From patchwork Thu Jun 11 15:21:01 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Mahoney X-Patchwork-Id: 6589221 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 6F1E5C0020 for ; Thu, 11 Jun 2015 15:21:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 95AF02058A for ; Thu, 11 Jun 2015 15:21:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D1F32063F for ; Thu, 11 Jun 2015 15:21:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754246AbbFKPVQ (ORCPT ); Thu, 11 Jun 2015 11:21:16 -0400 Received: from cantor2.suse.de ([195.135.220.15]:60017 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751404AbbFKPVL (ORCPT ); Thu, 11 Jun 2015 11:21:11 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id D7185AD29 for ; Thu, 11 Jun 2015 15:21:09 +0000 (UTC) Received: by starscream.home.jeffm.io (Postfix, from userid 1000) id 30F9386D14; Thu, 11 Jun 2015 11:21:05 -0400 (EDT) From: jeffm@suse.com To: linux-btrfs@vger.kernel.org Cc: Jeff Mahoney Subject: [PATCH 3/4] btrfs: explictly delete unused block groups in close_ctree and ro-remount Date: Thu, 11 Jun 2015 11:21:01 -0400 Message-Id: <1434036062-21597-4-git-send-email-jeffm@suse.com> X-Mailer: git-send-email 1.8.4.5 In-Reply-To: <1434036062-21597-1-git-send-email-jeffm@suse.com> References: <1434036062-21597-1-git-send-email-jeffm@suse.com> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Jeff Mahoney The cleaner thread may already be sleeping by the time we enter close_ctree. If that's the case, we'll skip removing any unused block groups queued for removal, even during a normal umount. They'll be cleaned up automatically at next mount, but users expect a umount to be a clean synchronization point, especially when used on thin-provisioned storage with -odiscard. We also explicitly remove unused block groups in the ro-remount path for the same reason. Signed-off-by: Jeff Mahoney --- fs/btrfs/disk-io.c | 9 +++++++++ fs/btrfs/super.c | 11 +++++++++++ 2 files changed, 20 insertions(+) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 2ef9a4b..2e47fef 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3710,6 +3710,15 @@ void close_ctree(struct btrfs_root *root) cancel_work_sync(&fs_info->async_reclaim_work); if (!(fs_info->sb->s_flags & MS_RDONLY)) { + /* + * If the cleaner thread is stopped and there are + * block groups queued for removal, the deletion will be + * skipped when we quit the cleaner thread. + */ + mutex_lock(&root->fs_info->cleaner_mutex); + btrfs_delete_unused_bgs(root->fs_info); + mutex_unlock(&root->fs_info->cleaner_mutex); + ret = btrfs_commit_super(root); if (ret) btrfs_err(fs_info, "commit super ret %d", ret); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 9e66f5e..2ccd8d4 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1539,6 +1539,17 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data) sb->s_flags |= MS_RDONLY; + /* + * Setting MS_RDONLY will put the cleaner thread to + * sleep at the next loop if it's already active. + * If it's already asleep, we'll leave unused block + * groups on disk until we're mounted read-write again + * unless we clean them up here. + */ + mutex_lock(&root->fs_info->cleaner_mutex); + btrfs_delete_unused_bgs(fs_info); + mutex_unlock(&root->fs_info->cleaner_mutex); + btrfs_dev_replace_suspend_for_unmount(fs_info); btrfs_scrub_cancel(fs_info); btrfs_pause_balance(fs_info);