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Thu, 23 May 2019 16:33:53 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x4NGXqfx006064; Thu, 23 May 2019 16:33:52 GMT Received: from nexus.ravello.local (/213.57.127.2) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 23 May 2019 16:33:52 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=oYQNiLLInCaatn1i0R555HgKyXewzttIoWAlCHlEROk=; b=LdOpi1frBI+L8AZKoF5GYP5VfXVkkfYaYma43L8v8/h+Yuh9BSCqYQ8jwz9O/p1aHKsk W3RoJwD7cipuLF3uxC2S2Z3JQ7gnIjrQpzmF3DJ9JP4gF0HZIvklBLMPJKXUl7+Anmx+ om8trZV607W2ROaci2WL00KWglhDRv+gsZ5w1QYJQqpSkFdSD78nFNvhMlhNhOrR5An4 zU8xBnsHY5oqYWAUVnh2PgDyku+vc8egkdiuqvGBP6T1K0beQMcbG9RafXEofA5fFbQ3 NoqnN/YWtXqpxIWaiaLLmVP/WgQjattuw95pBJaeYhmjGjEvLv26O6ixr5y7XEcaAh+S Jg== From: Sam Eiderman To: kwolf@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org, mreitz@redhat.com Date: Thu, 23 May 2019 19:33:35 +0300 Message-Id: <20190523163337.4497-2-shmuel.eiderman@oracle.com> X-Mailer: git-send-email 2.13.3 In-Reply-To: <20190523163337.4497-1-shmuel.eiderman@oracle.com> References: <20190523163337.4497-1-shmuel.eiderman@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=926 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=955 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 156.151.31.85 Subject: [Qemu-devel] [PATCH v5 1/3] qemu-img: rebase: Reuse parent BlockDriverState 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: eyal.moscovici@oracle.com, arbel.moshe@oracle.com, liran.alon@oracle.com, shmuel.eiderman@oracle.com, sagi.amit@oracle.com, karl.heubaum@oracle.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" In safe mode we open the entire chain, including the parent backing file of the rebased file. Do not open a new BlockBackend for the parent backing file, which saves opening the rest of the chain twice, which for long chains saves many "pricy" bdrv_open() calls. Permissions for blk_new() were copied from blk_new_open() when flags =3D 0. Reviewed-by: Karl Heubaum Reviewed-by: Eyal Moscovici Signed-off-by: Sagi Amit Co-developed-by: Sagi Amit Signed-off-by: Sam Eiderman --- qemu-img.c | 29 +++++++++-------------------- 1 file changed, 9 insertions(+), 20 deletions(-) diff --git a/qemu-img.c b/qemu-img.c index 28fba1e7a7..9bd0bb1e47 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -3309,29 +3309,18 @@ static int img_rebase(int argc, char **argv) =20 /* For safe rebasing we need to compare old and new backing file */ if (!unsafe) { - char backing_name[PATH_MAX]; QDict *options =3D NULL; + BlockDriverState *base_bs =3D backing_bs(bs); =20 - if (bs->backing) { - if (bs->backing_format[0] !=3D '\0') { - options =3D qdict_new(); - qdict_put_str(options, "driver", bs->backing_format); - } - - if (force_share) { - if (!options) { - options =3D qdict_new(); - } - qdict_put_bool(options, BDRV_OPT_FORCE_SHARE, true); - } - bdrv_get_backing_filename(bs, backing_name, sizeof(backing_nam= e)); - blk_old_backing =3D blk_new_open(backing_name, NULL, - options, src_flags, &local_err); - if (!blk_old_backing) { + if (base_bs) { + blk_old_backing =3D blk_new(BLK_PERM_CONSISTENT_READ, + BLK_PERM_ALL); + ret =3D blk_insert_bs(blk_old_backing, base_bs, + &local_err); + if (ret < 0) { error_reportf_err(local_err, - "Could not open old backing file '%s': ", - backing_name); - ret =3D -1; + "Could not reuse old backing file '%s': = ", + base_bs->filename); goto out; } } else { --=20 2.13.3 From nobody Sun May 5 06:41:59 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=oracle.com ARC-Seal: i=1; a=rsa-sha256; t=1558629359; cv=none; d=zoho.com; s=zohoarc; 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Thu, 23 May 2019 16:33:55 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4NGW71A182570; Thu, 