From nobody Wed Apr 16 12:21:31 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1544621477220488.6183659780719; Wed, 12 Dec 2018 05:31:17 -0800 (PST) Received: from localhost ([::1]:44910 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gX4bb-0004tN-Vk for importer@patchew.org; Wed, 12 Dec 2018 08:31:16 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46048) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gX4YY-0002Oj-0Y for qemu-devel@nongnu.org; Wed, 12 Dec 2018 08:28:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gX4YV-0000yr-Px for qemu-devel@nongnu.org; Wed, 12 Dec 2018 08:28:05 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50334) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gX4YN-0000oH-1I; Wed, 12 Dec 2018 08:27:55 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 21141307D850; Wed, 12 Dec 2018 13:27:54 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-117-245.ams2.redhat.com [10.36.117.245]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0EBB360F94; Wed, 12 Dec 2018 13:27:52 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Wed, 12 Dec 2018 14:26:59 +0100 Message-Id: <20181212132735.16080-6-kwolf@redhat.com> In-Reply-To: <20181212132735.16080-1-kwolf@redhat.com> References: <20181212132735.16080-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Wed, 12 Dec 2018 13:27:54 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 05/41] block/replication: drop extra synchronization X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" From: Vladimir Sementsov-Ogievskiy After commit f8d59dfb40 "block/backup: fix fleecing scheme: use serialized writes" fleecing (specifically reading from backup target, when backup source is in backing chain of backup target) is safe, because all backup-job writes to target are serialized. Therefore we don't need additional synchronization for these reads. Signed-off-by: Vladimir Sementsov-Ogievskiy Signed-off-by: Kevin Wolf --- block/replication.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/block/replication.c b/block/replication.c index 6349d6958e..0c2989d2cb 100644 --- a/block/replication.c +++ b/block/replication.c @@ -218,9 +218,6 @@ static coroutine_fn int replication_co_readv(BlockDrive= rState *bs, QEMUIOVector *qiov) { BDRVReplicationState *s =3D bs->opaque; - BdrvChild *child =3D s->secondary_disk; - BlockJob *job =3D NULL; - CowRequest req; int ret; =20 if (s->mode =3D=3D REPLICATION_MODE_PRIMARY) { @@ -233,28 +230,9 @@ static coroutine_fn int replication_co_readv(BlockDriv= erState *bs, return ret; } =20 - if (child && child->bs) { - job =3D child->bs->job; - } - - if (job) { - uint64_t remaining_bytes =3D remaining_sectors * BDRV_SECTOR_SIZE; - - backup_wait_for_overlapping_requests(child->bs->job, - sector_num * BDRV_SECTOR_SIZE, - remaining_bytes); - backup_cow_request_begin(&req, child->bs->job, - sector_num * BDRV_SECTOR_SIZE, - remaining_bytes); - ret =3D bdrv_co_preadv(bs->file, sector_num * BDRV_SECTOR_SIZE, - remaining_bytes, qiov, 0); - backup_cow_request_end(&req); - goto out; - } - ret =3D bdrv_co_preadv(bs->file, sector_num * BDRV_SECTOR_SIZE, remaining_sectors * BDRV_SECTOR_SIZE, qiov, 0); -out: + return replication_return_value(s, ret); } =20 --=20 2.19.2