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Diffstat (limited to 'lib/percpu_counter.c')
-rw-r--r--lib/percpu_counter.c36
1 files changed, 18 insertions, 18 deletions
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index b255b939bc1b..aeaa6d734447 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -9,10 +9,8 @@
#include <linux/cpu.h>
#include <linux/module.h>
-#ifdef CONFIG_HOTPLUG_CPU
static LIST_HEAD(percpu_counters);
static DEFINE_MUTEX(percpu_counters_lock);
-#endif
void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
{
@@ -68,11 +66,11 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc)
}
EXPORT_SYMBOL(__percpu_counter_sum);
-static struct lock_class_key percpu_counter_irqsafe;
-
-int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
+int __percpu_counter_init(struct percpu_counter *fbc, s64 amount,
+ struct lock_class_key *key)
{
spin_lock_init(&fbc->lock);
+ lockdep_set_class(&fbc->lock, key);
fbc->count = amount;
fbc->counters = alloc_percpu(s32);
if (!fbc->counters)
@@ -84,17 +82,7 @@ int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
#endif
return 0;
}
-EXPORT_SYMBOL(percpu_counter_init);
-
-int percpu_counter_init_irq(struct percpu_counter *fbc, s64 amount)
-{
- int err;
-
- err = percpu_counter_init(fbc, amount);
- if (!err)
- lockdep_set_class(&fbc->lock, &percpu_counter_irqsafe);
- return err;
-}
+EXPORT_SYMBOL(__percpu_counter_init);
void percpu_counter_destroy(struct percpu_counter *fbc)
{
@@ -111,13 +99,24 @@ void percpu_counter_destroy(struct percpu_counter *fbc)
}
EXPORT_SYMBOL(percpu_counter_destroy);
-#ifdef CONFIG_HOTPLUG_CPU
+int percpu_counter_batch __read_mostly = 32;
+EXPORT_SYMBOL(percpu_counter_batch);
+
+static void compute_batch_value(void)
+{
+ int nr = num_online_cpus();
+
+ percpu_counter_batch = max(32, nr*2);
+}
+
static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb,
unsigned long action, void *hcpu)
{
+#ifdef CONFIG_HOTPLUG_CPU
unsigned int cpu;
struct percpu_counter *fbc;
+ compute_batch_value();
if (action != CPU_DEAD)
return NOTIFY_OK;
@@ -134,13 +133,14 @@ static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb,
spin_unlock_irqrestore(&fbc->lock, flags);
}
mutex_unlock(&percpu_counters_lock);
+#endif
return NOTIFY_OK;
}
static int __init percpu_counter_startup(void)
{
+ compute_batch_value();
hotcpu_notifier(percpu_counter_hotcpu_callback, 0);
return 0;
}
module_init(percpu_counter_startup);
-#endif