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17840 commits

Author SHA1 Message Date
Linus Torvalds
9030fb0bb9 Folio changes for 5.18
- Rewrite how munlock works to massively reduce the contention
    on i_mmap_rwsem (Hugh Dickins):
    https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/
  - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph Hellwig):
    https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/
  - Convert GUP to use folios and make pincount available for order-1
    pages. (Matthew Wilcox)
  - Convert a few more truncation functions to use folios (Matthew Wilcox)
  - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew Wilcox)
  - Convert rmap_walk to use folios (Matthew Wilcox)
  - Convert most of shrink_page_list() to use a folio (Matthew Wilcox)
  - Add support for creating large folios in readahead (Matthew Wilcox)
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Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache

Pull folio updates from Matthew Wilcox:

 - Rewrite how munlock works to massively reduce the contention on
   i_mmap_rwsem (Hugh Dickins):

     https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/

 - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph
   Hellwig):

     https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/

 - Convert GUP to use folios and make pincount available for order-1
   pages. (Matthew Wilcox)

 - Convert a few more truncation functions to use folios (Matthew
   Wilcox)

 - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew
   Wilcox)

 - Convert rmap_walk to use folios (Matthew Wilcox)

 - Convert most of shrink_page_list() to use a folio (Matthew Wilcox)

 - Add support for creating large folios in readahead (Matthew Wilcox)

* tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits)
  mm/damon: minor cleanup for damon_pa_young
  selftests/vm/transhuge-stress: Support file-backed PMD folios
  mm/filemap: Support VM_HUGEPAGE for file mappings
  mm/readahead: Switch to page_cache_ra_order
  mm/readahead: Align file mappings for non-DAX
  mm/readahead: Add large folio readahead
  mm: Support arbitrary THP sizes
  mm: Make large folios depend on THP
  mm: Fix READ_ONLY_THP warning
  mm/filemap: Allow large folios to be added to the page cache
  mm: Turn can_split_huge_page() into can_split_folio()
  mm/vmscan: Convert pageout() to take a folio
  mm/vmscan: Turn page_check_references() into folio_check_references()
  mm/vmscan: Account large folios correctly
  mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios
  mm/vmscan: Free non-shmem folios without splitting them
  mm/rmap: Constify the rmap_walk_control argument
  mm/rmap: Convert rmap_walk() to take a folio
  mm: Turn page_anon_vma() into folio_anon_vma()
  mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()
  ...
2022-03-22 17:03:12 -07:00
Linus Torvalds
3bf03b9a08 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs

 - Most the MM patches which precede the patches in Willy's tree: kasan,
   pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
   sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb,
   userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp,
   cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap,
   zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits)
  mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release()
  Docs/ABI/testing: add DAMON sysfs interface ABI document
  Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface
  selftests/damon: add a test for DAMON sysfs interface
  mm/damon/sysfs: support DAMOS stats
  mm/damon/sysfs: support DAMOS watermarks
  mm/damon/sysfs: support schemes prioritization
  mm/damon/sysfs: support DAMOS quotas
  mm/damon/sysfs: support DAMON-based Operation Schemes
  mm/damon/sysfs: support the physical address space monitoring
  mm/damon/sysfs: link DAMON for virtual address spaces monitoring
  mm/damon: implement a minimal stub for sysfs-based DAMON interface
  mm/damon/core: add number of each enum type values
  mm/damon/core: allow non-exclusive DAMON start/stop
  Docs/damon: update outdated term 'regions update interval'
  Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling
  Docs/vm/damon: call low level monitoring primitives the operations
  mm/damon: remove unnecessary CONFIG_DAMON option
  mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}()
  mm/damon/dbgfs-test: fix is_target_id() change
  ...
2022-03-22 16:11:53 -07:00
Xin Hao
15423a52cc mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release()
In damon_sysfs_kdamond_release(), we have use container_of() to get
"kdamond" pointer, so there no need to get it once again.

Link: https://lkml.kernel.org/r/20220303075314.22502-1-xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
0ac32b8aff mm/damon/sysfs: support DAMOS stats
This commit makes DAMON sysfs interface supports the DAMOS stats feature.
Specifically, this commit adds 'stats' directory under each scheme
directory, and update the contents of the files under the directory
according to the latest monitoring results, when the user writes special
keyword, 'update_schemes_stats' to the 'state' file of the kdamond.

As a result, the files hierarchy becomes as below:

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr_schemes
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ │ quotas/ms,sz,reset_interval_ms
    │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil
    │ │ │ │ │ │ │ watermarks/metric,interval_us,high,mid,low
    │ │ │ │ │ │ │ stats/    <- NEW DIRECTORY
    │ │ │ │ │ │ │ │ nr_tried,sz_tried,nr_applied,sz_applied,qt_exceeds
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Link: https://lkml.kernel.org/r/20220228081314.5770-11-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
1b32234ab0 mm/damon/sysfs: support DAMOS watermarks
This commit makes DAMON sysfs interface supports the DAMOS watermarks
feature.  Specifically, this commit adds 'watermarks' directory under each
scheme directory and makes kdamond 'state' file writing respects the
contents in the directory.

As a result, the files hierarchy becomes as below:

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr_schemes
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ │ quotas/ms,sz,reset_interval_ms
    │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil
    │ │ │ │ │ │ │ watermarks/    <- NEW DIRECTORY
    │ │ │ │ │ │ │ │ metric,interval_us,high,mid,lo
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

[sj@kernel.org: fix out-of-bound array access for wmark_metric_strs[]]
  Link: https://lkml.kernel.org/r/20220301185619.2904-1-sj@kernel.org

Link: https://lkml.kernel.org/r/20220228081314.5770-10-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
1c78b2bcd2 mm/damon/sysfs: support schemes prioritization
This commit makes DAMON sysfs interface supports the DAMOS' regions
prioritization weights feature under quotas limitation.  Specifically,
this commit adds 'weights' directory under each scheme directory and makes
kdamond 'state' file writing respects the contents in the directory.

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr
    │ │ 0/state,pid
    │ │ │ contexts/nr
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr
    │ │ │ │ │ │ 0/pid
    │ │ │ │ │ │ │ regions/nr
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ │ quotas/ms,bytes,reset_interval_ms
    │ │ │ │ │ │ │ │ weights/    <- NEW DIRECTORY
    │ │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Link: https://lkml.kernel.org/r/20220228081314.5770-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
9bbb820a5b mm/damon/sysfs: support DAMOS quotas
This commit makes DAMON sysfs interface supports the DAMOS quotas feature.
Specifically, this commit adds 'quotas' directory under each scheme
directory and makes kdamond 'state' file writing respects the contents in
the directory.

