Commit Graph

30406 Commits

Author SHA1 Message Date
Yuyang Du 154f185e9c locking/lockdep: Update comments on dependency search
The breadth-first search is implemented as flat-out non-recursive now, but
the comments are still describing it as recursive, update the comments in
that regard.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-16-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:47 +02:00
Yuyang Du 77a806922c locking/lockdep: Avoid constant checks in __bfs by using offset reference
In search of a dependency in the lock graph, there is contant checks for
forward or backward search. Directly reference the field offset of the
struct that differentiates the type of search to avoid those checks.

No functional change.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-15-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:46 +02:00
Yuyang Du c166132559 locking/lockdep: Change the return type of __cq_dequeue()
With the change, we can slightly adjust the code to iterate the queue in BFS
search, which simplifies the code. No functional change.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-14-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:46 +02:00
Yuyang Du aa4807719e locking/lockdep: Change type of the element field in circular_queue
The element field is an array in struct circular_queue to keep track of locks
in the search. Making it the same type as the locks avoids type cast. Also
fix a typo and elaborate the comment above struct circular_queue.

No functional change.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-13-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:45 +02:00
Yuyang Du 31a490e5c5 locking/lockdep: Update comment
A leftover comment is removed. While at it, add more explanatory
comments. Such a trivial patch!

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-12-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:44 +02:00
Yuyang Du 0b9fc8ecfa locking/lockdep: Remove unused argument in validate_chain() and check_deadlock()
The lockdep_map argument in them is not used, remove it.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-11-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:44 +02:00
Yuyang Du 01bb6f0af9 locking/lockdep: Change the range of class_idx in held_lock struct
held_lock->class_idx is used to point to the class of the held lock. The
index is shifted by 1 to make index 0 mean no class, which results in class
index shifting back and forth but is not worth doing so.

The reason is: (1) there will be no "no-class" held_lock to begin with, and
(2) index 0 seems to be used for error checking, but if something wrong
indeed happened, the index can't be counted on to distinguish it as that
something won't set the class_idx to 0 on purpose to tell us it is wrong.

Therefore, change the index to start from 0. This saves a lot of
back-and-forth shifts and a class slot back to lock_classes.

Since index 0 is now used for lock class, we change the initial chain key to
-1 to avoid key collision, which is due to the fact that __jhash_mix(0, 0, 0) = 0.
Actually, the initial chain key can be any arbitrary value other than 0.

In addition, a bitmap is maintained to keep track of the used lock classes,
and we check the validity of the held lock against that bitmap.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-10-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:43 +02:00
Yuyang Du f6ec8829ac locking/lockdep: Define INITIAL_CHAIN_KEY for chain keys to start with
Chain keys are computed using Jenkins hash function, which needs an initial
hash to start with. Dedicate a macro to make this clear and configurable. A
later patch changes this initial chain key.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-9-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:43 +02:00
Yuyang Du e196e479a3 locking/lockdep: Use lockdep_init_task for task initiation consistently
Despite that there is a lockdep_init_task() which does nothing, lockdep
initiates tasks by assigning lockdep fields and does so inconsistently. Fix
this by using lockdep_init_task().

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-8-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:42 +02:00
Yuyang Du 834494b280 locking/lockdep: Print the right depth for chain key collision
Since chains are separated by IRQ context, so when printing a chain the
depth should be consistent with it.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-6-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:36 +02:00
Yuyang Du e7a38f63ba locking/lockdep: Remove useless conditional macro
Since #defined(CONFIG_PROVE_LOCKING) is used in the scope of #ifdef
CONFIG_PROVE_LOCKING, it can be removed.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-5-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:35 +02:00
Yuyang Du c52478f4f3 locking/lockdep: Adjust lock usage bit character checks
The lock usage bit characters are defined and determined with tricks.
Add some explanation to make it a bit clearer, then adjust the logic to
check the usage, which optimizes the code a bit.

No functional change.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-4-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:35 +02:00
Yuyang Du f7c1c6b36a locking/lockdep: Change all print_*() return type to void
Since none of the print_*() function's return value is necessary, change
their return type to void. No functional change.

In cases where an invariable return value is used, this change slightly
improves readability, i.e.:

	print_x();
	return 0;

is definitely better than:

	return print_x(); /* where print_x() always returns 0 */

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bvanassche@acm.org
Cc: frederic@kernel.org
Cc: ming.lei@redhat.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190506081939.74287-2-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:55:32 +02:00
Ingo Molnar 26b73da360 Linux 5.2-rc3
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Merge tag 'v5.2-rc3' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:50:18 +02:00
Linus Torvalds 6751b8d91a Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "On the kernel side there's a bunch of ring-buffer ordering fixes for a
  reproducible bug, plus a PEBS constraints regression fix.

