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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 B1A09C4740A for ; Mon, 9 Sep 2019 13:46:04 +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 852FB20828 for ; Mon, 9 Sep 2019 13:46:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 852FB20828 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]:56822 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7JzX-0003Xl-N2 for qemu-devel@archiver.kernel.org; Mon, 09 Sep 2019 09:46:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33206) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7Jyf-0002uL-DU for qemu-devel@nongnu.org; Mon, 09 Sep 2019 09:45:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i7Jye-0008As-02 for qemu-devel@nongnu.org; Mon, 09 Sep 2019 09:45:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52192) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i7JyZ-00087Y-On; Mon, 09 Sep 2019 09:45:03 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1C0A78DCF81; Mon, 9 Sep 2019 13:45:03 +0000 (UTC) Received: from dresden.str.redhat.com (ovpn-116-179.ams2.redhat.com [10.36.116.179]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E15606012A; Mon, 9 Sep 2019 13:44:56 +0000 (UTC) To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20190830161228.54238-1-vsementsov@virtuozzo.com> <20190830161228.54238-15-vsementsov@virtuozzo.com> From: Max Reitz Openpgp: preference=signencrypt Autocrypt: addr=mreitz@redhat.com; prefer-encrypt=mutual; keydata= mQENBFXOJlcBCADEyyhOTsoa/2ujoTRAJj4MKA21dkxxELVj3cuILpLTmtachWj7QW+TVG8U /PsMCFbpwsQR7oEy8eHHZwuGQsNpEtNC2G/L8Yka0BIBzv7dEgrPzIu+W3anZXQW4702+uES U29G8TP/NGfXRRHGlbBIH9KNUnOSUD2vRtpOLXkWsV5CN6vQFYgQfFvmp5ZpPeUe6xNplu8V mcTw8OSEDW/ZnxJc8TekCKZSpdzYoxfzjm7xGmZqB18VFwgJZlIibt1HE0EB4w5GsD7x5ekh awIe3RwoZgZDLQMdOitJ1tUc8aqaxvgA4tz6J6st8D8pS//m1gAoYJWGwwIVj1DjTYLtABEB AAG0HU1heCBSZWl0eiA8bXJlaXR6QHJlZGhhdC5jb20+iQFTBBMBCAA9AhsDBQkSzAMABQsJ CAcCBhUICQoLAgQWAgMBAh4BAheABQJVzie5FRhoa3A6Ly9rZXlzLmdudXBnLm5ldAAKCRD0 B9sAYdXPQDcIB/9uNkbYEex1rHKz3mr12uxYMwLOOFY9fstP5aoVJQ1nWQVB6m2cfKGdcRe1 2/nFaHSNAzT0NnKz2MjhZVmcrpyd2Gp2QyISCfb1FbT82GMtXFj1wiHmPb3CixYmWGQUUh+I AvUqsevLA+WihgBUyaJq/vuDVM1/K9Un+w+Tz5vpeMidlIsTYhcsMhn0L9wlCjoucljvbDy/ 8C9L2DUdgi3XTa0ORKeflUhdL4gucWoAMrKX2nmPjBMKLgU7WLBc8AtV+84b9OWFML6NEyo4 4cP7cM/07VlJK53pqNg5cHtnWwjHcbpGkQvx6RUx6F1My3y52vM24rNUA3+ligVEgPYBuQEN BFXOJlcBCADAmcVUNTWT6yLWQHvxZ0o47KCP8OcLqD+67T0RCe6d0LP8GsWtrJdeDIQk+T+F xO7DolQPS6iQ6Ak2/lJaPX8L0BkEAiMuLCKFU6Bn3lFOkrQeKp3u05wCSV1iKnhg0UPji9V2 W5eNfy8F4ZQHpeGUGy+liGXlxqkeRVhLyevUqfU0WgNqAJpfhHSGpBgihUupmyUg7lfUPeRM DzAN1pIqoFuxnN+BRHdAecpsLcbR8sQddXmDg9BpSKozO/JyBmaS1RlquI8HERQoe6EynJhd 64aICHDfj61rp+/0jTIcevxIIAzW70IadoS/y3DVIkuhncgDBvGbF3aBtjrJVP+5ABEBAAGJ ASUEGAEIAA8FAlXOJlcCGwwFCRLMAwAACgkQ9AfbAGHVz0CbFwf9F/PXxQR9i4N0iipISYjU sxVdjJOM2TMut+ZZcQ6NSMvhZ0ogQxJ+iEQ5OjnIputKvPVd5U7WRh+4lF1lB/NQGrGZQ1ic alkj6ocscQyFwfib+xIe9w8TG1CVGkII7+TbS5pXHRxZH1niaRpoi/hYtgzkuOPp35jJyqT/ /ELbqQTDAWcqtJhzxKLE/ugcOMK520dJDeb6x2xVES+S5LXby0D4juZlvUj+1fwZu+7Io5+B bkhSVPb/QdOVTpnz7zWNyNw+OONo1aBUKkhq2UIByYXgORPFnbfMY7QWHcjpBVw9MgC4tGeF R4bv+1nAMMxKmb5VvQCExr0eFhJUAHAhVg== Message-ID: Date: Mon, 9 Sep 2019 15:44:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190830161228.54238-15-vsementsov@virtuozzo.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="rWvRkZYIxatezMNp0p7zUr93AIYGiZ7Kp" X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.69]); Mon, 09 Sep 2019 13:45:03 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v10 14/14] block/backup: use backup-top instead of write notifiers 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, wencongyang2@huawei.com, xiechanglong.d@gmail.com, qemu-devel@nongnu.org, armbru@redhat.com, jsnow@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --rWvRkZYIxatezMNp0p7zUr93AIYGiZ7Kp Content-Type: multipart/mixed; boundary="gstlI6XGLrTZLGyvMIqVLd7dTgU7UXNAr"; protected-headers="v1" From: Max Reitz To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, eblake@redhat.com, armbru@redhat.com, xiechanglong.d@gmail.com, wencongyang2@huawei.com, fam@euphon.net, stefanha@redhat.com, jsnow@redhat.com, kwolf@redhat.com, den@openvz.org Message-ID: Subject: Re: [PATCH v10 14/14] block/backup: use backup-top instead of write notifiers References: <20190830161228.54238-1-vsementsov@virtuozzo.com> <20190830161228.54238-15-vsementsov@virtuozzo.com> In-Reply-To: <20190830161228.54238-15-vsementsov@virtuozzo.com> --gstlI6XGLrTZLGyvMIqVLd7dTgU7UXNAr Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 30.08.19 18:12, Vladimir Sementsov-Ogievskiy wrote: > Drop write notifiers and use filter node instead. >=20 > =3D Changes =3D >=20 > 1. Add filter-node-name argument for backup qmp api. We have to do it > in this commit, as 257 needs to be fixed. >=20 > 2. There are no more write notifiers here, so is_write_notifier > parameter is dropped from block-copy paths. >=20 > 3. Intersecting requests handling changed, now synchronization between > backup-top, backup and guest writes are all done in block/block-copy.c > and works as follows: >=20 > On copy operation, we work only with dirty areas. If bits are dirty it > means that there are no requests intersecting with this area. We clear > dirty bits and take bdrv range lock (bdrv_co_try_lock) on this area to > prevent further operations from interaction with guest (only with > guest, as neither backup nor backup-top will touch non-dirty area). If > copy-operation failed we set dirty bits back together with releasing > the lock. >=20 > The actual difference with old scheme is that on guest writes we > don't lock the whole region but only dirty-parts, and to be more > precise: only dirty-part we are currently operate on. In old scheme > guest write to non-dirty area (which may be safely ignored by backup) > may wait for intersecting request, touching some other area which is > dirty. >=20 > 4. To sync with in-flight requests at job finish we now have drained > removing of the filter, we don't need rw-lock. >=20 > =3D Notes =3D >=20 > Note the consequence of three objects appearing: backup-top, backup job= > and block-copy-state: >=20 > 1. We want to insert backup-top before job creation, to behave similar > with mirror and commit, where job is started upon filter. >=20 > 2. We also have to create block-copy-state after filter injection, as > we don't want its source child be replaced by filter. Instead we want > to keep BCS.source to be real source node, as we want to use > bdrv_co_try_lock in CBW operations and it can't be used on filter, as > on filter we already have in-flight (write) request from upper layer. >=20 > So, we firstly create inject backup-top, then create job and BCS. BCS > is the latest just to not create extra variable for it. Finally we set > bcs for backup-top filter. >=20 > =3D Iotest changes =3D >=20 > 56: op-blocker doesn't shoot now, as we set it on source, but then > check on filter, when trying to start second backup. > To keep the test we instead can catch another collision: both jobs will= > get 'drive0' job-id, as job-id parameter is unspecified. To prevent > interleaving with file-posix locks (as they are dependent on config) > let's use another target for second backup. >=20 > Also, it's obvious now that we'd like to drop this op-blocker at all > and add a test-case for two backups from one node (to different > destinations) actually works. But not in these series. >=20 > 257: The test wants to emulate guest write during backup. They should > go to filter node, not to original source node, of course. Therefore we= > need to specify filter node name and use it. >=20 > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > qapi/block-core.json | 8 +- > include/block/block-copy.h | 10 +- > include/block/block_int.h | 1 + > block/backup-top.c | 14 +- > block/backup.c | 113 +++----------- > block/block-copy.c | 45 ++++-- > block/replication.c | 2 +- > blockdev.c | 1 + > tests/qemu-iotests/056 | 8 +- > tests/qemu-iotests/257 | 7 +- > tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------= > 11 files changed, 238 insertions(+), 277 deletions(-) Reviewed-by: Max Reitz --gstlI6XGLrTZLGyvMIqVLd7dTgU7UXNAr-- --rWvRkZYIxatezMNp0p7zUr93AIYGiZ7Kp Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl12V1YACgkQ9AfbAGHV z0DfkAf/bEyIDXBZUXxRzWhNKnkKOmbrJeNmlyMD2IyUdJxFSP3/cwtqgM69R3SR mlYcRR+WGqsdVQT4VjQBGmva/yw1AxyS7NH2rptRq2MqChRLpoJ5P8Eis/FQjirb p2xt1nvkksZZhCOzdK4NOpd0LuPkLlgcKtGGTJ0vRle1FQQtdP31YqWiYAS1ETMI 9liAmLC9utWzu+0oMJ+bTfB6JF9WqOaUB1G6Q/uOVDV4tNXEuqc9gQRkXt9OHKdc kQCoIE4L4rnNaH9s9GBV13t8HS9hd7nTVB8srT9TBY+D336kXCvSb/gbhbafcFd0 Nhlr/f3CUl0i/0sRsWkd4x87XJjGIg== =0MZM -----END PGP SIGNATURE----- --rWvRkZYIxatezMNp0p7zUr93AIYGiZ7Kp--