[PATCH] percpu_counter_sum()
Implement percpu_counter_sum(). This is a more accurate but slower version of
percpu_counter_read_positive().
We need this for Alex's speedup-ext3_statfs patch and for the nr_file
accounting fix. Otherwise these things would be too inaccurate on large CPU
counts.
Cc: Ravikiran G Thirumalai <kiran@scalex86.org>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index bd6708e..6825255 100644
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -39,6 +39,7 @@
}
void percpu_counter_mod(struct percpu_counter *fbc, long amount);
+long percpu_counter_sum(struct percpu_counter *fbc);
static inline long percpu_counter_read(struct percpu_counter *fbc)
{
@@ -92,6 +93,11 @@
return fbc->count;
}
+static inline long percpu_counter_sum(struct percpu_counter *fbc)
+{
+ return percpu_counter_read_positive(fbc);
+}
+
#endif /* CONFIG_SMP */
static inline void percpu_counter_inc(struct percpu_counter *fbc)