revert "percpu_counter: new function percpu_counter_sum_and_set"
Revert
commit e8ced39d5e8911c662d4d69a342b9d053eaaac4e
Author: Mingming Cao <cmm@us.ibm.com>
Date: Fri Jul 11 19:27:31 2008 -0400
percpu_counter: new function percpu_counter_sum_and_set
As described in
revert "percpu counter: clean up percpu_counter_sum_and_set()"
the new percpu_counter_sum_and_set() is racy against updates to the
cpu-local accumulators on other CPUs. Revert that change.
This means that ext4 will be slow again. But correct.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index 2083888..9007ccd 100644
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -35,7 +35,7 @@
void percpu_counter_destroy(struct percpu_counter *fbc);
void percpu_counter_set(struct percpu_counter *fbc, s64 amount);
void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch);
-s64 __percpu_counter_sum(struct percpu_counter *fbc, int set);
+s64 __percpu_counter_sum(struct percpu_counter *fbc);
static inline void percpu_counter_add(struct percpu_counter *fbc, s64 amount)
{
@@ -44,19 +44,13 @@
static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
{
- s64 ret = __percpu_counter_sum(fbc, 0);
+ s64 ret = __percpu_counter_sum(fbc);
return ret < 0 ? 0 : ret;
}
-static inline s64 percpu_counter_sum_and_set(struct percpu_counter *fbc)
-{
- return __percpu_counter_sum(fbc, 1);
-}
-
-
static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
{
- return __percpu_counter_sum(fbc, 0);
+ return __percpu_counter_sum(fbc);
}
static inline s64 percpu_counter_read(struct percpu_counter *fbc)