As a result, the files hierarchy becomes as below:

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr_schemes
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ │ quotas/ms,bytes,reset_interval_ms    <- NEW DIRECTORY
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Link: https://lkml.kernel.org/r/20220228081314.5770-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
7e84b1f821 mm/damon/sysfs: support DAMON-based Operation Schemes
This commit makes DAMON sysfs interface supports the DAMON-based operation
schemes (DAMOS) feature.  Specifically, this commit adds 'schemes'
directory under each context direcotry, and makes kdamond 'state' file
writing respects the contents in the directory.

Note that this commit doesn't support all features of DAMOS but only the
target access pattern and action feature.  Supports for quotas,
prioritization, watermarks will follow.

As a result, the files hierarchy becomes as below:

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr_schemes    <- NEW DIRECTORY
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Link: https://lkml.kernel.org/r/20220228081314.5770-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
2031b14ea7 mm/damon/sysfs: support the physical address space monitoring
This commit makes DAMON sysfs interface supports the physical address
space monitoring.  Specifically, this commit adds support of the initial
monitoring regions set feature by adding 'regions' directory under each
target directory and makes context operations file to receive 'paddr' in
addition to 'vaddr'.

As a result, the files hierarchy becomes as below:

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/
    │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions    <- NEW DIRECTORY
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Link: https://lkml.kernel.org/r/20220228081314.5770-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
a61ea561c8 mm/damon/sysfs: link DAMON for virtual address spaces monitoring
This commit links the DAMON sysfs interface to DAMON so that users can
control DAMON via the interface.  In detail, this commit makes writing
'on' to 'state' file constructs DAMON contexts based on values that users
have written to relevant sysfs files and start the context.  It supports
only virtual address spaces monitoring at the moment, though.

The files hierarchy of DAMON sysfs interface after this commit is shown
below.  In the below figure, parents-children relations are represented
with indentations, each directory is having ``/`` suffix, and files in
each directory are separated by comma (",").

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/
    │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

The usage is straightforward.  Writing a number ('N') to each 'nr_*' file
makes directories named '0' to 'N-1'.  Users can construct DAMON contexts
by writing proper values to the files in the straightforward manner and
start each kdamond by writing 'on' to 'kdamonds/<N>/state'.

Link: https://lkml.kernel.org/r/20220228081314.5770-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
c951cd3b89 mm/damon: implement a minimal stub for sysfs-based DAMON interface
DAMON's debugfs-based user interface served very well, so far.  However,
it unnecessarily depends on debugfs, while DAMON is not aimed to be used
for only debugging.  Also, the interface receives multiple values via one
file.  For example, schemes file receives 18 values separated by white
spaces.  As a result, it is ineffient, hard to be used, and difficult to
be extended.  Especially, keeping backward compatibility of user space
tools is getting only challenging.  It would be better to implement
another reliable and flexible interface and deprecate the debugfs
interface in long term.

To this end, this commit implements a stub of a part of the new user
interface of DAMON using sysfs.  Specifically, this commit implements the
sysfs control parts for virtual address space monitoring.

More specifically, the idea of the new interface is, using directory
hierarchies and making one file for one value.  The hierarchy that this
commit is introducing is as below.  In the below figure, parents-children
relations are represented with indentations, each directory is having
``/`` suffix, and files in each directory are separated by comma (",").

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/
    │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Writing a number <N> to each 'nr' file makes directories of name <0> to
<N-1> in the directory of the 'nr' file.  That's all this commit does.
Writing proper values to relevant files will construct the DAMON contexts,
and writing a special keyword, 'on', to 'state' files for each kdamond
will ask DAMON to start the constructed contexts.

For a short example, using below commands for monitoring virtual address
spaces of a given workload is imaginable:

    # cd /sys/kernel/mm/damon/admin/
    # echo 1 > kdamonds/nr_kdamonds
    # echo 1 > kdamonds/0/contexts/nr_contexts
    # echo vaddr > kdamonds/0/contexts/0/operations
    # echo 1 > kdamonds/0/contexts/0/targets/nr_targets
    # echo $(pidof <workload>) > kdamonds/0/contexts/0/targets/0/pid_target
    # echo on > kdamonds/0/state

Please note that this commit is implementing only the sysfs part stub as
abovely mentioned.  This commit doesn't implement the special keywords for
'state' files.  Following commits will do that.

[jiapeng.chong@linux.alibaba.com: fix missing error code in damon_sysfs_attrs_add_dirs()]
  Link: https://lkml.kernel.org/r/20220302111120.24984-1-jiapeng.chong@linux.alibaba.com

Link: https://lkml.kernel.org/r/20220228081314.5770-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
SeongJae Park
8b9b0d335a mm/damon/core: allow non-exclusive DAMON start/stop
Patch series "Introduce DAMON sysfs interface", v3.

Introduction
============

DAMON's debugfs-based user interface (DAMON_DBGFS) served very well, so
far.  However, it unnecessarily depends on debugfs, while DAMON is not
aimed to be used for only debugging.  Also, the interface receives
multiple values via one file.  For example, schemes file receives 18
values.  As a result, it is inefficient, hard to be used, and difficult to
be extended.  Especially, keeping backward compatibility of user space
tools is getting only challenging.  It would be better to implement
another reliable and flexible interface and deprecate DAMON_DBGFS in long
term.

For the reason, this patchset introduces a sysfs-based new user interface
of DAMON.  The idea of the new interface is, using directory hierarchies
and having one dedicated file for each value.  For a short example, users
can do the virtual address monitoring via the interface as below:

    # cd /sys/kernel/mm/damon/admin/
    # echo 1 > kdamonds/nr_kdamonds
    # echo 1 > kdamonds/0/contexts/nr_contexts
    # echo vaddr > kdamonds/0/contexts/0/operations
    # echo 1 > kdamonds/0/contexts/0/targets/nr_targets
    # echo $(pidof <workload>) > kdamonds/0/contexts/0/targets/0/pid_target
    # echo on > kdamonds/0/state

A brief representation of the files hierarchy of DAMON sysfs interface is
as below.  Childs are represented with indentation, directories are having
'/' suffix, and files in each directory are separated by comma.

