
|
|
|
#define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
|
|
|
|
#else
|
|
|
|
#define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
|
|
|
|
#endif
|
|
|
|
|
mlock: mlocked pages are unevictable
Make sure that mlocked pages also live on the unevictable LRU, so kswapd
will not scan them over and over again.
This is achieved through various strategies:
1) add yet another page flag--PG_mlocked--to indicate that
the page is locked for efficient testing in vmscan and,
optionally, fault path. This allows early culling of
unevictable pages, preventing them from getting to
page_referenced()/try_to_unmap(). Also allows separate
accounting of mlock'd pages, as Nick's original patch
did.
Note: Nick's original mlock patch used a PG_mlocked
flag. I had removed this in favor of the PG_unevictable
flag + an mlock_count [new page struct member]. I
restored the PG_mlocked flag to eliminate the new
count field.
2) add the mlock/unevictable infrastructure to mm/mlock.c,
with internal APIs in mm/internal.h. This is a rework
of Nick's original patch to these files, taking into
account that mlocked pages are now kept on unevictable
LRU list.
3) update vmscan.c:page_evictable() to check PageMlocked()
and, if vma passed in, the vm_flags. Note that the vma
will only be passed in for new pages in the fault path;
and then only if the "cull unevictable pages in fault
path" patch is included.
4) add try_to_unlock() to rmap.c to walk a page's rmap and
ClearPageMlocked() if no other vmas have it mlocked.
Reuses as much of try_to_unmap() as possible. This
effectively replaces the use of one of the lru list links
as an mlock count. If this mechanism let's pages in mlocked
vmas leak through w/o PG_mlocked set [I don't know that it
does], we should catch them later in try_to_unmap(). One
hopes this will be rare, as it will be relatively expensive.
Original mm/internal.h, mm/rmap.c and mm/mlock.c changes:
Signed-off-by: Nick Piggin <npiggin@suse.de>
splitlru: introduce __get_user_pages():
New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS.
because current get_user_pages() can't grab PROT_NONE pages theresore it
cause PROT_NONE pages can't munlock.
[akpm@linux-foundation.org: fix this for pagemap-pass-mm-into-pagewalkers.patch]
[akpm@linux-foundation.org: untangle patch interdependencies]
[akpm@linux-foundation.org: fix things after out-of-order merging]
[hugh@veritas.com: fix page-flags mess]
[lee.schermerhorn@hp.com: fix munlock page table walk - now requires 'mm']
[kosaki.motohiro@jp.fujitsu.com: build fix]
[kosaki.motohiro@jp.fujitsu.com: fix truncate race and sevaral comments]
[kosaki.motohiro@jp.fujitsu.com: splitlru: introduce __get_user_pages()]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-19 03:26:44 +00:00
|
|
|
/*
|
2011-04-27 22:26:45 +00:00
|
|
|
* Special vmas that are non-mergable, non-mlock()able.
|
|
|
|
* Note: mm/huge_memory.c VM_NO_THP depends on this definition.
|
mlock: mlocked pages are unevictable
Make sure that mlocked pages also live on the unevictable LRU, so kswapd
will not scan them over and over again.
This is achieved through various strategies:
1) add yet another page flag--PG_mlocked--to indicate that
the page is locked for efficient testing in vmscan and,
optionally, fault path. This allows early culling of
unevictable pages, preventing them from getting to
page_referenced()/try_to_unmap(). Also allows separate
accounting of mlock'd pages, as Nick's original patch
did.
Note: Nick's original mlock patch used a PG_mlocked
flag. I had removed this in favor of the PG_unevictable
flag + an mlock_count [new page struct member]. I
restored the PG_mlocked flag to eliminate the new
count field.
2) add the mlock/unevictable infrastructure to mm/mlock.c,
with internal APIs in mm/internal.h. This is a rework
of Nick's original patch to these files, taking into
account that mlocked pages are now kept on unevictable
LRU list.
3) update vmscan.c:page_evictable() to check PageMlocked()
and, if vma passed in, the vm_flags. Note that the vma
will only be passed in for new pages in the fault path;
and then only if the "cull unevictable pages in fault
path" patch is included.
4) add try_to_unlock() to rmap.c to walk a page's rmap and
ClearPageMlocked() if no other vmas have it mlocked.
Reuses as much of try_to_unmap() as possible. This
effectively replaces the use of one of the lru list links
as an mlock count. If this mechanism let's pages in mlocked
vmas leak through w/o PG_mlocked set [I don't know that it
does], we should catch them later in try_to_unmap(). One
hopes this will be rare, as it will be relatively expensive.
Original mm/internal.h, mm/rmap.c and mm/mlock.c changes:
Signed-off-by: Nick Piggin <npiggin@suse.de>
splitlru: introduce __get_user_pages():
New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS.
because current get_user_pages() can't grab PROT_NONE pages theresore it
cause PROT_NONE pages can't munlock.
[akpm@linux-foundation.org: fix this for pagemap-pass-mm-into-pagewalkers.patch]
[akpm@linux-foundation.org: untangle patch interdependencies]
[akpm@linux-foundation.org: fix things after out-of-order merging]
[hugh@veritas.com: fix page-flags mess]
[lee.schermerhorn@hp.com: fix munlock page table walk - now requires 'mm']
[kosaki.motohiro@jp.fujitsu.com: build fix]
[kosaki.motohiro@jp.fujitsu.com: fix truncate race and sevaral comments]
[kosaki.motohiro@jp.fujitsu.com: splitlru: introduce __get_user_pages()]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-19 03:26:44 +00:00
|
|
|
*/
|
2014-03-03 23:38:27 +00:00
|
|
|
#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
|
mlock: mlocked pages are unevictable
Make sure that mlocked pages also live on the unevictable LRU, so kswapd
will not scan them over and over again.
This is achieved through various strategies:
1) add yet another page flag--PG_mlocked--to indicate that
the page is locked for efficient testing in vmscan and,
optionally, fault path. This allows early culling of
unevictable pages, preventing them from getting to
page_referenced()/try_to_unmap(). Also allows separate
accounting of mlock'd pages, as Nick's original patch
did.
Note: Nick's original mlock patch used a PG_mlocked
flag. I had removed this in favor of the PG_unevictable
flag + an mlock_count [new page struct member]. I
restored the PG_mlocked flag to eliminate the new
count field.
2) add the mlock/unevictable infrastructure to mm/mlock.c,
with internal APIs in mm/internal.h. This is a rework
of Nick's original patch to these files, taking into
account that mlocked pages are now kept on unevictable
LRU list.
3) update vmscan.c:page_evictable() to check PageMlocked()
and, if vma passed in, the vm_flags. Note that the vma
will only be passed in for new pages in the fault path;
and then only if the "cull unevictable pages in fault
path" patch is included.
4) add try_to_unlock() to rmap.c to walk a page's rmap and
ClearPageMlocked() if no other vmas have it mlocked.
Reuses as much of try_to_unmap() as possible. This
effectively replaces the use of one of the lru list links
as an mlock count. If this mechanism let's pages in mlocked
vmas leak through w/o PG_mlocked set [I don't know that it
does], we should catch them later in try_to_unmap(). One
hopes this will be rare, as it will be relatively expensive.
Original mm/internal.h, mm/rmap.c and mm/mlock.c changes:
Signed-off-by: Nick Piggin <npiggin@suse.de>
splitlru: introduce __get_user_pages():
New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS.
because current get_user_pages() can't grab PROT_NONE pages theresore it
cause PROT_NONE pages can't munlock.
[akpm@linux-foundation.org: fix this for pagemap-pass-mm-into-pagewalkers.patch]
[akpm@linux-foundation.org: untangle patch interdependencies]
[akpm@linux-foundation.org: fix things after out-of-order merging]
[hugh@veritas.com: fix page-flags mess]
[lee.schermerhorn@hp.com: fix munlock page table walk - now requires 'mm']
[kosaki.motohiro@jp.fujitsu.com: build fix]
[kosaki.motohiro@jp.fujitsu.com: fix truncate race and sevaral comments]
[kosaki.motohiro@jp.fujitsu.com: splitlru: introduce __get_user_pages()]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-19 03:26:44 +00:00
|
|
|
|
2014-04-07 22:37:10 +00:00
|
|
|
/* This mask defines which mm->def_flags a process can inherit its parent */
|
|
|
|
#define VM_INIT_DEF_MASK VM_NOHUGEPAGE
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* mapping from the currently active vm_flags protection bits (the
|
|
|
|
* low four bits) to a page protection mask..
|
|
|
|
*/
|
|
|
|
extern pgprot_t protection_map[16];
|
|
|
|
|
2007-07-19 08:47:03 +00:00
|
|
|
#define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */
|
2015-02-10 22:09:51 +00:00
|
|
|
#define FAULT_FLAG_MKWRITE 0x02 /* Fault was mkwrite of existing pte */
|
|
|
|
#define FAULT_FLAG_ALLOW_RETRY 0x04 /* Retry fault if blocking */
|
|
|
|
#define FAULT_FLAG_RETRY_NOWAIT 0x08 /* Don't drop mmap_sem and wait when retrying */
|
|
|
|
#define FAULT_FLAG_KILLABLE 0x10 /* The fault task is in SIGKILL killable region */
|
|
|
|
#define FAULT_FLAG_TRIED 0x20 /* Second try */
|
|
|
|
#define FAULT_FLAG_USER 0x40 /* The fault originated in userspace */
|
2007-07-19 08:47:03 +00:00
|
|
|
|
2007-07-19 08:46:59 +00:00
|
|
|
/*
|
2007-07-19 08:47:03 +00:00
|
|
|
* vm_fault is filled by the the pagefault handler and passed to the vma's
|
2007-07-19 08:47:05 +00:00
|
|
|
* ->fault function. The vma's ->fault is responsible for returning a bitmask
|
|
|
|
* of VM_FAULT_xxx flags that give details about how the fault was handled.
|
2007-07-19 08:46:59 +00:00
|
|
|
*
|
2015-02-10 22:09:51 +00:00
|
|
|
* pgoff should be used in favour of virtual_address, if possible.
|
2007-07-19 08:46:59 +00:00
|
|
|
*/
|
2007-07-19 08:47:03 +00:00
|
|
|
struct vm_fault {
|
|
|
|
unsigned int flags; /* FAULT_FLAG_xxx flags */
|
|
|
|
pgoff_t pgoff; /* Logical page offset based on vma */
|
|
|
|
void __user *virtual_address; /* Faulting virtual address */
|
|
|
|
|
2015-02-16 23:58:50 +00:00
|
|
|
struct page *cow_page; /* Handler may choose to COW */
|
2007-07-19 08:47:03 +00:00
|
|
|
struct page *page; /* ->fault handlers should return a
|
2007-07-19 08:47:05 +00:00
|
|
|
* page here, unless VM_FAULT_NOPAGE
|
2007-07-19 08:47:03 +00:00
|
|
|
* is set (which is also implied by
|
2007-07-19 08:47:05 +00:00
|
|
|
* VM_FAULT_ERROR).
|
2007-07-19 08:47:03 +00:00
|
|
|
*/
|
mm: introduce vm_ops->map_pages()
Here's new version of faultaround patchset. It took a while to tune it
and collect performance data.
First patch adds new callback ->map_pages to vm_operations_struct.
->map_pages() is called when VM asks to map easy accessible pages.
Filesystem should find and map pages associated with offsets from
"pgoff" till "max_pgoff". ->map_pages() is called with page table
locked and must not block. If it's not possible to reach a page without
blocking, filesystem should skip it. Filesystem should use do_set_pte()
to setup page table entry. Pointer to entry associated with offset
"pgoff" is passed in "pte" field in vm_fault structure. Pointers to
entries for other offsets should be calculated relative to "pte".
Currently VM use ->map_pages only on read page fault path. We try to
map FAULT_AROUND_PAGES a time. FAULT_AROUND_PAGES is 16 for now.
Performance data for different FAULT_AROUND_ORDER is below.
TODO:
- implement ->map_pages() for shmem/tmpfs;
- modify get_user_pages() to be able to use ->map_pages() and implement
mmap(MAP_POPULATE|MAP_NONBLOCK) on top.
=========================================================================
Tested on 4-socket machine (120 threads) with 128GiB of RAM.
Few real-world workloads. The sweet spot for FAULT_AROUND_ORDER here is
somewhere between 3 and 5. Let's say 4 :)
Linux build (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 283,301,572 247,151,987 212,215,789 204,772,882 199,568,944 194,703,779 193,381,485
time, seconds 151.227629483 153.920996480 151.356125472 150.863792049 150.879207877 151.150764954 151.450962358
Linux rebuild (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 5,396,854 4,148,444 2,855,286 2,577,282 2,361,957 2,169,573 2,112,643
time, seconds 27.404543757 27.559725591 27.030057426 26.855045126 26.678618635 26.974523490 26.761320095
Git test suite (make -j60 test)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 129,591,823 99,200,751 66,106,718 57,606,410 51,510,808 45,776,813 44,085,515
time, seconds 66.087215026 64.784546905 64.401156567 65.282708668 66.034016829 66.793780811 67.237810413
Two synthetic tests: access every word in file in sequential/random order.
It doesn't improve much after FAULT_AROUND_ORDER == 4.
Sequential access 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 4,195,437 2,098,275 525,068 262,251 131,170 32,856 8,282
time, seconds 7.250461742 6.461711074 5.493859139 5.488488147 5.707213983 5.898510832 5.109232856
8 threads
minor-faults 33,557,540 16,892,728 4,515,848 2,366,999 1,423,382 442,732 142,339
time, seconds 16.649304881 9.312555263 6.612490639 6.394316732 6.669827501 6.75078944 6.371900528
32 threads
minor-faults 134,228,222 67,526,810 17,725,386 9,716,537 4,763,731 1,668,921 537,200
time, seconds 49.164430543 29.712060103 12.938649729 10.175151004 11.840094583 9.594081325 9.928461797
60 threads
minor-faults 251,687,988 126,146,952 32,919,406 18,208,804 10,458,947 2,733,907 928,217
time, seconds 86.260656897 49.626551828 22.335007632 17.608243696 16.523119035 16.339489186 16.326390902
120 threads
minor-faults 503,352,863 252,939,677 67,039,168 35,191,827 19,170,091 4,688,357 1,471,862
time, seconds 124.589206333 79.757867787 39.508707872 32.167281632 29.972989292 28.729834575 28.042251622
Random access 1GiB file
1 thread
minor-faults 262,636 132,743 34,369 17,299 8,527 3,451 1,222
time, seconds 15.351890914 16.613802482 16.569227308 15.179220992 16.557356122 16.578247824 15.365266994
8 threads
minor-faults 2,098,948 1,061,871 273,690 154,501 87,110 25,663 7,384
time, seconds 15.040026343 15.096933500 14.474757288 14.289129964 14.411537468 14.296316837 14.395635804
32 threads
minor-faults 8,390,734 4,231,023 1,054,432 528,847 269,242 97,746 26,881
time, seconds 20.430433109 21.585235358 22.115062928 14.872878951 14.880856305 14.883370649 14.821261690
60 threads
minor-faults 15,733,258 7,892,809 1,973,393 988,266 594,789 164,994 51,691
time, seconds 26.577302548 25.692397770 18.728863715 20.153026398 21.619101933 17.745086260 17.613215273
120 threads
minor-faults 31,471,111 15,816,616 3,959,209 1,978,685 1,008,299 264,635 96,010
time, seconds 41.835322703 40.459786095 36.085306105 35.313894834 35.814445675 36.552633793 34.289210594
Touch only one page in page table in 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 8,372 8,324 8,270 8,260 8,249 8,239 8,237
time, seconds 0.039892712 0.045369149 0.051846126 0.063681685 0.079095975 0.17652406 0.541213386
8 threads
minor-faults 65,731 65,681 65,628 65,620 65,608 65,599 65,596
time, seconds 0.124159196 0.488600638 0.156854426 0.191901957 0.242631486 0.543569456 1.677303984
32 threads
minor-faults 262,388 262,341 262,285 262,276 262,266 262,257 263,183
time, seconds 0.452421421 0.488600638 0.565020946 0.648229739 0.789850823 1.651584361 5.000361559
60 threads
minor-faults 491,822 491,792 491,723 491,711 491,701 491,691 491,825
time, seconds 0.763288616 0.869620515 0.980727360 1.161732354 1.466915814 3.04041448 9.308612938
120 threads
minor-faults 983,466 983,655 983,366 983,372 983,363 984,083 984,164
time, seconds 1.595846553 1.667902182 2.008959376 2.425380942 2.941368804 5.977807890 18.401846125
This patch (of 2):
Introduce new vm_ops callback ->map_pages() and uses it for mapping easy
accessible pages around fault address.
On read page fault, if filesystem provides ->map_pages(), we try to map up
to FAULT_AROUND_PAGES pages around page fault address in hope to reduce
number of minor page faults.
We call ->map_pages first and use ->fault() as fallback if page by the
offset is not ready to be mapped (cold page cache or something).
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 22:37:18 +00:00
|
|
|
/* for ->map_pages() only */
|
|
|
|
pgoff_t max_pgoff; /* map pages for offset from pgoff till
|
|
|
|
* max_pgoff inclusive */
|
|
|
|
pte_t *pte; /* pte entry associated with ->pgoff */
|
2007-07-19 08:46:59 +00:00
|
|
|
};
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* These are the virtual MM functions - opening of an area, closing and
|
|
|
|
* unmapping it (needed to keep files on disk up-to-date etc), pointer
|
|
|
|
* to the functions called when a no-page or a wp-page exception occurs.
|
|
|
|
*/
|
|
|
|
struct vm_operations_struct {
|
|
|
|
void (*open)(struct vm_area_struct * area);
|
|
|
|
void (*close)(struct vm_area_struct * area);
|
2007-07-19 08:47:03 +00:00
|
|
|
int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
|
mm: introduce vm_ops->map_pages()
Here's new version of faultaround patchset. It took a while to tune it
and collect performance data.
First patch adds new callback ->map_pages to vm_operations_struct.
->map_pages() is called when VM asks to map easy accessible pages.
Filesystem should find and map pages associated with offsets from
"pgoff" till "max_pgoff". ->map_pages() is called with page table
locked and must not block. If it's not possible to reach a page without
blocking, filesystem should skip it. Filesystem should use do_set_pte()
to setup page table entry. Pointer to entry associated with offset
"pgoff" is passed in "pte" field in vm_fault structure. Pointers to
entries for other offsets should be calculated relative to "pte".
Currently VM use ->map_pages only on read page fault path. We try to
map FAULT_AROUND_PAGES a time. FAULT_AROUND_PAGES is 16 for now.
Performance data for different FAULT_AROUND_ORDER is below.
TODO:
- implement ->map_pages() for shmem/tmpfs;
- modify get_user_pages() to be able to use ->map_pages() and implement
mmap(MAP_POPULATE|MAP_NONBLOCK) on top.
=========================================================================
Tested on 4-socket machine (120 threads) with 128GiB of RAM.
Few real-world workloads. The sweet spot for FAULT_AROUND_ORDER here is
somewhere between 3 and 5. Let's say 4 :)
Linux build (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 283,301,572 247,151,987 212,215,789 204,772,882 199,568,944 194,703,779 193,381,485
time, seconds 151.227629483 153.920996480 151.356125472 150.863792049 150.879207877 151.150764954 151.450962358
Linux rebuild (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 5,396,854 4,148,444 2,855,286 2,577,282 2,361,957 2,169,573 2,112,643
time, seconds 27.404543757 27.559725591 27.030057426 26.855045126 26.678618635 26.974523490 26.761320095
Git test suite (make -j60 test)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 129,591,823 99,200,751 66,106,718 57,606,410 51,510,808 45,776,813 44,085,515
time, seconds 66.087215026 64.784546905 64.401156567 65.282708668 66.034016829 66.793780811 67.237810413
Two synthetic tests: access every word in file in sequential/random order.
It doesn't improve much after FAULT_AROUND_ORDER == 4.
Sequential access 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 4,195,437 2,098,275 525,068 262,251 131,170 32,856 8,282
time, seconds 7.250461742 6.461711074 5.493859139 5.488488147 5.707213983 5.898510832 5.109232856
8 threads
minor-faults 33,557,540 16,892,728 4,515,848 2,366,999 1,423,382 442,732 142,339
time, seconds 16.649304881 9.312555263 6.612490639 6.394316732 6.669827501 6.75078944 6.371900528
32 threads
minor-faults 134,228,222 67,526,810 17,725,386 9,716,537 4,763,731 1,668,921 537,200
time, seconds 49.164430543 29.712060103 12.938649729 10.175151004 11.840094583 9.594081325 9.928461797
60 threads
minor-faults 251,687,988 126,146,952 32,919,406 18,208,804 10,458,947 2,733,907 928,217
time, seconds 86.260656897 49.626551828 22.335007632 17.608243696 16.523119035 16.339489186 16.326390902
120 threads
minor-faults 503,352,863 252,939,677 67,039,168 35,191,827 19,170,091 4,688,357 1,471,862
time, seconds 124.589206333 79.757867787 39.508707872 32.167281632 29.972989292 28.729834575 28.042251622
Random access 1GiB file
1 thread
minor-faults 262,636 132,743 34,369 17,299 8,527 3,451 1,222
time, seconds 15.351890914 16.613802482 16.569227308 15.179220992 16.557356122 16.578247824 15.365266994
8 threads
minor-faults 2,098,948 1,061,871 273,690 154,501 87,110 25,663 7,384
time, seconds 15.040026343 15.096933500 14.474757288 14.289129964 14.411537468 14.296316837 14.395635804
32 threads
minor-faults 8,390,734 4,231,023 1,054,432 528,847 269,242 97,746 26,881
time, seconds 20.430433109 21.585235358 22.115062928 14.872878951 14.880856305 14.883370649 14.821261690
60 threads
minor-faults 15,733,258 7,892,809 1,973,393 988,266 594,789 164,994 51,691
time, seconds 26.577302548 25.692397770 18.728863715 20.153026398 21.619101933 17.745086260 17.613215273
120 threads
minor-faults 31,471,111 15,816,616 3,959,209 1,978,685 1,008,299 264,635 96,010
time, seconds 41.835322703 40.459786095 36.085306105 35.313894834 35.814445675 36.552633793 34.289210594
Touch only one page in page table in 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 8,372 8,324 8,270 8,260 8,249 8,239 8,237
time, seconds 0.039892712 0.045369149 0.051846126 0.063681685 0.079095975 0.17652406 0.541213386
8 threads
minor-faults 65,731 65,681 65,628 65,620 65,608 65,599 65,596
time, seconds 0.124159196 0.488600638 0.156854426 0.191901957 0.242631486 0.543569456 1.677303984
32 threads
minor-faults 262,388 262,341 262,285 262,276 262,266 262,257 263,183
time, seconds 0.452421421 0.488600638 0.565020946 0.648229739 0.789850823 1.651584361 5.000361559
60 threads
minor-faults 491,822 491,792 491,723 491,711 491,701 491,691 491,825
time, seconds 0.763288616 0.869620515 0.980727360 1.161732354 1.466915814 3.04041448 9.308612938
120 threads
minor-faults 983,466 983,655 983,366 983,372 983,363 984,083 984,164
time, seconds 1.595846553 1.667902182 2.008959376 2.425380942 2.941368804 5.977807890 18.401846125
This patch (of 2):
Introduce new vm_ops callback ->map_pages() and uses it for mapping easy
accessible pages around fault address.
On read page fault, if filesystem provides ->map_pages(), we try to map up
to FAULT_AROUND_PAGES pages around page fault address in hope to reduce
number of minor page faults.
We call ->map_pages first and use ->fault() as fallback if page by the
offset is not ready to be mapped (cold page cache or something).