  Plus tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools headers UAPI: Sync kvm.h headers with the kernel sources
  perf record: Fix s390 missing module symbol and warning for non-root users
  perf machine: Read also the end of the kernel
  perf test vmlinux-kallsyms: Ignore aliases to _etext when searching on kallsyms
  perf session: Add missing swap ops for namespace events
  perf namespace: Protect reading thread's namespace
  tools headers UAPI: Sync drm/drm.h with the kernel
  tools headers UAPI: Sync drm/i915_drm.h with the kernel
  tools headers UAPI: Sync linux/fs.h with the kernel
  tools headers UAPI: Sync linux/sched.h with the kernel
  tools arch x86: Sync asm/cpufeatures.h with the with the kernel
  tools include UAPI: Update copy of files related to new fspick, fsmount, fsconfig, fsopen, move_mount and open_tree syscalls
  perf arm64: Fix mksyscalltbl when system kernel headers are ahead of the kernel
  perf data: Fix 'strncat may truncate' build failure with recent gcc
  perf/ring-buffer: Use regular variables for nesting
  perf/ring-buffer: Always use {READ,WRITE}_ONCE() for rb->user_page data
  perf/ring_buffer: Add ordering to rb->nest increment
  perf/ring_buffer: Fix exposing a temporarily decreased data_head
  perf/x86/intel/ds: Fix EVENT vs. UEVENT PEBS constraints
2019-06-02 11:08:12 -07:00
Linus Torvalds 4fb5741c7c Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull stacktrace fix from Ingo Molnar:
 "Fix a stack_trace_save_tsk_reliable() regression"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stacktrace: Unbreak stack_trace_save_tsk_reliable()
2019-06-02 11:04:42 -07:00
Linus Torvalds 7b3064f0e8 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "Various fixes and followups"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, compaction: make sure we isolate a valid PFN
  include/linux/generic-radix-tree.h: fix kerneldoc comment
  kernel/signal.c: trace_signal_deliver when signal_group_exit
  drivers/iommu/intel-iommu.c: fix variable 'iommu' set but not used
  spdxcheck.py: fix directory structures
  kasan: initialize tag to 0xff in __kasan_kmalloc
  z3fold: fix sheduling while atomic
  scripts/gdb: fix invocation when CONFIG_COMMON_CLK is not set
  mm/gup: continue VM_FAULT_RETRY processing even for pre-faults
  ocfs2: fix error path kobject memory leak
  memcg: make it work on sparse non-0-node systems
  mm, memcg: consider subtrees in memory.events
  prctl_set_mm: downgrade mmap_sem to read lock
  prctl_set_mm: refactor checks from validate_prctl_map
  kernel/fork.c: make max_threads symbol static
  arch/arm/boot/compressed/decompress.c: fix build error due to lz4 changes
  arch/parisc/configs/c8000_defconfig: remove obsoleted CONFIG_DEBUG_SLAB_LEAK
  mm/vmalloc.c: fix typo in comment
  lib/sort.c: fix kernel-doc notation warnings
  mm: fix Documentation/vm/hmm.rst Sphinx warnings
2019-06-02 08:51:30 -07:00
Zhenliang Wei 98af37d624 kernel/signal.c: trace_signal_deliver when signal_group_exit
In the fixes commit, removing SIGKILL from each thread signal mask and
executing "goto fatal" directly will skip the call to
"trace_signal_deliver".  At this point, the delivery tracking of the
SIGKILL signal will be inaccurate.

Therefore, we need to add trace_signal_deliver before "goto fatal" after
executing sigdelset.

Note: SEND_SIG_NOINFO matches the fact that SIGKILL doesn't have any info.

Link: http://lkml.kernel.org/r/20190425025812.91424-1-weizhenliang@huawei.com
Fixes: cf43a757fd ("signal: Restore the stop PTRACE_EVENT_EXIT")
Signed-off-by: Zhenliang Wei <weizhenliang@huawei.com>
Reviewed-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ivan Delalande <colona@arista.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:32 -07:00
Chris Down 9852ae3fe5 mm, memcg: consider subtrees in memory.events
memory.stat and other files already consider subtrees in their output, and
we should too in order to not present an inconsistent interface.

