tree 21f19b4f4ddcf219c7b024c2cf7ffbac9d0a80b8
parent daf948c7d1a080041ae19aca07625efec670695a
author Davidlohr Bueso <davidlohr@hp.com> 1390871230 -0800
committer Linus Torvalds <torvalds@linux-foundation.org> 1390885360 -0800

ipc,msg: document barriers

Both expunge_all() and pipeline_send() rely on both a nil msg value and
a full barrier to guarantee the correct ordering when waking up a task.

While its counterpart at the receiving end is well documented for the
lockless recv algorithm, we still need to document these specific
smp_mb() calls.

[akpm@linux-foundation.org: fix typo, per Mike]
[akpm@linux-foundation.org: mroe tpyos]
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>