lib: percpu_count_sum()

Provide an accurate version of percpu_counter_read.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 17 insertions, 1 deletions

diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index dd89eb9783..21e054595b 100644
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -34,13 +34,24 @@ void percpu_counter_init(struct percpu_counter *fbc, s64 amount);
 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_positive(struct percpu_counter *fbc);
+s64 __percpu_counter_sum(struct percpu_counter *fbc);
 
 static inline void percpu_counter_add(struct percpu_counter *fbc, s64 amount)
 {
         __percpu_counter_add(fbc, amount, FBC_BATCH);
 }
 
+static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
+{
+        s64 ret = __percpu_counter_sum(fbc);
+        return ret < 0 ? 0 : ret;
+}
+
+static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
+{
+        return __percpu_counter_sum(fbc);
+}
+
 static inline s64 percpu_counter_read(struct percpu_counter *fbc)
 {
         return fbc->count;
@@ -107,6 +118,11 @@ static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
         return percpu_counter_read_positive(fbc);
 }
 
+static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
+{
+        return percpu_counter_read(fbc);
+}
+
 #endif  /* CONFIG_SMP */
 
 static inline void percpu_counter_inc(struct percpu_counter *fbc)