The current situation is fairly confusing, because people interacting with
cgroups expect hierarchical behaviour in the vein of memory.stat,
cgroup.events, and other files.  For example, this causes confusion when
debugging reclaim events under low, as currently these always read "0" at
non-leaf memcg nodes, which frequently causes people to misdiagnose breach
behaviour.  The same confusion applies to other counters in this file when
debugging issues.

Aggregation is done at write time instead of at read-time since these
counters aren't hot (unlike memory.stat which is per-page, so it does it
at read time), and it makes sense to bundle this with the file
notifications.

After this patch, events are propagated up the hierarchy:

    [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events
    low 0
    high 0
    max 0
    oom 0
    oom_kill 0
    [root@ktst ~]# systemd-run -p MemoryMax=1 true
    Running as unit: run-r251162a189fb4562b9dabfdc9b0422f5.service
    [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events
    low 0
    high 0
    max 7
    oom 1
    oom_kill 1

As this is a change in behaviour, this can be reverted to the old
behaviour by mounting with the `memory_localevents' flag set.  However, we
use the new behaviour by default as there's a lack of evidence that there
are any current users of memory.events that would find this change
undesirable.

akpm: this is a behaviour change, so Cc:stable.  THis is so that
forthcoming distros which use cgroup v2 are more likely to pick up the
revised behaviour.

Link: http://lkml.kernel.org/r/20190208224419.GA24772@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Michal Koutný bc81426f5b prctl_set_mm: downgrade mmap_sem to read lock
The commit a3b609ef9f ("proc read mm's {arg,env}_{start,end} with mmap
semaphore taken.") added synchronization of reading argument/environment
boundaries under mmap_sem.  Later commit 88aa7cc688 ("mm: introduce
arg_lock to protect arg_start|end and env_start|end in mm_struct") avoided
the coarse use of mmap_sem in similar situations.  But there still
remained two places that (mis)use mmap_sem.

get_cmdline should also use arg_lock instead of mmap_sem when it reads the
boundaries.

The second place that should use arg_lock is in prctl_set_mm.  By
protecting the boundaries fields with the arg_lock, we can downgrade
mmap_sem to reader lock (analogous to what we already do in
prctl_set_mm_map).

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/20190502125203.24014-3-mkoutny@suse.com
Fixes: 88aa7cc688 ("mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Co-developed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Michal Koutný 11bbd8b416 prctl_set_mm: refactor checks from validate_prctl_map
Despite comment of validate_prctl_map claims there are no capability
checks, it is not completely true since commit 4d28df6152 ("prctl: Allow
local CAP_SYS_ADMIN changing exe_file").  Extract the check out of the
function and make the function perform purely arithmetic checks.

This patch should not change any behavior, it is mere refactoring for
following patch.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/20190502125203.24014-2-mkoutny@suse.com
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Kefeng Wang 8856ae4df3 kernel/fork.c: make max_threads symbol static
Fix build warning,
kernel/fork.c:125:5: warning: symbol 'max_threads' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20190516015118.140561-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Linus Torvalds 702c31e856 Power management fixes for 5.2-rc3
- Modify the PCI bus type's PM code to avoid putting devices left
    by their drivers in D0 on purpose during suspend to idle into
    low-power states as doing that may confuse the system resume
    callbacks of the drivers in question (Rafael Wysocki).
 
  - Avoid checking ACPI wakeup configuration during system-wide
    suspend for suspended devices that do not use ACPI-based wakeup
    to allow them to stay in suspend more often (Rafael Wysocki).
 
  - The last phase of hibernation is analogous to system-wide suspend
    also because on platforms with ACPI it passes control to the
    platform firmware to complete the transision, so make it indicate
    that by calling pm_set_suspend_via_firmware() to allow the drivers
    that care about this to do the right thing (Rafael Wysocki).
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Merge tag 'pm-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix three issues in the system-wide suspend and hibernation area
  related to PCI device PM handling by suspend-to-idle, device wakeup
  optimizations and arbitrary differences between suspend and
  hiberantion.

  Specifics:

   - Modify the PCI bus type's PM code to avoid putting devices left by
     their drivers in D0 on purpose during suspend to idle into
     low-power states as doing that may confuse the system resume
     callbacks of the drivers in question (Rafael Wysocki).

   - Avoid checking ACPI wakeup configuration during system-wide suspend
     for suspended devices that do not use ACPI-based wakeup to allow
     them to stay in suspend more often (Rafael Wysocki).

