From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932158AbcCSOQD (ORCPT ); Sat, 19 Mar 2016 10:16:03 -0400 Received: from mail.kernel.org ([198.145.29.136]:52585 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754167AbcCSOPo (ORCPT ); Sat, 19 Mar 2016 10:15:44 -0400 Message-Id: <20160319141537.409676968@goodmis.org> User-Agent: quilt/0.61-1 Date: Sat, 19 Mar 2016 10:15:24 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Dmitry Safonov <0x7f454c46@gmail.com> Subject: [for-next][PATCH 8/8] tracing: Remove redundant reset per-CPU buff in irqsoff tracer References: <20160319141516.683762867@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=0008-tracing-Remove-redundant-reset-per-CPU-buff-in-irqso.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Safonov <0x7f454c46@gmail.com> 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. Link: http://lkml.kernel.org/r/1445278226-16187-1-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Steven Rostedt --- 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 be3222b7d72e..03cdff84d026 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -626,7 +626,6 @@ 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); -- 2.7.0