summaryrefslogtreecommitdiffstats
path: root/ipc/msg.c
diff options
context:
space:
mode:
authorManfred Spraul <manfred@colorfullife.com>2020-02-03 17:34:42 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-02-04 03:05:24 +0000
commit8116b54e7e23ef948ecac0e0ab78d10888265cab (patch)
tree78124f712b73ade494a06d584fe9286f76180076 /ipc/msg.c
parent0d97a82ba830d89a1e541cc9cd11f1e38c28e416 (diff)
downloadlinux-8116b54e7e23ef948ecac0e0ab78d10888265cab.tar.gz
linux-8116b54e7e23ef948ecac0e0ab78d10888265cab.tar.bz2
linux-8116b54e7e23ef948ecac0e0ab78d10888265cab.zip
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/20191020123305.14715-6-manfred@colorfullife.com Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Cc: Waiman Long <longman@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: <1vier1@web.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc/msg.c')
0 files changed, 0 insertions, 0 deletions