Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752433AbXA1P0T (ORCPT ); Sun, 28 Jan 2007 10:26:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752438AbXA1P0T (ORCPT ); Sun, 28 Jan 2007 10:26:19 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:33769 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752433AbXA1P0S (ORCPT ); Sun, 28 Jan 2007 10:26:18 -0500 Date: Sun, 28 Jan 2007 16:24:35 +0100 From: Ingo Molnar To: Christoph Hellwig , Peter Zijlstra , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/7] barrier: a scalable synchonisation barrier Message-ID: <20070128152435.GC9196@elte.hu> References: <20070128115118.837777000@programming.kicks-ass.net> <20070128120509.719287000@programming.kicks-ass.net> <20070128143941.GA16552@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070128143941.GA16552@infradead.org> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -4.3 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-4.3 required=5.9 tests=ALL_TRUSTED,BAYES_00 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts -1.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 902 Lines: 22 * Christoph Hellwig wrote: > On Sun, Jan 28, 2007 at 12:51:21PM +0100, Peter Zijlstra wrote: > > This barrier thing is constructed so that it will not write in the > > sync() condition (the hot path) when there are no active lock > > sections; thus avoiding cacheline bouncing. -- I'm just not sure how > > this will work out in relation to PI. We might track those in the > > barrier scope and boost those by the max prio of the blockers. > > Is this really needed? We seem to grow new funky locking algorithms > exponentially, while people already have a hard time understanding the > existing ones. yes, it's needed. 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/