[PATCH 09/23] lib: percpu_counter_init_irq

Peter Zijlstra
2007-08-03T12:58:49Z

[-- Attachment #1: percpu_counter_init_irq.patch --]
[-- Type: text/plain, Size: 1935 bytes --]

provide a way to init percpu_counters that are supposed to be used from irq
safe contexts.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/linux/percpu_counter.h | 3 +++
lib/percpu_counter.c | 12 ++++++++++++
2 files changed, 15 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
@@ -31,6 +31,7 @@ struct percpu_counter {
#endif

int percpu_counter_init(struct percpu_counter *fbc, s64 amount);
+int percpu_counter_init_irq(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);
@@ -84,6 +85,8 @@ static inline int percpu_counter_init(st
return 0;
}

+#define percpu_counter_init_irq percpu_counter_init
+
static inline void percpu_counter_destroy(struct percpu_counter *fbc)
{
}
Index: linux-2.6/lib/percpu_counter.c
===================================================================
--- linux-2.6.orig/lib/percpu_counter.c
+++ linux-2.6/lib/percpu_counter.c
@@ -68,6 +68,8 @@ s64 __percpu_counter_sum(struct percpu_c
}
EXPORT_SYMBOL(__percpu_counter_sum);

+static struct lock_class_key percpu_counter_irqsafe;
+
int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
{
spin_lock_init(&fbc->lock);
@@ -84,6 +86,16 @@ int percpu_counter_init(struct percpu_co
}
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;
+}
+
void percpu_counter_destroy(struct percpu_counter *fbc)
{
if (!fbc->counters)

--