Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754014Ab1BUHYb (ORCPT ); Mon, 21 Feb 2011 02:24:31 -0500 Received: from cantor2.suse.de ([195.135.220.15]:46482 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752228Ab1BUHYa (ORCPT ); Mon, 21 Feb 2011 02:24:30 -0500 Date: Mon, 21 Feb 2011 18:24:19 +1100 From: NeilBrown To: Vivek Goyal Cc: Mike Snitzer , Jens Axboe , linux-kernel@vger.kernel.org Subject: Re: blk_throtl_exit taking q->queue_lock is problematic Message-ID: <20110221182419.3545cdbb@notabene.brown> In-Reply-To: <20110218150429.GB26654@redhat.com> References: <20110216183114.26a3613b@notabene.brown> <20110216155305.GC14653@redhat.com> <20110217113536.2bbf308e@notabene.brown> <20110217011029.GA6793@redhat.com> <20110217165501.47f3c26f@notabene.brown> <20110217165906.GE9075@redhat.com> <20110218134025.2a2e5bbb@notabene.brown> <20110218143325.5738e127@notabene.brown> <20110218150429.GB26654@redhat.com> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.20.1; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1190 Lines: 30 On Fri, 18 Feb 2011 10:04:29 -0500 Vivek Goyal wrote: > On Fri, Feb 18, 2011 at 02:33:25PM +1100, NeilBrown wrote: > > On Thu, 17 Feb 2011 22:19:52 -0500 Mike Snitzer wrote: > > > Noticed an inconsistency, raid10.c's additional locking also protects > > > the bio_list_add() whereas raid1.c's doesn't. Seems the additional > > > protection in raid10 isn't needed? > > > > Correct - not needed at all. > > I put it there because it felt a little cleaner keeping the two 'lock's > > together like the two 'unlock's. Probably confusing though... > > I guess you could use blk_plug_device_unlocked() to get rid of ugliness > and this routine will take care of taking queue lock. > Yep, that gets rid of some ugliness. I've made that change and will submit it in due course. So blk_throtl doesn't need any change to avoid the problem with md - that changes are made in md instead. Thanks, NeilBrown -- 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/