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

From: Steven Rostedt
Date: Tue Nov 29 2016 - 10:14:47 EST

From: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxx

Reported-by: Andi Kleen <andi@xxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
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)