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 22:37:18 +00:00
|
|
|
void (*map_pages)(struct vm_area_struct *vma, struct vm_fault *vmf);
|
2006-06-23 09:03:43 +00:00
|
|
|
|
|
|
|
/* notification that a previously read-only page is about to become
|
|
|
|
* writable, if an error is returned it will cause a SIGBUS */
|
2009-03-31 22:23:21 +00:00
|
|
|
int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);
|
2008-07-24 04:27:05 +00:00
|
|
|
|
2015-04-15 23:15:11 +00:00
|
|
|
/* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
|
|
|
|
int (*pfn_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf);
|
|
|
|
|
2008-07-24 04:27:05 +00:00
|
|
|
/* called by access_process_vm when get_user_pages() fails, typically
|
|
|
|
* for use by special VMAs that can switch between memory and hardware
|
|
|
|
*/
|
|
|
|
int (*access)(struct vm_area_struct *vma, unsigned long addr,
|
|
|
|
void *buf, int len, int write);
|
2014-05-19 22:58:32 +00:00
|
|
|
|
|
|
|
/* Called by the /proc/PID/maps code to ask the vma whether it
|
|
|
|
* has a special name. Returning non-NULL will also cause this
|
|
|
|
* vma to be dumped unconditionally. */
|
|
|
|
const char *(*name)(struct vm_area_struct *vma);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#ifdef CONFIG_NUMA
|
2008-04-28 09:13:14 +00:00
|
|
|
/*
|
|
|
|
* set_policy() op must add a reference to any non-NULL @new mempolicy
|
|
|
|
* to hold the policy upon return. Caller should pass NULL @new to
|
|
|
|
* remove a policy and fall back to surrounding context--i.e. do not
|
|
|
|
* install a MPOL_DEFAULT policy, nor the task or system default
|
|
|
|
* mempolicy.
|
|
|
|
*/
|
2005-04-16 22:20:36 +00:00
|
|
|
int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
|
2008-04-28 09:13:14 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* get_policy() op must add reference [mpol_get()] to any policy at
|
|
|
|
* (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
|
|
|
|
* in mm/mempolicy.c will do this automatically.
|
|
|
|
* get_policy() must NOT add a ref if the policy at (vma,addr) is not
|
|
|
|
* marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
|
|
|
|
* If no [shared/vma] mempolicy exists at the addr, get_policy() op
|
|
|
|
* must return NULL--i.e., do not "fallback" to task or system default
|
|
|
|
* policy.
|
|
|
|
*/
|
2005-04-16 22:20:36 +00:00
|
|
|
struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
|
|
|
|
unsigned long addr);
|
|
|
|
#endif
|
2014-12-18 14:48:15 +00:00
|
|
|
/*
|
|
|
|
* Called by vm_normal_page() for special PTEs to find the
|
|
|
|
* page for @addr. This is useful if the default behavior
|
|
|
|
* (using pte_page()) would not find the correct page.
|
|
|
|
*/
|
|
|
|
struct page *(*find_special_page)(struct vm_area_struct *vma,
|
|
|
|
unsigned long addr);
|
2005-04-16 22:20:36 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
struct mmu_gather;
|
|
|
|
struct inode;
|
|
|
|
|
2006-01-08 09:04:36 +00:00
|
|
|
#define page_private(page) ((page)->private)
|
|
|
|
#define set_page_private(page, v) ((page)->private = (v))
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
|
2012-10-08 23:32:08 +00:00
|
|
|
/* It's valid only if the page is free path or free_list */
|
|
|
|
static inline void set_freepage_migratetype(struct page *page, int migratetype)
|
|
|
|
{
|
2012-10-08 23:32:11 +00:00
|
|
|
page->index = migratetype;
|
2012-10-08 23:32:08 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* It's valid only if the page is free path or free_list */
|
|
|
|
static inline int get_freepage_migratetype(struct page *page)
|
|
|
|
{
|
2012-10-08 23:32:11 +00:00
|
|
|
return page->index;
|
2012-10-08 23:32:08 +00:00
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* FIXME: take this include out, include page-flags.h in
|
|
|
|
* files which need it (119 of them)
|
|
|
|
*/
|
|
|
|
#include <linux/page-flags.h>
|
thp: transparent hugepage core
Lately I've been working to make KVM use hugepages transparently without
the usual restrictions of hugetlbfs. Some of the restrictions I'd like to
see removed:
1) hugepages have to be swappable or the guest physical memory remains
locked in RAM and can't be paged out to swap
2) if a hugepage allocation fails, regular pages should be allocated
instead and mixed in the same vma without any failure and without
userland noticing
3) if some task quits and more hugepages become available in the
buddy, guest physical memory backed by regular pages should be
relocated on hugepages automatically in regions under
madvise(MADV_HUGEPAGE) (ideally event driven by waking up the
kernel deamon if the order=HPAGE_PMD_SHIFT-PAGE_SHIFT list becomes
not null)
4) avoidance of reservation and maximization of use of hugepages whenever
possible. Reservation (needed to avoid runtime fatal faliures) may be ok for
1 machine with 1 database with 1 database cache with 1 database cache size
known at boot time. It's definitely not feasible with a virtualization
hypervisor usage like RHEV-H that runs an unknown number of virtual machines
with an unknown size of each virtual machine with an unknown amount of
pagecache that could be potentially useful in the host for guest not using
O_DIRECT (aka cache=off).
hugepages in the virtualization hypervisor (and also in the guest!) are
much more important than in a regular host not using virtualization,
becasue with NPT/EPT they decrease the tlb-miss cacheline accesses from 24
to 19 in case only the hypervisor uses transparent hugepages, and they
decrease the tlb-miss cacheline accesses from 19 to 15 in case both the
linux hypervisor and the linux guest both uses this patch (though the
guest will limit the addition speedup to anonymous regions only for
now...). Even more important is that the tlb miss handler is much slower
on a NPT/EPT guest than for a regular shadow paging or no-virtualization
scenario. So maximizing the amount of virtual memory cached by the TLB
pays off significantly more with NPT/EPT than without (even if there would
be no significant speedup in the tlb-miss runtime).
The first (and more tedious) part of this work requires allowing the VM to
handle anonymous hugepages mixed with regular pages transparently on
regular anonymous vmas. This is what this patch tries to achieve in the
least intrusive possible way. We want hugepages and hugetlb to be used in
a way so that all applications can benefit without changes (as usual we
leverage the KVM virtualization design: by improving the Linux VM at
large, KVM gets the performance boost too).
The most important design choice is: always fallback to 4k allocation if
the hugepage allocation fails! This is the _very_ opposite of some large
pagecache patches that failed with -EIO back then if a 64k (or similar)
allocation failed...
Second important decision (to reduce the impact of the feature on the
existing pagetable handling code) is that at any time we can split an
hugepage into 512 regular pages and it has to be done with an operation
that can't fail. This way the reliability of the swapping isn't decreased
(no need to allocate memory when we are short on memory to swap) and it's
trivial to plug a split_huge_page* one-liner where needed without
polluting the VM. Over time we can teach mprotect, mremap and friends to
handle pmd_trans_huge natively without calling split_huge_page*. The fact
it can't fail isn't just for swap: if split_huge_page would return -ENOMEM
(instead of the current void) we'd need to rollback the mprotect from the
middle of it (ideally including undoing the split_vma) which would be a
big change and in the very wrong direction (it'd likely be simpler not to
call split_huge_page at all and to teach mprotect and friends to handle
hugepages instead of rolling them back from the middle). In short the
very value of split_huge_page is that it can't fail.
The collapsing and madvise(MADV_HUGEPAGE) part will remain separated and
incremental and it'll just be an "harmless" addition later if this initial
part is agreed upon. It also should be noted that locking-wise replacing
regular pages with hugepages is going to be very easy if compared to what
I'm doing below in split_huge_page, as it will only happen when
page_count(page) matches page_mapcount(page) if we can take the PG_lock
and mmap_sem in write mode. collapse_huge_page will be a "best effort"
that (unlike split_huge_page) can fail at the minimal sign of trouble and
we can try again later. collapse_huge_page will be similar to how KSM
works and the madvise(MADV_HUGEPAGE) will work similar to
madvise(MADV_MERGEABLE).
The default I like is that transparent hugepages are used at page fault
time. This can be changed with
/sys/kernel/mm/transparent_hugepage/enabled. The control knob can be set
to three values "always", "madvise", "never" which mean respectively that
hugepages are always used, or only inside madvise(MADV_HUGEPAGE) regions,
or never used. /sys/kernel/mm/transparent_hugepage/defrag instead
controls if the hugepage allocation should defrag memory aggressively
"always", only inside "madvise" regions, or "never".
The pmd_trans_splitting/pmd_trans_huge locking is very solid. The
put_page (from get_user_page users that can't use mmu notifier like
O_DIRECT) that runs against a __split_huge_page_refcount instead was a
pain to serialize in a way that would result always in a coherent page
count for both tail and head. I think my locking solution with a
compound_lock taken only after the page_first is valid and is still a
PageHead should be safe but it surely needs review from SMP race point of
view. In short there is no current existing way to serialize the O_DIRECT
final put_page against split_huge_page_refcount so I had to invent a new
one (O_DIRECT loses knowledge on the mapping status by the time gup_fast
returns so...). And I didn't want to impact all gup/gup_fast users for
now, maybe if we change the gup interface substantially we can avoid this
locking, I admit I didn't think too much about it because changing the gup
unpinning interface would be invasive.
If we ignored O_DIRECT we could stick to the existing compound refcounting
code, by simply adding a get_user_pages_fast_flags(foll_flags) where KVM
(and any other mmu notifier user) would call it without FOLL_GET (and if
FOLL_GET isn't set we'd just BUG_ON if nobody registered itself in the
current task mmu notifier list yet). But O_DIRECT is fundamental for
decent performance of virtualized I/O on fast storage so we can't avoid it
to solve the race of put_page against split_huge_page_refcount to achieve
a complete hugepage feature for KVM.
Swap and oom works fine (well just like with regular pages ;). MMU
notifier is handled transparently too, with the exception of the young bit
on the pmd, that didn't have a range check but I think KVM will be fine
because the whole point of hugepages is that EPT/NPT will also use a huge
pmd when they notice gup returns pages with PageCompound set, so they
won't care of a range and there's just the pmd young bit to check in that
case.
NOTE: in some cases if the L2 cache is small, this may slowdown and waste
memory during COWs because 4M of memory are accessed in a single fault
instead of 8k (the payoff is that after COW the program can run faster).
So we might want to switch the copy_huge_page (and clear_huge_page too) to
not temporal stores. I also extensively researched ways to avoid this
cache trashing with a full prefault logic that would cow in 8k/16k/32k/64k
up to 1M (I can send those patches that fully implemented prefault) but I
concluded they're not worth it and they add an huge additional complexity
and they remove all tlb benefits until the full hugepage has been faulted
in, to save a little bit of memory and some cache during app startup, but
they still don't improve substantially the cache-trashing during startup
if the prefault happens in >4k chunks. One reason is that those 4k pte
entries copied are still mapped on a perfectly cache-colored hugepage, so
the trashing is the worst one can generate in those copies (cow of 4k page
copies aren't so well colored so they trashes less, but again this results
in software running faster after the page fault). Those prefault patches
allowed things like a pte where post-cow pages were local 4k regular anon
pages and the not-yet-cowed pte entries were pointing in the middle of
some hugepage mapped read-only. If it doesn't payoff substantially with
todays hardware it will payoff even less in the future with larger l2
caches, and the prefault logic would blot the VM a lot. If one is
emebdded transparent_hugepage can be disabled during boot with sysfs or
with the boot commandline parameter transparent_hugepage=0 (or
transparent_hugepage=2 to restrict hugepages inside madvise regions) that
will ensure not a single hugepage is allocated at boot time. It is simple
enough to just disable transparent hugepage globally and let transparent
hugepages be allocated selectively by applications in the MADV_HUGEPAGE
region (both at page fault time, and if enabled with the
collapse_huge_page too through the kernel daemon).
This patch supports only hugepages mapped in the pmd, archs that have
smaller hugepages will not fit in this patch alone. Also some archs like
power have certain tlb limits that prevents mixing different page size in
the same regions so they will not fit in this framework that requires
"graceful fallback" to basic PAGE_SIZE in case of physical memory
fragmentation. hugetlbfs remains a perfect fit for those because its
software limits happen to match the hardware limits. hugetlbfs also
remains a perfect fit for hugepage sizes like 1GByte that cannot be hoped
to be found not fragmented after a certain system uptime and that would be
very expensive to defragment with relocation, so requiring reservation.
hugetlbfs is the "reservation way", the point of transparent hugepages is
not to have any reservation at all and maximizing the use of cache and
hugepages at all times automatically.
Some performance result:
vmx andrea # LD_PRELOAD=/usr/lib64/libhugetlbfs.so HUGETLB_MORECORE=yes HUGETLB_PATH=/mnt/huge/ ./largep
ages3
memset page fault 1566023
memset tlb miss 453854
memset second tlb miss 453321
random access tlb miss 41635
random access second tlb miss 41658
vmx andrea # LD_PRELOAD=/usr/lib64/libhugetlbfs.so HUGETLB_MORECORE=yes HUGETLB_PATH=/mnt/huge/ ./largepages3
memset page fault 1566471
memset tlb miss 453375
memset second tlb miss 453320
random access tlb miss 41636
random access second tlb miss 41637
vmx andrea # ./largepages3
memset page fault 1566642
memset tlb miss 453417
memset second tlb miss 453313
random access tlb miss 41630
random access second tlb miss 41647
vmx andrea # ./largepages3
memset page fault 1566872
memset tlb miss 453418
memset second tlb miss 453315
random access tlb miss 41618
random access second tlb miss 41659
vmx andrea # echo 0 > /proc/sys/vm/transparent_hugepage
vmx andrea # ./largepages3
memset page fault 2182476
memset tlb miss 460305
memset second tlb miss 460179
random access tlb miss 44483
random access second tlb miss 44186
vmx andrea # ./largepages3
memset page fault 2182791
memset tlb miss 460742
memset second tlb miss 459962
random access tlb miss 43981
random access second tlb miss 43988
============
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#define SIZE (3UL*1024*1024*1024)
int main()
{
char *p = malloc(SIZE), *p2;
struct timeval before, after;
gettimeofday(&before, NULL);
memset(p, 0, SIZE);
gettimeofday(&after, NULL);
printf("memset page fault %Lu\n",
(after.tv_sec-before.tv_sec)*1000000UL +
after.tv_usec-before.tv_usec);
gettimeofday(&before, NULL);
memset(p, 0, SIZE);
gettimeofday(&after, NULL);
printf("memset tlb miss %Lu\n",
(after.tv_sec-before.tv_sec)*1000000UL +
after.tv_usec-before.tv_usec);
gettimeofday(&before, NULL);
memset(p, 0, SIZE);
gettimeofday(&after, NULL);
printf("memset second tlb miss %Lu\n",
(after.tv_sec-before.tv_sec)*1000000UL +
after.tv_usec-before.tv_usec);
gettimeofday(&before, NULL);
for (p2 = p; p2 < p+SIZE; p2 += 4096)
*p2 = 0;
gettimeofday(&after, NULL);
printf("random access tlb miss %Lu\n",
(after.tv_sec-before.tv_sec)*1000000UL +
after.tv_usec-before.tv_usec);
gettimeofday(&before, NULL);
for (p2 = p; p2 < p+SIZE; p2 += 4096)
*p2 = 0;
gettimeofday(&after, NULL);
printf("random access second tlb miss %Lu\n",
(after.tv_sec-before.tv_sec)*1000000UL +
after.tv_usec-before.tv_usec);
return 0;
}
============
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 23:46:52 +00:00
|
|
|
#include <linux/huge_mm.h>
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Methods to modify the page usage count.
|
|
|
|
*
|
|
|
|
* What counts for a page usage:
|
|
|
|
* - cache mapping (page->mapping)
|
|
|
|
* - private data (page->private)
|
|
|
|
* - page mapped in a task's page tables, each mapping
|
|
|
|
* is counted separately
|
|
|
|
*
|
|
|
|
* Also, many kernel routines increase the page count before a critical
|
|
|
|
* routine so they can be sure the page doesn't go away from under them.
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
2006-09-26 06:31:35 +00:00
|
|
|
* Drop a ref, return true if the refcount fell to zero (the page has no users)
|
2005-04-16 22:20:36 +00:00
|
|
|
*/
|
2006-03-22 08:08:03 +00:00
|
|
|
static inline int put_page_testzero(struct page *page)
|
|
|
|
{
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0, page);
|
2006-03-22 08:08:03 +00:00
|
|
|
return atomic_dec_and_test(&page->_count);
|
2006-03-22 08:08:03 +00:00
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/*
|
2006-03-22 08:08:03 +00:00
|
|
|
* Try to grab a ref unless the page has a refcount of zero, return false if
|
|
|
|
* that is the case.
|
2013-08-28 08:37:42 +00:00
|
|
|
* This can be called when MMU is off so it must not access
|
|
|
|
* any of the virtual mappings.
|
2005-04-16 22:20:36 +00:00
|
|
|
*/
|
2006-03-22 08:08:03 +00:00
|
|
|
static inline int get_page_unless_zero(struct page *page)
|
|
|
|
{
|
2006-03-22 08:08:03 +00:00
|
|
|
return atomic_inc_not_zero(&page->_count);
|
2006-03-22 08:08:03 +00:00
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2013-08-28 08:37:42 +00:00
|
|
|
/*
|
|
|
|
* Try to drop a ref unless the page has a refcount of one, return false if
|
|
|
|
* that is the case.
|
|
|
|
* This is to make sure that the refcount won't become zero after this drop.
|
|
|
|
* This can be called when MMU is off so it must not access
|
|
|
|
* any of the virtual mappings.
|
|
|
|
*/
|
|
|
|
static inline int put_page_unless_one(struct page *page)
|
|
|
|
{
|
|
|
|
return atomic_add_unless(&page->_count, -1, 1);
|
|
|
|
}
|
|
|
|
|
2010-01-27 03:06:39 +00:00
|
|
|
extern int page_is_ram(unsigned long pfn);
|
x86: optimize resource lookups for ioremap
We have a large university system in the UK that is experiencing very long
delays modprobing the driver for a specific I/O device. The delay is from
8-10 minutes per device and there are 31 devices in the system. This 4 to
5 hour delay in starting up those I/O devices is very much a burden on the
customer.
There are two causes for requiring a restart/reload of the drivers. First
is periodic preventive maintenance (PM) and the second is if any of the
devices experience a fatal error. Both of these trigger this excessively
long delay in bringing the system back up to full capability.
The problem was tracked down to a very slow IOREMAP operation and the
excessively long ioresource lookup to insure that the user is not
attempting to ioremap RAM. These patches provide a speed up to that
function.
The modprobe time appears to be affected quite a bit by previous activity
on the ioresource list, which I suspect is due to cache preloading. While
the overall improvement is impacted by other overhead of starting the
devices, this drastically improves the modprobe time.
Also our system is considerably smaller so the percentages gained will not
be the same. Best case improvement with the modprobe on our 20 device
smallish system was from 'real 5m51.913s' to 'real 0m18.275s'.
This patch (of 2):
Since the ioremap operation is verifying that the specified address range
is NOT RAM, it will search the entire ioresource list if the condition is
true. To make matters worse, it does this one 4k page at a time. For a
128M BAR region this is 32 passes to determine the entire region does not
contain any RAM addresses.
This patch provides another resource lookup function, region_is_ram, that
searches for the entire region specified, verifying that it is completely
contained within the resource region. If it is found, then it is checked
to be RAM or not, within a single pass.
The return result reflects if it was found or not (-1), and whether it is
RAM (1) or not (0). This allows the caller to fallback to the previous
page by page search if it was not found.
[akpm@linux-foundation.org: fix spellos and typos in comment]
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Alex Thorlton <athorlton@sgi.com>
Reviewed-by: Cliff Wickman <cpw@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-13 22:54:03 +00:00
|
|
|
extern int region_is_ram(resource_size_t phys_addr, unsigned long size);
|
2010-01-27 03:06:39 +00:00
|
|
|
|
2008-02-05 06:28:31 +00:00
|
|
|
/* Support for virtually mapped pages */
|
2008-02-05 06:28:32 +00:00
|
|
|
struct page *vmalloc_to_page(const void *addr);
|
|
|
|
unsigned long vmalloc_to_pfn(const void *addr);
|
2008-02-05 06:28:31 +00:00
|
|
|
|
2008-03-12 07:51:31 +00:00
|
|
|
/*
|
|
|
|
* Determine if an address is within the vmalloc range
|
|
|
|
*
|
|
|
|
* On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
|
|
|
|
* is no special casing required.
|
|
|
|
*/
|
2008-02-05 06:28:34 +00:00
|
|
|
static inline int is_vmalloc_addr(const void *x)
|
|
|
|
{
|
2008-03-12 07:51:31 +00:00
|
|
|
#ifdef CONFIG_MMU
|
2008-02-05 06:28:34 +00:00
|
|
|
unsigned long addr = (unsigned long)x;
|
|
|
|
|
|
|
|
return addr >= VMALLOC_START && addr < VMALLOC_END;
|
2008-03-12 07:51:31 +00:00
|
|
|
#else
|
|
|
|
return 0;
|
2008-02-23 23:23:37 +00:00
|
|
|
#endif
|
2008-03-12 07:51:31 +00:00
|
|
|
}
|
2009-09-22 23:45:49 +00:00
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
extern int is_vmalloc_or_module_addr(const void *x);
|
|
|
|
#else
|
2009-09-24 11:33:32 +00:00
|
|
|
static inline int is_vmalloc_or_module_addr(const void *x)
|
2009-09-22 23:45:49 +00:00
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#endif
|
2008-02-05 06:28:34 +00:00
|
|
|
|
2014-05-06 18:02:53 +00:00
|
|
|
extern void kvfree(const void *addr);
|
|
|
|
|
2011-01-13 23:46:32 +00:00
|
|
|
static inline void compound_lock(struct page *page)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(PageSlab(page), page);
|
2011-01-13 23:46:32 +00:00
|
|
|
bit_spin_lock(PG_compound_lock, &page->flags);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void compound_unlock(struct page *page)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(PageSlab(page), page);
|
2011-01-13 23:46:32 +00:00
|
|
|
bit_spin_unlock(PG_compound_lock, &page->flags);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long compound_lock_irqsave(struct page *page)
|
|
|
|
{
|
|
|
|
unsigned long uninitialized_var(flags);
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
|
|
local_irq_save(flags);
|
|
|
|
compound_lock(page);
|
|
|
|
#endif
|
|
|
|
return flags;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void compound_unlock_irqrestore(struct page *page,
|
|
|
|
unsigned long flags)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
|
|
compound_unlock(page);
|
|
|
|
local_irq_restore(flags);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
mm: introdule compound_head_by_tail()
Currently, in put_compound_page(), we have
======
if (likely(!PageTail(page))) { <------ (1)
if (put_page_testzero(page)) {
/*
¦* By the time all refcounts have been released
¦* split_huge_page cannot run anymore from under us.
¦*/
if (PageHead(page))
__put_compound_page(page);
else
__put_single_page(page);
}
return;
}
/* __split_huge_page_refcount can run under us */
page_head = compound_head(page); <------------ (2)
======
if at (1) , we fail the check, this means page is *likely* a tail page.
Then at (2), as compoud_head(page) is inlined, it is :
======
static inline struct page *compound_head(struct page *page)
{
if (unlikely(PageTail(page))) { <----------- (3)
struct page *head = page->first_page;
smp_rmb();
if (likely(PageTail(page)))
return head;
}
return page;
}
======
here, the (3) unlikely in the case is a negative hint, because it is
*likely* a tail page. So the check (3) in this case is not good, so I
introduce a helper for this case.
So this patch introduces compound_head_by_tail() which deals with a
possible tail page(though it could be spilt by a racy thread), and make
compound_head() a wrapper on it.
This patch has no functional change, and it reduces the object
size slightly:
text data bss dec hex filename
11003 1328 16 12347 303b mm/swap.o.orig
10971 1328 16 12315 301b mm/swap.o.patched
I've ran "perf top -e branch-miss" to observe branch-miss in this case.
As Michael points out, it's a slow path, so only very few times this case
happens. But I grep'ed the code base, and found there still are some
other call sites could be benifited from this helper. And given that it
only bloating up the source by only 5 lines, but with a reduced object
size. I still believe this helper deserves to exsit.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:08:02 +00:00
|
|
|
static inline struct page *compound_head_by_tail(struct page *tail)
|
|
|
|
{
|
|
|
|
struct page *head = tail->first_page;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* page->first_page may be a dangling pointer to an old
|
|
|
|
* compound page, so recheck that it is still a tail
|
|
|
|
* page before returning.
|
|
|
|
*/
|
|
|
|
smp_rmb();
|
|
|
|
if (likely(PageTail(tail)))
|
|
|
|
return head;
|
|
|
|
return tail;
|
|
|
|
}
|
|
|
|
|
2015-02-10 22:09:35 +00:00
|
|
|
/*
|
|
|
|
* Since either compound page could be dismantled asynchronously in THP
|
|
|
|
* or we access asynchronously arbitrary positioned struct page, there
|
|
|
|
* would be tail flag race. To handle this race, we should call
|
|
|
|
* smp_rmb() before checking tail flag. compound_head_by_tail() did it.
|
|
|
|
*/
|
2007-05-06 21:49:39 +00:00
|
|
|
static inline struct page *compound_head(struct page *page)
|
|
|
|
{
|
mm: introdule compound_head_by_tail()
Currently, in put_compound_page(), we have
======
if (likely(!PageTail(page))) { <------ (1)
if (put_page_testzero(page)) {
/*
¦* By the time all refcounts have been released
¦* split_huge_page cannot run anymore from under us.
¦*/
if (PageHead(page))
__put_compound_page(page);
else
__put_single_page(page);
}
return;
}
/* __split_huge_page_refcount can run under us */
page_head = compound_head(page); <------------ (2)
======
if at (1) , we fail the check, this means page is *likely* a tail page.
Then at (2), as compoud_head(page) is inlined, it is :
======
static inline struct page *compound_head(struct page *page)
{
if (unlikely(PageTail(page))) { <----------- (3)
struct page *head = page->first_page;
smp_rmb();
if (likely(PageTail(page)))
return head;
}
return page;
}
======
here, the (3) unlikely in the case is a negative hint, because it is
*likely* a tail page. So the check (3) in this case is not good, so I
introduce a helper for this case.
So this patch introduces compound_head_by_tail() which deals with a
possible tail page(though it could be spilt by a racy thread), and make
compound_head() a wrapper on it.
This patch has no functional change, and it reduces the object
size slightly:
text data bss dec hex filename
11003 1328 16 12347 303b mm/swap.o.orig
10971 1328 16 12315 301b mm/swap.o.patched
I've ran "perf top -e branch-miss" to observe branch-miss in this case.
