Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938444AbXHNFhE (ORCPT ); Tue, 14 Aug 2007 01:37:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934359AbXHNFgh (ORCPT ); Tue, 14 Aug 2007 01:36:37 -0400 Received: from www.osadl.org ([213.239.205.134]:38065 "EHLO mail.tglx.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S936507AbXHNFgf (ORCPT ); Tue, 14 Aug 2007 01:36:35 -0400 Subject: Re: [PATCH] hres_timers_resume must block interrupts From: Thomas Gleixner To: Joe Korty Cc: Ingo Molnar , linux-kernel@vger.kernel.org In-Reply-To: <20070813232626.GA24938@tsunami.ccur.com> References: <20070813232626.GA24938@tsunami.ccur.com> Content-Type: text/plain Date: Tue, 14 Aug 2007 07:36:30 +0200 Message-Id: <1187069790.12828.131.camel@chaos> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 (2.10.1-4.fc7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1500 Lines: 46 On Mon, 2007-08-13 at 19:26 -0400, Joe Korty wrote: > Retrigger_next_event() must be called with interrupts disabled. > > All internal (to hrtimer.c) uses of retrigger_next_event() are correct. > But the version exported to other files, hres_timers_resume(), does not > do the IRQ blocking, nor does the (single) external caller of it. > > Rather than require that users of hres_timers_resume() do the IRQ blocking, > this patch makes the blocking part of the hres_timers_resume() functionality. Ack. > (Also remove the meaningless WARN_ON_ONCE() call in hres_timers_resume) It's not that meaningless. It catched a resume order problem some time ago. tglx > Signed-off-by: Joe Korty (joe.korty@ccur.com) > > Index: 2.6.23-rc3/kernel/hrtimer.c > =================================================================== > --- 2.6.23-rc3.orig/kernel/hrtimer.c 2007-08-13 18:30:09.000000000 -0400 > +++ 2.6.23-rc3/kernel/hrtimer.c 2007-08-13 18:38:48.000000000 -0400 > @@ -463,10 +463,11 @@ > */ > void hres_timers_resume(void) > { > - WARN_ON_ONCE(num_online_cpus() > 1); > + unsigned long flags; > > - /* Retrigger the CPU local events: */ > + local_irq_save(flags); > retrigger_next_event(NULL); > + local_irq_restore(flags); > } > > /* > - 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/