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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id B6E05C43217 for ; Tue, 3 May 2022 09:37:01 +0000 (UTC) Received: from localhost ([::1]:47816 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nloxo-00073x-Qt for qemu-devel@archiver.kernel.org; Tue, 03 May 2022 05:37:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45876) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nlovd-00066B-UH for qemu-devel@nongnu.org; Tue, 03 May 2022 05:34:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:52732) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nlovX-0003H8-Eb for qemu-devel@nongnu.org; Tue, 03 May 2022 05:34:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1651570478; 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: in-reply-to:in-reply-to:references:references; bh=9GgjTQE/kB+X69RPrFR/ptYt3I6b/XE2IknzZo3a6ow=; b=bVc7Vf0kYOECNtinwa1tBLBcm5UagQx+rxPrseDKPSb0XLEjrz6XVJ43F8KqHJJ3PsJVFZ Z/I1BHNUiCgQg6josNDABq57t0qAZWXV7YS7S47ApBPfuS71A2PA0u3X+X92v0ulrm3gOT ayCBug0wq2I+Jft5yFNjiM/OQVbWwxs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-246-1svikIo9MxSvslVVPaTDug-1; Tue, 03 May 2022 05:34:35 -0400 X-MC-Unique: 1svikIo9MxSvslVVPaTDug-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 38E5A802819; Tue, 3 May 2022 09:34:35 +0000 (UTC) Received: from redhat.com (unknown [10.39.193.201]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D825B40CFD29; Tue, 3 May 2022 09:34:33 +0000 (UTC) Date: Tue, 3 May 2022 11:34:32 +0200 From: Kevin Wolf To: Vladimir Sementsov-Ogievskiy Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, eblake@redhat.com, hreitz@redhat.com, v.sementsov-og@mail.ru, jsnow@redhat.com, vsementsov@openvz.org, nikita.lapshin@virtuozzo.com Subject: Re: [PATCH v3 3/3] block: simplify handling of try to merge different sized bitmaps Message-ID: References: <20220401100804.315728-1-vsementsov@openvz.org> <20220401100804.315728-4-vsementsov@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220401100804.315728-4-vsementsov@openvz.org> X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 01.04.2022 um 12:08 hat Vladimir Sementsov-Ogievskiy geschrieben: > We have too much logic to simply check that bitmaps are of the same > size. Let's just define that hbitmap_merge() and > bdrv_dirty_bitmap_merge_internal() require their argument bitmaps be of > same size, this simplifies things. > > Let's look through the callers: > > For backup_init_bcs_bitmap() we already assert that merge can't fail. > > In bdrv_reclaim_dirty_bitmap_locked() we gracefully handle the error > that can't happen: successor always has same size as its parent, drop > this logic. > > In bdrv_merge_dirty_bitmap() we already has assertion and separate > check. Make the check explicit and improve error message. > > Signed-off-by: Vladimir Sementsov-Ogievskiy > Reviewed-by: Nikita Lapshin Reviewed-by: Kevin Wolf