    /sys/kernel/mm/damon/admin
    │ kdamonds/nr_kdamonds
    │ │ 0/state,pid
    │ │ │ contexts/nr_contexts
    │ │ │ │ 0/operations
    │ │ │ │ │ monitoring_attrs/
    │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
    │ │ │ │ │ │ nr_regions/min,max
    │ │ │ │ │ targets/nr_targets
    │ │ │ │ │ │ 0/pid_target
    │ │ │ │ │ │ │ regions/nr_regions
    │ │ │ │ │ │ │ │ 0/start,end
    │ │ │ │ │ │ │ │ ...
    │ │ │ │ │ │ ...
    │ │ │ │ │ schemes/nr_schemes
    │ │ │ │ │ │ 0/action
    │ │ │ │ │ │ │ access_pattern/
    │ │ │ │ │ │ │ │ sz/min,max
    │ │ │ │ │ │ │ │ nr_accesses/min,max
    │ │ │ │ │ │ │ │ age/min,max
    │ │ │ │ │ │ │ quotas/ms,bytes,reset_interval_ms
    │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil
    │ │ │ │ │ │ │ watermarks/metric,interval_us,high,mid,low
    │ │ │ │ │ │ │ stats/nr_tried,sz_tried,nr_applied,sz_applied,qt_exceeds
    │ │ │ │ │ │ ...
    │ │ │ │ ...
    │ │ ...

Detailed usage of the files will be described in the final Documentation
patch of this patchset.

Main Difference Between DAMON_DBGFS and DAMON_SYSFS
---------------------------------------------------

At the moment, DAMON_DBGFS and DAMON_SYSFS provides same features.  One
important difference between them is their exclusiveness.  DAMON_DBGFS
works in an exclusive manner, so that no DAMON worker thread (kdamond) in
the system can run concurrently and interfere somehow.  For the reason,
DAMON_DBGFS asks users to construct all monitoring contexts and start them
at once.  It's not a big problem but makes the operation a little bit
complex and unflexible.

For more flexible usage, DAMON_SYSFS moves the responsibility of
preventing any possible interference to the admins and work in a
non-exclusive manner.  That is, users can configure and start contexts one
by one.  Note that DAMON respects both exclusive groups and non-exclusive
groups of contexts, in a manner similar to that of reader-writer locks.
That is, if any exclusive monitoring contexts (e.g., contexts that started
via DAMON_DBGFS) are running, DAMON_SYSFS does not start new contexts, and
vice versa.

Future Plan of DAMON_DBGFS Deprecation
======================================

Once this patchset is merged, DAMON_DBGFS development will be frozen.
That is, we will maintain it to work as is now so that no users will be
break.  But, it will not be extended to provide any new feature of DAMON.
The support will be continued only until next LTS release.  After that, we
will drop DAMON_DBGFS.

User-space Tooling Compatibility
--------------------------------

As DAMON_SYSFS provides all features of DAMON_DBGFS, all user space
tooling can move to DAMON_SYSFS.  As we will continue supporting
DAMON_DBGFS until next LTS kernel release, user space tools would have
enough time to move to DAMON_SYSFS.

The official user space tool, damo[1], is already supporting both
DAMON_SYSFS and DAMON_DBGFS.  Both correctness tests[2] and performance
tests[3] of DAMON using DAMON_SYSFS also passed.

[1] https://github.com/awslabs/damo
[2] https://github.com/awslabs/damon-tests/tree/master/corr
[3] https://github.com/awslabs/damon-tests/tree/master/perf

Sequence of Patches
===================

First two patches (patches 1-2) make core changes for DAMON_SYSFS.  The
first one (patch 1) allows non-exclusive DAMON contexts so that
DAMON_SYSFS can work in non-exclusive mode, while the second one (patch 2)
adds size of DAMON enum types so that DAMON API users can safely iterate
the enums.

Third patch (patch 3) implements basic sysfs stub for virtual address
spaces monitoring.  Note that this implements only sysfs files and DAMON
is not linked.  Fourth patch (patch 4) links the DAMON_SYSFS to DAMON so
that users can control DAMON using the sysfs files.

Following six patches (patches 5-10) implements other DAMON features that
DAMON_DBGFS supports one by one (physical address space monitoring,
DAMON-based operation schemes, schemes quotas, schemes prioritization
weights, schemes watermarks, and schemes stats).

Following patch (patch 11) adds a simple selftest for DAMON_SYSFS, and the
final one (patch 12) documents DAMON_SYSFS.

This patch (of 13):

To avoid interference between DAMON contexts monitoring overlapping memory
regions, damon_start() works in an exclusive manner.  That is,
damon_start() does nothing bug fails if any context that started by
another instance of the function is still running.  This makes its usage a
little bit restrictive.  However, admins could aware each DAMON usage and
address such interferences on their own in some cases.

This commit hence implements non-exclusive mode of the function and allows
the callers to select the mode.  Note that the exclusive groups and
non-exclusive groups of contexts will respect each other in a manner
similar to that of reader-writer locks.  Therefore, this commit will not
cause any behavioral change to the exclusive groups.

Link: https://lkml.kernel.org/r/20220228081314.5770-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220228081314.5770-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:13 -07:00
tangmeng
3213a3c10f mm/damon: remove unnecessary CONFIG_DAMON option
In mm/Makefile has:

  obj-$(CONFIG_DAMON) += damon/

So that we don't need 'obj-$(CONFIG_DAMON) :=' in mm/damon/Makefile,
delete it from mm/damon/Makefile.

Link: https://lkml.kernel.org/r/20220221065255.19991-1-tangmeng@uniontech.com
Signed-off-by: tangmeng <tangmeng@uniontech.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
851040566a mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}()
Because DAMON debugfs interface and DAMON-based proactive reclaim are now
using monitoring operations via registration mechanism,
damon_{p,v}a_{target_valid,set_operations}() functions have no user.  This
commit clean them up.

Link: https://lkml.kernel.org/r/20220215184603.1479-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
999b946797 mm/damon/dbgfs-test: fix is_target_id() change
DAMON kunit tests for DAMON debugfs interface fails because it still
assumes setting empty monitoring operations makes DAMON debugfs interface
believe the target of the context don't have pid.  This commit fixes the
kunit test fails by explicitly setting the context's monitoring operations
with the operations for the physical address space, which let debugfs
knows the target will not have pid.

