Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753926Ab1CGUeU (ORCPT ); Mon, 7 Mar 2011 15:34:20 -0500 Received: from mx1.fusionio.com ([64.244.102.30]:40548 "EHLO mx1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752072Ab1CGUeT (ORCPT ); Mon, 7 Mar 2011 15:34:19 -0500 X-ASG-Debug-ID: 1299530056-03d6a54f621d720002-xx1T2L X-Barracuda-Envelope-From: JAxboe@fusionio.com Message-ID: <4D754146.1070206@fusionio.com> Date: Mon, 7 Mar 2011 21:34:14 +0100 From: Jens Axboe MIME-Version: 1.0 To: Vivek Goyal CC: "oleg@redhat.com" , "paulmck@linux.vnet.ibm.com" , linux kernel mailing list Subject: Re: [PATCH 0/2] blk-throttle: Couple of cleanup and fixes for limit update code References: <1298331770-20079-1-git-send-email-vgoyal@redhat.com> <20110307155006.GF9540@redhat.com> <4D753C79.4020800@fusionio.com> <20110307202917.GI9540@redhat.com> X-ASG-Orig-Subj: Re: [PATCH 0/2] blk-throttle: Couple of cleanup and fixes for limit update code In-Reply-To: <20110307202917.GI9540@redhat.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Barracuda-Connect: mail1.int.fusionio.com[10.101.1.21] X-Barracuda-Start-Time: 1299530056 X-Barracuda-URL: http://10.101.1.180:8000/cgi-mod/mark.cgi X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using per-user scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=9.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.2.57343 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1984 Lines: 51 On 2011-03-07 21:29, Vivek Goyal wrote: > On Mon, Mar 07, 2011 at 09:13:45PM +0100, Jens Axboe wrote: >> On 2011-03-07 16:50, Vivek Goyal wrote: >>> On Mon, Feb 21, 2011 at 06:42:48PM -0500, Vivek Goyal wrote: >>>> Hi Jens, >>>> >>>> Couple of throttle fixes seem to have fallen through cracks. >>>> >>>> https://lkml.org/lkml/2010/12/15/331 >>>> >>>> I am reposting it for inclusion. Please let me know if you have any concerns. >>>> Oleg and Paul acked the patch in the past so I am retaining their Reviewed-by: >>>> lines. >>>> >>> >>> Hi Jens, >>> >>> Can you please apply following patches for 2.6.39. These are good for fixing >>> couple of race conditions in block throttle code w.r.t limit updates. >>> Please let me know if you have concernes with these patches. >> >> I have applied them now. 2/2 is a nice cleanup. But it does not apply >> cleanly after the workqueue change we merged last week. I fixed it up >> for you, manually applied hunk #5 and added the below diff. Please >> inspect the end result. You should have rebased that patch. > > Sorry, this patch was posted before workqueue change last week. I should > have rebased and reposted it before pinging you again. Will take care of > it next time onwards. > >> >> Also note that you seem to have a double xchg() in there, also added >> from 2/2. > > Actually one xchg is tracking per group limit changes (tg) and one xchg() > it tracking overall limit change per queue (td), meaning if any of > the group on this queue has changed the limit or not. That avoids > traversal of list of all the groups if none of the group has changed > the limit. Irk, it's the tg and td looking too similar. It's indeed not a double xhcg(), sorry for the noise. -- Jens Axboe -- 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/