perf: Remove the perf_output_begin(.sample) argument

Since only samples call perf_output_sample() its much saner (and more
correct) to put the sample logic in there than in the
perf_output_begin()/perf_output_end() pair.

Saves a useless argument, reduces conditionals and shrinks
struct perf_output_handle, win!

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-2crpvsx3cqu67q3zqjbnlpsc@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 21 insertions, 24 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index dbd1ca75bd3c..81de28dcca8c 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -3928,6 +3928,20 @@ void perf_output_sample(struct perf_output_handle *handle,
                         perf_output_put(handle, raw);
                 }
         }
+
+        if (!event->attr.watermark) {
+                int wakeup_events = event->attr.wakeup_events;
+
+                if (wakeup_events) {
+                        struct ring_buffer *rb = handle->rb;
+                        int events = local_inc_return(&rb->events);
+
+                        if (events >= wakeup_events) {
+                                local_sub(wakeup_events, &rb->events);
+                                local_inc(&rb->wakeup);
+                        }
+                }
+        }
 }
 
 void perf_prepare_sample(struct perf_event_header *header,
@@ -3984,7 +3998,7 @@ static void perf_event_output(struct perf_event *event,
 
         perf_prepare_sample(&header, data, event, regs);
 
-        if (perf_output_begin(&handle, event, header.size, 1))
+        if (perf_output_begin(&handle, event, header.size))
                 goto exit;
 
         perf_output_sample(&handle, &header, data, event);
@@ -4024,7 +4038,7 @@ perf_event_read_event(struct perf_event *event,
         int ret;
 
         perf_event_header__init_id(&read_event.header, &sample, event);
-        ret = perf_output_begin(&handle, event, read_event.header.size, 0);
+        ret = perf_output_begin(&handle, event, read_event.header.size);
         if (ret)
                 return;
 
@@ -4067,7 +4081,7 @@ static void perf_event_task_output(struct perf_event *event,
         perf_event_header__init_id(&task_event->event_id.header, &sample, event);
 
         ret = perf_output_begin(&handle, event,
-                                task_event->event_id.header.size, 0);
+                                task_event->event_id.header.size);
         if (ret)
                 goto out;
 
@@ -4204,7 +4218,7 @@ static void perf_event_comm_output(struct perf_event *event,
 
         perf_event_header__init_id(&comm_event->event_id.header, &sample, event);
         ret = perf_output_begin(&handle, event,
-                                comm_event->event_id.header.size, 0);
+                                comm_event->event_id.header.size);
 
         if (ret)
                 goto out;
@@ -4351,7 +4365,7 @@ static void perf_event_mmap_output(struct perf_event *event,
 
         perf_event_header__init_id(&mmap_event->event_id.header, &sample, event);
         ret = perf_output_begin(&handle, event,
-                                mmap_event->event_id.header.size, 0);
+                                mmap_event->event_id.header.size);
         if (ret)
                 goto out;
 
@@ -4546,7 +4560,7 @@ static void perf_log_throttle(struct perf_event *event, int enable)
         perf_event_header__init_id(&throttle_event.header, &sample, event);
 
         ret = perf_output_begin(&handle, event,
-                                throttle_event.header.size, 0);
+                                throttle_event.header.size);
         if (ret)
                 return;
 
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 8b3b73630fa4..a2a29205cc0f 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -98,8 +98,7 @@ out:
 }
 
 int perf_output_begin(struct perf_output_handle *handle,
-                      struct perf_event *event, unsigned int size,
-                      int sample)
+                      struct perf_event *event, unsigned int size)
 {
         struct ring_buffer *rb;
         unsigned long tail, offset, head;
@@ -124,7 +123,6 @@ int perf_output_begin(struct perf_output_handle *handle,
 
         handle->rb      = rb;
         handle->event   = event;
-        handle->sample  = sample;
 
         if (!rb->nr_pages)
                 goto out;
@@ -192,21 +190,6 @@ void perf_output_copy(struct perf_output_handle *handle,
 
 void perf_output_end(struct perf_output_handle *handle)
 {
-        struct perf_event *event = handle->event;
-        struct ring_buffer *rb = handle->rb;
-
-        if (handle->sample && !event->attr.watermark) {
-                int wakeup_events = event->attr.wakeup_events;
-
-                if (wakeup_events) {
-                        int events = local_inc_return(&rb->events);
-                        if (events >= wakeup_events) {
-                                local_sub(wakeup_events, &rb->events);
-                                local_inc(&rb->wakeup);
-                        }
-                }
-        }
-
         perf_output_put_handle(handle);
         rcu_read_unlock();
 }