As Michael points out, it's a slow path, so only very few times this case
happens. But I grep'ed the code base, and found there still are some
other call sites could be benifited from this helper. And given that it
only bloating up the source by only 5 lines, but with a reduced object
size. I still believe this helper deserves to exsit.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 23:08:02 +00:00
|
|
|
if (unlikely(PageTail(page)))
|
|
|
|
return compound_head_by_tail(page);
|
2007-05-06 21:49:39 +00:00
|
|
|
return page;
|
|
|
|
}
|
|
|
|
|
2015-02-10 22:09:35 +00:00
|
|
|
/*
|
|
|
|
* If we access compound page synchronously such as access to
|
|
|
|
* allocated page, there is no need to handle tail flag race, so we can
|
|
|
|
* check tail flag directly without any synchronization primitive.
|
|
|
|
*/
|
|
|
|
static inline struct page *compound_head_fast(struct page *page)
|
|
|
|
{
|
|
|
|
if (unlikely(PageTail(page)))
|
|
|
|
return page->first_page;
|
|
|
|
return page;
|
|
|
|
}
|
|
|
|
|
2011-11-02 20:36:59 +00:00
|
|
|
/*
|
|
|
|
* The atomic page->_mapcount, starts from -1: so that transitions
|
|
|
|
* both from it and to it can be tracked, using atomic_inc_and_test
|
|
|
|
* and atomic_add_negative(-1).
|
|
|
|
*/
|
2013-02-23 00:34:59 +00:00
|
|
|
static inline void page_mapcount_reset(struct page *page)
|
2011-11-02 20:36:59 +00:00
|
|
|
{
|
|
|
|
atomic_set(&(page)->_mapcount, -1);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int page_mapcount(struct page *page)
|
|
|
|
{
|
2015-02-11 23:24:48 +00:00
|
|
|
VM_BUG_ON_PAGE(PageSlab(page), page);
|
|
|
|
return atomic_read(&page->_mapcount) + 1;
|
2011-11-02 20:36:59 +00:00
|
|
|
}
|
|
|
|
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
static inline int page_count(struct page *page)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2007-05-06 21:49:39 +00:00
|
|
|
return atomic_read(&compound_head(page)->_count);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2014-01-21 23:48:54 +00:00
|
|
|
static inline bool __compound_tail_refcounted(struct page *page)
|
|
|
|
{
|
2015-06-24 23:56:33 +00:00
|
|
|
return PageAnon(page) && !PageSlab(page) && !PageHeadHuge(page);
|
2014-01-21 23:48:54 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This takes a head page as parameter and tells if the
|
|
|
|
* tail page reference counting can be skipped.
|
|
|
|
*
|
|
|
|
* For this to be safe, PageSlab and PageHeadHuge must remain true on
|
|
|
|
* any given page where they return true here, until all tail pins
|
|
|
|
* have been released.
|
|
|
|
*/
|
|
|
|
static inline bool compound_tail_refcounted(struct page *page)
|
|
|
|
{
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(!PageHead(page), page);
|
2014-01-21 23:48:54 +00:00
|
|
|
return __compound_tail_refcounted(page);
|
|
|
|
}
|
|
|
|
|
2011-11-02 20:37:36 +00:00
|
|
|
static inline void get_huge_page_tail(struct page *page)
|
|
|
|
{
|
|
|
|
/*
|
2014-01-21 23:49:04 +00:00
|
|
|
* __split_huge_page_refcount() cannot run from under us.
|
2011-11-02 20:37:36 +00:00
|
|
|
*/
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(!PageTail(page), page);
|
|
|
|
VM_BUG_ON_PAGE(page_mapcount(page) < 0, page);
|
|
|
|
VM_BUG_ON_PAGE(atomic_read(&page->_count) != 0, page);
|
2014-01-21 23:49:04 +00:00
|
|
|
if (compound_tail_refcounted(page->first_page))
|
2014-01-21 23:48:54 +00:00
|
|
|
atomic_inc(&page->_mapcount);
|
2011-11-02 20:37:36 +00:00
|
|
|
}
|
|
|
|
|
2011-11-02 20:36:59 +00:00
|
|
|
extern bool __get_page_tail(struct page *page);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
static inline void get_page(struct page *page)
|
|
|
|
{
|
2011-11-02 20:36:59 +00:00
|
|
|
if (unlikely(PageTail(page)))
|
|
|
|
if (likely(__get_page_tail(page)))
|
|
|
|
return;
|
2011-01-13 23:46:32 +00:00
|
|
|
/*
|
|
|
|
* Getting a normal page or the head of a compound page
|
2011-11-02 20:36:59 +00:00
|
|
|
* requires to already have an elevated page->_count.
|
2011-01-13 23:46:32 +00:00
|
|
|
*/
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page);
|
2005-04-16 22:20:36 +00:00
|
|
|
atomic_inc(&page->_count);
|
|
|
|
}
|
|
|
|
|
2007-05-06 21:49:41 +00:00
|
|
|
static inline struct page *virt_to_head_page(const void *x)
|
|
|
|
{
|
|
|
|
struct page *page = virt_to_page(x);
|
2015-02-10 22:09:35 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* We don't need to worry about synchronization of tail flag
|
|
|
|
* when we call virt_to_head_page() since it is only called for
|
|
|
|
* already allocated page and this page won't be freed until
|
|
|
|
* this virt_to_head_page() is finished. So use _fast variant.
|
|
|
|
*/
|
|
|
|
return compound_head_fast(page);
|
2007-05-06 21:49:41 +00:00
|
|
|
}
|
|
|
|
|
2006-03-22 08:08:40 +00:00
|
|
|
/*
|
|
|
|
* Setup the page count before being freed into the page allocator for
|
|
|
|
* the first time (boot or memory hotplug)
|
|
|
|
*/
|
|
|
|
static inline void init_page_count(struct page *page)
|
|
|
|
{
|
|
|
|
atomic_set(&page->_count, 1);
|
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
void put_page(struct page *page);
|
2006-08-14 06:24:27 +00:00
|
|
|
void put_pages_list(struct list_head *pages);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-03-22 08:08:05 +00:00
|
|
|
void split_page(struct page *page, unsigned int order);
|
2010-05-24 21:32:27 +00:00
|
|
|
int split_free_page(struct page *page);
|
2006-03-22 08:08:05 +00:00
|
|
|
|
2006-12-07 04:33:32 +00:00
|
|
|
/*
|
|
|
|
* Compound pages have a destructor function. Provide a
|
|
|
|
* prototype for that function and accessor functions.
|
|
|
|
* These are _only_ valid on the head of a PG_compound page.
|
|
|
|
*/
|
|
|
|
|
|
|
|
static inline void set_compound_page_dtor(struct page *page,
|
|
|
|
compound_page_dtor *dtor)
|
|
|
|
{
|
2015-02-11 23:24:46 +00:00
|
|
|
page[1].compound_dtor = dtor;
|
2006-12-07 04:33:32 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
|
|
|
|
{
|
2015-02-11 23:24:46 +00:00
|
|
|
return page[1].compound_dtor;
|
2006-12-07 04:33:32 +00:00
|
|
|
}
|
|
|
|
|
2007-05-06 21:49:39 +00:00
|
|
|
static inline int compound_order(struct page *page)
|
|
|
|
{
|
2007-05-06 21:49:40 +00:00
|
|
|
if (!PageHead(page))
|
2007-05-06 21:49:39 +00:00
|
|
|
return 0;
|
2015-02-11 23:24:46 +00:00
|
|
|
return page[1].compound_order;
|
2007-05-06 21:49:39 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void set_compound_order(struct page *page, unsigned long order)
|
|
|
|
{
|
2015-02-11 23:24:46 +00:00
|
|
|
page[1].compound_order = order;
|
2007-05-06 21:49:39 +00:00
|
|
|
}
|
|
|
|
|
2011-01-21 07:49:56 +00:00
|
|
|
#ifdef CONFIG_MMU
|
2011-01-13 23:46:37 +00:00
|
|
|
/*
|
|
|
|
* Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
|
|
|
|
* servicing faults for write access. In the normal case, do always want
|
|
|
|
* pte_mkwrite. But get_user_pages can cause write faults for mappings
|
|
|
|
* that do not have writing enabled, when used by access_process_vm.
|
|
|
|
*/
|
|
|
|
static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
|
|
|
|
{
|
|
|
|
if (likely(vma->vm_flags & VM_WRITE))
|
|
|
|
pte = pte_mkwrite(pte);
|
|
|
|
return pte;
|
|
|
|
}
|
mm: introduce vm_ops->map_pages()
Here's new version of faultaround patchset. It took a while to tune it
and collect performance data.
First patch adds new callback ->map_pages to vm_operations_struct.
->map_pages() is called when VM asks to map easy accessible pages.
Filesystem should find and map pages associated with offsets from
"pgoff" till "max_pgoff". ->map_pages() is called with page table
locked and must not block. If it's not possible to reach a page without
blocking, filesystem should skip it. Filesystem should use do_set_pte()
to setup page table entry. Pointer to entry associated with offset
"pgoff" is passed in "pte" field in vm_fault structure. Pointers to
entries for other offsets should be calculated relative to "pte".
Currently VM use ->map_pages only on read page fault path. We try to
map FAULT_AROUND_PAGES a time. FAULT_AROUND_PAGES is 16 for now.
Performance data for different FAULT_AROUND_ORDER is below.
TODO:
- implement ->map_pages() for shmem/tmpfs;
- modify get_user_pages() to be able to use ->map_pages() and implement
mmap(MAP_POPULATE|MAP_NONBLOCK) on top.
=========================================================================
Tested on 4-socket machine (120 threads) with 128GiB of RAM.
Few real-world workloads. The sweet spot for FAULT_AROUND_ORDER here is
somewhere between 3 and 5. Let's say 4 :)
Linux build (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 283,301,572 247,151,987 212,215,789 204,772,882 199,568,944 194,703,779 193,381,485
time, seconds 151.227629483 153.920996480 151.356125472 150.863792049 150.879207877 151.150764954 151.450962358
Linux rebuild (make -j60)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 5,396,854 4,148,444 2,855,286 2,577,282 2,361,957 2,169,573 2,112,643
time, seconds 27.404543757 27.559725591 27.030057426 26.855045126 26.678618635 26.974523490 26.761320095
Git test suite (make -j60 test)
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
minor-faults 129,591,823 99,200,751 66,106,718 57,606,410 51,510,808 45,776,813 44,085,515
time, seconds 66.087215026 64.784546905 64.401156567 65.282708668 66.034016829 66.793780811 67.237810413
Two synthetic tests: access every word in file in sequential/random order.
It doesn't improve much after FAULT_AROUND_ORDER == 4.
Sequential access 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 4,195,437 2,098,275 525,068 262,251 131,170 32,856 8,282
time, seconds 7.250461742 6.461711074 5.493859139 5.488488147 5.707213983 5.898510832 5.109232856
8 threads
minor-faults 33,557,540 16,892,728 4,515,848 2,366,999 1,423,382 442,732 142,339
time, seconds 16.649304881 9.312555263 6.612490639 6.394316732 6.669827501 6.75078944 6.371900528
32 threads
minor-faults 134,228,222 67,526,810 17,725,386 9,716,537 4,763,731 1,668,921 537,200
time, seconds 49.164430543 29.712060103 12.938649729 10.175151004 11.840094583 9.594081325 9.928461797
60 threads
minor-faults 251,687,988 126,146,952 32,919,406 18,208,804 10,458,947 2,733,907 928,217
time, seconds 86.260656897 49.626551828 22.335007632 17.608243696 16.523119035 16.339489186 16.326390902
120 threads
minor-faults 503,352,863 252,939,677 67,039,168 35,191,827 19,170,091 4,688,357 1,471,862
time, seconds 124.589206333 79.757867787 39.508707872 32.167281632 29.972989292 28.729834575 28.042251622
Random access 1GiB file
1 thread
minor-faults 262,636 132,743 34,369 17,299 8,527 3,451 1,222
time, seconds 15.351890914 16.613802482 16.569227308 15.179220992 16.557356122 16.578247824 15.365266994
8 threads
minor-faults 2,098,948 1,061,871 273,690 154,501 87,110 25,663 7,384
time, seconds 15.040026343 15.096933500 14.474757288 14.289129964 14.411537468 14.296316837 14.395635804
32 threads
minor-faults 8,390,734 4,231,023 1,054,432 528,847 269,242 97,746 26,881
time, seconds 20.430433109 21.585235358 22.115062928 14.872878951 14.880856305 14.883370649 14.821261690
60 threads
minor-faults 15,733,258 7,892,809 1,973,393 988,266 594,789 164,994 51,691
time, seconds 26.577302548 25.692397770 18.728863715 20.153026398 21.619101933 17.745086260 17.613215273
120 threads
minor-faults 31,471,111 15,816,616 3,959,209 1,978,685 1,008,299 264,635 96,010
time, seconds 41.835322703 40.459786095 36.085306105 35.313894834 35.814445675 36.552633793 34.289210594
Touch only one page in page table in 16GiB file
FAULT_AROUND_ORDER Baseline 1 3 4 5 7 9
1 thread
minor-faults 8,372 8,324 8,270 8,260 8,249 8,239 8,237
time, seconds 0.039892712 0.045369149 0.051846126 0.063681685 0.079095975 0.17652406 0.541213386
8 threads
minor-faults 65,731 65,681 65,628 65,620 65,608 65,599 65,596
time, seconds 0.124159196 0.488600638 0.156854426 0.191901957 0.242631486 0.543569456 1.677303984
32 threads
minor-faults 262,388 262,341 262,285 262,276 262,266 262,257 263,183
time, seconds 0.452421421 0.488600638 0.565020946 0.648229739 0.789850823 1.651584361 5.000361559
60 threads
minor-faults 491,822 491,792 491,723 491,711 491,701 491,691 491,825
time, seconds 0.763288616 0.869620515 0.980727360 1.161732354 1.466915814 3.04041448 9.308612938
120 threads
minor-faults 983,466 983,655 983,366 983,372 983,363 984,083 984,164
time, seconds 1.595846553 1.667902182 2.008959376 2.425380942 2.941368804 5.977807890 18.401846125
This patch (of 2):
Introduce new vm_ops callback ->map_pages() and uses it for mapping easy
accessible pages around fault address.
On read page fault, if filesystem provides ->map_pages(), we try to map up
to FAULT_AROUND_PAGES pages around page fault address in hope to reduce
number of minor page faults.
We call ->map_pages first and use ->fault() as fallback if page by the
offset is not ready to be mapped (cold page cache or something).
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 22:37:18 +00:00
|
|
|
|
|
|
|
void do_set_pte(struct vm_area_struct *vma, unsigned long address,
|
|
|
|
struct page *page, pte_t *pte, bool write, bool anon);
|
2011-01-21 07:49:56 +00:00
|
|
|
#endif
|
2011-01-13 23:46:37 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* Multiple processes may "see" the same page. E.g. for untouched
|
|
|
|
* mappings of /dev/null, all processes see the same page full of
|
|
|
|
* zeroes, and text pages of executables and shared libraries have
|
|
|
|
* only one copy in memory, at most, normally.
|
|
|
|
*
|
|
|
|
* For the non-reserved pages, page_count(page) denotes a reference count.
|
2005-09-21 16:55:38 +00:00
|
|
|
* page_count() == 0 means the page is free. page->lru is then used for
|
|
|
|
* freelist management in the buddy allocator.
|
2006-09-26 06:31:35 +00:00
|
|
|
* page_count() > 0 means the page has been allocated.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* Pages are allocated by the slab allocator in order to provide memory
|
|
|
|
* to kmalloc and kmem_cache_alloc. In this case, the management of the
|
|
|
|
* page, and the fields in 'struct page' are the responsibility of mm/slab.c
|
|
|
|
* unless a particular usage is carefully commented. (the responsibility of
|
|
|
|
* freeing the kmalloc memory is the caller's, of course).
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* A page may be used by anyone else who does a __get_free_page().
|
|
|
|
* In this case, page_count still tracks the references, and should only
|
|
|
|
* be used through the normal accessor functions. The top bits of page->flags
|
|
|
|
* and page->virtual store page management information, but all other fields
|
|
|
|
* are unused and could be used privately, carefully. The management of this
|
|
|
|
* page is the responsibility of the one who allocated it, and those who have
|
|
|
|
* subsequently been given references to it.
|
|
|
|
*
|
|
|
|
* The other pages (we may call them "pagecache pages") are completely
|
2005-04-16 22:20:36 +00:00
|
|
|
* managed by the Linux memory manager: I/O, buffers, swapping etc.
|
|
|
|
* The following discussion applies only to them.
|
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* A pagecache page contains an opaque `private' member, which belongs to the
|
|
|
|
* page's address_space. Usually, this is the address of a circular list of
|
|
|
|
* the page's disk buffers. PG_private must be set to tell the VM to call
|
|
|
|
* into the filesystem to release these pages.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* A page may belong to an inode's memory mapping. In this case, page->mapping
|
|
|
|
* is the pointer to the inode, and page->index is the file offset of the page,
|
|
|
|
* in units of PAGE_CACHE_SIZE.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* If pagecache pages are not associated with an inode, they are said to be
|
|
|
|
* anonymous pages. These may become associated with the swapcache, and in that
|
|
|
|
* case PG_swapcache is set, and page->private is an offset into the swapcache.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* In either case (swapcache or inode backed), the pagecache itself holds one
|
|
|
|
* reference to the page. Setting PG_private should also increment the
|
|
|
|
* refcount. The each user mapping also has a reference to the page.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* The pagecache pages are stored in a per-mapping radix tree, which is
|
|
|
|
* rooted at mapping->page_tree, and indexed by offset.
|
|
|
|
* Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
|
|
|
|
* lists, we instead now tag pages as dirty/writeback in the radix tree.
|
2005-04-16 22:20:36 +00:00
|
|
|
*
|
2006-09-26 06:31:35 +00:00
|
|
|
* All pagecache pages may be subject to I/O:
|
2005-04-16 22:20:36 +00:00
|
|
|
* - inode pages may need to be read from disk,
|
|
|
|
* - inode pages which have been modified and are MAP_SHARED may need
|
2006-09-26 06:31:35 +00:00
|
|
|
* to be written back to the inode on disk,
|
|
|
|
* - anonymous pages (including MAP_PRIVATE file mappings) which have been
|
|
|
|
* modified may need to be swapped out to swap space and (later) to be read
|
|
|
|
* back into memory.
|
2005-04-16 22:20:36 +00:00
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The zone field is never updated after free_area_init_core()
|
|
|
|
* sets it, so none of the operations on it need to be atomic.
|
|
|
|
*/
|
2005-06-23 07:07:40 +00:00
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
/* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */
|
2005-11-05 16:25:53 +00:00
|
|
|
#define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)
|
|
|
|
#define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)
|
2013-10-07 10:29:20 +00:00
|
|
|
#define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
|
2005-06-23 07:07:40 +00:00
|
|
|
/*
|
2011-03-31 01:57:33 +00:00
|
|
|
* Define the bit shifts to access each section. For non-existent
|
2005-06-23 07:07:40 +00:00
|
|
|
* sections we define the shift as 0; that plus a 0 mask ensures
|
|
|
|
* the compiler will optimise away reference to them.
|
|
|
|
*/
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
|
|
|
|
#define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))
|
|
|
|
#define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))
|
2013-10-07 10:29:20 +00:00
|
|
|
#define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0))
|
2005-06-23 07:07:40 +00:00
|
|
|
|
2010-10-26 21:21:37 +00:00
|
|
|
/* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
|
|
|
|
#ifdef NODE_NOT_IN_PAGE_FLAGS
|
2006-12-07 04:31:45 +00:00
|
|
|
#define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)
|
2007-02-10 09:43:14 +00:00
|
|
|
#define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
|
|
|
|
SECTIONS_PGOFF : ZONES_PGOFF)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#else
|
2006-12-07 04:31:45 +00:00
|
|
|
#define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
|
2007-02-10 09:43:14 +00:00
|
|
|
#define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
|
|
|
|
NODES_PGOFF : ZONES_PGOFF)
|
2006-12-07 04:31:45 +00:00
|
|
|
#endif
|
|
|
|
|
2007-02-10 09:43:14 +00:00
|
|
|
#define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
|
2005-06-23 07:07:40 +00:00
|
|
|
|
2008-04-28 09:12:48 +00:00
|
|
|
#if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
|
|
|
|
#error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
|
2005-06-23 07:07:40 +00:00
|
|
|
#endif
|
|
|
|
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)
|
|
|
|
#define NODES_MASK ((1UL << NODES_WIDTH) - 1)
|
|
|
|
#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
|
numa: use LAST_CPUPID_SHIFT to calculate LAST_CPUPID_MASK
LAST_CPUPID_MASK is calculated using LAST_CPUPID_WIDTH. However
LAST_CPUPID_WIDTH itself can be 0. (when LAST_CPUPID_NOT_IN_PAGE_FLAGS is
set). In such a case LAST_CPUPID_MASK turns out to be 0.
But with recent commit 1ae71d0319: (mm: numa: bugfix for
LAST_CPUPID_NOT_IN_PAGE_FLAGS) if LAST_CPUPID_MASK is 0,
page_cpupid_xchg_last() and page_cpupid_reset_last() causes
page->_last_cpupid to be set to 0.
This causes performance regression. Its almost as if numa_balancing is
off.
Fix LAST_CPUPID_MASK by using LAST_CPUPID_SHIFT instead of
LAST_CPUPID_WIDTH.
Some performance numbers and perf stats with and without the fix.
(3.14-rc6)
----------
numa01
Performance counter stats for '/usr/bin/time -f %e %S %U %c %w -o start_bench.out -a ./numa01':
12,27,462 cs [100.00%]
2,41,957 migrations [100.00%]
1,68,01,713 faults [100.00%]
7,99,35,29,041 cache-misses
98,808 migrate:mm_migrate_pages [100.00%]
1407.690148814 seconds time elapsed
numa02
Performance counter stats for '/usr/bin/time -f %e %S %U %c %w -o start_bench.out -a ./numa02':
63,065 cs [100.00%]
14,364 migrations [100.00%]
2,08,118 faults [100.00%]
25,32,59,404 cache-misses
12 migrate:mm_migrate_pages [100.00%]
63.840827219 seconds time elapsed
(3.14-rc6 with fix)
-------------------
numa01
Performance counter stats for '/usr/bin/time -f %e %S %U %c %w -o start_bench.out -a ./numa01':
9,68,911 cs [100.00%]
1,01,414 migrations [100.00%]
88,38,697 faults [100.00%]
4,42,92,51,042 cache-misses
4,25,060 migrate:mm_migrate_pages [100.00%]
685.965331189 seconds time elapsed
numa02
Performance counter stats for '/usr/bin/time -f %e %S %U %c %w -o start_bench.out -a ./numa02':
17,543 cs [100.00%]
2,962 migrations [100.00%]
1,17,843 faults [100.00%]
11,80,61,644 cache-misses
12,358 migrate:mm_migrate_pages [100.00%]
20.380132343 seconds time elapsed
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 22:37:57 +00:00
|
|
|
#define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1)
|
2006-12-07 04:31:45 +00:00
|
|
|
#define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
|
2005-06-23 07:07:40 +00:00
|
|
|
|
2011-07-26 00:11:51 +00:00
|
|
|
static inline enum zone_type page_zonenum(const struct page *page)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2005-06-23 07:07:40 +00:00
|
|
|
return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2013-02-23 00:35:21 +00:00
|
|
|
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
|
|
|
|
#define SECTION_IN_PAGE_FLAGS
|
|
|
|
#endif
|
|
|
|
|
2006-12-07 04:31:45 +00:00
|
|
|
/*
|
2013-09-11 21:22:35 +00:00
|
|
|
* The identification function is mainly used by the buddy allocator for
|
|
|
|
* determining if two pages could be buddies. We are not really identifying
|
|
|
|
* the zone since we could be using the section number id if we do not have
|
|
|
|
* node id available in page flags.
|
|
|
|
* We only guarantee that it will return the same value for two combinable
|
|
|
|
* pages in a zone.
