From: Robert Richter robert.richter@linaro.org
rb_put() is called already in perf_event_release_kernel(), so no need to do the same in del_persistent_event(). We also don't need it in add_persistent_event_on_cpu() after a rework. Since there are no users of rb_put() anymore, we can make it private again to only events/core.c.
Signed-off-by: Robert Richter robert.richter@linaro.org Signed-off-by: Robert Richter rric@kernel.org --- kernel/events/core.c | 4 +++- kernel/events/internal.h | 1 - kernel/events/persistent.c | 29 +++++++++++------------------ 3 files changed, 14 insertions(+), 20 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index a9b6470..8f85caa 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3021,6 +3021,8 @@ static void free_event_rcu(struct rcu_head *head) kfree(event); }
+static void rb_put(struct ring_buffer *rb); + static void free_event(struct perf_event *event) { irq_work_sync(&event->pending); @@ -3680,7 +3682,7 @@ static struct ring_buffer *rb_get(struct perf_event *event) return rb; }
-void rb_put(struct ring_buffer *rb) +static void rb_put(struct ring_buffer *rb) { struct perf_event *event, *n; unsigned long flags; diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 3b481be..3647289 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -38,7 +38,6 @@ struct ring_buffer { extern void rb_free(struct ring_buffer *rb); extern struct ring_buffer * rb_alloc(int nr_pages, long watermark, int cpu, int flags); -extern void rb_put(struct ring_buffer *rb); extern void perf_event_wakeup(struct perf_event *event);
extern void diff --git a/kernel/events/persistent.c b/kernel/events/persistent.c index d7aaf95..e6a7664 100644 --- a/kernel/events/persistent.c +++ b/kernel/events/persistent.c @@ -20,22 +20,22 @@ static struct perf_event * add_persistent_event_on_cpu(unsigned int cpu, struct perf_event_attr *attr, unsigned nr_pages) { - struct perf_event *event = ERR_PTR(-ENOMEM); + struct perf_event *event; struct pers_event_desc *desc; struct ring_buffer *buf;
desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) - goto out; - - buf = rb_alloc(nr_pages, 0, cpu, 0); - if (!buf) - goto err_rb; + return ERR_PTR(-ENOMEM);
event = perf_event_create_kernel_counter(attr, cpu, NULL, NULL, NULL); if (IS_ERR(event)) goto err_event;
+ buf = rb_alloc(nr_pages, 0, cpu, 0); + if (!buf) + goto err_rb; + rcu_assign_pointer(event->rb, buf);
desc->event = event; @@ -47,14 +47,12 @@ add_persistent_event_on_cpu(unsigned int cpu, struct perf_event_attr *attr, perf_event_enable(event);
goto out; - - err_event: - rb_put(buf); - - err_rb: +err_rb: + perf_event_release_kernel(event); + event = ERR_PTR(-ENOMEM); +err_event: kfree(desc); - - out: +out: return event; }
@@ -76,11 +74,6 @@ static void del_persistent_event(int cpu, struct perf_event_attr *attr) list_del(&desc->plist);
perf_event_disable(event); - if (event->rb) { - rb_put(event->rb); - rcu_assign_pointer(event->rb, NULL); - } - perf_event_release_kernel(event); put_unused_fd(desc->fd); kfree(desc);