perf: Simplify the ring-buffer logic: make perf_buffer_alloc() do everything needed

Currently there are perf_buffer_alloc() + perf_buffer_init() + some
separate bits, fold it all into a single perf_buffer_alloc() and only
leave the attachment to the event separate.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 2a0da021c23f..441992a9775c 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -602,6 +602,8 @@ enum perf_event_active_state {
 
 struct file;
 
+#define PERF_BUFFER_WRITABLE            0x01
+
 struct perf_buffer {
         atomic_t                        refcount;
         struct rcu_head                 rcu_head;