Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932146AbZISLgm (ORCPT ); Sat, 19 Sep 2009 07:36:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757697AbZISLgg (ORCPT ); Sat, 19 Sep 2009 07:36:36 -0400 Received: from casper.infradead.org ([85.118.1.10]:50795 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757578AbZISLga convert rfc822-to-8bit (ORCPT ); Sat, 19 Sep 2009 07:36:30 -0400 Date: Sat, 19 Sep 2009 13:35:33 +0200 From: Arjan van de Ven To: mingo@elte.hu Cc: Arjan van de Ven , linux-kernel@vger.kernel.org, fweisbec@gmail.com, peterz@infradead.org, Paul Mackerras Subject: [PATCH] trace: Move the end point of a C state in the power tracer Message-ID: <20090919133533.139c2a46@infradead.org> In-Reply-To: <20090919133410.7b23e270@infradead.org> References: <20090919133410.7b23e270@infradead.org> Organization: Intel X-Mailer: Claws Mail 3.7.2 (GTK+ 2.14.7; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2511 Lines: 82 >From c1ffb79a8e87501ccaf269517566f438220f1c49 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sat, 19 Sep 2009 13:09:16 +0200 Subject: [PATCH] trace: Move the end point of a C state in the power tracer The "end of a C state" trace point currently happens before the code runs that corrects the TSC for having stopped during idle. The result of this is that the timestamp of the end-of-C-state event is garbage on cpus where the TSC stops during idle. This patch moves the end point of the C state to after the timekeeping engine of the kernel has been corrected. Signed-off-by: Arjan van de Ven --- arch/x86/kernel/process.c | 3 --- drivers/cpuidle/cpuidle.c | 2 ++ 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 98e9cac..230d054 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -299,7 +299,6 @@ void default_idle(void) else local_irq_enable(); current_thread_info()->status |= TS_POLLING; - trace_power_end(0); } else { local_irq_enable(); /* loop is done by the caller */ @@ -367,7 +366,6 @@ void mwait_idle_with_hints(unsigned long ax, unsigned long cx) if (!need_resched()) __mwait(ax, cx); } - trace_power_end(0); } /* Default MONITOR/MWAIT with no hints, used for default C1 state */ @@ -384,7 +382,6 @@ static void mwait_idle(void) __sti_mwait(0, 0); else local_irq_enable(); - trace_power_end(0); } else local_irq_enable(); } diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 8504a21..ad41f19 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "cpuidle.h" @@ -91,6 +92,7 @@ static void cpuidle_idle_call(void) /* give the governor an opportunity to reflect on the outcome */ if (cpuidle_curr_governor->reflect) cpuidle_curr_governor->reflect(dev); + trace_power_end(0); } /** -- 1.6.0.6 -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/