   - The last phase of hibernation is analogous to system-wide suspend
     also because on platforms with ACPI it passes control to the
     platform firmware to complete the transision, so make it indicate
     that by calling pm_set_suspend_via_firmware() to allow the drivers
     that care about this to do the right thing (Rafael Wysocki)"

* tag 'pm-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PCI: PM: Avoid possible suspend-to-idle issue
  ACPI: PM: Call pm_set_suspend_via_firmware() during hibernation
  ACPI/PCI: PM: Add missing wakeup.flags.valid checks
2019-05-31 10:38:35 -07:00
Linus Torvalds 2f4c533499 SPDX update for 5.2-rc3, round 1
Here is another set of reviewed patches that adds SPDX tags to different
 kernel files, based on a set of rules that are being used to parse the
 comments to try to determine that the license of the file is
 "GPL-2.0-or-later" or "GPL-2.0-only".  Only the "obvious" versions of
 these matches are included here, a number of "non-obvious" variants of
 text have been found but those have been postponed for later review and
 analysis.
 
 There is also a patch in here to add the proper SPDX header to a bunch
 of Kbuild files that we have missed in the past due to new files being
 added and forgetting that Kbuild uses two different file names for
 Makefiles.  This issue was reported by the Kbuild maintainer.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull yet more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of
  these matches are included here, a number of "non-obvious" variants of
  text have been found but those have been postponed for later review
  and analysis.

  There is also a patch in here to add the proper SPDX header to a bunch
  of Kbuild files that we have missed in the past due to new files being
  added and forgetting that Kbuild uses two different file names for
  Makefiles. This issue was reported by the Kbuild maintainer.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits)
  treewide: Add SPDX license identifier - Kbuild
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
  ...
2019-05-31 08:34:32 -07:00
Thomas Gleixner 25763b3c86 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of version 2 of the gnu general public license as
  published by the free software foundation

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 107 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:53 -07:00
Thomas Gleixner 468e15fdc2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 170
Based on 1 normalized pattern(s):

  this file is release under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 1 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.216732358@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:39 -07:00
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Linus Torvalds 9e82b4a91d This fixes a memory leak from the error path in the event filter logic.
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Merge tag 'trace-v5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "This fixes a memory leak from the error path in the event filter
  logic"

* tag 'trace-v5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Avoid memory leak in predicate_parse()
2019-05-29 11:26:40 -07:00
Ingo Molnar 849e96f300 perf/urgent fixes:
BPF:
 
   Jiri Olsa:
 
   - Fixup determination of end of kernel map, to avoid having BPF programs,
     that are after the kernel headers and just before module texts mixed up in
     the kernel map.
 
 tools UAPI header copies:
 
   Arnaldo Carvalho de Melo:
 
   - Update copy of files related to new fspick, fsmount, fsconfig, fsopen,
     move_mount and open_tree syscalls.
 
   - Sync cpufeatures.h, sched.h, fs.h, drm.h, i915_drm.h and kvm.h headers.
 
 Namespaces:
 
   Namhyung Kim:
 
   - Add missing byte swap ops for namespace events when processing records from
     perf.data files that could have been recorded in a arch with a different
     endianness.
 
   - Fix access to the thread namespaces list by using the namespaces_lock.
 
 perf data:
 
   Shawn Landden:
 
   - Fix 'strncat may truncate' build failure with recent gcc.
 
 s/390
 
   Thomas Richter:
 
   - Fix s390 missing module symbol and warning for non-root users in 'perf record'.
 
 arm64:
 
   Vitaly Chikunov:
 
   - Fix mksyscalltbl when system kernel headers are ahead of the kernel.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-5.2-20190528' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes:

BPF:

  Jiri Olsa:

  - Fixup determination of end of kernel map, to avoid having BPF programs,
    that are after the kernel headers and just before module texts mixed up in
    the kernel map.

tools UAPI header copies:

  Arnaldo Carvalho de Melo:

  - Update copy of files related to new fspick, fsmount, fsconfig, fsopen,
    move_mount and open_tree syscalls.

  - Sync cpufeatures.h, sched.h, fs.h, drm.h, i915_drm.h and kvm.h headers.

Namespaces:

  Namhyung Kim:

  - Add missing byte swap ops for namespace events when processing records from
    perf.data files that could have been recorded in a arch with a different
    endianness.

