Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757167AbXFZKsG (ORCPT ); Tue, 26 Jun 2007 06:48:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752949AbXFZKrz (ORCPT ); Tue, 26 Jun 2007 06:47:55 -0400 Received: from mx10.go2.pl ([193.17.41.74]:59961 "EHLO poczta.o2.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752965AbXFZKry (ORCPT ); Tue, 26 Jun 2007 06:47:54 -0400 Date: Tue, 26 Jun 2007 12:56:02 +0200 From: Jarek Poplawski To: Nick Piggin Cc: Linus Torvalds , Eric Dumazet , Chuck Ebbert , Ingo Molnar , Miklos Szeredi , chris@atlee.ca, linux-kernel@vger.kernel.org, tglx@linutronix.de, akpm@linux-foundation.org Subject: Re: [BUG] long freezes on thinkpad t60 Message-ID: <20070626105602.GD2691@ff.dom.local> References: <20070620093612.GA1626@ff.dom.local> <20070621073031.GA683@elte.hu> <20070621160817.GA22897@elte.hu> <467AAB04.2070409@redhat.com> <20070621202917.a2bfbfc7.dada1@cosmosbay.com> <4680D162.9050603@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4680D162.9050603@yahoo.com.au> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1255 Lines: 29 On Tue, Jun 26, 2007 at 06:42:10PM +1000, Nick Piggin wrote: ... > They should also improve performance in heavily contended case due to > the nature of how they spin, but I know that's not something you want > to hear about. And theoretically there should be no reason why xadd is > any slower than dec and look at the status flags, should there? I never > implementedit in optimised assembly to test though... ... BTW, could you explain why the below diagnose doesn't relate to your solution? On 06/21/2007 12:08 PM, Ingo Molnar wrote: ... > So it seems the problem was that if a core kept _truly_ modifying a > cacheline via atomics in a high enough frequency, it could artificially > starve the other core. (which would keep waiting for the cacheline to be > released one day, and which kept the first core from ever making any > progress) To me that looks like a real problem on the hardware side - > shouldnt cacheline ownership be arbitrated a bit better than that? > Thanks & regards, Jarek P. - 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/