From patchwork Wed Nov 21 19:09:22 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 10693103 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8B3D513BF for ; Wed, 21 Nov 2018 19:09:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7898B2C2B9 for ; Wed, 21 Nov 2018 19:09:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6CD5F2C2BE; Wed, 21 Nov 2018 19:09:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C38C82C2B9 for ; Wed, 21 Nov 2018 19:09:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388453AbeKVFpD (ORCPT ); Thu, 22 Nov 2018 00:45:03 -0500 Received: from mail-yw1-f65.google.com ([209.85.161.65]:35025 "EHLO mail-yw1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388448AbeKVFpC (ORCPT ); Thu, 22 Nov 2018 00:45:02 -0500 Received: by mail-yw1-f65.google.com with SMTP id h32so2692825ywk.2 for ; Wed, 21 Nov 2018 11:09:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=from:to:subject:date:message-id:in-reply-to:references; bh=9bPPV7NkfBrLK2PcGSqEp/CCsUF5YqP0GCJnqYp4fm4=; b=09f8JORQ1fdvgzOyHKE3iutQoLLGjGAddTqS0xxmaOtLmuDp9S2ShwN5334ybjlHed YcyxgSNR1Y86mjWTmaCKzqj58+dIeSF8SPDrCfXFAXoPeIzp2kw06dZGpvOQg41m/15p DpYxXZQBv5Ovr1Qgq2/3Ja1XkFBPzUdB1snW+XgctKF0MBALET8RZOyL23XZqv8nA0pn CwwZbr9egQwbzJbaBxG+Xfhz1QMh+WCdPFPmdTkiP1v+DATEFmU/f/YW3GMZh1YJzWAu /X+Veo78pi1bgu9oBLovcx5sfu+/nVDghKLSkFzdlrjy3aRgJY/v0l2qoSAKVEQHXN8f pVHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=9bPPV7NkfBrLK2PcGSqEp/CCsUF5YqP0GCJnqYp4fm4=; b=ptz6tBY+Kd7HKOHiKvkHynS7X0oXi3Hkr/o0VrHUYdZdmBcXmQEHpY7FMvB6zAq9qj Kf1M+bPP7ehLKpJacJq/MZXPgBtAjmw71zSsiR+9p1IgxdFpjHc4+z/m7aeDpLnxjsoU qMW1dJ1fTe1uxdUAhosvwB3LZWMz3EfbU64+NlNti3Y1wI3PqzCQ7CWxxVncMwUhIlg0 il/Ksc2jdzu+gB2Xl7IKM3F+m7iIKVdwOjiuEzlCQdrP/QUIFyTYyYVVJwIwlQMFtBEO AI4RSY6tpDywFqGvWV9y6L22pYLVEI389kbePcowRB7QY/oV08BJp4Na1BmTQE5hCSJH 0gTg== X-Gm-Message-State: AGRZ1gKlMkEol9rdrjnz9nYbPq2EwVQJurjjWryQLbDr92nKuJnfyB6g 4ss7q+9KNsAx65zHOS/43oqqU6hwMPk= X-Google-Smtp-Source: AJdET5e42G+lx73wayv1pkxvDWCdF/LpCWy1pUsWqE5OrGUCfceLG13wXo537BitaTxa30U5/e7fJQ== X-Received: by 2002:a0d:d84c:: with SMTP id a73mr7955748ywe.184.1542827369163; Wed, 21 Nov 2018 11:09:29 -0800 (PST) Received: from localhost ([107.15.81.208]) by smtp.gmail.com with ESMTPSA id c127sm7279933ywb.67.2018.11.21.11.09.28 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 21 Nov 2018 11:09:28 -0800 (PST) From: Josef Bacik To: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 3/3] btrfs: replace cleaner_delayed_iput_mutex with a waitqueue Date: Wed, 21 Nov 2018 14:09:22 -0500 Message-Id: <20181121190922.25038-4-josef@toxicpanda.com> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20181121190922.25038-1-josef@toxicpanda.com> References: <20181121190922.25038-1-josef@toxicpanda.com> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The throttle path doesn't take cleaner_delayed_iput_mutex, which means we could think we're done flushing iputs in the data space reservation path when we could have a throttler doing an iput. There's no real reason to serialize the delayed iput flushing, so instead of taking the cleaner_delayed_iput_mutex whenever we flush the delayed iputs just replace it with an atomic counter and a waitqueue. This removes the short (or long depending on how big the inode is) window where we think there are no more pending iputs when there really are some. Signed-off-by: Josef Bacik --- fs/btrfs/ctree.h | 4 +++- fs/btrfs/disk-io.c | 5 ++--- fs/btrfs/extent-tree.c | 9 +++++---- fs/btrfs/inode.c | 21 +++++++++++++++++++++ 4 files changed, 31 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 709de7471d86..a835fe7076eb 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -912,7 +912,8 @@ struct btrfs_fs_info { spinlock_t delayed_iput_lock; struct list_head delayed_iputs; - struct mutex cleaner_delayed_iput_mutex; + atomic_t nr_delayed_iputs; + wait_queue_head_t delayed_iputs_wait; /* this protects tree_mod_seq_list */ spinlock_t tree_mod_seq_lock; @@ -3237,6 +3238,7 @@ int btrfs_orphan_cleanup(struct btrfs_root *root); int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size); void btrfs_add_delayed_iput(struct