From 2182c98a8773f293361285aedc090b15aa0ae189 Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Wed, 15 Jul 2009 16:27:30 +0800 Subject: [PATCH] --- yaml --- r: 158400 b: refs/heads/master c: da706d8bc833e7153622435560422e653bdb2e94 h: refs/heads/master v: v3 --- [refs] | 2 +- trunk/kernel/trace/ring_buffer.c | 9 +++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/[refs] b/[refs] index d2db2b21a8f3..57f5b033525f 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: e202687927c132b1e1ff36b526b5e78ac33de840 +refs/heads/master: da706d8bc833e7153622435560422e653bdb2e94 diff --git a/trunk/kernel/trace/ring_buffer.c b/trunk/kernel/trace/ring_buffer.c index e648ba4f70e0..51633d74a21e 100644 --- a/trunk/kernel/trace/ring_buffer.c +++ b/trunk/kernel/trace/ring_buffer.c @@ -845,9 +845,14 @@ static int rb_tail_page_update(struct ring_buffer_per_cpu *cpu_buffer, * This will only succeed if an interrupt did * not come in and change it. In which case, we * do not want to modify it. + * + * We add (void) to let the compiler know that we do not care + * about the return value of these functions. We use the + * cmpxchg to only update if an interrupt did not already + * do it for us. If the cmpxchg fails, we don't care. */ - local_cmpxchg(&next_page->write, old_write, val); - local_cmpxchg(&next_page->entries, old_entries, eval); + (void)local_cmpxchg(&next_page->write, old_write, val); + (void)local_cmpxchg(&next_page->entries, old_entries, eval); /* * No need to worry about races with clearing out the commit.