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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BFC0C433DF for ; Thu, 14 May 2020 18:54:22 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49B9F2065F for ; Thu, 14 May 2020 18:54:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WH8NchuS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49B9F2065F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34912 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jZIzt-00048R-DH for qemu-devel@archiver.kernel.org; Thu, 14 May 2020 14:54:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51682) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jZIyL-0001bL-Ti for qemu-devel@nongnu.org; Thu, 14 May 2020 14:52:45 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:26892 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jZIyL-0008Q3-1b for qemu-devel@nongnu.org; Thu, 14 May 2020 14:52:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589482364; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cFHmAo/Ta9Am41+z7YYXNGdux6kJyGnK/Xf1wjEHH28=; b=WH8NchuSi2wB/bbPOxqvYWpLVJ8PZHhzmddQ2P+ZLfmzSdhi0hxMSuI5B1bOnhFxuTEbEJ 1ZYn1haGBUNqcFD6FV63izL1qcKZ5TVr3oY0VzEpo5zSs/B0Hz6jxG9RNCLh64sH4kfjtK RmB1+3gAv3Cg/rSS8EdPuxtXR6CvhGU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-137-HPAlWh3jNFuwmYk8sIHWIw-1; Thu, 14 May 2020 14:52:42 -0400 X-MC-Unique: HPAlWh3jNFuwmYk8sIHWIw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EA87D80183C; Thu, 14 May 2020 18:52:40 +0000 (UTC) Received: from [10.3.116.145] (ovpn-116-145.phx2.redhat.com [10.3.116.145]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 50B6746; Thu, 14 May 2020 18:52:37 +0000 (UTC) Subject: Re: [PATCH v2 4/5] migration/block-dirty-bitmap: fix bitmaps migration during mirror job To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20191219085106.22309-1-vsementsov@virtuozzo.com> <20191219085106.22309-5-vsementsov@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <2002b98a-d58a-017c-5014-02986f4e58e3@redhat.com> Date: Thu, 14 May 2020 13:52:36 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20191219085106.22309-5-vsementsov@virtuozzo.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=207.211.31.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/14 11:35:35 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fam@euphon.net, kwolf@redhat.com, quintela@redhat.com, qemu-devel@nongnu.org, dgilbert@redhat.com, stefanha@redhat.com, den@openvz.org, mreitz@redhat.com, jsnow@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 12/19/19 2:51 AM, Vladimir Sementsov-Ogievskiy wrote: > Important thing for bitmap migration is to select destination block > node to obtain the migrated bitmap. > > Prepatch, on source we use bdrv_get_device_or_node_name() to identify > the node, and on target we do bdrv_lookup_bs. > bdrv_get_device_or_node_name() returns blk name only for direct > children of blk. So, bitmaps of direct children of blks are migrated by > blk name and others - by node name. > > Libvirt currently is unprepared to bitmap migration by node-name, > node-names are mostly auto-generated. So actually only migration by blk > name works. It depends on whether -blockdev is in use. With -blockdev, libvirt should be supplying a node name everywhere, without, it is only device names. > > Now, consider classic libvirt migrations assisted by mirror block job: > mirror block job inserts filter, so our source is not a direct child of > blk, and bitmaps are migrated by node-names. And this just don't work. Does Max' work to improve seeing through filters fix this? > > Let's fix it by allowing use blk-name even if some implicit filters are > inserted. > > Note, that we possibly want to allow explicit filters skipping too, but > this is another story. > > Note2: we, of course, can't skip filters and use blk name to migrate > bitmaps in filtered node by blk name for this blk if these filters have > named bitmaps which should be migrated. > > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1652424 That bug has been marked CLOSED in the meantime, but it appears to be only because libvirt is now using -blockdev rather than the older drive, while the problem affects drive usage. > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > migration/block-dirty-bitmap.c | 39 +++++++++++++++++++++++++++++++++- > 1 file changed, 38 insertions(+), 1 deletion(-) > > Okay, after reading some more history on this project (the curse of coming up to speed after volunteering to become a co-maintainer), it looks like Max's idea replaces this patch altogether. How much of the rest of the series is still important? -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org