Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754814AbdCJEkb (ORCPT ); Thu, 9 Mar 2017 23:40:31 -0500 Received: from mail-pf0-f170.google.com ([209.85.192.170]:34553 "EHLO mail-pf0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753120AbdCJEk2 (ORCPT ); Thu, 9 Mar 2017 23:40:28 -0500 Subject: Re: [PATCH v2] blk: improve order of bio handling in generic_make_request() To: NeilBrown , Jack Wang References: <87h93blz6g.fsf@notabene.neil.brown.name> <71562c2c-97f4-9a0a-32ec-30e0702ca575@profitbricks.com> <87lgsjj9w8.fsf@notabene.neil.brown.name> <87r328j00i.fsf@notabene.neil.brown.name> <87d1dphhuy.fsf@notabene.neil.brown.name> <58be6551-4aa7-72ee-1616-a1545606d029@kernel.dk> Cc: LKML , Lars Ellenberg , Kent Overstreet , Pavel Machek , Mike Snitzer , Mikulas Patocka , linux-raid@vger.kernel.org, device-mapper development , linux-block@vger.kernel.org From: Jens Axboe Message-ID: <9af0f921-ad24-961e-085d-86c1973dbe8a@kernel.dk> Date: Thu, 9 Mar 2017 21:40:24 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <58be6551-4aa7-72ee-1616-a1545606d029@kernel.dk> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1077 Lines: 27 On 03/09/2017 09:38 PM, Jens Axboe wrote: > On 03/09/2017 09:32 PM, NeilBrown wrote: >> >> I started looking further at the improvements we can make once >> generic_make_request is fixed, and realised that I had missed an >> important detail in this patch. >> Several places test current->bio_list, and two actually edit the list. >> With this change, that cannot see the whole lists, so it could cause a >> regression. >> >> So I've revised the patch to make sure that the entire list of queued >> bios remains visible, and change the relevant code to look at both >> the new list and the old list. >> >> Following that there are some patches which make the rescuer thread >> optional, and then starts removing it from some easy-to-fix places. > > Neil, note that the v2 patch is already in Linus tree as of earlier > today. You need to rebase the series, and if we need fixups on > top of v2, then that should be done separately and with increased > urgency. Additionally, at least the first patch appears to be badly mangled. The formatting is screwed up. -- Jens Axboe