|
2006-12-07 04:31:45 +00:00
|
|
|
*/
|
2006-06-23 09:03:01 +00:00
|
|
|
static inline int page_zone_id(struct page *page)
|
|
|
|
{
|
2006-12-07 04:31:45 +00:00
|
|
|
return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
|
2005-06-23 07:07:40 +00:00
|
|
|
}
|
|
|
|
|
2006-12-07 04:33:03 +00:00
|
|
|
static inline int zone_to_nid(struct zone *zone)
|
2006-09-26 06:31:55 +00:00
|
|
|
{
|
2006-09-27 08:50:08 +00:00
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
return zone->node;
|
|
|
|
#else
|
|
|
|
return 0;
|
|
|
|
#endif
|
2006-09-26 06:31:55 +00:00
|
|
|
}
|
|
|
|
|
2006-12-07 04:31:45 +00:00
|
|
|
#ifdef NODE_NOT_IN_PAGE_FLAGS
|
2011-07-26 00:11:51 +00:00
|
|
|
extern int page_to_nid(const struct page *page);
|
2006-12-07 04:31:45 +00:00
|
|
|
#else
|
2011-07-26 00:11:51 +00:00
|
|
|
static inline int page_to_nid(const struct page *page)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
{
|
2006-12-07 04:31:45 +00:00
|
|
|
return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
}
|
2006-12-07 04:31:45 +00:00
|
|
|
#endif
|
|
|
|
|
2012-11-12 09:06:20 +00:00
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpu_pid_to_cpupid(int cpu, int pid)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
|
2012-11-12 09:06:20 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_pid(int cpupid)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return cpupid & LAST__PID_MASK;
|
2012-11-12 09:06:20 +00:00
|
|
|
}
|
2013-10-07 10:29:07 +00:00
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_cpu(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
|
2013-10-07 10:29:07 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_nid(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return cpu_to_node(cpupid_to_cpu(cpupid));
|
2013-10-07 10:29:07 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline bool cpupid_pid_unset(int cpupid)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
|
2013-10-07 10:29:07 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline bool cpupid_cpu_unset(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
|
2013-10-07 10:29:07 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:21 +00:00
|
|
|
static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
|
|
|
|
{
|
|
|
|
return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
|
|
|
|
}
|
|
|
|
|
|
|
|
#define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
|
2013-10-07 10:29:20 +00:00
|
|
|
#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
|
|
|
|
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
mm: numa: bugfix for LAST_CPUPID_NOT_IN_PAGE_FLAGS
When doing some numa tests on powerpc, I triggered an oops bug. I find
it is caused by using page->_last_cpupid. It should be initialized as
"-1 & LAST_CPUPID_MASK", but not "-1". Otherwise, in task_numa_fault(),
we will miss the checking (last_cpupid == (-1 & LAST_CPUPID_MASK)). And
finally cause an oops bug in task_numa_group(), since the online cpu is
less than possible cpu. This happen with CONFIG_SPARSE_VMEMMAP disabled
Call trace:
SMP NR_CPUS=64 NUMA PowerNV
Modules linked in:
CPU: 24 PID: 804 Comm: systemd-udevd Not tainted3.13.0-rc1+ #32
task: c000001e2746aa80 ti: c000001e32c50000 task.ti:c000001e32c50000
REGS: c000001e32c53510 TRAP: 0300 Not tainted(3.13.0-rc1+)
MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI> CR:28024424 XER: 20000000
CFAR: c000000000009324 DAR: 7265717569726857 DSISR:40000000 SOFTE: 1
NIP .task_numa_fault+0x1470/0x2370
LR .task_numa_fault+0x1468/0x2370
Call Trace:
.task_numa_fault+0x1468/0x2370 (unreliable)
.do_numa_page+0x480/0x4a0
.handle_mm_fault+0x4ec/0xc90
.do_page_fault+0x3a8/0x890
handle_page_fault+0x10/0x30
Instruction dump:
3c82fefb 3884b138 48d9cff1 60000000 48000574 3c62fefb3863af78 3c82fefb
3884b138 48d9cfd5 60000000 e93f0100 <812902e4> 7d2907b45529063e 7d2a07b4
---[ end trace 15f2510da5ae07cf ]---
Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-03 23:38:39 +00:00
|
|
|
return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
|
2013-10-07 10:29:07 +00:00
|
|
|
}
|
2013-10-07 10:29:20 +00:00
|
|
|
|
|
|
|
static inline int page_cpupid_last(struct page *page)
|
|
|
|
{
|
|
|
|
return page->_last_cpupid;
|
|
|
|
}
|
|
|
|
static inline void page_cpupid_reset_last(struct page *page)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
mm: numa: bugfix for LAST_CPUPID_NOT_IN_PAGE_FLAGS
When doing some numa tests on powerpc, I triggered an oops bug. I find
it is caused by using page->_last_cpupid. It should be initialized as
"-1 & LAST_CPUPID_MASK", but not "-1". Otherwise, in task_numa_fault(),
we will miss the checking (last_cpupid == (-1 & LAST_CPUPID_MASK)). And
finally cause an oops bug in task_numa_group(), since the online cpu is
less than possible cpu. This happen with CONFIG_SPARSE_VMEMMAP disabled
Call trace:
SMP NR_CPUS=64 NUMA PowerNV
Modules linked in:
CPU: 24 PID: 804 Comm: systemd-udevd Not tainted3.13.0-rc1+ #32
task: c000001e2746aa80 ti: c000001e32c50000 task.ti:c000001e32c50000
REGS: c000001e32c53510 TRAP: 0300 Not tainted(3.13.0-rc1+)
MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI> CR:28024424 XER: 20000000
CFAR: c000000000009324 DAR: 7265717569726857 DSISR:40000000 SOFTE: 1
NIP .task_numa_fault+0x1470/0x2370
LR .task_numa_fault+0x1468/0x2370
Call Trace:
.task_numa_fault+0x1468/0x2370 (unreliable)
.do_numa_page+0x480/0x4a0
.handle_mm_fault+0x4ec/0xc90
.do_page_fault+0x3a8/0x890
handle_page_fault+0x10/0x30
Instruction dump:
3c82fefb 3884b138 48d9cff1 60000000 48000574 3c62fefb3863af78 3c82fefb
3884b138 48d9cfd5 60000000 e93f0100 <812902e4> 7d2907b45529063e 7d2a07b4
---[ end trace 15f2510da5ae07cf ]---
Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-03 23:38:39 +00:00
|
|
|
page->_last_cpupid = -1 & LAST_CPUPID_MASK;
|
2012-11-12 09:06:20 +00:00
|
|
|
}
|
|
|
|
#else
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int page_cpupid_last(struct page *page)
|
2013-02-23 00:34:32 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
|
2013-02-23 00:34:32 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
extern int page_cpupid_xchg_last(struct page *page, int cpupid);
|
2013-02-23 00:34:32 +00:00
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline void page_cpupid_reset_last(struct page *page)
|
2013-02-23 00:34:32 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
int cpupid = (1 << LAST_CPUPID_SHIFT) - 1;
|
2013-02-23 00:34:46 +00:00
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
page->flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
|
|
|
|
page->flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
|
2013-02-23 00:34:32 +00:00
|
|
|
}
|
2013-10-07 10:29:20 +00:00
|
|
|
#endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
|
|
|
|
#else /* !CONFIG_NUMA_BALANCING */
|
|
|
|
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return page_to_nid(page); /* XXX */
|
2012-11-12 09:06:20 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int page_cpupid_last(struct page *page)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
2013-10-07 10:29:20 +00:00
|
|
|
return page_to_nid(page); /* XXX */
|
2012-11-12 09:06:20 +00:00
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_nid(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_pid(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpupid_to_cpu(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline int cpu_pid_to_cpupid(int nid, int pid)
|
|
|
|
{
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline bool cpupid_pid_unset(int cpupid)
|
2013-10-07 10:29:07 +00:00
|
|
|
{
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
2013-10-07 10:29:20 +00:00
|
|
|
static inline void page_cpupid_reset_last(struct page *page)
|
2012-11-12 09:06:20 +00:00
|
|
|
{
|
|
|
|
}
|
2013-10-07 10:29:21 +00:00
|
|
|
|
|
|
|
static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
|
|
|
|
{
|
|
|
|
return false;
|
|
|
|
}
|
2013-10-07 10:29:20 +00:00
|
|
|
#endif /* CONFIG_NUMA_BALANCING */
|
2012-11-12 09:06:20 +00:00
|
|
|
|
2011-07-26 00:11:51 +00:00
|
|
|
static inline struct zone *page_zone(const struct page *page)
|
2006-12-07 04:31:45 +00:00
|
|
|
{
|
|
|
|
return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
|
|
|
|
}
|
|
|
|
|
2013-02-23 00:35:21 +00:00
|
|
|
#ifdef SECTION_IN_PAGE_FLAGS
|
2011-05-25 00:12:32 +00:00
|
|
|
static inline void set_page_section(struct page *page, unsigned long section)
|
|
|
|
{
|
|
|
|
page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
|
|
|
|
page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
|
|
|
|
}
|
|
|
|
|
2011-08-17 16:40:33 +00:00
|
|
|
static inline unsigned long page_to_section(const struct page *page)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
{
|
|
|
|
return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
|
|
|
|
}
|
2008-04-28 09:12:43 +00:00
|
|
|
#endif
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
|
2006-09-26 06:31:13 +00:00
|
|
|
static inline void set_page_zone(struct page *page, enum zone_type zone)
|
2005-06-23 07:07:40 +00:00
|
|
|
{
|
|
|
|
page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
|
|
|
|
page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
|
|
|
|
}
|
2006-09-26 06:31:13 +00:00
|
|
|
|
2005-06-23 07:07:40 +00:00
|
|
|
static inline void set_page_node(struct page *page, unsigned long node)
|
|
|
|
{
|
|
|
|
page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
|
|
|
|
page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
2006-12-07 04:31:45 +00:00
|
|
|
|
2006-09-26 06:31:13 +00:00
|
|
|
static inline void set_page_links(struct page *page, enum zone_type zone,
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
unsigned long node, unsigned long pfn)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2005-06-23 07:07:40 +00:00
|
|
|
set_page_zone(page, zone);
|
|
|
|
set_page_node(page, node);
|
2013-02-23 00:35:21 +00:00
|
|
|
#ifdef SECTION_IN_PAGE_FLAGS
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
set_page_section(page, pfn_to_section_nr(pfn));
|
2011-05-25 00:12:32 +00:00
|
|
|
#endif
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2006-06-30 08:55:32 +00:00
|
|
|
/*
|
|
|
|
* Some inline functions in vmstat.h depend on page_zone()
|
|
|
|
*/
|
|
|
|
#include <linux/vmstat.h>
|
|
|
|
|
2011-07-26 00:11:51 +00:00
|
|
|
static __always_inline void *lowmem_page_address(const struct page *page)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2011-08-17 16:40:33 +00:00
|
|
|
return __va(PFN_PHYS(page_to_pfn(page)));
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
|
|
|
|
#define HASHED_PAGE_VIRTUAL
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if defined(WANT_PAGE_VIRTUAL)
|
2014-01-21 23:48:47 +00:00
|
|
|
static inline void *page_address(const struct page *page)
|
|
|
|
{
|
|
|
|
return page->virtual;
|
|
|
|
}
|
|
|
|
static inline void set_page_address(struct page *page, void *address)
|
|
|
|
{
|
|
|
|
page->virtual = address;
|
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
#define page_address_init() do { } while(0)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if defined(HASHED_PAGE_VIRTUAL)
|
2011-08-17 12:45:09 +00:00
|
|
|
void *page_address(const struct page *page);
|
2005-04-16 22:20:36 +00:00
|
|
|
void set_page_address(struct page *page, void *virtual);
|
|
|
|
void page_address_init(void);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
|
|
|
|
#define page_address(page) lowmem_page_address(page)
|
|
|
|
#define set_page_address(page, address) do { } while(0)
|
|
|
|
#define page_address_init() do { } while(0)
|
|
|
|
#endif
|
|
|
|
|
2015-04-15 23:14:53 +00:00
|
|
|
extern void *page_rmapping(struct page *page);
|
|
|
|
extern struct anon_vma *page_anon_vma(struct page *page);
|
2013-02-23 00:34:35 +00:00
|
|
|
extern struct address_space *page_mapping(struct page *page);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2012-07-31 23:44:47 +00:00
|
|
|
extern struct address_space *__page_file_mapping(struct page *);
|
|
|
|
|
|
|
|
static inline
|
|
|
|
struct address_space *page_file_mapping(struct page *page)
|
|
|
|
{
|
|
|
|
if (unlikely(PageSwapCache(page)))
|
|
|
|
return __page_file_mapping(page);
|
|
|
|
|
|
|
|
return page->mapping;
|
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* Return the pagecache index of the passed page. Regular pagecache pages
|
|
|
|
* use ->index whereas swapcache pages use ->private
|
|
|
|
*/
|
|
|
|
static inline pgoff_t page_index(struct page *page)
|
|
|
|
{
|
|
|
|
if (unlikely(PageSwapCache(page)))
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
return page_private(page);
|
2005-04-16 22:20:36 +00:00
|
|
|
return page->index;
|
|
|
|
}
|
|
|
|
|
2012-07-31 23:44:47 +00:00
|
|
|
extern pgoff_t __page_file_index(struct page *page);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Return the file index of the page. Regular pagecache pages use ->index
|
|
|
|
* whereas swapcache pages use swp_offset(->private)
|
|
|
|
*/
|
|
|
|
static inline pgoff_t page_file_index(struct page *page)
|
|
|
|
{
|
|
|
|
if (unlikely(PageSwapCache(page)))
|
|
|
|
return __page_file_index(page);
|
|
|
|
|
|
|
|
return page->index;
|
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* Return true if this page is mapped into pagetables.
|
|
|
|
*/
|
|
|
|
static inline int page_mapped(struct page *page)
|
|
|
|
{
|
|
|
|
return atomic_read(&(page)->_mapcount) >= 0;
|
|
|
|
}
|
|
|
|
|
2015-08-21 21:11:51 +00:00
|
|
|
/*
|
|
|
|
* Return true only if the page has been allocated with
|
|
|
|
* ALLOC_NO_WATERMARKS and the low watermark was not
|
|
|
|
* met implying that the system is under some pressure.
|
|
|
|
*/
|
|
|
|
static inline bool page_is_pfmemalloc(struct page *page)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Page index cannot be this large so this must be
|
|
|
|
* a pfmemalloc page.
|
|
|
|
*/
|
|
|
|
return page->index == -1UL;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Only to be called by the page allocator on a freshly allocated
|
|
|
|
* page.
|
|
|
|
*/
|
|
|
|
static inline void set_page_pfmemalloc(struct page *page)
|
|
|
|
{
|
|
|
|
page->index = -1UL;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void clear_page_pfmemalloc(struct page *page)
|
|
|
|
{
|
|
|
|
page->index = 0;
|
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* Different kinds of faults, as returned by handle_mm_fault().
|
|
|
|
* Used to decide whether a process gets delivered SIGBUS or
|
|
|
|
* just gets major/minor fault counters bumped up.
|
|
|
|
*/
|
2007-07-19 08:47:03 +00:00
|
|
|
|
2007-07-19 08:47:05 +00:00
|
|
|
#define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */
|
2007-07-19 08:47:03 +00:00
|
|
|
|
2007-07-19 08:47:05 +00:00
|
|
|
#define VM_FAULT_OOM 0x0001
|
|
|
|
#define VM_FAULT_SIGBUS 0x0002
|
|
|
|
#define VM_FAULT_MAJOR 0x0004
|
|
|
|
#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
|
2010-10-06 19:45:00 +00:00
|
|
|
#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
|
|
|
|
#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */
|
vm: add VM_FAULT_SIGSEGV handling support
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29 18:51:32 +00:00
|
|
|
#define VM_FAULT_SIGSEGV 0x0040
|
[PATCH] fix get_user_pages bug
Checking pte_dirty instead of pte_write in __follow_page is problematic
for s390, and for copy_one_pte which leaves dirty when clearing write.
So revert __follow_page to check pte_write as before, and make
do_wp_page pass back a special extra VM_FAULT_WRITE bit to say it has
done its full job: once get_user_pages receives this value, it no longer
requires pte_write in __follow_page.
But most callers of handle_mm_fault, in the various architectures, have
switch statements which do not expect this new case. To avoid changing
them all in a hurry, make an inline wrapper function (using the old
name) that masks off the new bit, and use the extended interface with
double underscores.
Yes, we do have a call to do_wp_page from do_swap_page, but no need to
change that: in rare case it's needed, another do_wp_page will follow.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
[ Cleanups by Nick Piggin ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-03 10:24:01 +00:00
|
|
|
|
2007-07-19 08:47:05 +00:00
|
|
|
#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
|
|
|
|
#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
|
2010-10-26 21:21:57 +00:00
|
|
|
#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
|
2013-09-12 22:14:05 +00:00
|
|
|
#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to small */
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2010-10-06 19:45:00 +00:00
|
|
|
#define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */
|
|
|
|
|
vm: add VM_FAULT_SIGSEGV handling support
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29 18:51:32 +00:00
|
|
|
#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
|
|
|
|
VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
|
|
|
|
VM_FAULT_FALLBACK)
|
2010-10-06 19:45:00 +00:00
|
|
|
|
|
|
|
/* Encode hstate index for a hwpoisoned large page */
|
|
|
|
#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
|
|
|
|
#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
|
2007-07-19 08:47:03 +00:00
|
|
|
|
2009-01-06 22:38:59 +00:00
|
|
|
/*
|
|
|
|
* Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
|
|
|
|
*/
|
|
|
|
extern void pagefault_out_of_memory(void);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
|
|
|
|
|
2011-03-22 23:30:46 +00:00
|
|
|
/*
|
2011-05-25 00:11:16 +00:00
|
|
|
* Flags passed to show_mem() and show_free_areas() to suppress output in
|
2011-03-22 23:30:46 +00:00
|
|
|
* various contexts.
|
|
|
|
*/
|
2013-04-29 22:06:11 +00:00
|
|
|
#define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
|
2011-03-22 23:30:46 +00:00
|
|
|
|
2011-05-25 00:11:16 +00:00
|
|
|
extern void show_free_areas(unsigned int flags);
|
|
|
|
extern bool skip_free_areas_node(unsigned int flags, int nid);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
int shmem_zero_setup(struct vm_area_struct *);
|
2014-04-03 21:47:46 +00:00
|
|
|
#ifdef CONFIG_SHMEM
|
|
|
|
bool shmem_mapping(struct address_space *mapping);
|
|
|
|
#else
|
|
|
|
static inline bool shmem_mapping(struct address_space *mapping)
|
|
|
|
{
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
#endif
|
2005-04-16 22:20:36 +00:00
|
|
|
|
Detach sched.h from mm.h
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-20 21:22:52 +00:00
|
|
|
extern int can_do_mlock(void);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern int user_shm_lock(size_t, struct user_struct *);
|
|
|
|
extern void user_shm_unlock(size_t, struct user_struct *);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Parameter block passed down to zap_pte_range in exceptional cases.
|
|
|
|
*/
|
|
|
|
struct zap_details {
|
|
|
|
struct address_space *check_mapping; /* Check page->mapping if set */
|
|
|
|
pgoff_t first_index; /* Lowest page->index to unmap */
|
|
|
|
pgoff_t last_index; /* Highest page->index to unmap */
|
|
|
|
};
|
|
|
|
|
mm: introduce pte_special pte bit
s390 for one, cannot implement VM_MIXEDMAP with pfn_valid, due to their memory
model (which is more dynamic than most). Instead, they had proposed to
implement it with an additional path through vm_normal_page(), using a bit in
the pte to determine whether or not the page should be refcounted:
vm_normal_page()
{
...
if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma->vm_flags & VM_MIXEDMAP) {
#ifdef s390
if (!mixedmap_refcount_pte(pte))
return NULL;
#else
if (!pfn_valid(pfn))
return NULL;
#endif
goto out;
}
...
}
This is fine, however if we are allowed to use a bit in the pte to determine
refcountedness, we can use that to _completely_ replace all the vma based
schemes. So instead of adding more cases to the already complex vma-based
scheme, we can have a clearly seperate and simple pte-based scheme (and get
slightly better code generation in the process):
vm_normal_page()
{
#ifdef s390
if (!mixedmap_refcount_pte(pte))
return NULL;
return pte_page(pte);
#else
...
#endif
}
And finally, we may rather make this concept usable by any architecture rather
than making it s390 only, so implement a new type of pte state for this.
Unfortunately the old vma based code must stay, because some architectures may
not be able to spare pte bits. This makes vm_normal_page a little bit more
ugly than we would like, but the 2 cases are clearly seperate.
So introduce a pte_special pte state, and use it in mm/memory.c. It is
currently a noop for all architectures, so this doesn't actually result in any
compiled code changes to mm/memory.o.
BTW:
I haven't put vm_normal_page() into arch code as-per an earlier suggestion.
The reason is that, regardless of where vm_normal_page is actually
implemented, the *abstraction* is still exactly the same. Also, while it
depends on whether the architecture has pte_special or not, that is the
only two possible cases, and it really isn't an arch specific function --
the role of the arch code should be to provide primitive functions and
accessors with which to build the core code; pte_special does that. We do
not want architectures to know or care about vm_normal_page itself, and
we definitely don't want them being able to invent something new there
out of sight of mm/ code. If we made vm_normal_page an arch function, then
we have to make vm_insert_mixed (next patch) an arch function too. So I
don't think moving it to arch code fundamentally improves any abstractions,
while it does practically make the code more difficult to follow, for both
mm and arch developers, and easier to misuse.
[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:13:00 +00:00
|
|
|
struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
|
|
|
|
pte_t pte);
|
|
|
|
|
2008-07-30 05:33:53 +00:00
|
|
|
int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
|
|
|
|
unsigned long size);
|
2012-03-05 18:38:09 +00:00
|
|
|
void zap_page_range(struct vm_area_struct *vma, unsigned long address,
|
2005-04-16 22:20:36 +00:00
|
|
|
unsigned long size, struct zap_details *);
|
2012-05-06 20:54:06 +00:00
|
|
|
void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
|
|
|
|
unsigned long start, unsigned long end);
|
2008-02-05 06:29:01 +00:00
|
|
|
|
|
|
|
/**
|
|
|
|
* mm_walk - callbacks for walk_page_range
|
|
|
|
* @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
|
2011-03-22 23:32:56 +00:00
|
|
|
* this handler is required to be able to handle
|
|
|
|
* pmd_trans_huge() pmds. They may simply choose to
|
|
|
|
* split_huge_page() instead of handling it explicitly.
|
2008-02-05 06:29:01 +00:00
|
|
|
* @pte_entry: if set, called for each non-empty PTE (4th-level) entry
|
|
|
|
* @pte_hole: if set, called for each hole at all levels
|
mm hugetlb: add hugepage support to pagemap
This patch enables extraction of the pfn of a hugepage from
/proc/pid/pagemap in an architecture independent manner.
Details
-------
My test program (leak_pagemap) works as follows:
- creat() and mmap() a file on hugetlbfs (file size is 200MB == 100 hugepages,)
- read()/write() something on it,
- call page-types with option -p,
- munmap() and unlink() the file on hugetlbfs
Without my patches
------------------
$ ./leak_pagemap
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000000 1 0 __________________________________
0x0000000000000804 1 0 __R________M______________________ referenced,mmap
0x000000000000086c 81 0 __RU_lA____M______________________ referenced,uptodate,lru,active,mmap
0x0000000000005808 5 0 ___U_______Ma_b___________________ uptodate,mmap,anonymous,swapbacked
0x0000000000005868 12 0 ___U_lA____Ma_b___________________ uptodate,lru,active,mmap,anonymous,swapbacked
0x000000000000586c 1 0 __RU_lA____Ma_b___________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
total 101 0
The output of page-types don't show any hugepage.
With my patches
---------------
$ ./leak_pagemap
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000000 1 0 __________________________________
0x0000000000030000 51100 199 ________________TG________________ compound_tail,huge
0x0000000000028018 100 0 ___UD__________H_G________________ uptodate,dirty,compound_head,huge
0x0000000000000804 1 0 __R________M______________________ referenced,mmap
0x000000000000080c 1 0 __RU_______M______________________ referenced,uptodate,mmap
0x000000000000086c 80 0 __RU_lA____M______________________ referenced,uptodate,lru,active,mmap
0x0000000000005808 4 0 ___U_______Ma_b___________________ uptodate,mmap,anonymous,swapbacked
0x0000000000005868 12 0 ___U_lA____Ma_b___________________ uptodate,lru,active,mmap,anonymous,swapbacked
0x000000000000586c 1 0 __RU_lA____Ma_b___________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
total 51300 200
The output of page-types shows 51200 pages contributing to hugepages,
containing 100 head pages and 51100 tail pages as expected.
[akpm@linux-foundation.org: build fix]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 02:00:01 +00:00
|
|
|
* @hugetlb_entry: if set, called for each hugetlb entry
|
2015-02-11 23:27:37 +00:00
|
|
|
* @test_walk: caller specific callback function to determine whether
|
|
|
|
* we walk over the current vma or not. A positive returned
|
|
|
|
* value means "do page table walk over the current vma,"
|
|
|
|
* and a negative one means "abort current page table walk
|
|
|
|
* right now." 0 means "skip the current vma."
|
|
|
|
* @mm: mm_struct representing the target process of page table walk
|
|
|
|
* @vma: vma currently walked (NULL if walking outside vmas)
|
|
|
|
* @private: private data for callbacks' usage
|
2008-02-05 06:29:01 +00:00
|
|
|
*
|
2015-02-11 23:27:37 +00:00
|
|
|
* (see the comment on walk_page_range() for more details)
|
2008-02-05 06:29:01 +00:00
|
|
|
*/
|
|
|
|
struct mm_walk {
|
2013-05-07 23:18:10 +00:00
|
|
|
int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
|
|
|
|
unsigned long next, struct mm_walk *walk);
|
|
|
|
int (*pte_entry)(pte_t *pte, unsigned long addr,
|
|
|
|
unsigned long next, struct mm_walk *walk);
|
|
|
|
int (*pte_hole)(unsigned long addr, unsigned long next,
|
|
|
|
struct mm_walk *walk);
|
|
|
|
int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
|
|
|
|
unsigned long addr, unsigned long next,
|
|
|
|
struct mm_walk *walk);
|
2015-02-11 23:27:37 +00:00
|
|
|
int (*test_walk)(unsigned long addr, unsigned long next,
|
|
|
|
struct mm_walk *walk);
|
2008-06-12 22:21:47 +00:00
|
|
|
struct mm_struct *mm;
|
2015-02-11 23:27:37 +00:00
|
|
|
struct vm_area_struct *vma;
|
2008-06-12 22:21:47 +00:00
|
|
|
void *private;
|
2008-02-05 06:29:01 +00:00
|
|
|
};
|
|
|
|
|
2008-06-12 22:21:47 +00:00
|
|
|
int walk_page_range(unsigned long addr, unsigned long end,
|
|
|
|
struct mm_walk *walk);
|
2015-02-11 23:27:40 +00:00
|
|
|
int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk);
|
2008-07-24 04:27:10 +00:00
|
|
|
void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
|
2005-04-19 20:29:16 +00:00
|
|
|
unsigned long end, unsigned long floor, unsigned long ceiling);
|
2005-04-16 22:20:36 +00:00
|
|
|
int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
|
|
|
|
struct vm_area_struct *vma);
|
|
|
|
void unmap_mapping_range(struct address_space *mapping,
|
|
|
|
loff_t const holebegin, loff_t const holelen, int even_cows);
|
2009-06-16 22:32:35 +00:00
|
|
|
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
|
|
|
|
unsigned long *pfn);
|
2008-12-19 21:47:27 +00:00
|
|
|
int follow_phys(struct vm_area_struct *vma, unsigned long address,
|
|
|
|
unsigned int flags, unsigned long *prot, resource_size_t *phys);
|
2008-07-24 04:27:05 +00:00
|
|
|
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
|
|
|
|
void *buf, int len, int write);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
static inline void unmap_shared_mapping_range(struct address_space *mapping,
|
|
|
|
loff_t const holebegin, loff_t const holelen)
|
|
|
|
{
|
|
|
|
unmap_mapping_range(mapping, holebegin, holelen, 0);
|
|
|
|
}
|
|
|
|
|
2013-09-12 22:13:56 +00:00
|
|
|
extern void truncate_pagecache(struct inode *inode, loff_t new);
|
2010-06-04 09:30:04 +00:00
|
|
|
extern void truncate_setsize(struct inode *inode, loff_t newsize);
|
vfs: fix data corruption when blocksize < pagesize for mmaped data
->page_mkwrite() is used by filesystems to allocate blocks under a page
which is becoming writeably mmapped in some process' address space. This
allows a filesystem to return a page fault if there is not enough space
available, user exceeds quota or similar problem happens, rather than
silently discarding data later when writepage is called.
However VFS fails to call ->page_mkwrite() in all the cases where
filesystems need it when blocksize < pagesize. For example when
blocksize = 1024, pagesize = 4096 the following is problematic:
ftruncate(fd, 0);
pwrite(fd, buf, 1024, 0);
map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0);
map[0] = 'a'; ----> page_mkwrite() for index 0 is called
ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */
mremap(map, 1024, 10000, 0);
map[4095] = 'a'; ----> no page_mkwrite() called
At the moment ->page_mkwrite() is called, filesystem can allocate only
one block for the page because i_size == 1024. Otherwise it would create
blocks beyond i_size which is generally undesirable. But later at
->writepage() time, we also need to store data at offset 4095 but we
don't have block allocated for it.
