From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265789AbUHALGP (ORCPT ); Sun, 1 Aug 2004 07:06:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265795AbUHALGP (ORCPT ); Sun, 1 Aug 2004 07:06:15 -0400 Received: from mx1.redhat.com ([66.187.233.31]:2514 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S265789AbUHALGN (ORCPT ); Sun, 1 Aug 2004 07:06:13 -0400 Date: Sun, 1 Aug 2004 07:05:17 -0400 (EDT) From: Ingo Molnar X-X-Sender: mingo@devserv.devel.redhat.com To: Andrew Morton cc: Zwane Mwaikambo , linux-kernel@vger.kernel.org, mingo@elte.hu Subject: Re: 2.6.8-rc2-mm1 In-Reply-To: <20040731114714.37359c2d.akpm@osdl.org> Message-ID: References: <20040728020444.4dca7e23.akpm@osdl.org> <20040731114714.37359c2d.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 31 Jul 2004, Andrew Morton wrote: > > Ingo i believe you have a patch for this, could you push it to Andrew? > > I suspect Ingo's patch will be livelockable under some circumstances. the first versions were - i could even reproduce it. Fixed it up by doing less work in this function. But i like your solution of rotating the list too. Anyway, the -M5 patch shouldnt be livelockable. (but it might have the crash problem). btw., breaking the outer loop here is not enough for latencies, it needs to happen in the inner loop. (which can take thousands of iterations too.) See the checkpoint.c bits of the -M5 patch: http://people.redhat.com/mingo/voluntary-preempt/voluntary-preempt-2.6.8-rc2-mm1-M5 Ingo