summaryrefslogtreecommitdiffstats
path: root/kernel/trace/ring_buffer.c
diff options
context:
space:
mode:
authorSteven Rostedt (Red Hat) <rostedt@goodmis.org>2015-03-27 17:39:49 -0400
committerSteven Rostedt <rostedt@goodmis.org>2015-03-30 13:36:31 -0400
commitd631c8cceb1d1d06f372878935949d421585186b (patch)
tree7a213ad0e5ede27961a63eb97bbc361309c4a599 /kernel/trace/ring_buffer.c
parentd9a16d3ab8770357015c85a07387f1d2676a4773 (diff)
downloadlinux-d631c8cceb1d1d06f372878935949d421585186b.tar.bz2
ring-buffer: Remove duplicate use of '&' in recursive code
A clean up of the recursive protection code changed val = this_cpu_read(current_context); val--; val &= this_cpu_read(current_context); to val = this_cpu_read(current_context); val &= val & (val - 1); Which has a duplicate use of '&' as the above is the same as val = val & (val - 1); Actually, it would be best to remove that line altogether and just add it to where it is used. And Christoph even mentioned that it can be further compacted to just a single line: __this_cpu_and(current_context, __this_cpu_read(current_context) - 1); Link: http://lkml.kernel.org/alpine.DEB.2.11.1503271423580.23114@gentwo.org Suggested-by: Christoph Lameter <cl@linux.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c5
1 files changed, 1 insertions, 4 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 922048a0f7ea..0315d43176d8 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2703,10 +2703,7 @@ static __always_inline int trace_recursive_lock(void)
static __always_inline void trace_recursive_unlock(void)
{
- unsigned int val = __this_cpu_read(current_context);
-
- val &= val & (val - 1);
- __this_cpu_write(current_context, val);
+ __this_cpu_and(current_context, __this_cpu_read(current_context) - 1);
}
#else