aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--include/linux/perf_event.h1
-rw-r--r--kernel/perf_event.c21
2 files changed, 11 insertions, 11 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index df4e73e33774..7f87563c8485 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -714,7 +714,6 @@ struct perf_output_handle {
int nmi;
int sample;
int locked;
- unsigned long flags;
};
#ifdef CONFIG_PERF_EVENTS
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 6f4ed3b4cd73..3256e36ad251 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2674,20 +2674,21 @@ static void perf_output_wakeup(struct perf_output_handle *handle)
static void perf_output_lock(struct perf_output_handle *handle)
{
struct perf_mmap_data *data = handle->data;
- int cpu;
+ int cur, cpu = get_cpu();
handle->locked = 0;
- local_irq_save(handle->flags);
- cpu = smp_processor_id();
-
- if (in_nmi() && atomic_read(&data->lock) == cpu)
- return;
+ for (;;) {
+ cur = atomic_cmpxchg(&data->lock, -1, cpu);
+ if (cur == -1) {
+ handle->locked = 1;
+ break;
+ }
+ if (cur == cpu)
+ break;
- while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
cpu_relax();
-
- handle->locked = 1;
+ }
}
static void perf_output_unlock(struct perf_output_handle *handle)
@@ -2733,7 +2734,7 @@ again:
if (atomic_xchg(&data->wakeup, 0))
perf_output_wakeup(handle);
out:
- local_irq_restore(handle->flags);
+ put_cpu();
}
void perf_output_copy(struct perf_output_handle *handle,