diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index fcdafa234a5..5f86a1156c9 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -46,9 +46,9 @@ static atomic_t nr_comm_tracking __read_mostly; int sysctl_perf_counter_priv __read_mostly; /* do we need to be privileged */ /* - * Mutex for (sysadmin-configurable) counter reservations: + * Lock for (sysadmin-configurable) counter reservations: */ -static DEFINE_MUTEX(perf_resource_mutex); +static DEFINE_SPINLOCK(perf_resource_lock); /* * Architecture provided APIs - weak aliases: @@ -3207,9 +3207,9 @@ static void __cpuinit perf_counter_init_cpu(int cpu) cpuctx = &per_cpu(perf_cpu_context, cpu); __perf_counter_init_context(&cpuctx->ctx, NULL); - mutex_lock(&perf_resource_mutex); + spin_lock(&perf_resource_lock); cpuctx->max_pertask = perf_max_counters - perf_reserved_percpu; - mutex_unlock(&perf_resource_mutex); + spin_unlock(&perf_resource_lock); hw_perf_counter_setup(cpu); } @@ -3292,7 +3292,7 @@ perf_set_reserve_percpu(struct sysdev_class *class, if (val > perf_max_counters) return -EINVAL; - mutex_lock(&perf_resource_mutex); + spin_lock(&perf_resource_lock); perf_reserved_percpu = val; for_each_online_cpu(cpu) { cpuctx = &per_cpu(perf_cpu_context, cpu); @@ -3302,7 +3302,7 @@ perf_set_reserve_percpu(struct sysdev_class *class, cpuctx->max_pertask = mpt; spin_unlock_irq(&cpuctx->ctx.lock); } - mutex_unlock(&perf_resource_mutex); + spin_unlock(&perf_resource_lock); return count; } @@ -3324,9 +3324,9 @@ perf_set_overcommit(struct sysdev_class *class, const char *buf, size_t count) if (val > 1) return -EINVAL; - mutex_lock(&perf_resource_mutex); + spin_lock(&perf_resource_lock); perf_overcommit = val; - mutex_unlock(&perf_resource_mutex); + spin_unlock(&perf_resource_lock); return count; }