xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

locking/mutex, sched/wait: Add mutex_lock_io()

Browse Source 
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>
This commit is contained in:
Tejun Heo
2016-10-28 12:58:11 -04:00
committed by Ingo Molnar
parent 10ab56434f
commit 1460cb65a1
2 changed files with 28 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
kernel/locking/mutex.c
View File

@@ -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)
{