This patch introduces a helper function filesystems can use to have
->page_mkwrite() called at all the necessary moments.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-10-02 01:49:18 +00:00
|
|
|
void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
|
2012-03-28 21:42:40 +00:00
|
|
|
void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
|
2009-09-16 09:50:12 +00:00
|
|
|
int truncate_inode_page(struct address_space *mapping, struct page *page);
|
2009-09-16 09:50:13 +00:00
|
|
|
int generic_error_remove_page(struct address_space *mapping, struct page *page);
|
2009-09-16 09:50:13 +00:00
|
|
|
int invalidate_inode_page(struct page *page);
|
|
|
|
|
2006-01-06 08:11:44 +00:00
|
|
|
#ifdef CONFIG_MMU
|
2007-07-19 08:47:05 +00:00
|
|
|
extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
|
2009-04-10 16:01:23 +00:00
|
|
|
unsigned long address, unsigned int flags);
|
2011-07-27 10:17:11 +00:00
|
|
|
extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long address, unsigned int fault_flags);
|
2006-01-06 08:11:44 +00:00
|
|
|
#else
|
|
|
|
static inline int handle_mm_fault(struct mm_struct *mm,
|
|
|
|
struct vm_area_struct *vma, unsigned long address,
|
2009-04-10 16:01:23 +00:00
|
|
|
unsigned int flags)
|
2006-01-06 08:11:44 +00:00
|
|
|
{
|
|
|
|
/* should never happen if there's no MMU */
|
|
|
|
BUG();
|
|
|
|
return VM_FAULT_SIGBUS;
|
|
|
|
}
|
2011-07-27 10:17:11 +00:00
|
|
|
static inline int fixup_user_fault(struct task_struct *tsk,
|
|
|
|
struct mm_struct *mm, unsigned long address,
|
|
|
|
unsigned int fault_flags)
|
|
|
|
{
|
|
|
|
/* should never happen if there's no MMU */
|
|
|
|
BUG();
|
|
|
|
return -EFAULT;
|
|
|
|
}
|
2006-01-06 08:11:44 +00:00
|
|
|
#endif
|
[PATCH] fix get_user_pages bug
Checking pte_dirty instead of pte_write in __follow_page is problematic
for s390, and for copy_one_pte which leaves dirty when clearing write.
So revert __follow_page to check pte_write as before, and make
do_wp_page pass back a special extra VM_FAULT_WRITE bit to say it has
done its full job: once get_user_pages receives this value, it no longer
requires pte_write in __follow_page.
But most callers of handle_mm_fault, in the various architectures, have
switch statements which do not expect this new case. To avoid changing
them all in a hurry, make an inline wrapper function (using the old
name) that masks off the new bit, and use the extended interface with
double underscores.
Yes, we do have a call to do_wp_page from do_swap_page, but no need to
change that: in rare case it's needed, another do_wp_page will follow.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
[ Cleanups by Nick Piggin ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-03 10:24:01 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write);
|
2011-03-13 19:49:20 +00:00
|
|
|
extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
|
|
|
|
void *buf, int len, int write);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2013-02-23 00:35:55 +00:00
|
|
|
long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long start, unsigned long nr_pages,
|
|
|
|
unsigned int foll_flags, struct page **pages,
|
|
|
|
struct vm_area_struct **vmas, int *nonblocking);
|
|
|
|
long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long start, unsigned long nr_pages,
|
|
|
|
int write, int force, struct page **pages,
|
|
|
|
struct vm_area_struct **vmas);
|
mm: gup: add get_user_pages_locked and get_user_pages_unlocked
FAULT_FOLL_ALLOW_RETRY allows the page fault to drop the mmap_sem for
reading to reduce the mmap_sem contention (for writing), like while
waiting for I/O completion. The problem is that right now practically no
get_user_pages call uses FAULT_FOLL_ALLOW_RETRY, so we're not leveraging
that nifty feature.
Andres fixed it for the KVM page fault. However get_user_pages_fast
remains uncovered, and 99% of other get_user_pages aren't using it either
(the only exception being FOLL_NOWAIT in KVM which is really nonblocking
and in fact it doesn't even release the mmap_sem).
So this patchsets extends the optimization Andres did in the KVM page
fault to the whole kernel. It makes most important places (including
gup_fast) to use FAULT_FOLL_ALLOW_RETRY to reduce the mmap_sem hold times
during I/O.
The only few places that remains uncovered are drivers like v4l and other
exceptions that tends to work on their own memory and they're not working
on random user memory (for example like O_DIRECT that uses gup_fast and is
fully covered by this patch).
A follow up patch should probably also add a printk_once warning to
get_user_pages that should go obsolete and be phased out eventually. The
"vmas" parameter of get_user_pages makes it fundamentally incompatible
with FAULT_FOLL_ALLOW_RETRY (vmas array becomes meaningless the moment the
mmap_sem is released).
While this is just an optimization, this becomes an absolute requirement
for the userfaultfd feature http://lwn.net/Articles/615086/ .
The userfaultfd allows to block the page fault, and in order to do so I
need to drop the mmap_sem first. So this patch also ensures that all
memory where userfaultfd could be registered by KVM, the very first fault
(no matter if it is a regular page fault, or a get_user_pages) always has
FAULT_FOLL_ALLOW_RETRY set. Then the userfaultfd blocks and it is waken
only when the pagetable is already mapped. The second fault attempt after
the wakeup doesn't need FAULT_FOLL_ALLOW_RETRY, so it's ok to retry
without it.
This patch (of 5):
We can leverage the VM_FAULT_RETRY functionality in the page fault paths
better by using either get_user_pages_locked or get_user_pages_unlocked.
The former allows conversion of get_user_pages invocations that will have
to pass a "&locked" parameter to know if the mmap_sem was dropped during
the call. Example from:
down_read(&mm->mmap_sem);
do_something()
get_user_pages(tsk, mm, ..., pages, NULL);
up_read(&mm->mmap_sem);
to:
int locked = 1;
down_read(&mm->mmap_sem);
do_something()
get_user_pages_locked(tsk, mm, ..., pages, &locked);
if (locked)
up_read(&mm->mmap_sem);
The latter is suitable only as a drop in replacement of the form:
down_read(&mm->mmap_sem);
get_user_pages(tsk, mm, ..., pages, NULL);
up_read(&mm->mmap_sem);
into:
get_user_pages_unlocked(tsk, mm, ..., pages);
Where tsk, mm, the intermediate "..." paramters and "pages" can be any
value as before. Just the last parameter of get_user_pages (vmas) must be
NULL for get_user_pages_locked|unlocked to be usable (the latter original
form wouldn't have been safe anyway if vmas wasn't null, for the former we
just make it explicit by dropping the parameter).
If vmas is not NULL these two methods cannot be used.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com>
Reviewed-by: Peter Feiner <pfeiner@google.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:27:17 +00:00
|
|
|
long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long start, unsigned long nr_pages,
|
|
|
|
int write, int force, struct page **pages,
|
|
|
|
int *locked);
|
2015-02-11 23:27:20 +00:00
|
|
|
long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long start, unsigned long nr_pages,
|
|
|
|
int write, int force, struct page **pages,
|
|
|
|
unsigned int gup_flags);
|
mm: gup: add get_user_pages_locked and get_user_pages_unlocked
FAULT_FOLL_ALLOW_RETRY allows the page fault to drop the mmap_sem for
reading to reduce the mmap_sem contention (for writing), like while
waiting for I/O completion. The problem is that right now practically no
get_user_pages call uses FAULT_FOLL_ALLOW_RETRY, so we're not leveraging
that nifty feature.
Andres fixed it for the KVM page fault. However get_user_pages_fast
remains uncovered, and 99% of other get_user_pages aren't using it either
(the only exception being FOLL_NOWAIT in KVM which is really nonblocking
and in fact it doesn't even release the mmap_sem).
So this patchsets extends the optimization Andres did in the KVM page
fault to the whole kernel. It makes most important places (including
gup_fast) to use FAULT_FOLL_ALLOW_RETRY to reduce the mmap_sem hold times
during I/O.
The only few places that remains uncovered are drivers like v4l and other
exceptions that tends to work on their own memory and they're not working
on random user memory (for example like O_DIRECT that uses gup_fast and is
fully covered by this patch).
A follow up patch should probably also add a printk_once warning to
get_user_pages that should go obsolete and be phased out eventually. The
"vmas" parameter of get_user_pages makes it fundamentally incompatible
with FAULT_FOLL_ALLOW_RETRY (vmas array becomes meaningless the moment the
mmap_sem is released).
While this is just an optimization, this becomes an absolute requirement
for the userfaultfd feature http://lwn.net/Articles/615086/ .
The userfaultfd allows to block the page fault, and in order to do so I
need to drop the mmap_sem first. So this patch also ensures that all
memory where userfaultfd could be registered by KVM, the very first fault
(no matter if it is a regular page fault, or a get_user_pages) always has
FAULT_FOLL_ALLOW_RETRY set. Then the userfaultfd blocks and it is waken
only when the pagetable is already mapped. The second fault attempt after
the wakeup doesn't need FAULT_FOLL_ALLOW_RETRY, so it's ok to retry
without it.
This patch (of 5):
We can leverage the VM_FAULT_RETRY functionality in the page fault paths
better by using either get_user_pages_locked or get_user_pages_unlocked.
The former allows conversion of get_user_pages invocations that will have
to pass a "&locked" parameter to know if the mmap_sem was dropped during
the call. Example from:
down_read(&mm->mmap_sem);
do_something()
get_user_pages(tsk, mm, ..., pages, NULL);
up_read(&mm->mmap_sem);
to:
int locked = 1;
down_read(&mm->mmap_sem);
do_something()
get_user_pages_locked(tsk, mm, ..., pages, &locked);
if (locked)
up_read(&mm->mmap_sem);
The latter is suitable only as a drop in replacement of the form:
down_read(&mm->mmap_sem);
get_user_pages(tsk, mm, ..., pages, NULL);
up_read(&mm->mmap_sem);
into:
get_user_pages_unlocked(tsk, mm, ..., pages);
Where tsk, mm, the intermediate "..." paramters and "pages" can be any
value as before. Just the last parameter of get_user_pages (vmas) must be
NULL for get_user_pages_locked|unlocked to be usable (the latter original
form wouldn't have been safe anyway if vmas wasn't null, for the former we
just make it explicit by dropping the parameter).
If vmas is not NULL these two methods cannot be used.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com>
Reviewed-by: Peter Feiner <pfeiner@google.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:27:17 +00:00
|
|
|
long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
|
|
|
|
unsigned long start, unsigned long nr_pages,
|
|
|
|
int write, int force, struct page **pages);
|
2009-06-16 22:31:39 +00:00
|
|
|
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
|
|
|
|
struct page **pages);
|
2012-07-31 23:44:51 +00:00
|
|
|
struct kvec;
|
|
|
|
int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
|
|
|
|
struct page **pages);
|
|
|
|
int get_kernel_page(unsigned long start, int write, struct page **pages);
|
2009-09-22 00:03:25 +00:00
|
|
|
struct page *get_dump_page(unsigned long addr);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-08-29 18:05:54 +00:00
|
|
|
extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
|
2013-05-22 03:17:23 +00:00
|
|
|
extern void do_invalidatepage(struct page *page, unsigned int offset,
|
|
|
|
unsigned int length);
|
2006-08-29 18:05:54 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
int __set_page_dirty_nobuffers(struct page *page);
|
2007-02-10 09:43:15 +00:00
|
|
|
int __set_page_dirty_no_writeback(struct page *page);
|
2005-04-16 22:20:36 +00:00
|
|
|
int redirty_page_for_writepage(struct writeback_control *wbc,
|
|
|
|
struct page *page);
|
memcg: add per cgroup dirty page accounting
When modifying PG_Dirty on cached file pages, update the new
MEM_CGROUP_STAT_DIRTY counter. This is done in the same places where
global NR_FILE_DIRTY is managed. The new memcg stat is visible in the
per memcg memory.stat cgroupfs file. The most recent past attempt at
this was http://thread.gmane.org/gmane.linux.kernel.cgroups/8632
The new accounting supports future efforts to add per cgroup dirty
page throttling and writeback. It also helps an administrator break
down a container's memory usage and provides evidence to understand
memcg oom kills (the new dirty count is included in memcg oom kill
messages).
The ability to move page accounting between memcg
(memory.move_charge_at_immigrate) makes this accounting more
complicated than the global counter. The existing
mem_cgroup_{begin,end}_page_stat() lock is used to serialize move
accounting with stat updates.
Typical update operation:
memcg = mem_cgroup_begin_page_stat(page)
if (TestSetPageDirty()) {
[...]
mem_cgroup_update_page_stat(memcg)
}
mem_cgroup_end_page_stat(memcg)
Summary of mem_cgroup_end_page_stat() overhead:
- Without CONFIG_MEMCG it's a no-op
- With CONFIG_MEMCG and no inter memcg task movement, it's just
rcu_read_lock()
- With CONFIG_MEMCG and inter memcg task movement, it's
rcu_read_lock() + spin_lock_irqsave()
A memcg parameter is added to several routines because their callers
now grab mem_cgroup_begin_page_stat() which returns the memcg later
needed by for mem_cgroup_update_page_stat().
Because mem_cgroup_begin_page_stat() may disable interrupts, some
adjustments are needed:
- move __mark_inode_dirty() from __set_page_dirty() to its caller.
__mark_inode_dirty() locking does not want interrupts disabled.
- use spin_lock_irqsave(tree_lock) rather than spin_lock_irq() in
__delete_from_page_cache(), replace_page_cache_page(),
invalidate_complete_page2(), and __remove_mapping().
text data bss dec hex filename
8925147 1774832 1785856 12485835 be84cb vmlinux-!CONFIG_MEMCG-before
8925339 1774832 1785856 12486027 be858b vmlinux-!CONFIG_MEMCG-after
+192 text bytes
8965977 1784992 1785856 12536825 bf4bf9 vmlinux-CONFIG_MEMCG-before
8966750 1784992 1785856 12537598 bf4efe vmlinux-CONFIG_MEMCG-after
+773 text bytes
Performance tests run on v4.0-rc1-36-g4f671fe2f952. Lower is better for
all metrics, they're all wall clock or cycle counts. The read and write
fault benchmarks just measure fault time, they do not include I/O time.
* CONFIG_MEMCG not set:
baseline patched
kbuild 1m25.030000(+-0.088% 3 samples) 1m25.426667(+-0.120% 3 samples)
dd write 100 MiB 0.859211561 +-15.10% 0.874162885 +-15.03%
dd write 200 MiB 1.670653105 +-17.87% 1.669384764 +-11.99%
dd write 1000 MiB 8.434691190 +-14.15% 8.474733215 +-14.77%
read fault cycles 254.0(+-0.000% 10 samples) 253.0(+-0.000% 10 samples)
write fault cycles 2021.2(+-3.070% 10 samples) 1984.5(+-1.036% 10 samples)
* CONFIG_MEMCG=y root_memcg:
baseline patched
kbuild 1m25.716667(+-0.105% 3 samples) 1m25.686667(+-0.153% 3 samples)
dd write 100 MiB 0.855650830 +-14.90% 0.887557919 +-14.90%
dd write 200 MiB 1.688322953 +-12.72% 1.667682724 +-13.33%
dd write 1000 MiB 8.418601605 +-14.30% 8.673532299 +-15.00%
read fault cycles 266.0(+-0.000% 10 samples) 266.0(+-0.000% 10 samples)
write fault cycles 2051.7(+-1.349% 10 samples) 2049.6(+-1.686% 10 samples)
* CONFIG_MEMCG=y non-root_memcg:
baseline patched
kbuild 1m26.120000(+-0.273% 3 samples) 1m25.763333(+-0.127% 3 samples)
dd write 100 MiB 0.861723964 +-15.25% 0.818129350 +-14.82%
dd write 200 MiB 1.669887569 +-13.30% 1.698645885 +-13.27%
dd write 1000 MiB 8.383191730 +-14.65% 8.351742280 +-14.52%
read fault cycles 265.7(+-0.172% 10 samples) 267.0(+-0.000% 10 samples)
write fault cycles 2070.6(+-1.512% 10 samples) 2084.4(+-2.148% 10 samples)
As expected anon page faults are not affected by this patch.
tj: Updated to apply on top of the recent cancel_dirty_page() changes.
Signed-off-by: Sha Zhengju <handai.szj@gmail.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 21:13:16 +00:00
|
|
|
void account_page_dirtied(struct page *page, struct address_space *mapping,
|
|
|
|
struct mem_cgroup *memcg);
|
|
|
|
void account_page_cleaned(struct page *page, struct address_space *mapping,
|
writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
The mechanism for detecting whether an inode should switch its wb
(bdi_writeback) association is now in place. This patch build the
framework for the actual switching.
This patch adds a new inode flag I_WB_SWITCHING, which has two
functions. First, the easy one, it ensures that there's only one
switching in progress for a give inode. Second, it's used as a
mechanism to synchronize wb stat updates.
The two stats, WB_RECLAIMABLE and WB_WRITEBACK, aren't event counters
but track the current number of dirty pages and pages under writeback
respectively. As such, when an inode is moved from one wb to another,
the inode's portion of those stats have to be transferred together;
unfortunately, this is a bit tricky as those stat updates are percpu
operations which are performed without holding any lock in some
places.
This patch solves the problem in a similar way as memcg. Each such
lockless stat updates are wrapped in transaction surrounded by
unlocked_inode_to_wb_begin/end(). During normal operation, they map
to rcu_read_lock/unlock(); however, if I_WB_SWITCHING is asserted,
mapping->tree_lock is grabbed across the transaction.
In turn, the switching path sets I_WB_SWITCHING and waits for a RCU
grace period to pass before actually starting to switch, which
guarantees that all stat update paths are synchronizing against
mapping->tree_lock.
This patch still doesn't implement the actual switching.
v3: Updated on top of the recent cancel_dirty_page() updates.
unlocked_inode_to_wb_begin() now nests inside
mem_cgroup_begin_page_stat() to match the locking order.
v2: The i_wb access transaction will be used for !stat accesses too.
Function names and comments updated accordingly.
s/inode_wb_stat_unlocked_{begin|end}/unlocked_inode_to_wb_{begin|end}/
s/switch_wb/switch_wbs/
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-28 18:50:53 +00:00
|
|
|
struct mem_cgroup *memcg, struct bdi_writeback *wb);
|
2008-02-13 23:03:15 +00:00
|
|
|
int set_page_dirty(struct page *page);
|
2005-04-16 22:20:36 +00:00
|
|
|
int set_page_dirty_lock(struct page *page);
|
2015-05-22 21:13:15 +00:00
|
|
|
void cancel_dirty_page(struct page *page);
|
2005-04-16 22:20:36 +00:00
|
|
|
int clear_page_dirty_for_io(struct page *page);
|
2015-04-14 22:45:27 +00:00
|
|
|
|
2014-02-11 18:11:59 +00:00
|
|
|
int get_cmdline(struct task_struct *task, char *buffer, int buflen);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2010-08-31 13:52:27 +00:00
|
|
|
/* Is the vma a continuation of the stack vma above it? */
|
2011-05-09 11:01:09 +00:00
|
|
|
static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr)
|
2010-08-31 13:52:27 +00:00
|
|
|
{
|
|
|
|
return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
|
|
|
|
}
|
|
|
|
|
2011-05-09 11:01:09 +00:00
|
|
|
static inline int stack_guard_page_start(struct vm_area_struct *vma,
|
|
|
|
unsigned long addr)
|
|
|
|
{
|
|
|
|
return (vma->vm_flags & VM_GROWSDOWN) &&
|
|
|
|
(vma->vm_start == addr) &&
|
|
|
|
!vma_growsdown(vma->vm_prev, addr);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Is the vma a continuation of the stack vma below it? */
|
|
|
|
static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr)
|
|
|
|
{
|
|
|
|
return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int stack_guard_page_end(struct vm_area_struct *vma,
|
|
|
|
unsigned long addr)
|
|
|
|
{
|
|
|
|
return (vma->vm_flags & VM_GROWSUP) &&
|
|
|
|
(vma->vm_end == addr) &&
|
|
|
|
!vma_growsup(vma->vm_next, addr);
|
|
|
|
}
|
|
|
|
|
2014-10-09 22:25:54 +00:00
|
|
|
extern struct task_struct *task_of_stack(struct task_struct *task,
|
|
|
|
struct vm_area_struct *vma, bool in_group);
|
procfs: mark thread stack correctly in proc/<pid>/maps
Stack for a new thread is mapped by userspace code and passed via
sys_clone. This memory is currently seen as anonymous in
/proc/<pid>/maps, which makes it difficult to ascertain which mappings
are being used for thread stacks. This patch uses the individual task
stack pointers to determine which vmas are actually thread stacks.
For a multithreaded program like the following:
#include <pthread.h>
void *thread_main(void *foo)
{
while(1);
}
int main()
{
pthread_t t;
pthread_create(&t, NULL, thread_main, NULL);
pthread_join(t, NULL);
}
proc/PID/maps looks like the following:
00400000-00401000 r-xp 00000000 fd:0a 3671804 /home/siddhesh/a.out
00600000-00601000 rw-p 00000000 fd:0a 3671804 /home/siddhesh/a.out
019ef000-01a10000 rw-p 00000000 00:00 0 [heap]
7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0
7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0 [stack]
7fff627ff000-7fff62800000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
Here, one could guess that 7f8a44492000-7f8a44c92000 is a stack since
the earlier vma that has no permissions (7f8a44e3d000-7f8a4503d000) but
that is not always a reliable way to find out which vma is a thread
stack. Also, /proc/PID/maps and /proc/PID/task/TID/maps has the same
content.
With this patch in place, /proc/PID/task/TID/maps are treated as 'maps
as the task would see it' and hence, only the vma that that task uses as
stack is marked as [stack]. All other 'stack' vmas are marked as
anonymous memory. /proc/PID/maps acts as a thread group level view,
where all thread stack vmas are marked as [stack:TID] where TID is the
process ID of the task that uses that vma as stack, while the process
stack is marked as [stack].
So /proc/PID/maps will look like this:
00400000-00401000 r-xp 00000000 fd:0a 3671804 /home/siddhesh/a.out
00600000-00601000 rw-p 00000000 fd:0a 3671804 /home/siddhesh/a.out
019ef000-01a10000 rw-p 00000000 00:00 0 [heap]
7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0 [stack:1442]
7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0 [stack]
7fff627ff000-7fff62800000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
Thus marking all vmas that are used as stacks by the threads in the
thread group along with the process stack. The task level maps will
however like this:
00400000-00401000 r-xp 00000000 fd:0a 3671804 /home/siddhesh/a.out
00600000-00601000 rw-p 00000000 fd:0a 3671804 /home/siddhesh/a.out
019ef000-01a10000 rw-p 00000000 00:00 0 [heap]
7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0 [stack]
7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482 /lib64/libc-2.14.90.so
7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938 /lib64/libpthread-2.14.90.so
7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348 /lib64/ld-2.14.90.so
7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0
7fff627ff000-7fff62800000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
where only the vma that is being used as a stack by *that* task is
marked as [stack].
Analogous changes have been made to /proc/PID/smaps,
/proc/PID/numa_maps, /proc/PID/task/TID/smaps and
/proc/PID/task/TID/numa_maps. Relevant snippets from smaps and
numa_maps:
[siddhesh@localhost ~ ]$ pgrep a.out
1441
[siddhesh@localhost ~ ]$ cat /proc/1441/smaps | grep "\[stack"
7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0 [stack:1442]
7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0 [stack]
[siddhesh@localhost ~ ]$ cat /proc/1441/task/1442/smaps | grep "\[stack"
7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0 [stack]
[siddhesh@localhost ~ ]$ cat /proc/1441/task/1441/smaps | grep "\[stack"
7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0 [stack]
[siddhesh@localhost ~ ]$ cat /proc/1441/numa_maps | grep "stack"
7f8a44492000 default stack:1442 anon=2 dirty=2 N0=2
7fff6273a000 default stack anon=3 dirty=3 N0=3
[siddhesh@localhost ~ ]$ cat /proc/1441/task/1442/numa_maps | grep "stack"
7f8a44492000 default stack anon=2 dirty=2 N0=2
[siddhesh@localhost ~ ]$ cat /proc/1441/task/1441/numa_maps | grep "stack"
7fff6273a000 default stack anon=3 dirty=3 N0=3
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 23:34:04 +00:00
|
|
|
|
2007-07-19 08:48:16 +00:00
|
|
|
extern unsigned long move_page_tables(struct vm_area_struct *vma,
|
|
|
|
unsigned long old_addr, struct vm_area_struct *new_vma,
|
2012-10-08 23:31:50 +00:00
|
|
|
unsigned long new_addr, unsigned long len,
|
|
|
|
bool need_rmap_locks);
|
2012-11-19 02:14:23 +00:00
|
|
|
extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
|
|
|
|
unsigned long end, pgprot_t newprot,
|
2012-10-25 12:16:32 +00:00
|
|
|
int dirty_accountable, int prot_numa);
|
2007-07-19 08:48:16 +00:00
|
|
|
extern int mprotect_fixup(struct vm_area_struct *vma,
|
|
|
|
struct vm_area_struct **pprev, unsigned long start,
|
|
|
|
unsigned long end, unsigned long newflags);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2009-06-15 10:31:37 +00:00
|
|
|
/*
|
|
|
|
* doesn't attempt to fault and will return short.
|
|
|
|
*/
|
|
|
|
int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
|
|
|
|
struct page **pages);
|
2010-03-05 21:41:39 +00:00
|
|
|
/*
|
|
|
|
* per-process(per-mm_struct) statistics.
|
|
|
|
*/
|
|
|
|
static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
|
|
|
|
{
|
2012-03-21 23:33:49 +00:00
|
|
|
long val = atomic_long_read(&mm->rss_stat.count[member]);
|
|
|
|
|
|
|
|
#ifdef SPLIT_RSS_COUNTING
|
|
|
|
/*
|
|
|
|
* counter is updated in asynchronous manner and may go to minus.
|
|
|
|
* But it's never be expected number for users.
|
|
|
|
*/
|
|
|
|
if (val < 0)
|
|
|
|
val = 0;
|
2011-05-25 00:12:36 +00:00
|
|
|
#endif
|
2012-03-21 23:33:49 +00:00
|
|
|
return (unsigned long)val;
|
|
|
|
}
|
2010-03-05 21:41:39 +00:00
|
|
|
|
|
|
|
static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
|
|
|
|
{
|
2011-05-25 00:12:36 +00:00
|
|
|
atomic_long_add(value, &mm->rss_stat.count[member]);
|
2010-03-05 21:41:39 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void inc_mm_counter(struct mm_struct *mm, int member)
|
|
|
|
{
|
2011-05-25 00:12:36 +00:00
|
|
|
atomic_long_inc(&mm->rss_stat.count[member]);
|
2010-03-05 21:41:39 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void dec_mm_counter(struct mm_struct *mm, int member)
|
|
|
|
{
|
2011-05-25 00:12:36 +00:00
|
|
|
atomic_long_dec(&mm->rss_stat.count[member]);
|
2010-03-05 21:41:39 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long get_mm_rss(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return get_mm_counter(mm, MM_FILEPAGES) +
|
|
|
|
get_mm_counter(mm, MM_ANONPAGES);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return max(mm->hiwater_rss, get_mm_rss(mm));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return max(mm->hiwater_vm, mm->total_vm);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void update_hiwater_rss(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
unsigned long _rss = get_mm_rss(mm);
|
|
|
|
|
|
|
|
if ((mm)->hiwater_rss < _rss)
|
|
|
|
(mm)->hiwater_rss = _rss;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void update_hiwater_vm(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
if (mm->hiwater_vm < mm->total_vm)
|
|
|
|
mm->hiwater_vm = mm->total_vm;
|
|
|
|
}
|
|
|
|
|
2015-02-12 23:01:00 +00:00
|
|
|
static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
mm->hiwater_rss = get_mm_rss(mm);
|
|
|
|
}
|
|
|
|
|
2010-03-05 21:41:39 +00:00
|
|
|
static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
|
|
|
|
struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
|
|
|
|
|
|
|
|
if (*maxrss < hiwater_rss)
|
|
|
|
*maxrss = hiwater_rss;
|
|
|
|
}
|
|
|
|
|
2010-03-10 23:20:38 +00:00
|
|
|
#if defined(SPLIT_RSS_COUNTING)
|
2012-03-21 23:34:13 +00:00
|
|
|
void sync_mm_rss(struct mm_struct *mm);
|
2010-03-10 23:20:38 +00:00
|
|
|
#else
|
2012-03-21 23:34:13 +00:00
|
|
|
static inline void sync_mm_rss(struct mm_struct *mm)
|
2010-03-10 23:20:38 +00:00
|
|
|
{
|
|
|
|
}
|
|
|
|
#endif
|
2009-06-15 10:31:37 +00:00
|
|
|
|
2007-07-29 22:36:13 +00:00
|
|
|
int vma_wants_writenotify(struct vm_area_struct *vma);
|
2006-09-26 06:30:57 +00:00
|
|
|
|
2010-10-26 21:21:59 +00:00
|
|
|
extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
|
|
|
|
spinlock_t **ptl);
|
|
|
|
static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
|
|
|
|
spinlock_t **ptl)
|
|
|
|
{
|
|
|
|
pte_t *ptep;
|
|
|
|
__cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
|
|
|
|
return ptep;
|
|
|
|
}
|
2005-11-29 22:03:14 +00:00
|
|
|
|
2007-05-06 21:49:02 +00:00
|
|
|
#ifdef __PAGETABLE_PUD_FOLDED
|
|
|
|
static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
|
|
|
|
unsigned long address)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#else
|
2005-10-30 01:16:22 +00:00
|
|
|
int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
|
2007-05-06 21:49:02 +00:00
|
|
|
#endif
|
|
|
|
|
2015-02-12 22:59:59 +00:00
|
|
|
#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
|
2007-05-06 21:49:02 +00:00
|
|
|
static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
|
|
|
|
unsigned long address)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
mm: account pmd page tables to the process
Dave noticed that unprivileged process can allocate significant amount of
memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and
memory cgroup. The trick is to allocate a lot of PMD page tables. Linux
kernel doesn't account PMD tables to the process, only PTE.