Link: https://lkml.kernel.org/r/20220215184603.1479-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
4a20865b07 mm/damon/dbgfs: use operations id for knowing if the target has pid
DAMON debugfs interface depends on monitoring operations for virtual
address spaces because it knows if the target has pid or not by seeing if
the context is configured to use one of the virtual address space
monitoring operation functions.  We can replace that check with 'enum
damon_ops_id' now, to make it independent.  This commit makes the change.

Link: https://lkml.kernel.org/r/20220215184603.1479-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
da7aaca05f mm/damon/dbgfs: use damon_select_ops() instead of damon_{v,p}a_set_operations()
This commit makes DAMON debugfs interface to select the registered
monitoring operations for the physical address space or virtual address
spaces depending on user requests instead of setting it on its own.  Note
that DAMON debugfs interface is still dependent to DAMON_VADDR with this
change, because it is also using its symbol, 'damon_va_target_valid'.

Link: https://lkml.kernel.org/r/20220215184603.1479-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
4d69c34578 mm/damon/reclaim: use damon_select_ops() instead of damon_{v,p}a_set_operations()
This commit makes DAMON_RECLAIM to select the registered monitoring
operations for the physical address space instead of setting it on its
own.  This allows DAMON_RECLAIM be independent of DAMON_PADDR, but leave
the dependency as is, because it's the only one monitoring operations it
use, and therefore it makes no sense to build DAMON_RECLAIM without
DAMON_PADDR.

Link: https://lkml.kernel.org/r/20220215184603.1479-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
7752925fbc mm/damon/paddr,vaddr: register themselves to DAMON in subsys_initcall
This commit makes the monitoring operations for the physical address space
and virtual address spaces register themselves to DAMON in the
subsys_initcall step.  Later, in-kernel DAMON user code can use them via
damon_select_ops() without have to unnecessarily depend on all possible
monitoring operations implementations.

Link: https://lkml.kernel.org/r/20220215184603.1479-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
9f7b053a0f mm/damon: let monitoring operations can be registered and selected
In-kernel DAMON user code like DAMON debugfs interface should set 'struct
damon_operations' of its 'struct damon_ctx' on its own.  Therefore, the
client code should depend on all supporting monitoring operations
implementations that it could use.  For example, DAMON debugfs interface
depends on both vaddr and paddr, while some of the users are not always
interested in both.

To minimize such unnecessary dependencies, this commit makes the
monitoring operations can be registered by implementing code and then
dynamically selected by the user code without build-time dependency.

Link: https://lkml.kernel.org/r/20220215184603.1479-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
f7d911c39c mm/damon: rename damon_primitives to damon_operations
Patch series "Allow DAMON user code independent of monitoring primitives".

In-kernel DAMON user code is required to configure the monitoring context
(struct damon_ctx) with proper monitoring primitives (struct
damon_primitive).  This makes the user code dependent to all supporting
monitoring primitives.  For example, DAMON debugfs interface depends on
both DAMON_VADDR and DAMON_PADDR, though some users have interest in only
one use case.  As more monitoring primitives are introduced, the problem
will be bigger.

To minimize such unnecessary dependency, this patchset makes monitoring
primitives can be registered by the implemnting code and later dynamically
searched and selected by the user code.

In addition to that, this patchset renames monitoring primitives to
monitoring operations, which is more easy to intuitively understand what
it means and how it would be structed.

This patch (of 8):

DAMON has a set of callback functions called monitoring primitives and let
it can be configured with various implementations for easy extension for
different address spaces and usages.  However, the word 'primitive' is not
so explicit.  Meanwhile, many other structs resembles similar purpose
calls themselves 'operations'.  To make the code easier to be understood,
this commit renames 'damon_primitives' to 'damon_operations' before it is
too late to rename.

Link: https://lkml.kernel.org/r/20220215184603.1479-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220215184603.1479-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Xin Hao <xhao@linux.alibaba.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>
2022-03-22 15:57:12 -07:00
Baolin Wang
242e10a09f mm/damon: remove redundant page validation
It will never get a NULL page by pte_page() as discussed in thread [1],
thus remove the redundant page validation to fix below Smatch static
checker warning.

    mm/damon/vaddr.c:405 damon_hugetlb_mkold()
    warn: 'page' can't be NULL.

[1] https://lore.kernel.org/linux-mm/20220106091200.GA14564@kili/

Link: https://lkml.kernel.org/r/6d32f7d201b8970d53f51b6c5717d472aed2987c.1642386715.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
1971bd6304 mm/damon: remove the target id concept
DAMON asks each monitoring target ('struct damon_target') to have one
'unsigned long' integer called 'id', which should be unique among the
targets of same monitoring context.  Meaning of it is, however, totally up
to the monitoring primitives that registered to the monitoring context.
For example, the virtual address spaces monitoring primitives treats the
id as a 'struct pid' pointer.

This makes the code flexible, but ugly, not well-documented, and
type-unsafe[1].  Also, identification of each target can be done via its
index.  For the reason, this commit removes the concept and uses clear
type definition.  For now, only 'struct pid' pointer is used for the
virtual address spaces monitoring.  If DAMON is extended in future so that
we need to put another identifier field in the struct, we will use a union
for such primitives-dependent fields and document which primitives are
using which type.

[1] https://lore.kernel.org/linux-mm/20211013154535.4aaeaaf9d0182922e405dd1e@linux-foundation.org/

Link: https://lkml.kernel.org/r/20211230100723.2238-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
436428255d mm/damon/core: move damon_set_targets() into dbgfs
damon_set_targets() function is defined in the core for general use cases,
but called from only dbgfs.  Also, because the function is for general use
cases, dbgfs does additional handling of pid type target id case.  To make
the situation simpler, this commit moves the function into dbgfs and makes
it to do the pid type case handling on its own.

Link: https://lkml.kernel.org/r/20211230100723.2238-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
SeongJae Park
144760f8e0 mm/damon/dbgfs/init_regions: use target index instead of target id
Patch series "Remove the type-unclear target id concept".

DAMON asks each monitoring target ('struct damon_target') to have one
'unsigned long' integer called 'id', which should be unique among the
targets of same monitoring context.  Meaning of it is, however, totally up
to the monitoring primitives that registered to the monitoring context.
For example, the virtual address spaces monitoring primitives treats the
id as a 'struct pid' pointer.

