ring-buffer: Force rb_end_commit() and rb_set_commit_to_write() inline

Both rb_end_commit() and rb_set_commit_to_write() are in the fast path of
the ring buffer recording. Make sure they are always inlined.

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

@@ -2386,7 +2386,7 @@ static void rb_start_commit(struct ring_buffer_per_cpu *cpu_buffer)
 	local_inc(&cpu_buffer->commits);
 }
 
-static void
+static __always_inline void
 rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
 {
 	unsigned long max_count;
@@ -2441,7 +2441,7 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
 		goto again;
 }
 
-static inline void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)
+static __always_inline void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)
 {
 	unsigned long commits;