The use-cases below use few tricks to allocate a lot of PMD page tables
while keeping VmRSS and VmPTE low. oom_score for the process will be 0.
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#define PUD_SIZE (1UL << 30)
#define PMD_SIZE (1UL << 21)
#define NR_PUD 130000
int main(void)
{
char *addr = NULL;
unsigned long i;
prctl(PR_SET_THP_DISABLE);
for (i = 0; i < NR_PUD ; i++) {
addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (addr == MAP_FAILED) {
perror("mmap");
break;
}
*addr = 'x';
munmap(addr, PMD_SIZE);
mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
if (addr == MAP_FAILED)
perror("re-mmap"), exit(1);
}
printf("PID %d consumed %lu KiB in PMD page tables\n",
getpid(), i * 4096 >> 10);
return pause();
}
The patch addresses the issue by account PMD tables to the process the
same way we account PTE.
The main place where PMD tables is accounted is __pmd_alloc() and
free_pmd_range(). But there're few corner cases:
- HugeTLB can share PMD page tables. The patch handles by accounting
the table to all processes who share it.
- x86 PAE pre-allocates few PMD tables on fork.
- Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity
check on exit(2).
Accounting only happens on configuration where PMD page table's level is
present (PMD is not folded). As with nr_ptes we use per-mm counter. The
counter value is used to calculate baseline for badness score by
oom-killer.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:26:50 +00:00
|
|
|
|
2015-02-12 22:59:59 +00:00
|
|
|
static inline void mm_nr_pmds_init(struct mm_struct *mm) {}
|
|
|
|
|
mm: account pmd page tables to the process
Dave noticed that unprivileged process can allocate significant amount of
memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and
memory cgroup. The trick is to allocate a lot of PMD page tables. Linux
kernel doesn't account PMD tables to the process, only PTE.
The use-cases below use few tricks to allocate a lot of PMD page tables
while keeping VmRSS and VmPTE low. oom_score for the process will be 0.
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#define PUD_SIZE (1UL << 30)
#define PMD_SIZE (1UL << 21)
#define NR_PUD 130000
int main(void)
{
char *addr = NULL;
unsigned long i;
prctl(PR_SET_THP_DISABLE);
for (i = 0; i < NR_PUD ; i++) {
addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (addr == MAP_FAILED) {
perror("mmap");
break;
}
*addr = 'x';
munmap(addr, PMD_SIZE);
mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
if (addr == MAP_FAILED)
perror("re-mmap"), exit(1);
}
printf("PID %d consumed %lu KiB in PMD page tables\n",
getpid(), i * 4096 >> 10);
return pause();
}
The patch addresses the issue by account PMD tables to the process the
same way we account PTE.
The main place where PMD tables is accounted is __pmd_alloc() and
free_pmd_range(). But there're few corner cases:
- HugeTLB can share PMD page tables. The patch handles by accounting
the table to all processes who share it.
- x86 PAE pre-allocates few PMD tables on fork.
- Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity
check on exit(2).
Accounting only happens on configuration where PMD page table's level is
present (PMD is not folded). As with nr_ptes we use per-mm counter. The
counter value is used to calculate baseline for badness score by
oom-killer.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:26:50 +00:00
|
|
|
static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
|
|
|
|
static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
|
|
|
|
|
2007-05-06 21:49:02 +00:00
|
|
|
#else
|
2005-10-30 01:16:22 +00:00
|
|
|
int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
|
mm: account pmd page tables to the process
Dave noticed that unprivileged process can allocate significant amount of
memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and
memory cgroup. The trick is to allocate a lot of PMD page tables. Linux
kernel doesn't account PMD tables to the process, only PTE.
The use-cases below use few tricks to allocate a lot of PMD page tables
while keeping VmRSS and VmPTE low. oom_score for the process will be 0.
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#define PUD_SIZE (1UL << 30)
#define PMD_SIZE (1UL << 21)
#define NR_PUD 130000
int main(void)
{
char *addr = NULL;
unsigned long i;
prctl(PR_SET_THP_DISABLE);
for (i = 0; i < NR_PUD ; i++) {
addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (addr == MAP_FAILED) {
perror("mmap");
break;
}
*addr = 'x';
munmap(addr, PMD_SIZE);
mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
if (addr == MAP_FAILED)
perror("re-mmap"), exit(1);
}
printf("PID %d consumed %lu KiB in PMD page tables\n",
getpid(), i * 4096 >> 10);
return pause();
}
The patch addresses the issue by account PMD tables to the process the
same way we account PTE.
The main place where PMD tables is accounted is __pmd_alloc() and
free_pmd_range(). But there're few corner cases:
- HugeTLB can share PMD page tables. The patch handles by accounting
the table to all processes who share it.
- x86 PAE pre-allocates few PMD tables on fork.
- Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity
check on exit(2).
Accounting only happens on configuration where PMD page table's level is
present (PMD is not folded). As with nr_ptes we use per-mm counter. The
counter value is used to calculate baseline for badness score by
oom-killer.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:26:50 +00:00
|
|
|
|
2015-02-12 22:59:59 +00:00
|
|
|
static inline void mm_nr_pmds_init(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
atomic_long_set(&mm->nr_pmds, 0);
|
|
|
|
}
|
|
|
|
|
mm: account pmd page tables to the process
Dave noticed that unprivileged process can allocate significant amount of
memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and
memory cgroup. The trick is to allocate a lot of PMD page tables. Linux
kernel doesn't account PMD tables to the process, only PTE.
The use-cases below use few tricks to allocate a lot of PMD page tables
while keeping VmRSS and VmPTE low. oom_score for the process will be 0.
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#define PUD_SIZE (1UL << 30)
#define PMD_SIZE (1UL << 21)
#define NR_PUD 130000
int main(void)
{
char *addr = NULL;
unsigned long i;
prctl(PR_SET_THP_DISABLE);
for (i = 0; i < NR_PUD ; i++) {
addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (addr == MAP_FAILED) {
perror("mmap");
break;
}
*addr = 'x';
munmap(addr, PMD_SIZE);
mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ,
MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
if (addr == MAP_FAILED)
perror("re-mmap"), exit(1);
}
printf("PID %d consumed %lu KiB in PMD page tables\n",
getpid(), i * 4096 >> 10);
return pause();
}
The patch addresses the issue by account PMD tables to the process the
same way we account PTE.
The main place where PMD tables is accounted is __pmd_alloc() and
free_pmd_range(). But there're few corner cases:
- HugeTLB can share PMD page tables. The patch handles by accounting
the table to all processes who share it.
- x86 PAE pre-allocates few PMD tables on fork.
- Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity
check on exit(2).
Accounting only happens on configuration where PMD page table's level is
present (PMD is not folded). As with nr_ptes we use per-mm counter. The
counter value is used to calculate baseline for badness score by
oom-killer.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 23:26:50 +00:00
|
|
|
static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return atomic_long_read(&mm->nr_pmds);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void mm_inc_nr_pmds(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
atomic_long_inc(&mm->nr_pmds);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void mm_dec_nr_pmds(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
atomic_long_dec(&mm->nr_pmds);
|
|
|
|
}
|
2007-05-06 21:49:02 +00:00
|
|
|
#endif
|
|
|
|
|
2011-01-13 23:46:43 +00:00
|
|
|
int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
|
|
|
|
pmd_t *pmd, unsigned long address);
|
2005-10-30 01:16:22 +00:00
|
|
|
int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
* The following ifdef needed to get the 4level-fixup.h header to work.
|
|
|
|
* Remove it when 4level-fixup.h has been removed.
|
|
|
|
*/
|
2005-10-30 01:16:22 +00:00
|
|
|
#if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK)
|
2005-04-16 22:20:36 +00:00
|
|
|
static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
|
|
|
|
{
|
2005-10-30 01:16:22 +00:00
|
|
|
return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))?
|
|
|
|
NULL: pud_offset(pgd, address);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
|
|
|
|
{
|
2005-10-30 01:16:22 +00:00
|
|
|
return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
|
|
|
|
NULL: pmd_offset(pud, address);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
2005-10-30 01:16:22 +00:00
|
|
|
#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */
|
|
|
|
|
2013-11-14 22:30:45 +00:00
|
|
|
#if USE_SPLIT_PTE_PTLOCKS
|
2013-12-20 11:35:58 +00:00
|
|
|
#if ALLOC_SPLIT_PTLOCKS
|
2014-01-21 23:49:07 +00:00
|
|
|
void __init ptlock_cache_init(void);
|
2013-11-14 22:31:52 +00:00
|
|
|
extern bool ptlock_alloc(struct page *page);
|
|
|
|
extern void ptlock_free(struct page *page);
|
|
|
|
|
|
|
|
static inline spinlock_t *ptlock_ptr(struct page *page)
|
|
|
|
{
|
|
|
|
return page->ptl;
|
|
|
|
}
|
2013-12-20 11:35:58 +00:00
|
|
|
#else /* ALLOC_SPLIT_PTLOCKS */
|
2014-01-21 23:49:07 +00:00
|
|
|
static inline void ptlock_cache_init(void)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
2013-11-14 22:31:51 +00:00
|
|
|
static inline bool ptlock_alloc(struct page *page)
|
|
|
|
{
|
|
|
|
return true;
|
|
|
|
}
|
2013-11-14 22:31:52 +00:00
|
|
|
|
2013-11-14 22:31:51 +00:00
|
|
|
static inline void ptlock_free(struct page *page)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline spinlock_t *ptlock_ptr(struct page *page)
|
|
|
|
{
|
2013-11-14 22:31:52 +00:00
|
|
|
return &page->ptl;
|
2013-11-14 22:31:51 +00:00
|
|
|
}
|
2013-12-20 11:35:58 +00:00
|
|
|
#endif /* ALLOC_SPLIT_PTLOCKS */
|
2013-11-14 22:31:51 +00:00
|
|
|
|
|
|
|
static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
|
|
|
|
{
|
|
|
|
return ptlock_ptr(pmd_page(*pmd));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline bool ptlock_init(struct page *page)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* prep_new_page() initialize page->private (and therefore page->ptl)
|
|
|
|
* with 0. Make sure nobody took it in use in between.
|
|
|
|
*
|
|
|
|
* It can happen if arch try to use slab for page table allocation:
|
|
|
|
* slab code uses page->slab_cache and page->first_page (for tail
|
|
|
|
* pages), which share storage with page->ptl.
|
|
|
|
*/
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
|
2013-11-14 22:31:51 +00:00
|
|
|
if (!ptlock_alloc(page))
|
|
|
|
return false;
|
|
|
|
spin_lock_init(ptlock_ptr(page));
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Reset page->mapping so free_pages_check won't complain. */
|
|
|
|
static inline void pte_lock_deinit(struct page *page)
|
|
|
|
{
|
|
|
|
page->mapping = NULL;
|
|
|
|
ptlock_free(page);
|
|
|
|
}
|
|
|
|
|
2013-11-14 22:30:45 +00:00
|
|
|
#else /* !USE_SPLIT_PTE_PTLOCKS */
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
/*
|
|
|
|
* We use mm->page_table_lock to guard all pagetable pages of the mm.
|
|
|
|
*/
|
2013-11-14 22:31:51 +00:00
|
|
|
static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
|
|
|
|
{
|
|
|
|
return &mm->page_table_lock;
|
|
|
|
}
|
2014-01-21 23:49:07 +00:00
|
|
|
static inline void ptlock_cache_init(void) {}
|
2013-11-14 22:31:51 +00:00
|
|
|
static inline bool ptlock_init(struct page *page) { return true; }
|
|
|
|
static inline void pte_lock_deinit(struct page *page) {}
|
2013-11-14 22:30:45 +00:00
|
|
|
#endif /* USE_SPLIT_PTE_PTLOCKS */
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
|
2014-01-21 23:49:07 +00:00
|
|
|
static inline void pgtable_init(void)
|
|
|
|
{
|
|
|
|
ptlock_cache_init();
|
|
|
|
pgtable_cache_init();
|
|
|
|
}
|
|
|
|
|
2013-11-14 22:31:20 +00:00
|
|
|
static inline bool pgtable_page_ctor(struct page *page)
|
2008-02-08 12:22:04 +00:00
|
|
|
{
|
|
|
|
inc_zone_page_state(page, NR_PAGETABLE);
|
2013-11-14 22:31:51 +00:00
|
|
|
return ptlock_init(page);
|
2008-02-08 12:22:04 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void pgtable_page_dtor(struct page *page)
|
|
|
|
{
|
|
|
|
pte_lock_deinit(page);
|
|
|
|
dec_zone_page_state(page, NR_PAGETABLE);
|
|
|
|
}
|
|
|
|
|
2005-10-30 01:16:23 +00:00
|
|
|
#define pte_offset_map_lock(mm, pmd, address, ptlp) \
|
|
|
|
({ \
|
[PATCH] mm: split page table lock
Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.
This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock. (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)
In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.
Splitting the lock is not quite for free: another cacheline access. Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS. But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.
There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:40 +00:00
|
|
|
spinlock_t *__ptl = pte_lockptr(mm, pmd); \
|
2005-10-30 01:16:23 +00:00
|
|
|
pte_t *__pte = pte_offset_map(pmd, address); \
|
|
|
|
*(ptlp) = __ptl; \
|
|
|
|
spin_lock(__ptl); \
|
|
|
|
__pte; \
|
|
|
|
})
|
|
|
|
|
|
|
|
#define pte_unmap_unlock(pte, ptl) do { \
|
|
|
|
spin_unlock(ptl); \
|
|
|
|
pte_unmap(pte); \
|
|
|
|
} while (0)
|
|
|
|
|
2011-01-13 23:46:43 +00:00
|
|
|
#define pte_alloc_map(mm, vma, pmd, address) \
|
|
|
|
((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \
|
|
|
|
pmd, address))? \
|
|
|
|
NULL: pte_offset_map(pmd, address))
|
2005-10-30 01:16:22 +00:00
|
|
|
|
2005-10-30 01:16:23 +00:00
|
|
|
#define pte_alloc_map_lock(mm, pmd, address, ptlp) \
|
2011-01-13 23:46:43 +00:00
|
|
|
((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \
|
|
|
|
pmd, address))? \
|
2005-10-30 01:16:23 +00:00
|
|
|
NULL: pte_offset_map_lock(mm, pmd, address, ptlp))
|
|
|
|
|
2005-10-30 01:16:22 +00:00
|
|
|
#define pte_alloc_kernel(pmd, address) \
|
2011-01-13 23:46:43 +00:00
|
|
|
((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
|
2005-10-30 01:16:22 +00:00
|
|
|
NULL: pte_offset_kernel(pmd, address))
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2013-11-14 22:31:07 +00:00
|
|
|
#if USE_SPLIT_PMD_PTLOCKS
|
|
|
|
|
2014-02-13 12:53:33 +00:00
|
|
|
static struct page *pmd_to_page(pmd_t *pmd)
|
|
|
|
{
|
|
|
|
unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
|
|
|
|
return virt_to_page((void *)((unsigned long) pmd & mask));
|
|
|
|
}
|
|
|
|
|
2013-11-14 22:31:07 +00:00
|
|
|
static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
|
|
|
|
{
|
2014-02-13 12:53:33 +00:00
|
|
|
return ptlock_ptr(pmd_to_page(pmd));
|
2013-11-14 22:31:07 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline bool pgtable_pmd_page_ctor(struct page *page)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
|
|
page->pmd_huge_pte = NULL;
|
|
|
|
#endif
|
2013-11-14 22:31:51 +00:00
|
|
|
return ptlock_init(page);
|
2013-11-14 22:31:07 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void pgtable_pmd_page_dtor(struct page *page)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
2014-01-23 23:52:54 +00:00
|
|
|
VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
|
2013-11-14 22:31:07 +00:00
|
|
|
#endif
|
2013-11-14 22:31:51 +00:00
|
|
|
ptlock_free(page);
|
2013-11-14 22:31:07 +00:00
|
|
|
}
|
|
|
|
|
2014-02-13 12:53:33 +00:00
|
|
|
#define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte)
|
2013-11-14 22:31:07 +00:00
|
|
|
|
|
|
|
#else
|
|
|
|
|
2013-11-14 22:30:51 +00:00
|
|
|
static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
|
|
|
|
{
|
|
|
|
return &mm->page_table_lock;
|
|
|
|
}
|
|
|
|
|
2013-11-14 22:31:07 +00:00
|
|
|
static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; }
|
|
|
|
static inline void pgtable_pmd_page_dtor(struct page *page) {}
|
|
|
|
|
2013-11-14 22:30:59 +00:00
|
|
|
#define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
|
2013-11-14 22:30:51 +00:00
|
|
|
|
2013-11-14 22:31:07 +00:00
|
|
|
#endif
|
|
|
|
|
2013-11-14 22:30:51 +00:00
|
|
|
static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
|
|
|
|
{
|
|
|
|
spinlock_t *ptl = pmd_lockptr(mm, pmd);
|
|
|
|
spin_lock(ptl);
|
|
|
|
return ptl;
|
|
|
|
}
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
extern void free_area_init(unsigned long * zones_size);
|
2008-07-24 04:27:20 +00:00
|
|
|
extern void free_area_init_node(int nid, unsigned long * zones_size,
|
|
|
|
unsigned long zone_start_pfn, unsigned long *zholes_size);
|
2012-03-28 17:30:03 +00:00
|
|
|
extern void free_initmem(void);
|
|
|
|
|
2013-04-29 22:06:21 +00:00
|
|
|
/*
|
|
|
|
* Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
|
|
|
|
* into the buddy system. The freed pages will be poisoned with pattern
|
2013-07-03 22:02:51 +00:00
|
|
|
* "poison" if it's within range [0, UCHAR_MAX].
|
2013-04-29 22:06:21 +00:00
|
|
|
* Return pages freed into the buddy system.
|
|
|
|
*/
|
mm: change signature of free_reserved_area() to fix building warnings
Change signature of free_reserved_area() according to Russell King's
suggestion to fix following build warnings:
arch/arm/mm/init.c: In function 'mem_init':
arch/arm/mm/init.c:603:2: warning: passing argument 1 of 'free_reserved_area' makes integer from pointer without a cast [enabled by default]
free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL);
^
In file included from include/linux/mman.h:4:0,
from arch/arm/mm/init.c:15:
include/linux/mm.h:1301:22: note: expected 'long unsigned int' but argument is of type 'void *'
extern unsigned long free_reserved_area(unsigned long start, unsigned long end,
mm/page_alloc.c: In function 'free_reserved_area':
>> mm/page_alloc.c:5134:3: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default]
In file included from arch/mips/include/asm/page.h:49:0,
from include/linux/mmzone.h:20,
from include/linux/gfp.h:4,
from include/linux/mm.h:8,
from mm/page_alloc.c:18:
arch/mips/include/asm/io.h:119:29: note: expected 'const volatile void *' but argument is of type 'long unsigned int'
mm/page_alloc.c: In function 'free_area_init_nodes':
mm/page_alloc.c:5030:34: warning: array subscript is below array bounds [-Warray-bounds]
Also address some minor code review comments.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: <sworddragon2@aol.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:02:48 +00:00
|
|
|
extern unsigned long free_reserved_area(void *start, void *end,
|
2013-04-29 22:06:21 +00:00
|
|
|
int poison, char *s);
|
2013-07-03 22:03:14 +00:00
|
|
|
|
2013-04-29 22:07:00 +00:00
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
|
|
/*
|
|
|
|
* Free a highmem page into the buddy system, adjusting totalhigh_pages
|
|
|
|
* and totalram_pages.
|
|
|
|
*/
|
|
|
|
extern void free_highmem_page(struct page *page);
|
|
|
|
#endif
|
2013-04-29 22:06:21 +00:00
|
|
|
|
2013-07-03 22:03:14 +00:00
|
|
|
extern void adjust_managed_page_count(struct page *page, long count);
|
2013-07-03 22:03:41 +00:00
|
|
|
extern void mem_init_print_info(const char *str);
|
2013-04-29 22:06:21 +00:00
|
|
|
|
2015-06-30 21:56:48 +00:00
|
|
|
extern void reserve_bootmem_region(unsigned long start, unsigned long end);
|
|
|
|
|
2013-04-29 22:06:21 +00:00
|
|
|
/* Free the reserved page into the buddy system, so it gets managed. */
|
|
|
|
static inline void __free_reserved_page(struct page *page)
|
|
|
|
{
|
|
|
|
ClearPageReserved(page);
|
|
|
|
init_page_count(page);
|
|
|
|
__free_page(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void free_reserved_page(struct page *page)
|
|
|
|
{
|
|
|
|
__free_reserved_page(page);
|
|
|
|
adjust_managed_page_count(page, 1);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void mark_page_reserved(struct page *page)
|
|
|
|
{
|
|
|
|
SetPageReserved(page);
|
|
|
|
adjust_managed_page_count(page, -1);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Default method to free all the __init memory into the buddy system.
|
2013-07-03 22:02:51 +00:00
|
|
|
* The freed pages will be poisoned with pattern "poison" if it's within
|
|
|
|
* range [0, UCHAR_MAX].
|
|
|
|
* Return pages freed into the buddy system.
|
2013-04-29 22:06:21 +00:00
|
|
|
*/
|
|
|
|
static inline unsigned long free_initmem_default(int poison)
|
|
|
|
{
|
|
|
|
extern char __init_begin[], __init_end[];
|
|
|
|
|
mm: change signature of free_reserved_area() to fix building warnings
Change signature of free_reserved_area() according to Russell King's
suggestion to fix following build warnings:
arch/arm/mm/init.c: In function 'mem_init':
arch/arm/mm/init.c:603:2: warning: passing argument 1 of 'free_reserved_area' makes integer from pointer without a cast [enabled by default]
free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL);
^
In file included from include/linux/mman.h:4:0,
from arch/arm/mm/init.c:15:
include/linux/mm.h:1301:22: note: expected 'long unsigned int' but argument is of type 'void *'
extern unsigned long free_reserved_area(unsigned long start, unsigned long end,
mm/page_alloc.c: In function 'free_reserved_area':
>> mm/page_alloc.c:5134:3: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default]
In file included from arch/mips/include/asm/page.h:49:0,
from include/linux/mmzone.h:20,
from include/linux/gfp.h:4,
from include/linux/mm.h:8,
from mm/page_alloc.c:18:
arch/mips/include/asm/io.h:119:29: note: expected 'const volatile void *' but argument is of type 'long unsigned int'
mm/page_alloc.c: In function 'free_area_init_nodes':
mm/page_alloc.c:5030:34: warning: array subscript is below array bounds [-Warray-bounds]
Also address some minor code review comments.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: <sworddragon2@aol.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 22:02:48 +00:00
|
|
|
return free_reserved_area(&__init_begin, &__init_end,
|
2013-04-29 22:06:21 +00:00
|
|
|
poison, "unused kernel");
|
|
|
|
}
|
|
|
|
|
2013-07-03 22:03:41 +00:00
|
|
|
static inline unsigned long get_num_physpages(void)
|
|
|
|
{
|
|
|
|
int nid;
|
|
|
|
unsigned long phys_pages = 0;
|
|
|
|
|
|
|
|
for_each_online_node(nid)
|
|
|
|
phys_pages += node_present_pages(nid);
|
|
|
|
|
|
|
|
return phys_pages;
|
|
|
|
}
|
|
|
|
|
2011-12-08 18:22:09 +00:00
|
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
/*
|
2011-12-08 18:22:09 +00:00
|
|
|
* With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
* zones, allocate the backing mem_map and account for memory holes in a more
|
|
|
|
* architecture independent manner. This is a substitute for creating the
|
|
|
|
* zone_sizes[] and zholes_size[] arrays and passing them to
|
|
|
|
* free_area_init_node()
|
|
|
|
*
|
|
|
|
* An architecture is expected to register range of page frames backed by
|
2011-12-08 18:22:09 +00:00
|
|
|
* physical memory with memblock_add[_node]() before calling
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
* free_area_init_nodes() passing in the PFN each zone ends at. At a basic
|
|
|
|
* usage, an architecture is expected to do something like
|
|
|
|
*
|
|
|
|
* unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
|
|
|
|
* max_highmem_pfn};
|
|
|
|
* for_each_valid_physical_page_range()
|
2011-12-08 18:22:09 +00:00
|
|
|
* memblock_add_node(base, size, nid)
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
* free_area_init_nodes(max_zone_pfns);
|
|
|
|
*
|
2011-12-08 18:22:09 +00:00
|
|
|
* free_bootmem_with_active_regions() calls free_bootmem_node() for each
|
|
|
|
* registered physical page range. Similarly
|
|
|
|
* sparse_memory_present_with_active_regions() calls memory_present() for
|
|
|
|
* each range when SPARSEMEM is enabled.
