From: Peter Zijlstra provide a way to tell lockdep about percpu_counters that are supposed to be used from irq safe contexts. Signed-off-by: Peter Zijlstra Signed-off-by: Andrew Morton --- include/linux/percpu_counter.h | 3 +++ lib/percpu_counter.c | 12 ++++++++++++ 2 files changed, 15 insertions(+) diff -puN include/linux/percpu_counter.h~lib-percpu_counter_init_irq include/linux/percpu_counter.h --- a/include/linux/percpu_counter.h~lib-percpu_counter_init_irq +++ a/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) { } diff -puN lib/percpu_counter.c~lib-percpu_counter_init_irq lib/percpu_counter.c --- a/lib/percpu_counter.c~lib-percpu_counter_init_irq +++ a/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) _