From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05CEBE9413E for ; Sat, 7 Oct 2023 02:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234078AbjJGClK (ORCPT ); Fri, 6 Oct 2023 22:41:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233755AbjJGClI (ORCPT ); Fri, 6 Oct 2023 22:41:08 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1337CBD; Fri, 6 Oct 2023 19:41:07 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BFD2C433C9; Sat, 7 Oct 2023 02:41:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696646466; bh=bwGFUBVwK4SPl5rUi0AHrK68P2vjEQfazBcMlXR+RaE=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=Cc9BmNrUYE8AeM1xNtAiR2C/DMgquJeOU1TfGVTWdiIW+2YakX18Dz4i0I06K0yUN rxxvnMdzitm6jKkR47hAfHfhNvmg/OdFfhrXU2rQenKRGEmgpJJMgMuKhiPtN+NJuh EsnJDhrfsk2Rsd+/f6Vumr20boJdghkx71XfMxlwjFV4kkFfJ/L/lhMVDpx5lUPjJ9 yiDSokDJ9fMrRnoGTYkhvIqVTDaDZa5lEnsZtESzdd8tgSYEzSAr6c4wvUh+qHkQDw iM41xZ5gRnb/KlE9gHeXf+2xMI6Oo9D3iRGgUs6yDfzqpO9ZP7lQINxaa5ZkDbOwnA mS05KERFyeK1g== Received: by mail-lf1-f53.google.com with SMTP id 2adb3069b0e04-504427aae4fso4720054e87.1; Fri, 06 Oct 2023 19:41:06 -0700 (PDT) X-Gm-Message-State: AOJu0YzouflLaTFxi+fyAHznnn1zXuBmObOJQpFQMtilsU09qh+8PM44 CUo/u5ERY8vyhQWjy5OBWDUTMpLL1lgVckTf1dc= X-Google-Smtp-Source: AGHT+IFZKXFMDdbJlrwzbWL763LgpyNh7kR9JWexcBVJPWIm2fnTDvq0yf/QIAKmPc6vXoFQVrJuE1yWYhbC0z4c0N4= X-Received: by 2002:a05:6512:3995:b0:4f8:586a:d6ca with SMTP id j21-20020a056512399500b004f8586ad6camr4814291lfu.9.1696646464789; Fri, 06 Oct 2023 19:41:04 -0700 (PDT) MIME-Version: 1.0 References: <20230928061543.1845742-1-yukuai1@huaweicloud.com> In-Reply-To: From: Song Liu Date: Fri, 6 Oct 2023 19:40:52 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH -next v3 00/25] md: synchronize io with array reconfiguration To: Yu Kuai Cc: xni@redhat.com, agk@redhat.com, snitzer@kernel.org, dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, "yukuai (C)" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On Fri, Oct 6, 2023 at 7:32=E2=80=AFPM Yu Kuai wr= ote: > > Hi, > > =E5=9C=A8 2023/10/05 11:55, Song Liu =E5=86=99=E9=81=93: > > On Wed, Oct 4, 2023 at 8:42=E2=80=AFPM Yu Kuai wrote: > >> > >> Hi, > >> > >> =E5=9C=A8 2023/09/29 3:15, Song Liu =E5=86=99=E9=81=93: > >>> Hi Kuai, > >>> > >>> Thanks for the patchset! > >>> > >>> A few high level questions/suggestions: > >> > >> Thanks a lot for these! > >>> > >>> 1. This is a big change that needs a lot of explanation. While you ma= naged to > >>> keep each patch relatively small (great job btw), it is not very clea= r why we > >>> need these changes. Specifically, we are adding a new mutex, it is wo= rth > >>> mentioning why we cannot achieve the same goal without it. Please add > >>> more information in the cover letter. We will put part of the cover l= etter in > >>> the merge commit. > >> > >> Yeah, I realize that I explain too little. I will add background and > >> design. > >>> > Can you take a look about this new cover letter? I don't have time right now to look into all the details, but it looks great at first glance. We can still edit it a little bit when applying the patchset, but that may not be necessary. Thanks, Song > > ##### Backgroud > > Our testers started to test raid10 last year, and we found that there > are lots of problem in the following test scenario: > > - add or remove disks to the array > - issue io to the array