  - Fix access to the thread namespaces list by using the namespaces_lock.

perf data:

  Shawn Landden:

  - Fix 'strncat may truncate' build failure with recent gcc.

s/390

  Thomas Richter:

  - Fix s390 missing module symbol and warning for non-root users in 'perf record'.

arm64:

  Vitaly Chikunov:

  - Fix mksyscalltbl when system kernel headers are ahead of the kernel.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-28 23:16:22 +02:00
Tomas Bortoli dfb4a6f219 tracing: Avoid memory leak in predicate_parse()
In case of errors, predicate_parse() goes to the out_free label
to free memory and to return an error code.

However, predicate_parse() does not free the predicates of the
temporary prog_stack array, thence leaking them.

Link: http://lkml.kernel.org/r/20190528154338.29976-1-tomasbortoli@gmail.com

Cc: stable@vger.kernel.org
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: syzbot+6b8e0fb820e570c59e19@syzkaller.appspotmail.com
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
[ Added protection around freeing prog_stack[i].pred ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-28 16:27:58 -04:00
Waiman Long 5ca584d935 futex: Consolidate duplicated timer setup code
Add a new futex_setup_timer() helper function to consolidate all the
hrtimer_sleeper setup code.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lkml.kernel.org/r/20190528160345.24017-1-longman@redhat.com
2019-05-28 11:12:00 -07:00
Rafael J. Wysocki bb1869012d ACPI: PM: Call pm_set_suspend_via_firmware() during hibernation
On systems with ACPI platform firmware the last stage of hibernation
is analogous to system suspend to S3 (suspend-to-RAM), so it should
be handled analogously.  In particular, pm_suspend_via_firmware()
should return 'true' in that stage to let the callers of it know that
control will be passed to the platform firmware going forward, so
pm_set_suspend_via_firmware() needs to be called then in analogy with
acpi_suspend_begin().

However, the platform hibernation ->begin() callback is invoked
during the "freeze" transition (before creating a snapshot image of
system memory) as well as during the "hibernate" transition which is
the last stage of it and pm_set_suspend_via_firmware() should be
invoked by that callback in the latter stage only.

In order to implement that redefine the hibernation ->begin()
callback to take a pm_message_t argument to indicate which stage
of hibernation is taking place and rework acpi_hibernation_begin()
and acpi_hibernation_begin_old() to take it into account as needed.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-05-27 10:51:45 +02:00
Linus Torvalds c5b440951a Make the GCC 9 warning for sub struct memset go away.
GCC 9 now warns about calling memset() on partial structures when it
 goes across multiple fields. This adds a helper for the place in
 tracing that does this type of clearing of a structure.
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Merge tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing warning fix from Steven Rostedt:
 "Make the GCC 9 warning for sub struct memset go away.

  GCC 9 now warns about calling memset() on partial structures when it
  goes across multiple fields. This adds a helper for the place in
  tracing that does this type of clearing of a structure"

* tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Silence GCC 9 array bounds warning
2019-05-26 13:49:40 -07:00
Miguel Ojeda 0c97bf863e tracing: Silence GCC 9 array bounds warning
Starting with GCC 9, -Warray-bounds detects cases when memset is called
starting on a member of a struct but the size to be cleared ends up
writing over further members.

Such a call happens in the trace code to clear, at once, all members
after and including `seq` on struct trace_iterator:

    In function 'memset',
        inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3:
    ./include/linux/string.h:344:9: warning: '__builtin_memset' offset
    [8505, 8560] from the object at 'iter' is out of the bounds of
    referenced subobject 'seq' with type 'struct trace_seq' at offset
    4368 [-Warray-bounds]
      344 |  return __builtin_memset(p, c, size);
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

In order to avoid GCC complaining about it, we compute the address
ourselves by adding the offsetof distance instead of referring
directly to the member.

Since there are two places doing this clear (trace.c and trace_kdb.c),
take the chance to move the workaround into a single place in
the internal header.

Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.com

Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[ Removed unnecessary parenthesis around "iter" ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-25 23:04:30 -04:00
Linus Torvalds a2c48d98fc Tom Zanussi sent me some small fixes and cleanups to the histogram
code and I forgot to incorporate them.
 
 I also added a small clean up patch that was sent to me a while ago
 and I just noticed it.
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Merge tag 'trace-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Tom Zanussi sent me some small fixes and cleanups to the histogram
  code and I forgot to incorporate them.