23 May 2019 16:33:55 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2smsh2bvq5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 23 May 2019 16:33:55 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x4NGXtfi006082; Thu, 23 May 2019 16:33:55 GMT Received: from nexus.ravello.local (/213.57.127.2) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 23 May 2019 16:33:54 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=ud4KqU+M+aj77AvMEO2QAvfX1xgBXAKGcMA9RsIp7Vc=; b=TMJiLS4eKhN+th8Mv60ow4GySI/ZOM3kdZZTdJBtVIIbWwpOmD0NjzRhQ4bhx2nEYHK0 UwZwrsGOozMhnlcfmosKb2y9U+N6OXhi25PNdRKptmJKlbKRhfOUf4ePpwQL6izFXE4A O7uYk1zUK+pqoaHpLRlEf2qKHYAMflsa5NSCpWGLhKMZuIk5MfvH4l3aM3C4JjOqvsoO 8W2+dNQmU0BJoCxXbgRt6nuyGUbDAqS738VqsaO7i8QBLBQQnRQM3ZArLsUhIFya8E+H j1LO9DMhFSZYjIQkcgbvBf09W09zK58QeGBleKI2cpYw7pGchHEmr6+d9IH/Qrmn/25n eA== From: Sam Eiderman To: kwolf@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org, mreitz@redhat.com Date: Thu, 23 May 2019 19:33:36 +0300 Message-Id: <20190523163337.4497-3-shmuel.eiderman@oracle.com> X-Mailer: git-send-email 2.13.3 In-Reply-To: <20190523163337.4497-1-shmuel.eiderman@oracle.com> References: <20190523163337.4497-1-shmuel.eiderman@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=959 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=997 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 141.146.126.79 Subject: [Qemu-devel] [PATCH v5 2/3] qemu-img: rebase: Reduce reads on in-chain rebase 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: eyal.moscovici@oracle.com, arbel.moshe@oracle.com, liran.alon@oracle.com, shmuel.eiderman@oracle.com, sagi.amit@oracle.com, karl.heubaum@oracle.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" In the following case: (base) A <- B <- C (tip) when running: qemu-img rebase -b A C QEMU would read all sectors not allocated in the file being rebased (C) and compare them to the new base image (A), regardless of whether they were changed or even allocated anywhere along the chain between the new base and the top image (B). This causes many unneeded reads when rebasing an image which represents a small diff of a large disk, as it would read most of the disk's sectors. Instead, use bdrv_is_allocated_above() to reduce the number of unnecessary reads. Reviewed-by: Karl Heubaum Signed-off-by: Sam Eiderman Signed-off-by: Eyal Moscovici --- qemu-img.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/qemu-img.c b/qemu-img.c index 9bd0bb1e47..2d96a491e2 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -3164,7 +3164,7 @@ static int img_rebase(int argc, char **argv) BlockBackend *blk =3D NULL, *blk_old_backing =3D NULL, *blk_new_backin= g =3D NULL; uint8_t *buf_old =3D NULL; uint8_t *buf_new =3D NULL; - BlockDriverState *bs =3D NULL; + BlockDriverState *bs =3D NULL, *prefix_chain_bs =3D NULL; char *filename; const char *fmt, *cache, *src_cache, *out_basefmt, *out_baseimg; int c, flags, src_flags, ret; @@ -3353,6 +3353,12 @@ static int img_rebase(int argc, char **argv) goto out; } =20 + /* + * Find out whether we rebase an image on top of a previous im= age + * in its chain. + */ + prefix_chain_bs =3D bdrv_find_backing_image(bs, out_real_path); + blk_new_backing =3D blk_new_open(out_real_path, NULL, options, src_flags, &local_err); g_free(out_real_path); @@ -3437,6 +3443,23 @@ static int img_rebase(int argc, char **argv) continue; } =20 + if (prefix_chain_bs) { + /* + * If cluster wasn't changed since prefix_chain, we don't = need + * to take action + */ + ret =3D bdrv_is_allocated_above(backing_bs(bs), prefix_cha= in_bs, + offset, n, &n); + if (ret < 0) { + error_report("error while reading image metadata: %s", + strerror(-ret)); + goto out; + } + if (!ret) { + continue; + } + } + /* * Read