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
*
|
|
|
|
* See mm/page_alloc.c for more information on each function exposed by
|
2011-12-08 18:22:09 +00:00
|
|
|
* CONFIG_HAVE_MEMBLOCK_NODE_MAP.
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
*/
|
|
|
|
extern void free_area_init_nodes(unsigned long *max_zone_pfn);
|
x86, numa: Implement pfn -> nid mapping granularity check
SPARSEMEM w/o VMEMMAP and DISCONTIGMEM, both used only on 32bit, use
sections array to map pfn to nid which is limited in granularity. If
NUMA nodes are laid out such that the mapping cannot be accurate, boot
will fail triggering BUG_ON() in mminit_verify_page_links().
On 32bit, it's 512MiB w/ PAE and SPARSEMEM. This seems to have been
granular enough until commit 2706a0bf7b (x86, NUMA: Enable
CONFIG_AMD_NUMA on 32bit too). Apparently, there is a machine which
aligns NUMA nodes to 128MiB and has only AMD NUMA but not SRAT. This
led to the following BUG_ON().
On node 0 totalpages: 2096615
DMA zone: 32 pages used for memmap
DMA zone: 0 pages reserved
DMA zone: 3927 pages, LIFO batch:0
Normal zone: 1740 pages used for memmap
Normal zone: 220978 pages, LIFO batch:31
HighMem zone: 16405 pages used for memmap
HighMem zone: 1853533 pages, LIFO batch:31
BUG: Int 6: CR2 (null)
EDI (null) ESI 00000002 EBP 00000002 ESP c1543ecc
EBX f2400000 EDX 00000006 ECX (null) EAX 00000001
err (null) EIP c16209aa CS 00000060 flg 00010002
Stack: f2400000 00220000 f7200800 c1620613 00220000 01000000 04400000 00238000
(null) f7200000 00000002 f7200b58 f7200800 c1620929 000375fe (null)
f7200b80 c16395f0 00200a02 f7200a80 (null) 000375fe 00000002 (null)
Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00181-g2706a0b #17
Call Trace:
[<c136b1e5>] ? early_fault+0x2e/0x2e
[<c16209aa>] ? mminit_verify_page_links+0x12/0x42
[<c1620613>] ? memmap_init_zone+0xaf/0x10c
[<c1620929>] ? free_area_init_node+0x2b9/0x2e3
[<c1607e99>] ? free_area_init_nodes+0x3f2/0x451
[<c1601d80>] ? paging_init+0x112/0x118
[<c15f578d>] ? setup_arch+0x791/0x82f
[<c15f43d9>] ? start_kernel+0x6a/0x257
This patch implements node_map_pfn_alignment() which determines
maximum internode alignment and update numa_register_memblks() to
reject NUMA configuration if alignment exceeds the pfn -> nid mapping
granularity of the memory model as determined by PAGES_PER_SECTION.
This makes the problematic machine boot w/ flatmem by rejecting the
NUMA config and provides protection against crazy NUMA configurations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074534.GB2872@htj.dyndns.org
LKML-Reference: <20110628174613.GP478@escobedo.osrc.amd.com>
Reported-and-Tested-by: Hans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-12 07:45:34 +00:00
|
|
|
unsigned long node_map_pfn_alignment(void);
|
x86: Fix checking of SRAT when node 0 ram is not from 0
Found one system that boot from socket1 instead of socket0, SRAT get rejected...
[ 0.000000] SRAT: Node 1 PXM 0 0-a0000
[ 0.000000] SRAT: Node 1 PXM 0 100000-80000000
[ 0.000000] SRAT: Node 1 PXM 0 100000000-2080000000
[ 0.000000] SRAT: Node 0 PXM 1 2080000000-4080000000
[ 0.000000] SRAT: Node 2 PXM 2 4080000000-6080000000
[ 0.000000] SRAT: Node 3 PXM 3 6080000000-8080000000
[ 0.000000] SRAT: Node 4 PXM 4 8080000000-a080000000
[ 0.000000] SRAT: Node 5 PXM 5 a080000000-c080000000
[ 0.000000] SRAT: Node 6 PXM 6 c080000000-e080000000
[ 0.000000] SRAT: Node 7 PXM 7 e080000000-10080000000
...
[ 0.000000] NUMA: Allocated memnodemap from 500000 - 701040
[ 0.000000] NUMA: Using 20 for the hash shift.
[ 0.000000] Adding active range (0, 0x2080000, 0x4080000) 0 entries of 3200 used
[ 0.000000] Adding active range (1, 0x0, 0x96) 1 entries of 3200 used
[ 0.000000] Adding active range (1, 0x100, 0x7f750) 2 entries of 3200 used
[ 0.000000] Adding active range (1, 0x100000, 0x2080000) 3 entries of 3200 used
[ 0.000000] Adding active range (2, 0x4080000, 0x6080000) 4 entries of 3200 used
[ 0.000000] Adding active range (3, 0x6080000, 0x8080000) 5 entries of 3200 used
[ 0.000000] Adding active range (4, 0x8080000, 0xa080000) 6 entries of 3200 used
[ 0.000000] Adding active range (5, 0xa080000, 0xc080000) 7 entries of 3200 used
[ 0.000000] Adding active range (6, 0xc080000, 0xe080000) 8 entries of 3200 used
[ 0.000000] Adding active range (7, 0xe080000, 0x10080000) 9 entries of 3200 used
[ 0.000000] SRAT: PXMs only cover 917504MB of your 1048566MB e820 RAM. Not used.
[ 0.000000] SRAT: SRAT not used.
the early_node_map is not sorted because node0 with non zero start come first.
so try to sort it right away after all regions are registered.
also fixs refression by 8716273c (x86: Export srat physical topology)
-v2: make it more solid to handle cross node case like node0 [0,4g), [8,12g) and node1 [4g, 8g), [12g, 16g)
-v3: update comments.
Reported-and-tested-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B2579D2.3010201@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-16 01:59:02 +00:00
|
|
|
unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
|
|
|
|
unsigned long end_pfn);
|
[PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.
The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.
Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightly
Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.
There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.
The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.
Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixes
This patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:49:43 +00:00
|
|
|
extern unsigned long absent_pages_in_range(unsigned long start_pfn,
|
|
|
|
unsigned long end_pfn);
|
|
|
|
extern void get_pfn_range_for_nid(unsigned int nid,
|
|
|
|
unsigned long *start_pfn, unsigned long *end_pfn);
|
|
|
|
extern unsigned long find_min_pfn_with_active_regions(void);
|
|
|
|
extern void free_bootmem_with_active_regions(int nid,
|
|
|
|
unsigned long max_low_pfn);
|
|
|
|
extern void sparse_memory_present_with_active_regions(int nid);
|
mm: clean up for early_pfn_to_nid()
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 22:48:32 +00:00
|
|
|
|
2011-12-08 18:22:09 +00:00
|
|
|
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
|
mm: clean up for early_pfn_to_nid()
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 22:48:32 +00:00
|
|
|
|
2011-12-08 18:22:09 +00:00
|
|
|
#if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \
|
mm: clean up for early_pfn_to_nid()
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 22:48:32 +00:00
|
|
|
!defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID)
|
2015-06-30 21:56:55 +00:00
|
|
|
static inline int __early_pfn_to_nid(unsigned long pfn,
|
|
|
|
struct mminit_pfnnid_cache *state)
|
mm: clean up for early_pfn_to_nid()
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 22:48:32 +00:00
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
/* please see mm/page_alloc.c */
|
|
|
|
extern int __meminit early_pfn_to_nid(unsigned long pfn);
|
|
|
|
/* there is a per-arch backend function. */
|
2015-06-30 21:56:55 +00:00
|
|
|
extern int __meminit __early_pfn_to_nid(unsigned long pfn,
|
|
|
|
struct mminit_pfnnid_cache *state);
|
mm: clean up for early_pfn_to_nid()
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 22:48:32 +00:00
|
|
|
#endif
|
|
|
|
|
2006-09-27 08:49:56 +00:00
|
|
|
extern void set_dma_reserve(unsigned long new_dma_reserve);
|
2007-01-11 07:15:30 +00:00
|
|
|
extern void memmap_init_zone(unsigned long, int, unsigned long,
|
|
|
|
unsigned long, enum memmap_context);
|
2009-06-16 22:32:48 +00:00
|
|
|
extern void setup_per_zone_wmarks(void);
|
2011-05-25 00:11:32 +00:00
|
|
|
extern int __meminit init_per_zone_wmark_min(void);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern void mem_init(void);
|
2009-01-08 12:04:47 +00:00
|
|
|
extern void __init mmap_init(void);
|
2011-03-24 22:18:15 +00:00
|
|
|
extern void show_mem(unsigned int flags);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern void si_meminfo(struct sysinfo * val);
|
|
|
|
extern void si_meminfo_node(struct sysinfo *val, int nid);
|
|
|
|
|
2011-11-01 00:08:35 +00:00
|
|
|
extern __printf(3, 4)
|
|
|
|
void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);
|
2011-05-25 00:12:16 +00:00
|
|
|
|
2005-06-22 00:14:47 +00:00
|
|
|
extern void setup_per_cpu_pageset(void);
|
|
|
|
|
2009-09-22 00:01:16 +00:00
|
|
|
extern void zone_pcp_update(struct zone *zone);
|
2012-07-31 23:43:32 +00:00
|
|
|
extern void zone_pcp_reset(struct zone *zone);
|
2009-09-22 00:01:16 +00:00
|
|
|
|
2013-02-23 00:34:42 +00:00
|
|
|
/* page_alloc.c */
|
|
|
|
extern int min_free_kbytes;
|
|
|
|
|
2009-01-08 12:04:47 +00:00
|
|
|
/* nommu.c */
|
2009-04-02 23:56:32 +00:00
|
|
|
extern atomic_long_t mmap_pages_allocated;
|
nommu: fix shared mmap after truncate shrinkage problems
Fix a problem in NOMMU mmap with ramfs whereby a shared mmap can happen
over the end of a truncation. The problem is that
ramfs_nommu_check_mappings() checks that the reduced file size against the
VMA tree, but not the vm_region tree.
The following sequence of events can cause the problem:
fd = open("/tmp/x", O_RDWR|O_TRUNC|O_CREAT, 0600);
ftruncate(fd, 32 * 1024);
a = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
b = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
munmap(a, 32 * 1024);
ftruncate(fd, 16 * 1024);
c = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
Mapping 'a' creates a vm_region covering 32KB of the file. Mapping 'b'
sees that the vm_region from 'a' is covering the region it wants and so
shares it, pinning it in memory.
Mapping 'a' then goes away and the file is truncated to the end of VMA
'b'. However, the region allocated by 'a' is still in effect, and has
_not_ been reduced.
Mapping 'c' is then created, and because there's a vm_region covering the
desired region, get_unmapped_area() is _not_ called to repeat the check,
and the mapping is granted, even though the pages from the latter half of
the mapping have been discarded.
However:
d = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
Mapping 'd' should work, and should end up sharing the region allocated by
'a'.
To deal with this, we shrink the vm_region struct during the truncation,
lest do_mmap_pgoff() take it as licence to share the full region
automatically without calling the get_unmapped_area() file op again.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-16 01:01:39 +00:00
|
|
|
extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
|
2009-01-08 12:04:47 +00:00
|
|
|
|
2012-10-08 23:31:25 +00:00
|
|
|
/* interval_tree.c */
|
|
|
|
void vma_interval_tree_insert(struct vm_area_struct *node,
|
|
|
|
struct rb_root *root);
|
2012-10-08 23:31:35 +00:00
|
|
|
void vma_interval_tree_insert_after(struct vm_area_struct *node,
|
|
|
|
struct vm_area_struct *prev,
|
|
|
|
struct rb_root *root);
|
2012-10-08 23:31:25 +00:00
|
|
|
void vma_interval_tree_remove(struct vm_area_struct *node,
|
|
|
|
struct rb_root *root);
|
|
|
|
struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root,
|
|
|
|
unsigned long start, unsigned long last);
|
|
|
|
struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
|
|
|
|
unsigned long start, unsigned long last);
|
|
|
|
|
|
|
|
#define vma_interval_tree_foreach(vma, root, start, last) \
|
|
|
|
for (vma = vma_interval_tree_iter_first(root, start, last); \
|
|
|
|
vma; vma = vma_interval_tree_iter_next(vma, start, last))
|
2005-04-16 22:20:36 +00:00
|
|
|
|
mm anon rmap: replace same_anon_vma linked list with an interval tree.
When a large VMA (anon or private file mapping) is first touched, which
will populate its anon_vma field, and then split into many regions through
the use of mprotect(), the original anon_vma ends up linking all of the
vmas on a linked list. This can cause rmap to become inefficient, as we
have to walk potentially thousands of irrelevent vmas before finding the
one a given anon page might fall into.
By replacing the same_anon_vma linked list with an interval tree (where
each avc's interval is determined by its vma's start and last pgoffs), we
can make rmap efficient for this use case again.
While the change is large, all of its pieces are fairly simple.
Most places that were walking the same_anon_vma list were looking for a
known pgoff, so they can just use the anon_vma_interval_tree_foreach()
interval tree iterator instead. The exception here is ksm, where the
page's index is not known. It would probably be possible to rework ksm so
that the index would be known, but for now I have decided to keep things
simple and just walk the entirety of the interval tree there.
When updating vma's that already have an anon_vma assigned, we must take
care to re-index the corresponding avc's on their interval tree. This is
done through the use of anon_vma_interval_tree_pre_update_vma() and
anon_vma_interval_tree_post_update_vma(), which remove the avc's from
their interval tree before the update and re-insert them after the update.
The anon_vma stays locked during the update, so there is no chance that
rmap would miss the vmas that are being updated.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08 23:31:39 +00:00
|
|
|
void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
|
|
|
|
struct rb_root *root);
|
|
|
|
void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
|
|
|
|
struct rb_root *root);
|
|
|
|
struct anon_vma_chain *anon_vma_interval_tree_iter_first(
|
|
|
|
struct rb_root *root, unsigned long start, unsigned long last);
|
|
|
|
struct anon_vma_chain *anon_vma_interval_tree_iter_next(
|
|
|
|
struct anon_vma_chain *node, unsigned long start, unsigned long last);
|
2012-10-08 23:31:45 +00:00
|
|
|
#ifdef CONFIG_DEBUG_VM_RB
|
|
|
|
void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
|
|
|
|
#endif
|
mm anon rmap: replace same_anon_vma linked list with an interval tree.
When a large VMA (anon or private file mapping) is first touched, which
will populate its anon_vma field, and then split into many regions through
the use of mprotect(), the original anon_vma ends up linking all of the
vmas on a linked list. This can cause rmap to become inefficient, as we
have to walk potentially thousands of irrelevent vmas before finding the
one a given anon page might fall into.
By replacing the same_anon_vma linked list with an interval tree (where
each avc's interval is determined by its vma's start and last pgoffs), we
can make rmap efficient for this use case again.
While the change is large, all of its pieces are fairly simple.
Most places that were walking the same_anon_vma list were looking for a
known pgoff, so they can just use the anon_vma_interval_tree_foreach()
interval tree iterator instead. The exception here is ksm, where the
page's index is not known. It would probably be possible to rework ksm so
that the index would be known, but for now I have decided to keep things
simple and just walk the entirety of the interval tree there.
When updating vma's that already have an anon_vma assigned, we must take
care to re-index the corresponding avc's on their interval tree. This is
done through the use of anon_vma_interval_tree_pre_update_vma() and
anon_vma_interval_tree_post_update_vma(), which remove the avc's from
their interval tree before the update and re-insert them after the update.
The anon_vma stays locked during the update, so there is no chance that
rmap would miss the vmas that are being updated.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08 23:31:39 +00:00
|
|
|
|
|
|
|
#define anon_vma_interval_tree_foreach(avc, root, start, last) \
|
|
|
|
for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
|
|
|
|
avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/* mmap.c */
|
2007-08-22 21:01:28 +00:00
|
|
|
extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
|
mm: change anon_vma linking to fix multi-process server scalability issue
The old anon_vma code can lead to scalability issues with heavily forking
workloads. Specifically, each anon_vma will be shared between the parent
process and all its child processes.
In a workload with 1000 child processes and a VMA with 1000 anonymous
pages per process that get COWed, this leads to a system with a million
anonymous pages in the same anon_vma, each of which is mapped in just one
of the 1000 processes. However, the current rmap code needs to walk them
all, leading to O(N) scanning complexity for each page.
This can result in systems where one CPU is walking the page tables of
1000 processes in page_referenced_one, while all other CPUs are stuck on
the anon_vma lock. This leads to catastrophic failure for a benchmark
like AIM7, where the total number of processes can reach in the tens of
thousands. Real workloads are still a factor 10 less process intensive
than AIM7, but they are catching up.
This patch changes the way anon_vmas and VMAs are linked, which allows us
to associate multiple anon_vmas with a VMA. At fork time, each child
process gets its own anon_vmas, in which its COWed pages will be
instantiated. The parents' anon_vma is also linked to the VMA, because
non-COWed pages could be present in any of the children.
This reduces rmap scanning complexity to O(1) for the pages of the 1000
child processes, with O(N) complexity for at most 1/N pages in the system.
This reduces the average scanning cost in heavily forking workloads from
O(N) to 2.
The only real complexity in this patch stems from the fact that linking a
VMA to anon_vmas now involves memory allocations. This means vma_adjust
can fail, if it needs to attach a VMA to anon_vma structures. This in
turn means error handling needs to be added to the calling functions.
A second source of complexity is that, because there can be multiple
anon_vmas, the anon_vma linking in vma_adjust can no longer be done under
"the" anon_vma lock. To prevent the rmap code from walking up an
incomplete VMA, this patch introduces the VM_LOCK_RMAP VMA flag. This bit
flag uses the same slot as the NOMMU VM_MAPPED_COPY, with an ifdef in mm.h
to make sure it is impossible to compile a kernel that needs both symbolic
values for the same bitflag.
Some test results:
Without the anon_vma changes, when AIM7 hits around 9.7k users (on a test
box with 16GB RAM and not quite enough IO), the system ends up running
>99% in system time, with every CPU on the same anon_vma lock in the
pageout code.
With these changes, AIM7 hits the cross-over point around 29.7k users.
This happens with ~99% IO wait time, there never seems to be any spike in
system time. The anon_vma lock contention appears to be resolved.
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-05 21:42:07 +00:00
|
|
|
extern int vma_adjust(struct vm_area_struct *vma, unsigned long start,
|
2005-04-16 22:20:36 +00:00
|
|
|
unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert);
|
|
|
|
extern struct vm_area_struct *vma_merge(struct mm_struct *,
|
|
|
|
struct vm_area_struct *prev, unsigned long addr, unsigned long end,
|
|
|
|
unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
|
|
|
|
struct mempolicy *);
|
|
|
|
extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
|
|
|
|
extern int split_vma(struct mm_struct *,
|
|
|
|
struct vm_area_struct *, unsigned long addr, int new_below);
|
|
|
|
extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
|
|
|
|
extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
|
|
|
|
struct rb_node **, struct rb_node *);
|
2005-10-30 01:15:57 +00:00
|
|
|
extern void unlink_file_vma(struct vm_area_struct *);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
|
2012-10-08 23:31:50 +00:00
|
|
|
unsigned long addr, unsigned long len, pgoff_t pgoff,
|
|
|
|
bool *need_rmap_locks);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern void exit_mmap(struct mm_struct *);
|
2008-04-29 08:01:36 +00:00
|
|
|
|
2014-10-09 22:27:29 +00:00
|
|
|
static inline int check_data_rlimit(unsigned long rlim,
|
|
|
|
unsigned long new,
|
|
|
|
unsigned long start,
|
|
|
|
unsigned long end_data,
|
|
|
|
unsigned long start_data)
|
|
|
|
{
|
|
|
|
if (rlim < RLIM_INFINITY) {
|
|
|
|
if (((new - start) + (end_data - start_data)) > rlim)
|
|
|
|
return -ENOSPC;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2008-07-28 22:46:26 +00:00
|
|
|
extern int mm_take_all_locks(struct mm_struct *mm);
|
|
|
|
extern void mm_drop_all_locks(struct mm_struct *mm);
|
|
|
|
|
2011-05-26 23:25:46 +00:00
|
|
|
extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
|
|
|
|
extern struct file *get_mm_exe_file(struct mm_struct *mm);
|
2008-04-29 08:01:36 +00:00
|
|
|
|
2005-05-01 15:58:35 +00:00
|
|
|
extern int may_expand_vm(struct mm_struct *mm, unsigned long npages);
|
2014-03-17 22:22:02 +00:00
|
|
|
extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
|
|
|
|
unsigned long addr, unsigned long len,
|
2014-05-19 22:58:33 +00:00
|
|
|
unsigned long flags,
|
|
|
|
const struct vm_special_mapping *spec);
|
|
|
|
/* This is an obsolete alternative to _install_special_mapping. */
|
2007-02-08 22:20:41 +00:00
|
|
|
extern int install_special_mapping(struct mm_struct *mm,
|
|
|
|
unsigned long addr, unsigned long len,
|
|
|
|
unsigned long flags, struct page **pages);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
|
|
|
|
|
2007-07-16 06:38:26 +00:00
|
|
|
extern unsigned long mmap_region(struct file *file, unsigned long addr,
|
2013-02-23 00:32:43 +00:00
|
|
|
unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
|
2013-02-23 00:32:37 +00:00
|
|
|
extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
|
|
|
|
unsigned long len, unsigned long prot, unsigned long flags,
|
2013-02-23 00:32:47 +00:00
|
|
|
unsigned long pgoff, unsigned long *populate);
|
2005-04-16 22:20:36 +00:00
|
|
|
extern int do_munmap(struct mm_struct *, unsigned long, size_t);
|
|
|
|
|
2013-02-23 00:32:37 +00:00
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
extern int __mm_populate(unsigned long addr, unsigned long len,
|
|
|
|
int ignore_errors);
|
|
|
|
static inline void mm_populate(unsigned long addr, unsigned long len)
|
|
|
|
{
|
|
|
|
/* Ignore errors */
|
|
|
|
(void) __mm_populate(addr, len, 1);
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
static inline void mm_populate(unsigned long addr, unsigned long len) {}
|
|
|
|
#endif
|
|
|
|
|
2012-04-20 22:35:40 +00:00
|
|
|
/* These take the mm semaphore themselves */
|
|
|
|
extern unsigned long vm_brk(unsigned long, unsigned long);
|
2012-04-21 01:57:04 +00:00
|
|
|
extern int vm_munmap(unsigned long, size_t);
|
2012-04-21 00:13:58 +00:00
|
|
|
extern unsigned long vm_mmap(struct file *, unsigned long,
|
|
|
|
unsigned long, unsigned long,
|
|
|
|
unsigned long, unsigned long);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2012-12-12 00:01:49 +00:00
|
|
|
struct vm_unmapped_area_info {
|
|
|
|
#define VM_UNMAPPED_AREA_TOPDOWN 1
|
|
|
|
unsigned long flags;
|
|
|
|
unsigned long length;
|
|
|
|
unsigned long low_limit;
|
|
|
|
unsigned long high_limit;
|
|
|
|
unsigned long align_mask;
|
|
|
|
unsigned long align_offset;
|
|
|
|
};
|
|
|
|
|
|
|
|
extern unsigned long unmapped_area(struct vm_unmapped_area_info *info);
|
|
|
|
extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Search for an unmapped address range.
|
|
|
|
*
|
|
|
|
* We are looking for a range that:
|
|
|
|
* - does not intersect with any VMA;
|
|
|
|
* - is contained within the [low_limit, high_limit) interval;
|
|
|
|
* - is at least the desired size.
