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| author | Byungchul Park <byungchul.park@lge.com> | 2017-08-07 09:12:56 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-08-10 12:29:10 +0200 |
| commit | cd8084f91c02c1afd256a39aa833bff737631304 (patch) | |
| tree | a2eb7a1ce13798602affca1f244dbccc583b3952 /kernel/sched/completion.c | |
| parent | locking/lockdep: Make print_circular_bug() aware of crossrelease (diff) | |
| download | linux-cd8084f91c02c1afd256a39aa833bff737631304.tar.xz linux-cd8084f91c02c1afd256a39aa833bff737631304.zip | |
locking/lockdep: Apply crossrelease to completions
Although wait_for_completion() and its family can cause deadlock, the
lock correctness validator could not be applied to them until now,
because things like complete() are usually called in a different context
from the waiting context, which violates lockdep's assumption.
Thanks to CONFIG_LOCKDEP_CROSSRELEASE, we can now apply the lockdep
detector to those completion operations. Applied it.
Signed-off-by: Byungchul Park <byungchul.park@lge.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: akpm@linux-foundation.org
Cc: boqun.feng@gmail.com
Cc: kernel-team@lge.com
Cc: kirill@shutemov.name
Cc: npiggin@gmail.com
Cc: walken@google.com
Cc: willy@infradead.org
Link: http://lkml.kernel.org/r/1502089981-21272-10-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/completion.c')
| -rw-r--r-- | kernel/sched/completion.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c index 13fc5ae9bf2f..566b6ec7b6fe 100644 --- a/kernel/sched/completion.c +++ b/kernel/sched/completion.c @@ -32,6 +32,12 @@ void complete(struct completion *x) unsigned long flags; spin_lock_irqsave(&x->wait.lock, flags); + + /* + * Perform commit of crossrelease here. + */ + complete_release_commit(x); + if (x->done != UINT_MAX) x->done++; __wake_up_locked(&x->wait, TASK_NORMAL, 1); @@ -92,9 +98,14 @@ __wait_for_common(struct completion *x, { might_sleep(); + complete_acquire(x); + spin_lock_irq(&x->wait.lock); timeout = do_wait_for_common(x, action, timeout, state); spin_unlock_irq(&x->wait.lock); + + complete_release(x); + return timeout; } |