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| author | Tejun Heo <tj@kernel.org> | 2016-10-28 18:58:11 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-01-14 11:30:05 +0100 |
| commit | 1460cb65a10f6c7a6e3a1c76513338861a0a43b6 (patch) | |
| tree | 15c9773a766aea95828a609976a7bb8ba5dbbfc2 /kernel/locking | |
| parent | sched/core: Separate out io_schedule_prepare() and io_schedule_finish() (diff) | |
| download | linux-1460cb65a10f6c7a6e3a1c76513338861a0a43b6.tar.xz linux-1460cb65a10f6c7a6e3a1c76513338861a0a43b6.zip | |
locking/mutex, sched/wait: Add mutex_lock_io()
We sometimes end up propagating IO blocking through mutexes; however,
because there currently is no way of annotating mutex sleeps as
iowait, there are cases where iowait and /proc/stat:procs_blocked
report misleading numbers obscuring the actual state of the system.
This patch adds mutex_lock_io() so that mutex sleeps can be marked as
iowait in those cases.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: adilger.kernel@dilger.ca
Cc: jack@suse.com
Cc: kernel-team@fb.com
Cc: mingbo@fb.com
Cc: tytso@mit.edu
Link: http://lkml.kernel.org/r/1477673892-28940-4-git-send-email-tj@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/locking')
| -rw-r--r-- | kernel/locking/mutex.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 9b349619f431..8464a5cbab97 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -783,6 +783,20 @@ mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) } EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested); +void __sched +mutex_lock_io_nested(struct mutex *lock, unsigned int subclass) +{ + int token; + + might_sleep(); + + token = io_schedule_prepare(); + __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, + subclass, NULL, _RET_IP_, NULL, 0); + io_schedule_finish(token); +} +EXPORT_SYMBOL_GPL(mutex_lock_io_nested); + static inline int ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { @@ -950,6 +964,16 @@ int __sched mutex_lock_killable(struct mutex *lock) } EXPORT_SYMBOL(mutex_lock_killable); +void __sched mutex_lock_io(struct mutex *lock) +{ + int token; + + token = io_schedule_prepare(); + mutex_lock(lock); + io_schedule_finish(token); +} +EXPORT_SYMBOL_GPL(mutex_lock_io); + static noinline void __sched __mutex_lock_slowpath(struct mutex *lock) { |