Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030487Ab2HWK6a (ORCPT ); Thu, 23 Aug 2012 06:58:30 -0400 Received: from mail-qa0-f46.google.com ([209.85.216.46]:34740 "EHLO mail-qa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030301Ab2HWK6Z (ORCPT ); Thu, 23 Aug 2012 06:58:25 -0400 Date: Thu, 23 Aug 2012 12:58:19 +0200 From: Frederic Weisbecker To: Michael Cree Cc: LKML , Richard Henderson , Ivan Kokshaysky , Matt Turner , alpha , "Paul E. McKenney" , "3.2.x.." Subject: Re: [PATCH 01/10] alpha: Add missing RCU idle APIs on idle loop Message-ID: <20120823105816.GB18835@somewhere.redhat.com> References: <1345652628-15060-1-git-send-email-fweisbec@gmail.com> <1345652628-15060-2-git-send-email-fweisbec@gmail.com> <5035F8A2.1070702@orcon.net.nz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5035F8A2.1070702@orcon.net.nz> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1371 Lines: 33 On Thu, Aug 23, 2012 at 09:32:18PM +1200, Michael Cree wrote: > On 23/08/12 04:23, Frederic Weisbecker wrote: > > In the old times, the whole idle task was considered > > as an RCU quiescent state. But as RCU became more and > > more successful overtime, some RCU read side critical > > section have been added even in the code of some > > architectures idle tasks, for tracing for example. > > Fantastic! It fixes RCU CPU stalls that we were seeing on the SMP > kernel when built for generic Alpha. > > A build of glibc and running its test suite reliably triggers RCU CPU > stalls when running a kernel built for generic Alpha. I have just built > glibc and ran its test suite twice with no RCU CPU stalls with this > patch against a 3.5.2 kernel! Nice. Very nice. > > I see the stable queue is CCed but I note the patch does not apply > cleanly to the 3.2.y kernel. It would be nice to have a backport of the > patches for the 3.2 stable kernel. Sure. > > So feel free to add: > > Tested-by: Michael Cree Thanks, but I need to refactor the patch, I suspect a problem with CONFIG_PREEMPT. -- 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/