| commit | 8116b54e7e23ef948ecac0e0ab78d10888265cab | [log] [tgz] |
|---|---|---|
| author | Manfred Spraul <[email protected]> | Mon Feb 03 17:34:42 2020 -0800 |
| committer | Linus Torvalds <[email protected]> | Tue Feb 04 03:05:24 2020 +0000 |
| tree | 78124f712b73ade494a06d584fe9286f76180076 | |
| parent | 0d97a82ba830d89a1e541cc9cd11f1e38c28e416 [diff] |
ipc/sem.c: document and update memory barriers Document and update the memory barriers in ipc/sem.c: - Add smp_store_release() to wake_up_sem_queue_prepare() and document why it is needed. - Read q->status using READ_ONCE+smp_acquire__after_ctrl_dep(). as the pair for the barrier inside wake_up_sem_queue_prepare(). - Add comments to all barriers, and mention the rules in the block regarding locking. - Switch to using wake_q_add_safe(). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Manfred Spraul <[email protected]> Cc: Waiman Long <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>