inode *inode); void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info); +int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info); int btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index c5918ff8241b..3f81dfaefa32 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1692,9 +1692,7 @@ static int cleaner_kthread(void *arg) goto sleep; } - mutex_lock(&fs_info->cleaner_delayed_iput_mutex); btrfs_run_delayed_iputs(fs_info); - mutex_unlock(&fs_info->cleaner_delayed_iput_mutex); again = btrfs_clean_one_deleted_snapshot(root); mutex_unlock(&fs_info->cleaner_mutex); @@ -2651,7 +2649,6 @@ int open_ctree(struct super_block *sb, mutex_init(&fs_info->delete_unused_bgs_mutex); mutex_init(&fs_info->reloc_mutex); mutex_init(&fs_info->delalloc_root_mutex); - mutex_init(&fs_info->cleaner_delayed_iput_mutex); seqlock_init(&fs_info->profiles_lock); INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots); @@ -2673,6 +2670,7 @@ int open_ctree(struct super_block *sb, atomic_set(&fs_info->defrag_running, 0); atomic_set(&fs_info->qgroup_op_seq, 0); atomic_set(&fs_info->reada_works_cnt, 0); + atomic_set(&fs_info->nr_delayed_iputs, 0); atomic64_set(&fs_info->tree_mod_seq, 0); fs_info->sb = sb; fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE; @@ -2750,6 +2748,7 @@ int open_ctree(struct super_block *sb, init_waitqueue_head(&fs_info->transaction_wait); init_waitqueue_head(&fs_info->transaction_blocked_wait); init_waitqueue_head(&fs_info->async_submit_wait); + init_waitqueue_head(&fs_info->delayed_iputs_wait); INIT_LIST_HEAD(&fs_info->pinned_chunks); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 3a90dc1d6b31..36f43876be22 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4272,8 +4272,9 @@ int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes) * operations. Wait for it to finish so that * more space is released. */ - mutex_lock(&fs_info->cleaner_delayed_iput_mutex); - mutex_unlock(&fs_info->cleaner_delayed_iput_mutex); + ret = btrfs_wait_on_delayed_iputs(fs_info); + if (ret) + return ret; goto again; } else { btrfs_end_transaction(trans); @@ -4838,9 +4839,9 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, * pinned space, so make sure we run the iputs before we do our pinned * bytes check below. */ - mutex_lock(&fs_info->cleaner_delayed_iput_mutex); btrfs_run_delayed_iputs(fs_info); - mutex_unlock(&fs_info->cleaner_delayed_iput_mutex); + wait_event(fs_info->delayed_iputs_wait, + atomic_read(&fs_info->nr_delayed_iputs) == 0); trans = btrfs_join_transaction(fs_info->extent_root); if (IS_ERR(trans)) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 3c42d8887183..57bf514a90eb 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3260,6 +3260,7 @@ void btrfs_add_delayed_iput(struct inode *inode) if (atomic_add_unless(&inode->i_count, -1, 1)) return; + atomic_inc(&fs_info->nr_delayed_iputs); spin_lock(&fs_info->delayed_iput_lock); ASSERT(list_empty(&binode->delayed_iput)); list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); @@ -3279,11 +3280,31 @@ void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info) list_del_init(&inode->delayed_iput); spin_unlock(&fs_info->delayed_iput_lock); iput(&inode->vfs_inode); + if (atomic_dec_and_test(&fs_info->nr_delayed_iputs)) + wake_up(&fs_info->delayed_iputs_wait); spin_lock(&fs_info->delayed_iput_lock); } spin_unlock(&fs_info->delayed_iput_lock); } +/** + * btrfs_wait_on_delayed_iputs - wait on the delayed iputs to be done running + * @fs_info - the fs_info for this fs + * @return - EINTR if we were killed, 0 if nothing's pending + * + * This will wait on any delayed iputs that are currently running with KILLABLE + * set. Once they are all done running we will return, unless we are killed in + * which case we return EINTR. + */ +int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info) +{ + int ret = wait_event_killable(fs_info->delayed_iputs_wait, + atomic_read(&fs_info->nr_delayed_iputs) == 0); + if (ret) + return -EINTR; + return 0; +} + /* * This creates an orphan entry for the given inode in case something goes wrong * in the middle of an unlink.