Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753786AbYKPVZ7 (ORCPT ); Sun, 16 Nov 2008 16:25:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753058AbYKPVZU (ORCPT ); Sun, 16 Nov 2008 16:25:20 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:49062 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752749AbYKPVZR (ORCPT ); Sun, 16 Nov 2008 16:25:17 -0500 Message-Id: <20081116212515.093117788@goodmis.org> References: <20081116212428.938752312@goodmis.org> User-Agent: quilt/0.46-1 Date: Sun, 16 Nov 2008 16:24:29 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Thomas Gleixner , Peter Zijlstra , David Miller , Benjamin Herrenschmidt , Frederic Weisbecker , Pekka Paalanen , linuxppc-dev@ozlabs.org, Rusty Russell , Paul Mackerras , Paul Mundt , Steven Rostedt Subject: [PATCH 1/7] ftrace, PPC: do not latency trace idle Content-Disposition: inline; filename=0001-ftrace-PPC-do-not-latency-trace-idle.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1362 Lines: 44 Impact: give better timing to latency tracers When idle is called, interrupts are disabled, but the idle function will still wake up on an interrupt. The problem is that the interrupt disabled latency tracer will take this call to idle as a latency. This patch disables the latency tracing when going into idle. Signed-off-by: Steven Rostedt CC: Paul Mackerras CC: Benjamin Herrenschmidt --- arch/powerpc/kernel/idle.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c index 31982d0..88d9c1d 100644 --- a/arch/powerpc/kernel/idle.c +++ b/arch/powerpc/kernel/idle.c @@ -69,10 +69,15 @@ void cpu_idle(void) smp_mb(); local_irq_disable(); + /* Don't trace irqs off for idle */ + stop_critical_timings(); + /* check again after disabling irqs */ if (!need_resched() && !cpu_should_die()) ppc_md.power_save(); + start_critical_timings(); + local_irq_enable(); set_thread_flag(TIF_POLLING_NRFLAG); -- 1.5.6.5 -- -- 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/