|
|
|
|
* - satisfies (begin_addr & align_mask) == (align_offset & align_mask)
|
|
|
|
*/
|
|
|
|
static inline unsigned long
|
|
|
|
vm_unmapped_area(struct vm_unmapped_area_info *info)
|
|
|
|
{
|
2015-04-15 23:14:47 +00:00
|
|
|
if (info->flags & VM_UNMAPPED_AREA_TOPDOWN)
|
2012-12-12 00:01:49 +00:00
|
|
|
return unmapped_area_topdown(info);
|
2015-04-15 23:14:47 +00:00
|
|
|
else
|
|
|
|
return unmapped_area(info);
|
2012-12-12 00:01:49 +00:00
|
|
|
}
|
|
|
|
|
2011-07-26 00:12:23 +00:00
|
|
|
/* truncate.c */
|
2005-04-16 22:20:36 +00:00
|
|
|
extern void truncate_inode_pages(struct address_space *, loff_t);
|
2006-01-06 08:10:36 +00:00
|
|
|
extern void truncate_inode_pages_range(struct address_space *,
|
|
|
|
loff_t lstart, loff_t lend);
|
2014-04-03 21:47:49 +00:00
|
|
|
extern void truncate_inode_pages_final(struct address_space *);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* generic vm_area_ops exported for stackable file systems */
|
2007-07-19 08:47:03 +00:00
|
|
|
extern int filemap_fault(struct vm_area_struct *, struct vm_fault *);
|
2014-04-07 22:37:19 +00:00
|
|
|
extern void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf);
|
2012-06-12 14:20:29 +00:00
|
|
|
extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* mm/page-writeback.c */
|
|
|
|
int write_one_page(struct page *page, int wait);
|
2009-02-18 22:48:18 +00:00
|
|
|
void task_dirty_inc(struct task_struct *tsk);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* readahead.c */
|
|
|
|
#define VM_MAX_READAHEAD 128 /* kbytes */
|
|
|
|
#define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
|
|
|
|
|
|
|
|
int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
|
2005-11-07 08:59:28 +00:00
|
|
|
pgoff_t offset, unsigned long nr_to_read);
|
2007-07-19 08:48:08 +00:00
|
|
|
|
|
|
|
void page_cache_sync_readahead(struct address_space *mapping,
|
|
|
|
struct file_ra_state *ra,
|
|
|
|
struct file *filp,
|
|
|
|
pgoff_t offset,
|
|
|
|
unsigned long size);
|
|
|
|
|
|
|
|
void page_cache_async_readahead(struct address_space *mapping,
|
|
|
|
struct file_ra_state *ra,
|
|
|
|
struct file *filp,
|
|
|
|
struct page *pg,
|
|
|
|
pgoff_t offset,
|
|
|
|
unsigned long size);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
unsigned long max_sane_readahead(unsigned long nr);
|
|
|
|
|
2011-05-25 00:11:44 +00:00
|
|
|
/* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
|
2005-10-30 01:16:20 +00:00
|
|
|
extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
|
2011-05-25 00:11:44 +00:00
|
|
|
|
|
|
|
/* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */
|
|
|
|
extern int expand_downwards(struct vm_area_struct *vma,
|
|
|
|
unsigned long address);
|
2010-08-24 18:44:18 +00:00
|
|
|
#if VM_GROWSUP
|
2005-10-30 01:16:20 +00:00
|
|
|
extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
|
2010-08-24 18:44:18 +00:00
|
|
|
#else
|
2015-01-06 21:00:05 +00:00
|
|
|
#define expand_upwards(vma, address) (0)
|
2005-11-18 21:16:42 +00:00
|
|
|
#endif
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
|
|
|
|
extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
|
|
|
|
extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
|
|
|
|
struct vm_area_struct **pprev);
|
|
|
|
|
|
|
|
/* Look up the first VMA which intersects the interval start_addr..end_addr-1,
|
|
|
|
NULL if none. Assume start_addr < end_addr. */
|
|
|
|
static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
|
|
|
|
{
|
|
|
|
struct vm_area_struct * vma = find_vma(mm,start_addr);
|
|
|
|
|
|
|
|
if (vma && end_addr <= vma->vm_start)
|
|
|
|
vma = NULL;
|
|
|
|
return vma;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long vma_pages(struct vm_area_struct *vma)
|
|
|
|
{
|
|
|
|
return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
|
|
|
|
}
|
|
|
|
|
2012-01-10 23:11:23 +00:00
|
|
|
/* Look up the first VMA which exactly match the interval vm_start ... vm_end */
|
|
|
|
static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
|
|
|
|
unsigned long vm_start, unsigned long vm_end)
|
|
|
|
{
|
|
|
|
struct vm_area_struct *vma = find_vma(mm, vm_start);
|
|
|
|
|
|
|
|
if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
|
|
|
|
vma = NULL;
|
|
|
|
|
|
|
|
return vma;
|
|
|
|
}
|
|
|
|
|
2010-08-26 15:00:34 +00:00
|
|
|
#ifdef CONFIG_MMU
|
2006-07-26 20:39:49 +00:00
|
|
|
pgprot_t vm_get_page_prot(unsigned long vm_flags);
|
mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared
For VMAs that don't want write notifications, PTEs created for read faults
have their write bit set. If the read fault happens after VM_SOFTDIRTY is
cleared, then the PTE's softdirty bit will remain clear after subsequent
writes.
Here's a simple code snippet to demonstrate the bug:
char* m = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_SHARED, -1, 0);
system("echo 4 > /proc/$PPID/clear_refs"); /* clear VM_SOFTDIRTY */
assert(*m == '\0'); /* new PTE allows write access */
assert(!soft_dirty(x));
*m = 'x'; /* should dirty the page */
assert(soft_dirty(x)); /* fails */
With this patch, write notifications are enabled when VM_SOFTDIRTY is
cleared. Furthermore, to avoid unnecessary faults, write notifications
are disabled when VM_SOFTDIRTY is set.
As a side effect of enabling and disabling write notifications with
care, this patch fixes a bug in mprotect where vm_page_prot bits set by
drivers were zapped on mprotect. An analogous bug was fixed in mmap by
commit c9d0bf241451 ("mm: uncached vma support with writenotify").
Signed-off-by: Peter Feiner <pfeiner@google.com>
Reported-by: Peter Feiner <pfeiner@google.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Jamie Liu <jamieliu@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-13 22:55:46 +00:00
|
|
|
void vma_set_page_prot(struct vm_area_struct *vma);
|
2010-08-26 15:00:34 +00:00
|
|
|
#else
|
|
|
|
static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
|
|
|
|
{
|
|
|
|
return __pgprot(0);
|
|
|
|
}
|
mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared
For VMAs that don't want write notifications, PTEs created for read faults
have their write bit set. If the read fault happens after VM_SOFTDIRTY is
cleared, then the PTE's softdirty bit will remain clear after subsequent
writes.
Here's a simple code snippet to demonstrate the bug:
char* m = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_SHARED, -1, 0);
system("echo 4 > /proc/$PPID/clear_refs"); /* clear VM_SOFTDIRTY */
assert(*m == '\0'); /* new PTE allows write access */
assert(!soft_dirty(x));
*m = 'x'; /* should dirty the page */
assert(soft_dirty(x)); /* fails */
With this patch, write notifications are enabled when VM_SOFTDIRTY is
cleared. Furthermore, to avoid unnecessary faults, write notifications
are disabled when VM_SOFTDIRTY is set.
As a side effect of enabling and disabling write notifications with
care, this patch fixes a bug in mprotect where vm_page_prot bits set by
drivers were zapped on mprotect. An analogous bug was fixed in mmap by
commit c9d0bf241451 ("mm: uncached vma support with writenotify").
Signed-off-by: Peter Feiner <pfeiner@google.com>
Reported-by: Peter Feiner <pfeiner@google.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Jamie Liu <jamieliu@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-13 22:55:46 +00:00
|
|
|
static inline void vma_set_page_prot(struct vm_area_struct *vma)
|
|
|
|
{
|
|
|
|
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
|
|
|
|
}
|
2010-08-26 15:00:34 +00:00
|
|
|
#endif
|
|
|
|
|
2013-12-05 18:38:22 +00:00
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
2012-10-25 12:16:32 +00:00
|
|
|
unsigned long change_prot_numa(struct vm_area_struct *vma,
|
2012-10-25 12:16:32 +00:00
|
|
|
unsigned long start, unsigned long end);
|
|
|
|
#endif
|
|
|
|
|
2005-10-30 01:16:33 +00:00
|
|
|
struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
|
|
|
|
int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
|
|
|
|
unsigned long pfn, unsigned long size, pgprot_t);
|
2005-11-30 17:35:19 +00:00
|
|
|
int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
|
2007-02-12 08:51:36 +00:00
|
|
|
int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
|
|
|
|
unsigned long pfn);
|
2008-04-28 09:13:01 +00:00
|
|
|
int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
|
|
|
|
unsigned long pfn);
|
2013-04-16 20:45:37 +00:00
|
|
|
int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
|
|
|
|
|
2005-10-30 01:16:33 +00:00
|
|
|
|
2013-02-23 00:35:56 +00:00
|
|
|
struct page *follow_page_mask(struct vm_area_struct *vma,
|
|
|
|
unsigned long address, unsigned int foll_flags,
|
|
|
|
unsigned int *page_mask);
|
|
|
|
|
|
|
|
static inline struct page *follow_page(struct vm_area_struct *vma,
|
|
|
|
unsigned long address, unsigned int foll_flags)
|
|
|
|
{
|
|
|
|
unsigned int unused_page_mask;
|
|
|
|
return follow_page_mask(vma, address, foll_flags, &unused_page_mask);
|
|
|
|
}
|
|
|
|
|
2005-10-30 01:16:33 +00:00
|
|
|
#define FOLL_WRITE 0x01 /* check pte is writable */
|
|
|
|
#define FOLL_TOUCH 0x02 /* mark page accessed */
|
|
|
|
#define FOLL_GET 0x04 /* do get_page on page */
|
2009-09-22 00:03:26 +00:00
|
|
|
#define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
|
2009-09-22 00:03:31 +00:00
|
|
|
#define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
|
2011-03-22 23:30:51 +00:00
|
|
|
#define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO
|
|
|
|
* and return without waiting upon it */
|
2015-04-14 22:44:37 +00:00
|
|
|
#define FOLL_POPULATE 0x40 /* fault in page */
|
2011-01-13 23:46:55 +00:00
|
|
|
#define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */
|
2011-01-30 03:15:48 +00:00
|
|
|
#define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */
|
2012-10-05 19:36:27 +00:00
|
|
|
#define FOLL_NUMA 0x200 /* force NUMA hinting page fault */
|
mm,ksm: FOLL_MIGRATION do migration_entry_wait
In "ksm: remove old stable nodes more thoroughly" I said that I'd never
seen its WARN_ON_ONCE(page_mapped(page)). True at the time of writing,
but it soon appeared once I tried fuller tests on the whole series.
It turned out to be due to the KSM page migration itself: unmerge_and_
remove_all_rmap_items() failed to locate and replace all the KSM pages,
because of that hiatus in page migration when old pte has been replaced
by migration entry, but not yet by new pte. follow_page() finds no page
at that instant, but a KSM page reappears shortly after, without a
fault.
Add FOLL_MIGRATION flag, so follow_page() can do migration_entry_wait()
for KSM's break_cow(). I'd have preferred to avoid another flag, and do
it every time, in case someone else makes the same easy mistake; but did
not find another transgressor (the common get_user_pages() is of course
safe), and cannot be sure that every follow_page() caller is prepared to
sleep - ia64's xencomm_vtop()? Now, THP's wait_split_huge_page() can
already sleep there, since anon_vma locking was changed to mutex, but
maybe that's somehow excluded.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 00:36:07 +00:00
|
|
|
#define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */
|
2014-09-17 17:51:48 +00:00
|
|
|
#define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2008-02-08 12:22:04 +00:00
|
|
|
typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
|
2007-05-06 21:48:54 +00:00
|
|
|
void *data);
|
|
|
|
extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
|
|
|
|
unsigned long size, pte_fn_t fn, void *data);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#ifdef CONFIG_PROC_FS
|
2005-10-30 01:15:56 +00:00
|
|
|
void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long);
|
2005-04-16 22:20:36 +00:00
|
|
|
#else
|
2005-10-30 01:15:56 +00:00
|
|
|
static inline void vm_stat_account(struct mm_struct *mm,
|
2005-04-16 22:20:36 +00:00
|
|
|
unsigned long flags, struct file *file, long pages)
|
|
|
|
{
|
2012-07-31 23:41:49 +00:00
|
|
|
mm->total_vm += pages;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
|
2008-01-30 12:33:58 +00:00
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
2014-12-13 00:55:52 +00:00
|
|
|
extern bool _debug_pagealloc_enabled;
|
|
|
|
extern void __kernel_map_pages(struct page *page, int numpages, int enable);
|
|
|
|
|
|
|
|
static inline bool debug_pagealloc_enabled(void)
|
|
|
|
{
|
|
|
|
return _debug_pagealloc_enabled;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void
|
|
|
|
kernel_map_pages(struct page *page, int numpages, int enable)
|
|
|
|
{
|
|
|
|
if (!debug_pagealloc_enabled())
|
|
|
|
return;
|
|
|
|
|
|
|
|
__kernel_map_pages(page, numpages, enable);
|
|
|
|
}
|
2008-02-20 00:47:44 +00:00
|
|
|
#ifdef CONFIG_HIBERNATION
|
|
|
|
extern bool kernel_page_present(struct page *page);
|
|
|
|
#endif /* CONFIG_HIBERNATION */
|
2008-01-30 12:33:58 +00:00
|
|
|
#else
|
2005-04-16 22:20:36 +00:00
|
|
|
static inline void
|
2006-10-11 08:21:30 +00:00
|
|
|
kernel_map_pages(struct page *page, int numpages, int enable) {}
|
2008-02-20 00:47:44 +00:00
|
|
|
#ifdef CONFIG_HIBERNATION
|
|
|
|
static inline bool kernel_page_present(struct page *page) { return true; }
|
|
|
|
#endif /* CONFIG_HIBERNATION */
|
2005-04-16 22:20:36 +00:00
|
|
|
#endif
|
|
|
|
|
arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area
The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).
This default is only useful for ia64. arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it. arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.
This gets rid of the default and moves the code into ia64.
This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 21:23:40 +00:00
|
|
|
#ifdef __HAVE_ARCH_GATE_AREA
|
2011-03-13 19:49:15 +00:00
|
|
|
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
|
arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area
The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).
This default is only useful for ia64. arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it. arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.
This gets rid of the default and moves the code into ia64.
This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 21:23:40 +00:00
|
|
|
extern int in_gate_area_no_mm(unsigned long addr);
|
|
|
|
extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
|
2005-04-16 22:20:36 +00:00
|
|
|
#else
|
arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area
The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).
This default is only useful for ia64. arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it. arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.
This gets rid of the default and moves the code into ia64.
This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 21:23:40 +00:00
|
|
|
static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
|
|
|
|
{
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
|
|
|
|
static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
#endif /* __HAVE_ARCH_GATE_AREA */
|
|
|
|
|
2013-04-29 22:07:22 +00:00
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
extern int sysctl_drop_caches;
|
2009-09-23 22:57:19 +00:00
|
|
|
int drop_caches_sysctl_handler(struct ctl_table *, int,
|
2006-01-08 09:00:39 +00:00
|
|
|
void __user *, size_t *, loff_t *);
|
2013-04-29 22:07:22 +00:00
|
|
|
#endif
|
|
|
|
|
2015-02-12 22:58:54 +00:00
|
|
|
void drop_slab(void);
|
|
|
|
void drop_slab_node(int nid);
|
2006-01-08 09:00:39 +00:00
|
|
|
|
2006-02-21 02:28:07 +00:00
|
|
|
#ifndef CONFIG_MMU
|
|
|
|
#define randomize_va_space 0
|
|
|
|
#else
|
2006-02-16 22:41:58 +00:00
|
|
|
extern int randomize_va_space;
|
2006-02-21 02:28:07 +00:00
|
|
|
#endif
|
2006-02-16 22:41:58 +00:00
|
|
|
|
2007-07-26 17:41:13 +00:00
|
|
|
const char * arch_vma_name(struct vm_area_struct *vma);
|
2008-01-30 12:33:18 +00:00
|
|
|
void print_vma_addr(char *prefix, unsigned long rip);
|
[PATCH] vdso: randomize the i386 vDSO by moving it into a vma
Move the i386 VDSO down into a vma and thus randomize it.
Besides the security implications, this feature also helps debuggers, which
can COW a vma-backed VDSO just like a normal DSO and can thus do
single-stepping and other debugging features.
It's good for hypervisors (Xen, VMWare) too, which typically live in the same
high-mapped address space as the VDSO, hence whenever the VDSO is used, they
get lots of guest pagefaults and have to fix such guest accesses up - which
slows things down instead of speeding things up (the primary purpose of the
VDSO).
There's a new CONFIG_COMPAT_VDSO (default=y) option, which provides support
for older glibcs that still rely on a prelinked high-mapped VDSO. Newer
distributions (using glibc 2.3.3 or later) can turn this option off. Turning
it off is also recommended for security reasons: attackers cannot use the
predictable high-mapped VDSO page as syscall trampoline anymore.
There is a new vdso=[0|1] boot option as well, and a runtime
/proc/sys/vm/vdso_enabled sysctl switch, that allows the VDSO to be turned
on/off.
(This version of the VDSO-randomization patch also has working ELF
coredumping, the previous patch crashed in the coredumping code.)
This code is a combined work of the exec-shield VDSO randomization
code and Gerd Hoffmann's hypervisor-centric VDSO patch. Rusty Russell
started this patch and i completed it.
[akpm@osdl.org: cleanups]
[akpm@osdl.org: compile fix]
[akpm@osdl.org: compile fix 2]
[akpm@osdl.org: compile fix 3]
[akpm@osdl.org: revernt MAXMEM change]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Cc: Gerd Hoffmann <kraxel@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 09:53:50 +00:00
|
|
|
|
2010-02-10 09:20:22 +00:00
|
|
|
void sparse_mem_maps_populate_node(struct page **map_map,
|
|
|
|
unsigned long pnum_begin,
|
|
|
|
unsigned long pnum_end,
|
|
|
|
unsigned long map_count,
|
|
|
|
int nodeid);
|
|
|
|
|
2007-10-16 08:26:14 +00:00
|
|
|
struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
|
2007-10-16 08:24:14 +00:00
|
|
|
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
|
|
|
|
pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);
|
|
|
|
pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
|
|
|
|
pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
|
2007-10-16 08:24:13 +00:00
|
|
|
void *vmemmap_alloc_block(unsigned long size, int node);
|
2010-02-10 09:20:22 +00:00
|
|
|
void *vmemmap_alloc_block_buf(unsigned long size, int node);
|
2007-10-16 08:24:13 +00:00
|
|
|
void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
|
2013-04-29 22:07:50 +00:00
|
|
|
int vmemmap_populate_basepages(unsigned long start, unsigned long end,
|
|
|
|
int node);
|
|
|
|
int vmemmap_populate(unsigned long start, unsigned long end, int node);
|
2008-04-12 08:19:24 +00:00
|
|
|
void vmemmap_populate_print_last(void);
|
2013-02-23 00:33:08 +00:00
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
2013-04-29 22:07:50 +00:00
|
|
|
void vmemmap_free(unsigned long start, unsigned long end);
|
2013-02-23 00:33:08 +00:00
|
|
|
#endif
|
2013-02-23 00:33:00 +00:00
|
|
|
void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
|
|
|
|
unsigned long size);
|
2009-09-16 09:50:15 +00:00
|
|
|
|
2009-12-16 11:19:57 +00:00
|
|
|
enum mf_flags {
|
|
|
|
MF_COUNT_INCREASED = 1 << 0,
|
2011-12-13 17:27:58 +00:00
|
|
|
MF_ACTION_REQUIRED = 1 << 1,
|
2012-07-11 17:20:47 +00:00
|
|
|
MF_MUST_KILL = 1 << 2,
|
2013-07-10 09:27:01 +00:00
|
|
|
MF_SOFT_OFFLINE = 1 << 3,
|
2009-12-16 11:19:57 +00:00
|
|
|
};
|
2011-12-15 18:48:12 +00:00
|
|
|
extern int memory_failure(unsigned long pfn, int trapno, int flags);
|
2011-07-13 05:14:27 +00:00
|
|
|
extern void memory_failure_queue(unsigned long pfn, int trapno, int flags);
|
2009-12-16 11:19:58 +00:00
|
|
|
extern int unpoison_memory(unsigned long pfn);
|
2015-06-24 23:56:48 +00:00
|
|
|
extern int get_hwpoison_page(struct page *page);
|
2009-09-16 09:50:15 +00:00
|
|
|
extern int sysctl_memory_failure_early_kill;
|
|
|
|
extern int sysctl_memory_failure_recovery;
|
2009-12-16 11:20:00 +00:00
|
|
|
extern void shake_page(struct page *p, int access);
|
2013-02-23 00:34:02 +00:00
|
|
|
extern atomic_long_t num_poisoned_pages;
|
2009-12-16 11:20:00 +00:00
|
|
|
extern int soft_offline_page(struct page *page, int flags);
|
2009-09-16 09:50:15 +00:00
|
|
|
|
2015-06-24 23:57:30 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Error handlers for various types of pages.
|
|
|
|
*/
|
2015-06-24 23:57:33 +00:00
|
|
|
enum mf_result {
|
2015-06-24 23:57:30 +00:00
|
|
|
MF_IGNORED, /* Error: cannot be handled */
|
|
|
|
MF_FAILED, /* Error: handling failed */
|
|
|
|
MF_DELAYED, /* Will be handled later */
|
|
|
|
MF_RECOVERED, /* Successfully recovered */
|
|
|
|
};
|
|
|
|
|
|
|
|
enum mf_action_page_type {
|
|
|
|
MF_MSG_KERNEL,
|
|
|
|
MF_MSG_KERNEL_HIGH_ORDER,
|
|
|
|
MF_MSG_SLAB,
|
|
|
|
MF_MSG_DIFFERENT_COMPOUND,
|
|
|
|
MF_MSG_POISONED_HUGE,
|
|
|
|
MF_MSG_HUGE,
|
|
|
|
MF_MSG_FREE_HUGE,
|
|
|
|
MF_MSG_UNMAP_FAILED,
|
|
|
|
MF_MSG_DIRTY_SWAPCACHE,
|
|
|
|
MF_MSG_CLEAN_SWAPCACHE,
|
|
|
|
MF_MSG_DIRTY_MLOCKED_LRU,
|
|
|
|
MF_MSG_CLEAN_MLOCKED_LRU,
|
|
|
|
MF_MSG_DIRTY_UNEVICTABLE_LRU,
|
|
|
|
MF_MSG_CLEAN_UNEVICTABLE_LRU,
|
|
|
|
MF_MSG_DIRTY_LRU,
|
|
|
|
MF_MSG_CLEAN_LRU,
|
|
|
|
MF_MSG_TRUNCATED_LRU,
|
|
|
|
MF_MSG_BUDDY,
|
|
|
|
MF_MSG_BUDDY_2ND,
|
|
|
|
MF_MSG_UNKNOWN,
|
|
|
|
};
|
|
|
|
|
2011-01-13 23:46:47 +00:00
|
|
|
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
|
|
|
|
extern void clear_huge_page(struct page *page,
|
|
|
|
unsigned long addr,
|
|
|
|
unsigned int pages_per_huge_page);
|
|
|
|
extern void copy_user_huge_page(struct page *dst, struct page *src,
|
|
|
|
unsigned long addr, struct vm_area_struct *vma,
|
|
|
|
unsigned int pages_per_huge_page);
|
|
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
|
|
|
|
|
mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
|
|
|
extern struct page_ext_operations debug_guardpage_ops;
|
|
|
|
extern struct page_ext_operations page_poisoning_ops;
|
|
|
|
|
2012-01-10 23:07:28 +00:00
|
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
|
|
extern unsigned int _debug_guardpage_minorder;
|
mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
|
|
|
extern bool _debug_guardpage_enabled;
|
2012-01-10 23:07:28 +00:00
|
|
|
|
|
|
|
static inline unsigned int debug_guardpage_minorder(void)
|
|
|
|
{
|
|
|
|
return _debug_guardpage_minorder;
|
|
|
|
}
|
|
|
|
|
mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
|
|
|
static inline bool debug_guardpage_enabled(void)
|
|
|
|
{
|
|
|
|
return _debug_guardpage_enabled;
|
|
|
|
}
|
|
|
|
|
2012-01-10 23:07:28 +00:00
|
|
|
static inline bool page_is_guard(struct page *page)
|
|
|
|
{
|
mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
|
|
|
struct page_ext *page_ext;
|
|
|
|
|
|
|
|
if (!debug_guardpage_enabled())
|
|
|
|
return false;
|
|
|
|
|
|
|
|
page_ext = lookup_page_ext(page);
|
|
|
|
return test_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
|
2012-01-10 23:07:28 +00:00
|
|
|
}
|
|
|
|
#else
|
|
|
|
static inline unsigned int debug_guardpage_minorder(void) { return 0; }
|
mm/debug-pagealloc: prepare boottime configurable on/off
Until now, debug-pagealloc needs extra flags in struct page, so we need to
recompile whole source code when we decide to use it. This is really
painful, because it takes some time to recompile and sometimes rebuild is
not possible due to third party module depending on struct page. So, we
can't use this good feature in many cases.
Now, we have the page extension feature that allows us to insert extra
flags to outside of struct page. This gets rid of third party module
issue mentioned above. And, this allows us to determine if we need extra
memory for this page extension in boottime. With these property, we can
avoid using debug-pagealloc in boottime with low computational overhead in
the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our
development process greatly.
This patch is the preparation step to achive above goal. debug-pagealloc
originally uses extra field of struct page, but, after this patch, it will
use field of struct page_ext. Because memory for page_ext is allocated
later than initialization of page allocator in CONFIG_SPARSEMEM, we should
disable debug-pagealloc feature temporarily until initialization of
page_ext. This patch implements this.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 00:55:49 +00:00
|
|
|
static inline bool debug_guardpage_enabled(void) { return false; }
|
2012-01-10 23:07:28 +00:00
|
|
|
static inline bool page_is_guard(struct page *page) { return false; }
|
|
|
|
#endif /* CONFIG_DEBUG_PAGEALLOC */
|
|
|
|
|
2013-04-29 22:08:01 +00:00
|
|
|
#if MAX_NUMNODES > 1
|
|
|
|
void __init setup_nr_node_ids(void);
|
|
|
|
#else
|
|
|
|
static inline void setup_nr_node_ids(void) {}
|
|
|
|
#endif
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* _LINUX_MM_H */
|