Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262785AbVBCLCE (ORCPT ); Thu, 3 Feb 2005 06:02:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262994AbVBCK55 (ORCPT ); Thu, 3 Feb 2005 05:57:57 -0500 Received: from gprs214-42.eurotel.cz ([160.218.214.42]:2432 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S262770AbVBCK5M (ORCPT ); Thu, 3 Feb 2005 05:57:12 -0500 Date: Thu, 3 Feb 2005 11:56:47 +0100 From: Pavel Machek To: Tony Lindgren Cc: Benjamin Herrenschmidt , Arjan van de Ven , Martin Schwidefsky , Andrea Arcangeli , George Anzinger , Thomas Gleixner , john stultz , Zwane Mwaikambo , Lee Revell , linux-kernel@vger.kernel.org Subject: Re: [PATCH] Dynamic tick, version 050127-1 Message-ID: <20050203105647.GA1369@elf.ucw.cz> References: <20050127212902.GF15274@atomide.com> <20050201110006.GA1338@elf.ucw.cz> <20050201204008.GD14274@atomide.com> <20050201212542.GA3691@openzaurus.ucw.cz> <20050201230357.GH14274@atomide.com> <20050202141105.GA1316@elf.ucw.cz> <20050203030359.GL13984@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050203030359.GL13984@atomide.com> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.6+20040907i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2489 Lines: 59 Hi! > > > > > > I used your config advices from second mail, still it does not work as > > > > > > expected: system gets "too sleepy". Like it takes a nap during boot > > > > > > after "dyn-tick: Maximum ticks to skip limited to 1339", and key is > > > > > > needed to make it continue boot. Then cursor stops blinking and > > > > > > machine is hung at random intervals during use, key is enough to awake > > > > > > it. > > > > > > > > > > Hmmm, that sounds like the local APIC does not wake up the PIT > > > > > interrupt properly after sleep. Hitting the keys causes the timer > > > > > interrupt to get called, and that explains why it keeps running. But > > > > > the timer ticks are not happening as they should for some reason. > > > > > This should not happen (tm)... > > > > > > > > :-). Any ideas how to debug it? Previous version of patch seemed to work better... > > > > > > I don't think it's HPET timer, or CONFIG_SMP. It also looks like your > > > local APIC timer is working. > > > > I turned off CONFIG_PREEMPT, but nothing changed :-(. > > What about reprogramming the timers in time.c after the sleep? Do > you to dyn_tick->skip = 1; part in dyn_tick_timer_interrupt? Yes, when I enabled debugging, dbg_dyn_tick_irq() was reached and produced lot of noise to syslog. After I done nothing for a while, machine would just sit there and wait, not doing anything. When it was hung, dbg_dyn_timer_tick was not reached. > It could also be that the reprogamming of PIT timer does not work on > your machine. I chopped off the udelays there... Can you try > something like this: I added the udelays, but behaviour did not change. > --- a/arch/i386/kernel/time.c 2005-01-27 12:58:04 -08:00 > +++ b/arch/i368/kernel/time.c 2005-02-02 19:01:31 -08:00 > @@ -479,8 +480,11 @@ > > spin_lock_irqsave(&i8253_lock, flags); > outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */ > + udelay(10); > outb_p(skip & 0xff, PIT_CH0); /* LSB */ > + udelay(10); > outb(skip >> 8, PIT_CH0); /* MSB */ > + udelay(10); > spin_unlock_irqrestore(&i8253_lock, flags); > } > Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl! - 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/