Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762953AbZD3OQ6 (ORCPT ); Thu, 30 Apr 2009 10:16:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754825AbZD3OQr (ORCPT ); Thu, 30 Apr 2009 10:16:47 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:40752 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758612AbZD3OQq (ORCPT ); Thu, 30 Apr 2009 10:16:46 -0400 Date: Thu, 30 Apr 2009 16:14:46 +0200 From: Ingo Molnar To: Christoph Lameter Cc: Mathieu Desnoyers , Linus Torvalds , Andrew Morton , Nick Piggin , KOSAKI Motohiro , Peter Zijlstra , thomas.pi@arcor.dea, Yuriy Lalym , Linux Kernel Mailing List , ltt-dev@lists.casi.polymtl.ca, Tejun Heo Subject: Re: [PATCH] Fix dirty page accounting in redirty_page_for_writepage() Message-ID: <20090430141446.GD14696@elte.hu> References: <20090429232546.GB15782@Krystal> <20090430024303.GB19875@Krystal> <20090430133859.GB8329@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1610 Lines: 56 * Christoph Lameter wrote: > On Thu, 30 Apr 2009, Ingo Molnar wrote: > > > it's all done, implemented and upstream already. You are a bit late > > to the party ;-) > > Just looked over it. Yep, now we just need to fix the things that > were messed up. Could we please skip over the lengthy flamewar and bad-mouthing of other people's work and go straight to the constructive portion of the discussion? ;-) The patch below makes the fallback/slowpath irq safe. Ingo diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 1581ff2..6b3984a 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -139,17 +139,23 @@ static inline void free_percpu(void *p) #ifndef percpu_read # define percpu_read(var) \ ({ \ + unsigned long flags; \ typeof(per_cpu_var(var)) __tmp_var__; \ - __tmp_var__ = get_cpu_var(var); \ - put_cpu_var(var); \ + \ + local_irq_save(flags); \ + __tmp_var__ = __get_cpu_var(var); \ + local_irq_restore(flags); \ __tmp_var__; \ }) #endif #define __percpu_generic_to_op(var, val, op) \ do { \ - get_cpu_var(var) op val; \ - put_cpu_var(var); \ + unsigned long flags; \ + \ + local_irq_save(flags); \ + op val; \ + local_irq_restore(flags); \ } while (0) #ifndef percpu_write -- 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/