Commit-ID: 394570b7939e1262f39373866166d8ee0a506e88 Gitweb: http://git.kernel.org/tip/394570b7939e1262f39373866166d8ee0a506e88 Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Thu, 31 Oct 2013 17:41:23 +0100 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Wed, 6 Nov 2013 12:34:23 +0100 perf: Update a stale comment Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx> Cc: Michael Ellerman <michael@xxxxxxxxxxxxxx> Cc: Michael Neuling <mikey@xxxxxxxxxxx> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> Cc: james.hogan@xxxxxxxxxx Cc: Vince Weaver <vince@xxxxxxxxxx> Cc: Victor Kaplansky <VICTORK@xxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Anton Blanchard <anton@xxxxxxxxx> Link: http://lkml.kernel.org/n/tip-9s5mze78gmlz19agt39i8rii@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- kernel/events/ring_buffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index c52a32f..e8b168a 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -85,8 +85,8 @@ again: rb->user_page->data_head = head; /* - * Now check if we missed an update, rely on the (compiler) - * barrier in atomic_dec_and_test() to re-read rb->head. + * Now check if we missed an update -- rely on previous implied + * compiler barriers to force a re-read. */ if (unlikely(head != local_read(&rb->head))) { local_inc(&rb->nest); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html