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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 5EA46C7618F for ; Fri, 26 Jul 2019 23:24:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1624020869 for ; Fri, 26 Jul 2019 23:24:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="W2KYODEs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726571AbfGZXYb (ORCPT ); Fri, 26 Jul 2019 19:24:31 -0400 Received: from mout.gmx.net ([212.227.15.15]:43089 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726167AbfGZXYa (ORCPT ); Fri, 26 Jul 2019 19:24:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1564183456; bh=SNvyN2iD5lBxulOqDqWeE6quPnedzolWrtHqY9gWVTI=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=W2KYODEsDUjgpdG1Uv00DgbmxSIj0F5ytidTc/b//MrB7r//5bfBzscaMdyOcSRVb X8GZVQPqhDLX6Ukf5XCazVKHbDQ2WfUNuFF9zV/eyV7LkiqrAGh+QhQjXEBKuMbkWh cQ0eOioy73IqVN/pd2ShG++lyiJD3YNrDWhb+M8U= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([54.250.245.166]) by mail.gmx.com (mrgmx001 [212.227.17.184]) with ESMTPSA (Nemesis) id 0LkfdE-1iRJjX2zm0-00aYRw; Sat, 27 Jul 2019 01:24:16 +0200 Subject: Re: qgroup: Don't trigger backref walk at delayed ref insert time (Re: Kernel traces) To: "Stephen R. van den Berg" Cc: Btrfs BTRFS References: <20181210120514.GA14828@cuci.nl> <20181211115226.GA20157@cuci.nl> <20181212072614.GA9188@cuci.nl> <20181228092036.GA30363@cuci.nl> <9b81647b-66c2-9870-161f-084b7d41af9c@gmx.com> <20190726163132.GA29895@cuci.nl> From: Qu Wenruo Openpgp: preference=signencrypt Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAVQEEwEIAD4CGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWCnQUJCWYC bgAKCRDCPZHzoSX+qAR8B/94VAsSNygx1C6dhb1u1Wp1Jr/lfO7QIOK/nf1PF0VpYjTQ2au8 ihf/RApTna31sVjBx3jzlmpy+lDoPdXwbI3Czx1PwDbdhAAjdRbvBmwM6cUWyqD+zjVm4RTG rFTPi3E7828YJ71Vpda2qghOYdnC45xCcjmHh8FwReLzsV2A6FtXsvd87bq6Iw2axOHVUax2 FGSbardMsHrya1dC2jF2R6n0uxaIc1bWGweYsq0LXvLcvjWH+zDgzYCUB0cfb+6Ib/ipSCYp 3i8BevMsTs62MOBmKz7til6Zdz0kkqDdSNOq8LgWGLOwUTqBh71+lqN2XBpTDu1eLZaNbxSI ilaVuQENBFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcga CbPEwhLj1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj /IrRUUka68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fN GSsRb+pKEKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0 q1eW4Jrv0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEv ABEBAAGJATwEGAEIACYWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWBrwIbDAUJA8JnAAAK CRDCPZHzoSX+qA3xB/4zS8zYh3Cbm3FllKz7+RKBw/ETBibFSKedQkbJzRlZhBc+XRwF61mi f0SXSdqKMbM1a98fEg8H5kV6GTo62BzvynVrf/FyT+zWbIVEuuZttMk2gWLIvbmWNyrQnzPl mnjK4AEvZGIt1pk+3+N/CMEfAZH5Aqnp0PaoytRZ/1vtMXNgMxlfNnb96giC3KMR6U0E+siA 4V7biIoyNoaN33t8m5FwEwd2FQDG9dAXWhG13zcm9gnk63BN3wyCQR+X5+jsfBaS4dvNzvQv h8Uq/YGjCoV1ofKYh3WKMY8avjq25nlrhzD/Nto9jHp8niwr21K//pXVA81R2qaXqGbql+zo Message-ID: <9c462f2e-9157-6bce-84f7-e70afa8bbe31@gmx.com> Date: Sat, 27 Jul 2019 07:24:12 +0800 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: <20190726163132.GA29895@cuci.nl> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="I3BlDjvx0ccCTSoxyn52SfboKeObgkibv" X-Provags-ID: V03:K1:i9NImdKOPh10o2JErB1w7n6rz+/N0wxYhUKgY/HQLKYObBZhQC2 jMK0sjTLB2UJqLfPJCxVJ61yGGmoid3wSW5wkoArgrUpk77DYT4O/+SShfSawRl9Bx/km9s XR0ggeeA8zLt1tVDFaxDcwisjSEwC8LAK3qTULWpEc4KemXor9XAsj2RkdXmOq1u1nzDDvK