Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758103AbZABQKP (ORCPT ); Fri, 2 Jan 2009 11:10:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756936AbZABQKB (ORCPT ); Fri, 2 Jan 2009 11:10:01 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:46510 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756907AbZABQKA (ORCPT ); Fri, 2 Jan 2009 11:10:00 -0500 Date: Fri, 2 Jan 2009 17:09:51 +0100 From: Ingo Molnar To: Ravikiran G Thirumalai Cc: linux-kernel@vger.kernel.org, travis@sgi.com Subject: Re: [patch] x86: Fix incorrect __read_mostly on _boot_cpu_pda Message-ID: <20090102160949.GF1180@elte.hu> References: <20081231214446.GA6856@localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081231214446.GA6856@localdomain> 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: 787 Lines: 19 * Ravikiran G Thirumalai wrote: > The pda rework (commit 3461b0af025251bbc6b3d56c821c6ac2de6f7209) > to remove static boot cpu pdas introduced a bug. _boot_cpu_pda is the > actual pda used by the boot cpu and is definitely not "__read_mostly" and > ended up polluting the read mostly section with writes. This bug caused > regression of about 8-10% on certain syscall intensive workloads. > > Signed-off-by: Ravikiran Thirumalai applied to tip/x86/urgent, with a Cc: stable tag. Thanks, Ingo -- 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/