  I also added a small clean up patch that was sent to me a while ago
  and I just noticed it"

* tag 'trace-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  kernel/trace/trace.h: Remove duplicate header of trace_seq.h
  tracing: Add a check_val() check before updating cond_snapshot() track_val
  tracing: Check keys for variable references in expressions too
  tracing: Prevent hist_field_var_ref() from accessing NULL tracing_map_elts
2019-05-25 10:08:14 -07:00
Linus Torvalds 86c2f5d653 SPDX update for 5.2-rc2, round 2
Here is another set of reviewed patches that adds SPDX tags to different
 kernel files, based on a set of rules that are being used to parse the
 comments to try to determine that the license of the file is
 "GPL-2.0-or-later".  Only the "obvious" versions of these matches are
 included here, a number of "non-obvious" variants of text have been
 found but those have been postponed for later review and analysis.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pule more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later".

  Only the "obvious" versions of these matches are included here, a
  number of "non-obvious" variants of text have been found but those
  have been postponed for later review and analysis.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (85 commits)
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 125
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 123
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 122
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 121
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 120
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 119
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 116
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 114
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 113
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 112
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 111
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 110
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 106
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 105
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 103
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 101
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 98
  ...
2019-05-24 14:31:58 -07:00
Waiman Long 51816e9e11 locking/lock_events: Use this_cpu_add() when necessary
The kernel test robot has reported that the use of __this_cpu_add()
causes bug messages like:

  BUG: using __this_cpu_add() in preemptible [00000000] code: ...

Given the imprecise nature of the count and the possibility of resetting
the count and doing the measurement again, this is not really a big
problem to use the unprotected __this_cpu_*() functions.

To make the preemption checking code happy, the this_cpu_*() functions
will be used if CONFIG_DEBUG_PREEMPT is defined.

The imprecise nature of the locking counts are also documented with
the suggestion that we should run the measurement a few times with the
counts reset in between to get a better picture of what is going on
under the hood.

Fixes: a8654596f0 ("locking/rwsem: Enable lock event counting")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-24 14:17:18 -07:00
Thomas Gleixner 6ff3f917e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 38
Based on 1 normalized pattern(s):

  this file is released under the gplv2 and any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.732920462@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00
Thomas Gleixner b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public licence as published by
  the free software foundation either version 2 of the licence or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00
Anders Roxell c0090c4c85 locking/lockdep: Remove the unused print_lock_trace() function
gcc warns that function print_lock_trace() is unused if
CONFIG_PROVE_LOCKING isn't set:

../kernel/locking/lockdep.c:2820:13: warning: ‘print_lock_trace’ defined but not used [-Wunused-function]

Rework so we remove the function if CONFIG_PROVE_LOCKING isn't set.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: will.deacon@arm.com
Fixes: c120bce780 ("lockdep: Simplify stack trace handling")
Link: http://lkml.kernel.org/r/20190516191326.27003-1-anders.roxell@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 09:05:46 +02:00
Peter Zijlstra 5322ea58a0 perf/ring-buffer: Use regular variables for nesting
While the IRQ/NMI will nest, the nest-count will be invariant over the
actual exception, since it will decrement equal to increment.

This means we can -- carefully -- use a regular variable since the
typical LOAD-STORE race doesn't exist (similar to preempt_count).

This optimizes the ring-buffer for all LOAD-STORE architectures, since
they need to use atomic ops to implement local_t.

Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Cc: yabinc@google.com
Link: http://lkml.kernel.org/r/20190517115418.481392777@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 09:00:11 +02:00
Peter Zijlstra 4d839dd9e4 perf/ring-buffer: Always use {READ,WRITE}_ONCE() for rb->user_page data
We must use {READ,WRITE}_ONCE() on rb->user_page data such that
concurrent usage will see whole values. A few key sites were missing
this.

Suggested-by: Yabin Cui <yabinc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Fixes: 7b732a7504 ("perf_counter: new output ABI - part 1")
Link: http://lkml.kernel.org/r/20190517115418.394192145@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 09:00:11 +02:00
Peter Zijlstra 3f9fbe9bd8 perf/ring_buffer: Add ordering to rb->nest increment
Similar to how decrementing rb->next too early can cause data_head to
(temporarily) be observed to go backward, so too can this happen when
we increment too late.

This barrier() ensures the rb->head load happens after the increment,
both the one in the 'goto again' path, as the one from
perf_output_get_handle() -- albeit very unlikely to matter for the
latter.

