[RFC] trace_irqsoff: remove redundant reset per-CPU buff

From: Dmitry Safonov
Date: Mon Oct 19 2015 - 14:09:51 EST


There is no reason to do it twice: from commit b6f11df26fdc28
("trace: Call tracing_reset_online_cpus before tracer->init()")
resetting of per-CPU buffers done before tracer->init() call.

tracer->init() calls {irqs,preempt,preemptirqs}off_tracer_init() and it
calls __irqsoff_tracer_init(), which resets per-CPU ringbuffer second
time.
It's slowpath, but anyway.

Signed-off-by: Dmitry Safonov <0x7f454c46@xxxxxxxxx>
---
kernel/trace/trace_irqsoff.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 8523ea345f2b1a..4ebcb8bfaced24 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -612,7 +612,6 @@ static int __irqsoff_tracer_init(struct trace_array *tr)
irqsoff_trace = tr;
/* make sure that the tracer is visible */
smp_wmb();
- tracing_reset_online_cpus(&tr->trace_buffer);

ftrace_init_array_ops(tr, irqsoff_tracer_call);

--
2.6.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/