Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759656AbZKFTOq (ORCPT ); Fri, 6 Nov 2009 14:14:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759625AbZKFTOp (ORCPT ); Fri, 6 Nov 2009 14:14:45 -0500 Received: from one.firstfloor.org ([213.235.205.2]:50568 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759584AbZKFTOp (ORCPT ); Fri, 6 Nov 2009 14:14:45 -0500 Date: Fri, 6 Nov 2009 20:14:48 +0100 From: Andi Kleen To: Christoph Lameter Cc: Andi Kleen , npiggin@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Ingo Molnar , KAMEZAWA Hiroyuki , "hugh.dickins@tiscali.co.uk" Subject: Re: [RFC MM] mmap_sem scaling: only scan cpus used by an mm Message-ID: <20091106191448.GD819@basil.fritz.box> References: <87r5sc7kst.fsf@basil.nowhere.org> <20091106073946.GV31511@one.firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 498 Lines: 12 On Fri, Nov 06, 2009 at 01:53:35PM -0500, Christoph Lameter wrote: > One way to reduce the cost of the writer lock is to track the cpus used > and loop over the processors in that bitmap. Can't you use the same mask as is used for TLB flushing? -Andi -- 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/