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[for-next][PATCH 2/8] ring-buffer: Make rb_reserve_next_event() always inlined

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From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

The function rb_reserved_next_event() is called by two functions:
ring_buffer_lock_reserve() and ring_buffer_write(). This is in a very hot
path of the tracing code, and it is best that they are not functions. The
two callers are basically wrapers for rb_reserver_next_event(). Removing the
function calls can save execution time in the hotpath of tracing.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/ring_buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 9c143739b8d7..1f3580cee6cc 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2733,7 +2733,7 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
 	return event;
 }
 
-static struct ring_buffer_event *
+static __always_inline struct ring_buffer_event *
 rb_reserve_next_event(struct ring_buffer *buffer,
 		      struct ring_buffer_per_cpu *cpu_buffer,
 		      unsigned long length)
-- 
2.10.2

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[for-next][PATCH 0/8] tracing: Some micro optimizations Steven Rostedt <rostedt@goodmis.org> - 2016-11-29 16:20 +0100
  [for-next][PATCH 6/8] ring-buffer: Force inline of hotpath helper functions Steven Rostedt <rostedt@goodmis.org> - 2016-11-29 16:20 +0100
  [for-next][PATCH 3/8] ring-buffer: Always inline rb_event_data() Steven Rostedt <rostedt@goodmis.org> - 2016-11-29 16:20 +0100
  [for-next][PATCH 5/8] tracing: Make __buffer_unlock_commit() always_inline Steven Rostedt <rostedt@goodmis.org> - 2016-11-29 16:20 +0100
  [for-next][PATCH 2/8] ring-buffer: Make rb_reserve_next_event() always inlined Steven Rostedt <rostedt@goodmis.org> - 2016-11-29 16:20 +0100

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