This makes the code flexible but ugly, not well-documented, and
type-unsafe[1].  Also, identification of each target can be done via its
index.  For the reason, this patchset removes the concept and uses clear
type definition.

[1] https://lore.kernel.org/linux-mm/20211013154535.4aaeaaf9d0182922e405dd1e@linux-foundation.org/

This patch (of 4):

Target id is a 'unsigned long' data, which can be interpreted differently
by each monitoring primitives.  For example, it means 'struct pid *' for
the virtual address spaces monitoring, while it means nothing but an
integer to be displayed to debugfs interface users for the physical
address space monitoring.  It's flexible but makes code ugly and
type-unsafe[1].

To be prepared for eventual removal of the concept, this commit removes a
use case of the concept in 'init_regions' debugfs file handling.  In
detail, this commit replaces use of the id with the index of each target
in the context's targets list.

[1] https://lore.kernel.org/linux-mm/20211013154535.4aaeaaf9d0182922e405dd1e@linux-foundation.org/

Link: https://lkml.kernel.org/r/20211230100723.2238-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211230100723.2238-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
Miaohe Lin
d0977efab8 mm/hmm.c: remove unneeded local variable ret
The local variable ret is always 0. Remove it to make code more tight.

Link: https://lkml.kernel.org/r/20220125124833.39718-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:12 -07:00
Marco Elver
737b6a10ac kfence: allow use of a deferrable timer
Allow the use of a deferrable timer, which does not force CPU wake-ups
when the system is idle.  A consequence is that the sample interval
becomes very unpredictable, to the point that it is not guaranteed that
the KFENCE KUnit test still passes.

Nevertheless, on power-constrained systems this may be preferable, so
let's give the user the option should they accept the above trade-off.

Link: https://lkml.kernel.org/r/20220308141415.3168078-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Peng Liu
3cb1c9620e kfence: test: try to avoid test_gfpzero trigger rcu_stall
When CONFIG_KFENCE_NUM_OBJECTS is set to a big number, kfence
kunit-test-case test_gfpzero will eat up nearly all the CPU's resources
and rcu_stall is reported as the following log which is cut from a
physical server.

  rcu: INFO: rcu_sched self-detected stall on CPU
  rcu: 	68-....: (14422 ticks this GP) idle=6ce/1/0x4000000000000002
  softirq=592/592 fqs=7500 (t=15004 jiffies g=10677 q=20019)
  Task dump for CPU 68:
  task:kunit_try_catch state:R  running task
  stack:    0 pid: 9728 ppid:     2 flags:0x0000020a
  Call trace:
   dump_backtrace+0x0/0x1e4
   show_stack+0x20/0x2c
   sched_show_task+0x148/0x170
   ...
   rcu_sched_clock_irq+0x70/0x180
   update_process_times+0x68/0xb0
   tick_sched_handle+0x38/0x74
   ...
   gic_handle_irq+0x78/0x2c0
   el1_irq+0xb8/0x140
   kfree+0xd8/0x53c
   test_alloc+0x264/0x310 [kfence_test]
   test_gfpzero+0xf4/0x840 [kfence_test]
   kunit_try_run_case+0x48/0x20c
   kunit_generic_run_threadfn_adapter+0x28/0x34
   kthread+0x108/0x13c
   ret_from_fork+0x10/0x18

To avoid rcu_stall and unacceptable latency, a schedule point is
added to test_gfpzero.

Link: https://lkml.kernel.org/r/20220309083753.1561921-4-liupeng256@huawei.com
Signed-off-by: Peng Liu <liupeng256@huawei.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Wang Kefeng <wangkefeng.wang@huawei.com>
Cc: Daniel Latypov <dlatypov@google.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Peng Liu
adf5054570 kunit: fix UAF when run kfence test case test_gfpzero
Patch series "kunit: fix a UAF bug and do some optimization", v2.

This series is to fix UAF (use after free) when running kfence test case
test_gfpzero, which is time costly.  This UAF bug can be easily triggered
by setting CONFIG_KFENCE_NUM_OBJECTS = 65535.  Furthermore, some
optimization for kunit tests has been done.

This patch (of 3):

Kunit will create a new thread to run an actual test case, and the main
process will wait for the completion of the actual test thread until
overtime.  The variable "struct kunit test" has local property in function
kunit_try_catch_run, and will be used in the test case thread.  Task
kunit_try_catch_run will free "struct kunit test" when kunit runs
overtime, but the actual test case is still run and an UAF bug will be
triggered.

The above problem has been both observed in a physical machine and qemu
platform when running kfence kunit tests.  The problem can be triggered
when setting CONFIG_KFENCE_NUM_OBJECTS = 65535.  Under this setting, the
test case test_gfpzero will cost hours and kunit will run to overtime.
The follows show the panic log.

  BUG: unable to handle page fault for address: ffffffff82d882e9

  Call Trace:
   kunit_log_append+0x58/0xd0
   ...
   test_alloc.constprop.0.cold+0x6b/0x8a [kfence_test]
   test_gfpzero.cold+0x61/0x8ab [kfence_test]
   kunit_try_run_case+0x4c/0x70
   kunit_generic_run_threadfn_adapter+0x11/0x20
   kthread+0x166/0x190
   ret_from_fork+0x22/0x30
  Kernel panic - not syncing: Fatal exception
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
  Ubuntu-1.8.2-1ubuntu1 04/01/2014

To solve this problem, the test case thread should be stopped when the
kunit frame runs overtime.  The stop signal will send in function
kunit_try_catch_run, and test_gfpzero will handle it.

Link: https://lkml.kernel.org/r/20220309083753.1561921-1-liupeng256@huawei.com
Link: https://lkml.kernel.org/r/20220309083753.1561921-2-liupeng256@huawei.com
Signed-off-by: Peng Liu <liupeng256@huawei.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Wang Kefeng <wangkefeng.wang@huawei.com>
Cc: Daniel Latypov <dlatypov@google.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Tianchen Ding
b33f778bba kfence: alloc kfence_pool after system startup
Allow enabling KFENCE after system startup by allocating its pool via the
page allocator. This provides the flexibility to enable KFENCE even if it
wasn't enabled at boot time.