Suggested-by: Yabin Cui <yabinc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Fixes: ef60777c9a ("perf: Optimize the perf_output() path by removing IRQ-disables")
Link: http://lkml.kernel.org/r/20190517115418.309516009@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 09:00:10 +02:00
Yabin Cui 1b038c6e05 perf/ring_buffer: Fix exposing a temporarily decreased data_head
In perf_output_put_handle(), an IRQ/NMI can happen in below location and
write records to the same ring buffer:

	...
	local_dec_and_test(&rb->nest)
	...                          <-- an IRQ/NMI can happen here
	rb->user_page->data_head = head;
	...

In this case, a value A is written to data_head in the IRQ, then a value
B is written to data_head after the IRQ. And A > B. As a result,
data_head is temporarily decreased from A to B. And a reader may see
data_head < data_tail if it read the buffer frequently enough, which
creates unexpected behaviors.

This can be fixed by moving dec(&rb->nest) to after updating data_head,
which prevents the IRQ/NMI above from updating data_head.

[ Split up by peterz. ]

Signed-off-by: Yabin Cui <yabinc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: mark.rutland@arm.com
Fixes: ef60777c9a ("perf: Optimize the perf_output() path by removing IRQ-disables")
Link: http://lkml.kernel.org/r/20190517115418.224478157@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 09:00:10 +02:00
Sebastian Andrzej Siewior 978315462d locking/lockdep: Don't complain about incorrect name for no validate class
It is possible to ignore the validation for a certain lock by using:

	lockdep_set_novalidate_class()

on it. Each invocation will assign a new name to the class it created
for created __lockdep_no_validate__. That means that once
lockdep_set_novalidate_class() has been used on two locks then
class->name won't match lock->name for the first lock triggering the
warning.

So ignore changed non-matching ->name pointer for the special
__lockdep_no_validate__ class.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20190517212234.32611-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 08:41:59 +02:00
Jagadeesh Pagadala 4eebe38a37 kernel/trace/trace.h: Remove duplicate header of trace_seq.h
Remove duplicate header which is included twice.

Link: http://lkml.kernel.org/r/1553725186-41442-1-git-send-email-jagdsh.linux@gmail.com

Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Jagadeesh Pagadala <jagdsh.linux@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-22 15:37:41 -04:00
Linus Torvalds 2c1212de6f SPDX update for 5.2-rc2, round 1
Here are series of patches that add SPDX tags to different kernel files,
 based on two different things:
   - SPDX entries are added to a bunch of files that we missed a year ago
     that do not have any license information at all.
 
     These were either missed because the tool saw the MODULE_LICENSE()
     tag, or some EXPORT_SYMBOL tags, and got confused and thought the
     file had a real license, or the files have been added since the last
     big sweep, or they were Makefile/Kconfig files, which we didn't
     touch last time.
 
   - Add GPL-2.0-only or GPL-2.0-or-later tags to files where our scan
     tools can determine the license text in the file itself.  Where this
     happens, the license text is removed, in order to cut down on the
     700+ different ways we have in the kernel today, in a quest to get
     rid of all of these.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 The reason for these "large" patches is if we were to continue to
 progress at the current rate of change in the kernel, adding license
 tags to individual files in different subsystems, we would be finished
 in about 10 years at the earliest.
 
 There will be more series of these types of patches coming over the next
 few weeks as the tools and reviewers crunch through the more "odd"
 variants of how to say "GPLv2" that developers have come up with over
 the years, combined with other fun oddities (GPL + a BSD disclaimer?)
 that are being unearthed, with the goal for the whole kernel to be
 cleaned up.
 
 These diffstats are not small, 3840 files are touched, over 10k lines
 removed in just 24 patches.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull SPDX update from Greg KH:
 "Here is a series of patches that add SPDX tags to different kernel
  files, based on two different things:

   - SPDX entries are added to a bunch of files that we missed a year
     ago that do not have any license information at all.

     These were either missed because the tool saw the MODULE_LICENSE()
     tag, or some EXPORT_SYMBOL tags, and got confused and thought the
     file had a real license, or the files have been added since the
     last big sweep, or they were Makefile/Kconfig files, which we
     didn't touch last time.

   - Add GPL-2.0-only or GPL-2.0-or-later tags to files where our scan
     tools can determine the license text in the file itself. Where this
     happens, the license text is removed, in order to cut down on the
     700+ different ways we have in the kernel today, in a quest to get
     rid of all of these.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers.

  The reason for these "large" patches is if we were to continue to
  progress at the current rate of change in the kernel, adding license
  tags to individual files in different subsystems, we would be finished
  in about 10 years at the earliest.

