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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]:38426 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kAYjD-0005Ih-VK for qemu-devel@archiver.kernel.org; Tue, 25 Aug 2020 09:11:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43146) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kAYib-0004i2-AT for qemu-devel@nongnu.org; Tue, 25 Aug 2020 09:10:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:33148) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kAYiZ-0002Zp-J3 for qemu-devel@nongnu.org; Tue, 25 Aug 2020 09:10:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598361026; 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:autocrypt:autocrypt; 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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: <15cbc4e6-2a81-935f-ea26-5e98b80f40c2@redhat.com> Date: Tue, 25 Aug 2020 15:10:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200821141123.28538-7-vsementsov@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="yQv549sZ2bCGuBlGk5L8tJhoH4d5GuQSN" Received-SPF: pass client-ip=216.205.24.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/25 02:03:58 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -56 X-Spam_score: -5.7 X-Spam_bar: ----- X-Spam_report: (-5.7 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.958, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-2.602, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no 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, qemu-devel@nongnu.org, armbru@redhat.com, nsoffer@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) --yQv549sZ2bCGuBlGk5L8tJhoH4d5GuQSN Content-Type: multipart/mixed; boundary="zJk4bmZ5cKqhVca2jG6L5v4SRnsYQMRsH" --zJk4bmZ5cKqhVca2jG6L5v4SRnsYQMRsH Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 21.08.20 16:11, Vladimir Sementsov-Ogievskiy wrote: > Add flag to make serialising request no wait: if there are conflicting > requests, just return error immediately. It's will be used in upcoming > preallocate filter. >=20 > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > include/block/block.h | 9 ++++++++- > block/io.c | 11 ++++++++++- > 2 files changed, 18 insertions(+), 2 deletions(-) >=20 > diff --git a/include/block/block.h b/include/block/block.h > index b8f4e86e8d..877fda06a4 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -67,8 +67,15 @@ typedef enum { > * written to qiov parameter which may be NULL. > */ > BDRV_REQ_PREFETCH =3D 0x200, > + > + /* > + * If we need to wait for other requests, just fail immediately. Use= d > + * only together with BDRV_REQ_SERIALISING. > + */ > + BDRV_REQ_NO_WAIT =3D 0x400, > + > /* Mask of valid flags */ > - BDRV_REQ_MASK =3D 0x3ff, > + BDRV_REQ_MASK =3D 0x7ff, > } BdrvRequestFlags; > =20 > typedef struct BlockSizes { > diff --git a/block/io.c b/block/io.c > index dd28befb08..c93b1e98a3 100644 > --- a/block/io.c > +++ b/block/io.c > @@ -1912,9 +1912,18 @@ bdrv_co_write_req_prepare(BdrvChild *child, int64_= t offset, uint64_t bytes, > assert(!(bs->open_flags & BDRV_O_INACTIVE)); > assert((bs->open_flags & BDRV_O_NO_IO) =3D=3D 0); > assert(!(flags & ~BDRV_REQ_MASK)); > + assert(!((flags & BDRV_REQ_NO_WAIT) && !(flags & BDRV_REQ_SERIALISIN= G))); > =20 > if (flags & BDRV_REQ_SERIALISING) { > - bdrv_make_request_serialising(req, bdrv_get_cluster_size(bs)); > + QEMU_LOCK_GUARD(&bs->reqs_lock); > + > + tracked_request_set_serialising(req, bdrv_get_cluster_size(bs)); > + > + if ((flags & BDRV_REQ_NO_WAIT) && bdrv_find_conflicting_request(= req)) { bdrv_find_conflicting_request() will return NULL even if there are conflicting requests, but those have a non-NULL waiting_for. Is that something to consider? (I would like to think that will never have a real impact because then we must find some other conflicting request; but isn=E2=80=99t is possible = that we find an overlapping request that waits for another request with which it overlaps, but our request does not?) Max > + return -EBUSY; > + } > + > + bdrv_wait_serialising_requests_locked(req); > } else { > bdrv_wait_serialising_requests(req); > } >=20 --zJk4bmZ5cKqhVca2jG6L5v4SRnsYQMRsH-- --yQv549sZ2bCGuBlGk5L8tJhoH4d5GuQSN Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl9FDbYACgkQ9AfbAGHV z0A2hAf/RGEXk/+pVKVj4Gcdnp5YSZIZVYoFFMGLxVTmrTFr5U393OVLRhbAFzpa xQQ54Y0C/BxlyGB7Xw5dkEc1+Q4LUteN0o1I58in4EqQhTXIGVOp3YnLY2bWHOEV IGn710MNKY3Z8sAY5BBOHRY71OHtqpqLPE4f4VVnBrRE/UfpWZF68VlNB8KMAW5N y18FzuvpLfiMcREw88nOH5TUlmrxQyHO8552xP1A4pL3OJ32WomY2Zl4QPpStxmt 9i5eFtAsWZ6vVfvo+GVrBHZCOeDLIupwxhcOq4QLufpTir1ySEZ5UsaUx5FPHrLm k8W5HrXiit85gRDlZG5/2TNPOIJmVg== =FAhW -----END PGP SIGNATURE----- --yQv549sZ2bCGuBlGk5L8tJhoH4d5GuQSN--