Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754299Ab3JDMG6 (ORCPT ); Fri, 4 Oct 2013 08:06:58 -0400 Received: from mail-wg0-f54.google.com ([74.125.82.54]:53777 "EHLO mail-wg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752741Ab3JDMG4 (ORCPT ); Fri, 4 Oct 2013 08:06:56 -0400 MIME-Version: 1.0 In-Reply-To: <1378895123.5476.83.camel@marge.simpson.net> References: <24EECBCC-F655-404F-8946-73CC36095A5F@gmail.com> <1378362989.18435.2.camel@marge.simpson.net> <20130905111428.GB23362@gmail.com> <1378386697.6567.9.camel@marge.simpson.net> <20130905133750.GA26637@gmail.com> <1378445942.5434.31.camel@marge.simpson.net> <20130909122325.GX31370@twins.programming.kicks-ass.net> <1378730538.5586.30.camel@marge.simpson.net> <20130909133044.GB31370@twins.programming.kicks-ass.net> <20130909134635.GB26785@twins.programming.kicks-ass.net> <20130911085643.GS26785@twins.programming.kicks-ass.net> <1378895123.5476.83.camel@marge.simpson.net> Date: Fri, 4 Oct 2013 20:06:55 +0800 Message-ID: Subject: Re: [PATCH V3]hrtimer: Fix a performance regression by disable reprogramming in remove_hrtimer From: Ethan Zhao To: Mike Galbraith Cc: Peter Zijlstra , Ingo Molnar , LKML , Thomas Gleixner , rjw@sisk.pl, daniel.lezcano@linaro.org, linux-pm@vger.kernel.org, lenb@kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2575 Lines: 61 Mike, Peter, Seems lots of work has been done these days, studious guys. those patches merged in last stable/dev branch (fix performance regression caused by extra rtimer programming and rescheduling IPI,confusing idle... etc) ? So I could just do a lazy pull for test with my environment. I need catch up with other mail loops with my vacation again. Thanks, Ethan On Wed, Sep 11, 2013 at 6:25 PM, Mike Galbraith wrote: > On Wed, 2013-09-11 at 10:56 +0200, Peter Zijlstra wrote: >> On Mon, Sep 09, 2013 at 03:46:35PM +0200, Peter Zijlstra wrote: >> > On Mon, Sep 09, 2013 at 03:30:44PM +0200, Peter Zijlstra wrote: >> > > diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c >> > > index fa6964d..486c0ba 100644 >> > > --- a/drivers/idle/intel_idle.c >> > > +++ b/drivers/idle/intel_idle.c >> > > @@ -359,6 +359,14 @@ static int intel_idle(struct cpuidle_device *dev, >> > > if (!(lapic_timer_reliable_states & (1 << (cstate)))) >> > > clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); >> > > >> > > + current_thread_into()->status |= TS_POLLING; >> > > + >> > > + /* >> > > + * Order against setting of TS_POLLING against the reading of >> > > + * NEED_RESCHED, matched by resched_task(). >> > > + */ >> > > + smp_mb(); >> > > + >> > > if (!need_resched()) { >> > > >> > > __monitor((void *)¤t_thread_info()->flags, 0, 0); >> > > @@ -367,6 +375,8 @@ static int intel_idle(struct cpuidle_device *dev, >> > > __mwait(eax, ecx); >> > > } >> > > >> > > + current_thread_into()->status &= ~TS_POLLING; >> > > + >> > > if (!(lapic_timer_reliable_states & (1 << (cstate)))) >> > > clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); >> > >> > Hmm, arguably it would be better to set this from >> > intel_idle_cpuidle_driver_init() and clear it whenever this goes away. >> > Not sure how all that works, the cpuidle driver framework seems 'weird'. >> >> OK, so I went over the idle stuff again, and we do set TS_POLLING like >> stuff, it got hidden in current_{clr,set}_polling(). >> >> Still if that patch causes extra IPIs its bound to be broken in some >> creative way.. I'll prod. > > (thanks, when I get a break from testing/poking this'n'that, I'll take a > peek too... well, good_intentions++ anyway;) > -- 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/