Link: https://lkml.kernel.org/r/20220307074516.6920-3-dtcccc@linux.alibaba.com
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Peng Liu <liupeng256@huawei.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Tianchen Ding
698361bca2 kfence: allow re-enabling KFENCE after system startup
Patch series "provide the flexibility to enable KFENCE", v3.

If CONFIG_CONTIG_ALLOC is not supported, we fallback to try
alloc_pages_exact().  Allocating pages in this way has limits about
MAX_ORDER (default 11).  So we will not support allocating kfence pool
after system startup with a large KFENCE_NUM_OBJECTS.

When handling failures in kfence_init_pool_late(), we pair
free_pages_exact() to alloc_pages_exact() for compatibility consideration,
though it actually does the same as free_contig_range().

This patch (of 2):

If once KFENCE is disabled by:
echo 0 > /sys/module/kfence/parameters/sample_interval
KFENCE could never be re-enabled until next rebooting.

Allow re-enabling it by writing a positive num to sample_interval.

Link: https://lkml.kernel.org/r/20220307074516.6920-1-dtcccc@linux.alibaba.com
Link: https://lkml.kernel.org/r/20220307074516.6920-2-dtcccc@linux.alibaba.com
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
tangmeng
56eb8e9416 mm/kfence: remove unnecessary CONFIG_KFENCE option
In mm/Makefile has:

  obj-$(CONFIG_KFENCE) += kfence/

So that we don't need 'obj-$(CONFIG_KFENCE) :=' in mm/kfence/Makefile,
delete it from mm/kfence/Makefile.

Link: https://lkml.kernel.org/r/20220221065525.21344-1-tangmeng@uniontech.com
Signed-off-by: tangmeng <tangmeng@uniontech.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Dr. David Alan Gilbert
597da28e1a mm/page_table_check.c: use strtobool for param parsing
Use strtobool rather than open coding "on" and "off" parsing.

Link: https://lkml.kernel.org/r/20220227181038.126926-1-linux@treblig.org
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Miaohe Lin
7a3f2263d7 mm/highmem: remove unnecessary done label
Remove unnecessary done label to simplify the code.

Link: https://lkml.kernel.org/r/20220126092542.64659-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Vlastimil Babka
be4893d92b mm/early_ioremap: declare early_memremap_pgprot_adjust()
The mm/ directory can almost fully be built with W=1, which would help
in local development.  One remaining issue is missing prototype for
early_memremap_pgprot_adjust().

Thus add a declaration for this function.  Use mm/internal.h instead of
asm/early_ioremap.h to avoid missing type definitions and unnecessary
exposure.

Link: https://lkml.kernel.org/r/20220314165724.16071-2-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Randy Dunlap
05fe3c103f mm/usercopy: return 1 from hardened_usercopy __setup() handler
__setup() handlers should return 1 if the command line option is handled
and 0 if not (or maybe never return 0; it just pollutes init's
environment).  This prevents:

  Unknown kernel command line parameters \
  "BOOT_IMAGE=/boot/bzImage-517rc5 hardened_usercopy=off", will be \
  passed to user space.

  Run /sbin/init as init process
   with arguments:
     /sbin/init
   with environment:
     HOME=/
     TERM=linux
     BOOT_IMAGE=/boot/bzImage-517rc5
     hardened_usercopy=off
or
     hardened_usercopy=on
but when "hardened_usercopy=foo" is used, there is no Unknown kernel
command line parameter.

Return 1 to indicate that the boot option has been handled.
Print a warning if strtobool() returns an error on the option string,
but do not mark this as in unknown command line option and do not cause
init's environment to be polluted with this string.

Link: https://lkml.kernel.org/r/20220222034249.14795-1-rdunlap@infradead.org
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Fixes: b5cb15d937 ("usercopy: Allow boot cmdline disabling of hardening")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Acked-by: Chris von Recklinghausen <crecklin@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Christophe Leroy
ad7489d526 mm: uninline copy_overflow()
While building a small config with CONFIG_CC_OPTIMISE_FOR_SIZE, I ended
up with more than 50 times the following function in vmlinux because GCC
doesn't honor the 'inline' keyword:

	c00243bc <copy_overflow>:
	c00243bc:	94 21 ff f0 	stwu    r1,-16(r1)
	c00243c0:	7c 85 23 78 	mr      r5,r4
	c00243c4:	7c 64 1b 78 	mr      r4,r3
	c00243c8:	3c 60 c0 62 	lis     r3,-16286
	c00243cc:	7c 08 02 a6 	mflr    r0
	c00243d0:	38 63 5e e5 	addi    r3,r3,24293
	c00243d4:	90 01 00 14 	stw     r0,20(r1)
	c00243d8:	4b ff 82 45 	bl      c001c61c <__warn_printk>
	c00243dc:	0f e0 00 00 	twui    r0,0
	c00243e0:	80 01 00 14 	lwz     r0,20(r1)
	c00243e4:	38 21 00 10 	addi    r1,r1,16
	c00243e8:	7c 08 03 a6 	mtlr    r0
	c00243ec:	4e 80 00 20 	blr

With -Winline, GCC tells:

	/include/linux/thread_info.h:212:20: warning: inlining failed in call to 'copy_overflow': call is unlikely and code size would grow [-Winline]

copy_overflow() is a non conditional warning called by check_copy_size()
on an error path.

check_copy_size() have to remain inlined in order to benefit from
constant folding, but copy_overflow() is not worth inlining.

Uninline the warning when CONFIG_BUG is selected.

When CONFIG_BUG is not selected, WARN() does nothing so skip it.

This reduces the size of vmlinux by almost 4kbytes.

Link: https://lkml.kernel.org/r/e1723b9cfa924bcefcd41f69d0025b38e4c9364e.1644819985.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Christophe Leroy
6eada26ffc mm: remove usercopy_warn()
Users of usercopy_warn() were removed by commit 53944f171a ("mm:
remove HARDENED_USERCOPY_FALLBACK")

Remove it.

Link: https://lkml.kernel.org/r/5f26643fc70b05f8455b60b99c30c17d635fa640.1644231910.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Stephen Kitt <steve@sk2.org>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Maciej S. Szmigiero
cb325ddde5 mm/zswap.c: allow handling just same-value filled pages
Zswap has an ability to efficiently store same-value filled pages, which
can be turned on and off using the "same_filled_pages_enabled"
parameter.

