Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750980AbWAJNLf (ORCPT ); Tue, 10 Jan 2006 08:11:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751000AbWAJNLf (ORCPT ); Tue, 10 Jan 2006 08:11:35 -0500 Received: from mail.tv-sign.ru ([213.234.233.51]:29612 "EHLO several.ru") by vger.kernel.org with ESMTP id S1750969AbWAJNLf (ORCPT ); Tue, 10 Jan 2006 08:11:35 -0500 Message-ID: <43C3C46C.D347F3F0@tv-sign.ru> Date: Tue, 10 Jan 2006 17:27:56 +0300 From: Oleg Nesterov X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.20 i686) X-Accept-Language: en MIME-Version: 1.0 To: vatsa@in.ibm.com Cc: "Paul E. McKenney" , linux-kernel@vger.kernel.org, Dipankar Sarma , Manfred Spraul , Linus Torvalds , Andrew Morton Subject: Re: [PATCH 2/5] rcu: don't check ->donelist in __rcu_pending() References: <43C165BC.F7C6DCF5@tv-sign.ru> <20060109185944.GB15083@us.ibm.com> <43C2C818.65238C30@tv-sign.ru> <20060109195933.GE14738@us.ibm.com> <20060110095811.GA30159@in.ibm.com> Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1393 Lines: 33 Srivatsa Vaddagiri wrote: > > On Mon, Jan 09, 2006 at 11:59:33AM -0800, Paul E. McKenney wrote: > > Hmmm... So your thought is that __rcu_offline_cpu() moves nxtlist and > > curlist, but not donelist, but then returns to rcu_offline_cpu(), which > > might well do the tasklet_kill_immediate() before the tasklet completed > > processing all of donelist. > > > > Seems plausible to me. If true, your patch adding the following statement > > to the ed of __rcu_offline_cpu seems like a reasonable fix: > > > > rcu_move_batch(this_rdp, rdp->donelist, rdp->donetail); > > > > Vatsa, is there something that Oleg and I are missing? > > I think this should take care of the CPU Hotplug bug, with the caveat > that the callbacks on ->donelist will wait for additional grace period before > being invoked (which seems ok). > > Oleg, do you want to resend the patch after some testing? Sure. The problem is that I have no idea how to test this change. However, the patch seems "obviously correct", so I am sending it. Srivatsa, I am sorry, I forgot to add you on CC: list while re-sending these cleanups. I hope you can see them on lkml. Oleg. - 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/