  There will be more series of these types of patches coming over the
  next few weeks as the tools and reviewers crunch through the more
  "odd" variants of how to say "GPLv2" that developers have come up with
  over the years, combined with other fun oddities (GPL + a BSD
  disclaimer?) that are being unearthed, with the goal for the whole
  kernel to be cleaned up.

  These diffstats are not small, 3840 files are touched, over 10k lines
  removed in just 24 patches"

* tag 'spdx-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (24 commits)
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 24
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 23
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 22
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 21
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 20
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 19
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 17
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 15
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 14
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 12
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 11
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 10
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 9
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 7
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 5
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 4
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 3
  ...
2019-05-21 12:33:38 -07:00
Tom Zanussi 9b2ca371b1 tracing: Add a check_val() check before updating cond_snapshot() track_val
Without this check a snapshot is taken whenever a bucket's max is hit,
rather than only when the global max is hit, as it should be.

Before:

  In this example, we do a first run of the workload (cyclictest),
  examine the output, note the max ('triggering value') (347), then do
  a second run and note the max again.

  In this case, the max in the second run (39) is below the max in the
  first run, but since we haven't cleared the histogram, the first max
  is still in the histogram and is higher than any other max, so it
  should still be the max for the snapshot.  It isn't however - the
  value should still be 347 after the second run.

  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmax($wakeup_lat).save(next_prio,next_comm,prev_pid,prev_prio,prev_comm):onmax($wakeup_lat).snapshot() if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

  # cyclictest -p 80 -n -s -t 2 -D 2

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

  { next_pid:       2143 } hitcount:        199
    max:         44  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/4

  { next_pid:       2145 } hitcount:       1325
    max:         38  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/2

  { next_pid:       2144 } hitcount:       1982
    max:        347  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/6

  Snapshot taken (see tracing/snapshot).  Details:
      triggering value { onmax($wakeup_lat) }:        347
      triggered by event with key: { next_pid:       2144 }

  # cyclictest -p 80 -n -s -t 2 -D 2

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

  { next_pid:       2143 } hitcount:        199
    max:         44  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/4

  { next_pid:       2148 } hitcount:        199
    max:         16  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/1

  { next_pid:       2145 } hitcount:       1325
    max:         38  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/2

  { next_pid:       2150 } hitcount:       1326
    max:         39  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/4

  { next_pid:       2144 } hitcount:       1982
    max:        347  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/6

  { next_pid:       2149 } hitcount:       1983
    max:        130  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/0

  Snapshot taken (see tracing/snapshot).  Details:
    triggering value { onmax($wakeup_lat) }:    39
    triggered by event with key: { next_pid:       2150 }

After:

  In this example, we do a first run of the workload (cyclictest),
  examine the output, note the max ('triggering value') (375), then do
  a second run and note the max again.

  In this case, the max in the second run is still 375, the highest in
  any bucket, as it should be.

  # cyclictest -p 80 -n -s -t 2 -D 2

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

  { next_pid:       2072 } hitcount:        200
    max:         28  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/5

  { next_pid:       2074 } hitcount:       1323
    max:        375  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/2

  { next_pid:       2073 } hitcount:       1980
    max:        153  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/6

  Snapshot taken (see tracing/snapshot).  Details:
    triggering value { onmax($wakeup_lat) }:        375
    triggered by event with key: { next_pid:       2074 }

  # cyclictest -p 80 -n -s -t 2 -D 2

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

  { next_pid:       2101 } hitcount:        199
    max:         49  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/6

  { next_pid:       2072 } hitcount:        200
    max:         28  next_prio:        120  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/5

  { next_pid:       2074 } hitcount:       1323
    max:        375  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/2

  { next_pid:       2103 } hitcount:       1325
    max:         74  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/4

  { next_pid:       2073 } hitcount:       1980
    max:        153  next_prio:         19  next_comm: cyclictest
    prev_pid:          0  prev_prio:        120  prev_comm: swapper/6

  { next_pid:       2102 } hitcount:       1981
    max:         84  next_prio:         19  next_comm: cyclictest
    prev_pid:         12  prev_prio:        120  prev_comm: kworker/0:1

  Snapshot taken (see tracing/snapshot).  Details:
    triggering value { onmax($wakeup_lat) }:        375
    triggered by event with key: { next_pid:       2074 }

Link: http://lkml.kernel.org/r/95958351329f129c07504b4d1769c47a97b70d65.1555597045.git.tom.zanussi@linux.intel.com

Cc: stable@vger.kernel.org
Fixes: a3785b7eca ("tracing: Add hist trigger snapshot() action")
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-21 12:48:07 -04:00