However, there is currently no way to enable just this (lightweight)
functionality, while not making use of the whole compressed page storage
machinery.

Add a "non_same_filled_pages_enabled" parameter which allows disabling
handling of pages that aren't same-value filled.  This way zswap can be
run in such lightweight same-value filled pages only mode.

Link: https://lkml.kernel.org/r/7dbafa963e8bab43608189abbe2067f4b9287831.1641247624.git.maciej.szmigiero@oracle.com
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
Hugh Dickins
bd55b0c2d6 mm/thp: ClearPageDoubleMap in first page_add_file_rmap()
PageDoubleMap is maintained differently for anon and for shmem+file: the
shmem+file one was never cleared, because a safe place to do so could
not be found; so it would blight future use of the cached hugepage until
evicted.

See https://lore.kernel.org/lkml/1571938066-29031-1-git-send-email-yang.shi@linux.alibaba.com/

But page_add_file_rmap() does provide a safe place to do so (though later
than one might wish): allowing testing to return to an initial state
without a damaging drop_caches.

Link: https://lkml.kernel.org/r/61c5cf99-a962-9a25-597a-53ab1bd8fbc0@google.com
Fixes: 9a73f61bdb ("thp, mlock: do not mlock PTE-mapped file huge pages")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: "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>
2022-03-22 15:57:11 -07:00
Oscar Salvador
734c15700c mm: only re-generate demotion targets when a numa node changes its N_CPU state
Abhishek reported that after patch [1], hotplug operations are taking
roughly double the expected time.  [2]

The reason behind is that the CPU callbacks that
migrate_on_reclaim_init() sets always call set_migration_target_nodes()
whenever a CPU is brought up/down.

But we only care about numa nodes going from having cpus to become
cpuless, and vice versa, as that influences the demotion_target order.

We do already have two CPU callbacks (vmstat_cpu_online() and
vmstat_cpu_dead()) that check exactly that, so get rid of the CPU
callbacks in migrate_on_reclaim_init() and only call
set_migration_target_nodes() from vmstat_cpu_{dead,online}() whenever a
numa node change its N_CPU state.

[1] https://lore.kernel.org/linux-mm/20210721063926.3024591-2-ying.huang@intel.com/
[2] https://lore.kernel.org/linux-mm/eb438ddd-2919-73d4-bd9f-b7eecdd9577a@linux.vnet.ibm.com/

[osalvador@suse.de: add feedback from Huang Ying]
  Link: https://lkml.kernel.org/r/20220314150945.12694-1-osalvador@suse.de

Link: https://lkml.kernel.org/r/20220310120749.23077-1-osalvador@suse.de
Fixes: 884a6e5d1f ("mm/migrate: update node demotion order on hotplug events")
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reported-by: Abhishek Goel <huntbag@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Abhishek Goel <huntbag@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:11 -07:00
David Hildenbrand
395f6081ba drivers/base/memory: determine and store zone for single-zone memory blocks
test_pages_in_a_zone() is just another nasty PFN walker that can easily
stumble over ZONE_DEVICE memory ranges falling into the same memory block
as ordinary system RAM: the memmap of parts of these ranges might possibly
be uninitialized.  In fact, we observed (on an older kernel) with UBSAN:

  UBSAN: Undefined behaviour in ./include/linux/mm.h:1133:50
  index 7 is out of range for type 'zone [5]'
  CPU: 121 PID: 35603 Comm: read_all Kdump: loaded Tainted: [...]
  Hardware name: Dell Inc. PowerEdge R7425/08V001, BIOS 1.12.2 11/15/2019
  Call Trace:
   dump_stack+0x9a/0xf0
   ubsan_epilogue+0x9/0x7a
   __ubsan_handle_out_of_bounds+0x13a/0x181
   test_pages_in_a_zone+0x3c4/0x500
   show_valid_zones+0x1fa/0x380
   dev_attr_show+0x43/0xb0
   sysfs_kf_seq_show+0x1c5/0x440
   seq_read+0x49d/0x1190
   vfs_read+0xff/0x300
   ksys_read+0xb8/0x170
   do_syscall_64+0xa5/0x4b0
   entry_SYSCALL_64_after_hwframe+0x6a/0xdf
  RIP: 0033:0x7f01f4439b52

We seem to stumble over a memmap that contains a garbage zone id.  While
we could try inserting pfn_to_online_page() calls, it will just make
memory offlining slower, because we use test_pages_in_a_zone() to make
sure we're offlining pages that all belong to the same zone.

Let's just get rid of this PFN walker and determine the single zone of a
memory block -- if any -- for early memory blocks during boot.  For memory
onlining, we know the single zone already.  Let's avoid any additional
memmap scanning and just rely on the zone information available during
boot.

For memory hot(un)plug, we only really care about memory blocks that:
* span a single zone (and, thereby, a single node)
* are completely System RAM (IOW, no holes, no ZONE_DEVICE)
If one of these conditions is not met, we reject memory offlining.
Hotplugged memory blocks (starting out offline), always meet both
conditions.

There are three scenarios to handle:

(1) Memory hot(un)plug

A memory block with zone == NULL cannot be offlined, corresponding to
our previous test_pages_in_a_zone() check.

After successful memory onlining/offlining, we simply set the zone
accordingly.
* Memory onlining: set the zone we just used for onlining
* Memory offlining: set zone = NULL

So a hotplugged memory block starts with zone = NULL. Once memory
onlining is done, we set the proper zone.

(2) Boot memory with !CONFIG_NUMA

We know that there is just a single pgdat, so we simply scan all zones
of that pgdat for an intersection with our memory block PFN range when
adding the memory block. If more than one zone intersects (e.g., DMA and
DMA32 on x86 for the first memory block) we set zone = NULL and
consequently mimic what test_pages_in_a_zone() used to do.

(3) Boot memory with CONFIG_NUMA

At the point in time we create the memory block devices during boot, we
don't know yet which nodes *actually* span a memory block. While we could
scan all zones of all nodes for intersections, overlapping nodes complicate
the situation and scanning all nodes is possibly expensive. But that
problem has already been solved by the code that sets the node of a memory
block and creates the link in the sysfs --
do_register_memory_block_under_node().

So, we hook into the code that sets the node id for a memory block. If
we already have a different node id set for the memory block, we know
that multiple nodes *actually* have PFNs falling into our memory block:
we set zone = NULL and consequently mimic what test_pages_in_a_zone() used
to do. If there is no node id set, we do the same as (2) for the given
node.