old and new backing file and take into consideration t= hat * backing files may be smaller than the COW image. --=20 2.13.3 From nobody Sun May 5 06:41:59 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; 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Thu, 23 May 2019 16:33:59 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4NGXaab167116; Thu, 23 May 2019 16:33:58 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 2smsgtbr26-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 23 May 2019 16:33:58 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x4NGXvrl029859; Thu, 23 May 2019 16:33:57 GMT Received: from nexus.ravello.local (/213.57.127.2) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 23 May 2019 16:33:57 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=fCJW25pGZJldWdnaL5qJqcdTdxQGjj4LeEDDaJvRWwc=; b=GC6MIp7MZxBbAuoFxZubcT7yrCF8WkiAooTqdr8YkmCYHyeSGguUDnnDK/cnwK6RWUh0 vWG9Vm+HuRSZGPX7wFFqgSDU6oeYg921/nprdTux5aE3oMZ3ugS8sYpskZ4mlRX3j9Wj 4kNBEiOs4XrXozHyKArh23FR5CeB43JY2q27Qgm9CO/FTup62luUuYcyxjRuqPwvlonM eT4aXCrImlCxIzK182QfmrVPD169UJCDATQWdXrMXPv8LELAf0SZpWiGYV+bCC+m9Z/j YLuqwau9MV/HO46O7kJuEsFSpp/V2rtNebFk/EQhkJT4KkrMc5XKMQvNId9bPMhBm6Bl IA== From: Sam Eiderman To: kwolf@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org, mreitz@redhat.com Date: Thu, 23 May 2019 19:33:37 +0300 Message-Id: <20190523163337.4497-4-shmuel.eiderman@oracle.com> X-Mailer: git-send-email 2.13.3 In-Reply-To: <20190523163337.4497-1-shmuel.eiderman@oracle.com> References: <20190523163337.4497-1-shmuel.eiderman@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9265 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905230112 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 156.151.31.85 Subject: [Qemu-devel] [PATCH v5 3/3] qemu-img: rebase: Reuse in-chain BlockDriverState 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: eyal.moscovici@oracle.com, arbel.moshe@oracle.com, liran.alon@oracle.com, shmuel.eiderman@oracle.com, sagi.amit@oracle.com, karl.heubaum@oracle.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" If a chain was detected, don't open a new BlockBackend from the target backing file which will create a new BlockDriverState. Instead, create an empty BlockBackend and attach the already open BlockDriverState. Permissions for blk_new() were copied from blk_new_open() when flags =3D 0. Reviewed-by: Karl Heubaum Reviewed-by: Eyal Moscovici Signed-off-by: Sagi Amit Co-developed-by: Sagi Amit Signed-off-by: Sam Eiderman --- qemu-img.c | 33 +++++++++++++++++++++++---------- 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/qemu-img.c b/qemu-img.c index 2d96a491e2..b0535919b1 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -3358,16 +3358,29 @@ static int img_rebase(int argc, char **argv) * in its chain. */ prefix_chain_bs =3D bdrv_find_backing_image(bs, out_real_path); - - blk_new_backing =3D blk_new_open(out_real_path, NULL, - options, src_flags, &local_err); - g_free(out_real_path); - if (!blk_new_backing) { - error_reportf_err(local_err, - "Could not open new backing file '%s': ", - out_baseimg); - ret =3D -1; - goto out; + if (prefix_chain_bs) { + g_free(out_real_path); + blk_new_backing =3D blk_new(BLK_PERM_CONSISTENT_READ, + BLK_PERM_ALL); + ret =3D blk_insert_bs(blk_new_backing, prefix_chain_bs, + &local_err); + if (ret < 0) { + error_reportf_err(local_err, + "Could not reuse backing file '%s': = ", + out_baseimg); + goto out; + } + } else { + blk_new_backing =3D blk_new_open(out_real_path, NULL, + options, src_flags, &local_= err); + g_free(out_real_path); + if (!blk_new_backing) { + error_reportf_err(local_err, + "Could not open new backing file '%s= ': ", + out_baseimg); + ret =3D -1; + goto out; + } } } } --=20 2.13.3