Commit d9abde21 authored by Steven Rostedt's avatar Steven Rostedt Committed by Steven Rostedt
Browse files

ring-buffer: Micro-optimize with some strategic inlining 



By using inline and noinline, we are able to make the fast path of
recording an event 4% faster.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 140ff891

kernel/trace/ring_buffer.c

+15 −8
Original line number Diff line number Diff line
@@ -2078,7 +2078,7 @@ static void rb_start_commit(struct ring_buffer_per_cpu *cpu_buffer) 
	local_inc(&cpu_buffer->commits);

}



static void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)

static inline void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)

{

	unsigned long commits;
@@ -2193,13 +2193,9 @@ rb_reserve_next_event(struct ring_buffer *buffer, 


#define TRACE_RECURSIVE_DEPTH 16



static int trace_recursive_lock(void)

/* Keep this code out of the fast path cache */

static noinline void trace_recursive_fail(void)

{

	current->trace_recursion++;



	if (likely(current->trace_recursion < TRACE_RECURSIVE_DEPTH))

		return 0;



	/* Disable all tracing before we do anything else */

	tracing_off_permanent();
@@ -2211,10 +2207,21 @@ static int trace_recursive_lock(void) 
		    in_nmi());



	WARN_ON_ONCE(1);

}



static inline int trace_recursive_lock(void)

{

	current->trace_recursion++;



	if (likely(current->trace_recursion < TRACE_RECURSIVE_DEPTH))

		return 0;



	trace_recursive_fail();



	return -1;

}



static void trace_recursive_unlock(void)

static inline void trace_recursive_unlock(void)

{

	WARN_ON_ONCE(!current->trace_recursion);