Note that the call order in driver_init() is:
-> memory_dev_init(): create memory block devices
-> node_dev_init(): link memory block devices to the node and set the
		    node id

So in summary, we detect if there is a single zone responsible for this
memory block and we consequently store the zone in that case in the
memory block, updating it during memory onlining/offlining.

Link: https://lkml.kernel.org/r/20220210184359.235565-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Rafael Parra <rparrazo@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rafael Parra <rparrazo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
David Hildenbrand
cc6515591b drivers/base/node: rename link_mem_sections() to register_memory_block_under_node()
Patch series "drivers/base/memory: determine and store zone for single-zone memory blocks", v2.

I remember talking to Michal in the past about removing
test_pages_in_a_zone(), which we use for:
* verifying that a memory block we intend to offline is really only managed
  by a single zone. We don't support offlining of memory blocks that are
  managed by multiple zones (e.g., multiple nodes, DMA and DMA32)
* exposing that zone to user space via
  /sys/devices/system/memory/memory*/valid_zones

Now that I identified some more cases where test_pages_in_a_zone() might
go wrong, and we received an UBSAN report (see patch #3), let's get rid of
this PFN walker.

So instead of detecting the zone at runtime with test_pages_in_a_zone() by
scanning the memmap, let's determine and remember for each memory block if
it's managed by a single zone.  The stored zone can then be used for the
above two cases, avoiding a manual lookup using test_pages_in_a_zone().

This avoids eventually stumbling over uninitialized memmaps in corner
cases, especially when ZONE_DEVICE ranges partly fall into memory block
(that are responsible for managing System RAM).

Handling memory onlining is easy, because we online to exactly one zone.
Handling boot memory is more tricky, because we want to avoid scanning all
zones of all nodes to detect possible zones that overlap with the physical
memory region of interest.  Fortunately, we already have code that
determines the applicable nodes for a memory block, to create sysfs links
-- we'll hook into that.

Patch #1 is a simple cleanup I had laying around for a longer time.
Patch #2 contains the main logic to remove test_pages_in_a_zone() and
further details.

[1] https://lkml.kernel.org/r/20220128144540.153902-1-david@redhat.com
[2] https://lkml.kernel.org/r/20220203105212.30385-1-david@redhat.com

This patch (of 2):

Let's adjust the stale terminology, making it match
unregister_memory_block_under_nodes() and
do_register_memory_block_under_node().  We're dealing with memory block
devices, which span 1..X memory sections.

Link: https://lkml.kernel.org/r/20220210184359.235565-1-david@redhat.com
Link: https://lkml.kernel.org/r/20220210184359.235565-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Rafael Parra <rparrazo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Miaohe Lin
36ba30bc1d mm/memory_hotplug: fix misplaced comment in offline_pages
It's misplaced since commit 7960509329 ("mm, memory_hotplug: print
reason for the offlining failure").  Move it to the right place.

Link: https://lkml.kernel.org/r/20220207133643.23427-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Miaohe Lin
b27340a5bd mm/memory_hotplug: clean up try_offline_node
We can use helper macro node_spanned_pages to check whether node spans
pages.  And we can change the parameter of check_cpu_on_node to nid as
that's what it really cares.  Thus we can further get rid of the local
variable pgdat and improve the readability a bit.

Link: https://lkml.kernel.org/r/20220207133643.23427-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Miaohe Lin
d6aad2016a mm/memory_hotplug: avoid calling zone_intersects() for ZONE_NORMAL
If zid reaches ZONE_NORMAL, the caller will always get the NORMAL zone no
matter what zone_intersects() returns.  So we can save some possible cpu
cycles by avoid calling zone_intersects() for ZONE_NORMAL.

Link: https://lkml.kernel.org/r/20220207133643.23427-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Miaohe Lin
2b6bf15f46 mm/memory_hotplug: remove obsolete comment of __add_pages
Patch series "A few cleanup patches around memory_hotplug".

This series contains a few patches to fix obsolete and misplaced comments,
clean up the try_offline_node function and so on.

This patch (of 4):

Since commit f1dd2cd13c ("mm, memory_hotplug: do not associate hotadded
memory to zones until online"), there is no need to pass in the zone.

[akpm@linux-foundation.org: remove the comment altogether, per David]

Link: https://lkml.kernel.org/r/20220207133643.23427-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220207133643.23427-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Wei Yang
8c9bb39816 memcg: do not tweak node in alloc_mem_cgroup_per_node_info
alloc_mem_cgroup_per_node_info is allocated for each possible node and
this used to be a problem because !node_online nodes didn't have
appropriate data structure allocated.  This has changed by "mm: handle
uninitialized numa nodes gracefully" so we can drop the special casing
here.

Link: https://lkml.kernel.org/r/20220127085305.20890-7-mhocko@kernel.org
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Alexey Makhalov <amakhalov@vmware.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rafael Aquini <raquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Michal Hocko
7c30daac20 mm: make free_area_init_node aware of memory less nodes
free_area_init_node is also called from memory less node initialization
path (free_area_init_memoryless_node).  It doesn't really make much sense
to display the physical memory range for those nodes: Initmem setup node
XX [mem 0x0000000000000000-0x0000000000000000]

Instead be explicit that the node is memoryless: Initmem setup node XX as
memoryless

Link: https://lkml.kernel.org/r/20220127085305.20890-6-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael Aquini <raquini@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Alexey Makhalov <amakhalov@vmware.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Michal Hocko
70b5b46a75 mm, memory_hotplug: reorganize new pgdat initialization
When a !node_online node is brought up it needs a hotplug specific
initialization because the node could be either uninitialized yet or it
could have been recycled after previous hotremove.  hotadd_init_pgdat is
responsible for that.

Internal pgdat state is initialized at two places currently
	- hotadd_init_pgdat
	- free_area_init_core_hotplug

There is no real clear cut what should go where but this patch's chosen to
move the whole internal state initialization into
free_area_init_core_hotplug.  hotadd_init_pgdat is still responsible to
pull all the parts together - most notably to initialize zonelists because
those depend on the overall topology.

This patch doesn't introduce any functional change.

Link: https://lkml.kernel.org/r/20220127085305.20890-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael Aquini <raquini@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Alexey Makhalov <amakhalov@vmware.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00