lib/percpu_counter.c: __this_cpu_write() doesn't need to be protected by spinlock
__this_cpu_write doesn't need to be protected by spinlock, AS we are doing
per cpu write with preempt disabled. And another reason to remove
__this_cpu_write outside of spinlock: __percpu_counter_sum is not an
accurate counter.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index ba6085d..1fc23a3 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -80,8 +80,8 @@
if (count >= batch || count <= -batch) {
raw_spin_lock(&fbc->lock);
fbc->count += count;
- __this_cpu_write(*fbc->counters, 0);
raw_spin_unlock(&fbc->lock);
+ __this_cpu_write(*fbc->counters, 0);
} else {
__this_cpu_write(*fbc->counters, count);
}