linux_dsm_epyc7002/kernel/locking
Peter Zijlstra e6f3faa734 locking/lockdep: Fix workqueue crossrelease annotation
The new completion/crossrelease annotations interact unfavourable with
the extant flush_work()/flush_workqueue() annotations.

The problem is that when a single work class does:

  wait_for_completion(&C)

and

  complete(&C)

in different executions, we'll build dependencies like:

  lock_map_acquire(W)
  complete_acquire(C)

and

  lock_map_acquire(W)
  complete_release(C)

which results in the dependency chain: W->C->W, which lockdep thinks
spells deadlock, even though there is no deadlock potential since
works are ran concurrently.

One possibility would be to change the work 'lock' to recursive-read,
but that would mean hitting a lockdep limitation on recursive locks.
Also, unconditinoally switching to recursive-read here would fail to
detect the actual deadlock on single-threaded workqueues, which do
have a problem with this.

For now, forcefully disregard these locks for crossrelease.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boqun.feng@gmail.com
Cc: byungchul.park@lge.com
Cc: david@fromorbit.com
Cc: johannes@sipsolutions.net
Cc: oleg@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25 11:06:33 +02:00
..
lockdep_internals.h locking/lockdep: Avoid creating redundant links 2017-08-10 12:29:04 +02:00
lockdep_proc.c locking/lockdep: Avoid creating redundant links 2017-08-10 12:29:04 +02:00
lockdep_states.h locking/lockdep: Rework FS_RECLAIM annotation 2017-08-10 12:29:03 +02:00
lockdep.c locking/lockdep: Fix workqueue crossrelease annotation 2017-08-25 11:06:33 +02:00
locktorture.c sched/headers: Prepare for the removal of <linux/rtmutex.h> from <linux/sched.h> 2017-03-02 08:42:32 +01:00
Makefile locking/ww_mutex: Begin kselftests for ww_mutex 2017-01-14 11:37:14 +01:00
mcs_spinlock.h locking/core: Remove cpu_relax_lowlatency() users 2016-11-16 10:15:10 +01:00
mutex-debug.c locking/mutex: Rework mutex::owner 2016-10-25 11:31:50 +02:00
mutex-debug.h locking/mutex: Fix lockdep_assert_held() fail 2017-01-30 11:42:59 +01:00
mutex.c mutex, futex: adjust kernel-doc markups to generate ReST 2017-05-16 08:43:25 -03:00
mutex.h locking/mutex: Fix lockdep_assert_held() fail 2017-01-30 11:42:59 +01:00
osq_lock.c locking/osq_lock: Fix osq_lock queue corruption 2017-08-10 12:28:54 +02:00
percpu-rwsem.c locking/percpu-rwsem: Replace waitqueue with rcuwait 2017-01-14 11:14:35 +01:00
qrwlock.c kernel/locking: Fix compile error with qrwlock.c 2017-05-25 12:06:50 -07:00
qspinlock_paravirt.h mm: update callers to use HASH_ZERO flag 2017-07-06 16:24:33 -07:00
qspinlock_stat.h sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> 2017-03-02 08:42:27 +01:00
qspinlock.c locking/qspinlock: Explicitly include asm/prefetch.h 2017-07-08 11:01:11 +02:00
rtmutex_common.h futex: Allow for compiling out PI support 2017-08-01 14:36:35 +02:00
rtmutex-debug.c rt_mutex: Add lockdep annotations 2017-06-08 10:35:49 +02:00
rtmutex-debug.h rt_mutex: Add lockdep annotations 2017-06-08 10:35:49 +02:00
rtmutex.c locking/rtmutex: Remove unnecessary priority adjustment 2017-07-13 11:44:06 +02:00
rtmutex.h rt_mutex: Add lockdep annotations 2017-06-08 10:35:49 +02:00
rwsem-spinlock.c locking/rwsem-spinlock: Add killable versions of __down_read() 2017-08-10 12:28:55 +02:00
rwsem-xadd.c locking/rwsem-xadd: Add killable versions of rwsem_down_read_failed() 2017-08-10 12:28:55 +02:00
rwsem.c locking/lockdep: Add new check to lock_downgrade() 2017-03-16 09:57:07 +01:00
rwsem.h locking/rwsem: Protect all writes to owner by WRITE_ONCE() 2016-06-08 15:16:59 +02:00
semaphore.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h> 2017-03-02 08:42:34 +01:00
spinlock_debug.c locking/spinlock/debug: Remove spinlock lockup detection code 2017-02-10 09:09:49 +01:00
spinlock.c locking/spinlocks: Remove the unused spin_lock_bh_nested() API 2017-01-12 09:33:39 +01:00
test-ww_mutex.c locking/ww-mutex: Limit stress test to 2 seconds 2017-03-30 09:49:47 +02:00