lkml.org 
[lkml]   [2013]   [Nov]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:perf/core] perf: Update a stale comment
Commit-ID:  394570b7939e1262f39373866166d8ee0a506e88
Gitweb: http://git.kernel.org/tip/394570b7939e1262f39373866166d8ee0a506e88
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Thu, 31 Oct 2013 17:41:23 +0100
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Wed, 6 Nov 2013 12:34:23 +0100

perf: Update a stale comment

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: james.hogan@imgtec.com
Cc: Vince Weaver <vince@deater.net>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Anton Blanchard <anton@samba.org>
Link: http://lkml.kernel.org/n/tip-9s5mze78gmlz19agt39i8rii@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
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);

\
 
 \ /
  Last update: 2013-11-06 15:01    [W:0.027 / U:0.504 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site