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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 35AB5C35657 for ; Fri, 21 Feb 2020 17:16:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1447D20722 for ; Fri, 21 Feb 2020 17:16:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727709AbgBURQh (ORCPT ); Fri, 21 Feb 2020 12:16:37 -0500 Received: from mx2.suse.de ([195.135.220.15]:41244 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726198AbgBURQh (ORCPT ); Fri, 21 Feb 2020 12:16:37 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 8C528AED6; Fri, 21 Feb 2020 17:16:35 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 133A0DA70E; Fri, 21 Feb 2020 18:16:17 +0100 (CET) Date: Fri, 21 Feb 2020 18:16:17 +0100 From: David Sterba To: Josef Bacik Cc: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH] btrfs: set update the uuid generation as soon as possible Message-ID: <20200221171617.GQ2902@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com References: <20200214202206.1642-1-josef@toxicpanda.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200214202206.1642-1-josef@toxicpanda.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Feb 14, 2020 at 03:22:06PM -0500, Josef Bacik wrote: > In my EIO stress testing I noticed I was getting forced to rescan the > uuid tree pretty often, which was weird. This is because my error > injection stuff would sometimes inject an error after log replay but > before we loaded the UUID tree. If log replay committed the transaction > it wouldn't have updated the uuid tree generation, but the tree was > valid and didn't change, so there's no reason to not update the > generation here. > > Fix this by setting the BTRFS_FS_UPDATE_UUID_TREE_GEN bit immediately > after reading all the fs roots if the uuid tree generation matches the > fs generation. Then any transaction commits that happen during mount > won't screw up our uuid tree state, forcing us to do needless uuid > rescans. > > Fixes: 70f801754728 ("Btrfs: check UUID tree during mount if required") > Signed-off-by: Josef Bacik Added to misc-next, thanks.