[PATCH 05/23] lib: percpu_counter_set

Peter Zijlstra
2007-08-03T12:37:18Z

[-- Attachment #1: percpu_counter_set.patch --]
[-- Type: text/plain, Size: 2016 bytes --]

Provide a method to set a percpu counter to a specified value.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/linux/percpu_counter.h | 6 ++++++
lib/percpu_counter.c | 14 ++++++++++++++
2 files changed, 20 insertions(+)

Index: linux-2.6/include/linux/percpu_counter.h
===================================================================
--- linux-2.6.orig/include/linux/percpu_counter.h
+++ linux-2.6/include/linux/percpu_counter.h
@@ -32,6 +32,7 @@ struct percpu_counter {

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(struct percpu_counter *fbc);

@@ -75,6 +76,11 @@ static inline void percpu_counter_destro
{
}

+static inline void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
+{
+ fbc->count = amount;
+}
+
#define __percpu_counter_add(fbc, amount, batch) \
percpu_counter_add(fbc, amount)

Index: linux-2.6/lib/percpu_counter.c
===================================================================
--- linux-2.6.orig/lib/percpu_counter.c
+++ linux-2.6/lib/percpu_counter.c
@@ -14,6 +14,20 @@ static LIST_HEAD(percpu_counters);
static DEFINE_MUTEX(percpu_counters_lock);
#endif

+void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
+{
+ int cpu;
+
+ spin_lock(&fbc->lock);
+ for_each_possible_cpu(cpu) {
+ s32 *pcount = per_cpu_ptr(fbc->counters, cpu);
+ *pcount = 0;
+ }
+ fbc->count = amount;
+ spin_unlock(&fbc->lock);
+}
+EXPORT_SYMBOL(percpu_counter_set);
+
void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch)
{
s64 count;