cODx0gwZ0emOu2J+MqW9A== X-UI-Out-Filterresults: notjunk:1;V03:K0:6q250u1KXPo=:7pyL8kLboE1vKDvSfLCw6I 6ueiIT5jnU97gKFdAKaUGyfRkvnepy+WsIwdh39diUZ44tEjn1748uuC1ObgZ8VDDxu0CjZ/Y 76Ezlak/a4iDIstcPLQ1ZSWN7fkJrlVWCjtMKl/EUADxsdPVjd2MxSty0HLsHj+UrnmM98nUY XvtoZTe5jwQHcMC49XwWlPHj5XWoN8eTLkNDedujtKuk9o5wsBzsWB4P0T7Myjd4lCRA3BG+9 LBvpo9vIvGh6ihsam0rkb95V4Or6HybXLvFqKN3C9MeV1kzGni1HCqu4pWvPREqNlxxRMknp9 z/JDK015RDvzR1VsHM0N3F1smszxJb+zgKQkHPlCsfoJVyBEqKrpFC8D3pfJnyY3U3INJk2rD yoaSYC9JJAesE8w43yNNc0H8gQzsbAhDVrJqNPV3yHDek1tlXSZY2Y8gOEO1sLGkcb7qN/sfD j/PXA2/cp66UFFaF5po9OfzExG7ckMtqfysWE3YYle3/A4h3HBLwnmY8/xfcVVGUkojaarOiM pgFC/R553XUfEbZslU7+NKrN9rGztxXb6h+/g6orGm5AO/s8lmJtTWW4JnHl5Tc5r7MiegcIj l/fKxoR8b7b4/8/P0G2+Idm2XYIfsOeW26wZLx11+sxQqRA/Vq1SJuAgucc9pot1YSmlufTxK kepzybDFYLJoizfE6iXTyyaa09Lp9SOMkZdg5VXngFmtlEGIfh4JJpph0f8mA+84iBtaxDfRh kqXg4dut7/67HzFNFY1tjXILRkVvaHhGZ2hLBE4tkfuOXNXQlx7iO9j2XG6VBm+gto3Y/xzMt I/BBy4nwlo8d8j9vftpqq4gwDq0P6gMQ+yR1DDvwKiYXBkEJzJy9KxI4cHmT11vgcFR8V32bm hPeEwkhIcIImgLrMKESp2t+hJhwJG+v2pgdAmgHI2z0njPAomcQk5RzhTIfZrpaIo3pOY3HFR 72H/ufnUrIUQGLsc83Rw/jQRpH8Kqmqd6Hp5cHhj7yFGq3EDiXfKxKlU5ZyJx0CvphLWw+K5Q pcNO5GbO933pqe9ZpiECMBRzbaqN1C+Kl7nt6KqRE03kCtrLIUwq77d3q5zOdo+pwNKdbbaWi FBFk6lO8GGw28E= Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --I3BlDjvx0ccCTSoxyn52SfboKeObgkibv Content-Type: multipart/mixed; boundary="WPFNyzHqdQYT31hntbIISagUCvhSyTLxv"; protected-headers="v1" From: Qu Wenruo To: "Stephen R. van den Berg" Cc: Btrfs BTRFS Message-ID: <9c462f2e-9157-6bce-84f7-e70afa8bbe31@gmx.com> Subject: Re: qgroup: Don't trigger backref walk at delayed ref insert time (Re: Kernel traces) References: <20181210120514.GA14828@cuci.nl> <20181211115226.GA20157@cuci.nl> <20181212072614.GA9188@cuci.nl> <20181228092036.GA30363@cuci.nl> <9b81647b-66c2-9870-161f-084b7d41af9c@gmx.com> <20190726163132.GA29895@cuci.nl> In-Reply-To: <20190726163132.GA29895@cuci.nl> --WPFNyzHqdQYT31hntbIISagUCvhSyTLxv Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2019/7/27 =E4=B8=8A=E5=8D=8812:31, Stephen R. van den Berg wrote: > Qu Wenruo wrote: >> It's caused by qgroup, and a dead lock on btrfs_drop_snapshot(). >=20 >> This is one of the easiest way to trigger an ABBA deadlock. >=20 >> Please either disable qgroup or apply this patch to solve it: >> https://patchwork.kernel.org/patch/10725371/ >=20 > Can anyone confirm that patch https://patchwork.kernel.org/patch/107253= 71/ > (qgroup: Don't trigger backref walk at delayed ref insert time) > is present in mainline Linux kernel v5.2.2 ? Upstream goes with a better solution: Fixes: 38e3eebff643 ("btrfs: honor path->skip_locking in backref code") Thanks, Qu >=20 > I seem to be getting a conflict on merging that patch with this kernel.= >=20 --WPFNyzHqdQYT31hntbIISagUCvhSyTLxv-- --I3BlDjvx0ccCTSoxyn52SfboKeObgkibv Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl07i5wACgkQwj2R86El /qj6Ugf9HLOS1rJj8tMpacwMEyQpQw/RZT40uRa8l9VQENgTz7tXvJovLuvHCN4C DhRU0hBGXYRPfA00ncwHuni8wl5LxSsjaIG44Xli7s557D4LTaP+qWEuuxpqPZKN mmmx0oBpSM7JY8ijdDCBjxPmGf+kSfP18q9Wy8ZBdC4s/BRPDqgok7pmA19dYT/v ChNH9s6Yd9GEKhv4z/O8tSRobx/Vcp+/YMzsMzRbQW9xPKK4ZvGMk+im2NuUv/bV Ee7rMIGb9gDnriwbSIj/dlMKhiSzDrlUjb2xDRK5LUZiYB9J3xJFumrf/jpPMsCD nUAOwbB/aS+5p5qbRNEytpkbt3tj+A== =xmLh -----END PGP SIGNATURE----- --I3BlDjvx0ccCTSoxyn52SfboKeObgkibv--