From patchwork Mon Feb 21 07:56:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ritesh Harjani X-Patchwork-Id: 12753204 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60801C433F5 for ; Mon, 21 Feb 2022 07:56:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346597AbiBUH44 (ORCPT ); Mon, 21 Feb 2022 02:56:56 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:40904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346598AbiBUH4y (ORCPT ); Mon, 21 Feb 2022 02:56:54 -0500 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9D8CC49; Sun, 20 Feb 2022 23:56:31 -0800 (PST) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 21L5KFcZ030789; Mon, 21 Feb 2022 07:56:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=PmskHBvk9YyygPKmyeAxW3mTfC0jTkQ+gXzlUv9/kfk=; b=YUj8xii9DEoaSZvZc41GDq5eKYR8FCWFFp5+x7TiKFzCmn4ADcrG0fLZiil4IXJ6Cxkc 648q5SYgwZm+oNX1u7S0rpo6vF/QNUkx9jG5IGdfg4ncKLIP72NtzyxLfUN3mdgcY1Ft i6dRjxBij9guDLO7pPCPqcYtBxwVgnhVCu8mJ3BnCKed0rzCxIxxM59Vj0etjpjjCAgd Ute/d2Ak2F9BZ4VEdDHNDD38DSqFX0YgqAoWjrpDkr/+j6Ay0o42LqpzW52jmGu6x1Rl q4O/mR0OD0Ic8pxaiQVDBNdTIpuHKsEwVfnz9BipvMB6jg2AjqCduOov/ieif6dl3iE1 8A== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3ec0etxp6m-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 21 Feb 2022 07:56:27 +0000 Received: from m0098394.ppops.net (m0098394.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 21L7kKMK010789; Mon, 21 Feb 2022 07:56:27 GMT Received: from ppma01fra.de.ibm.com (46.49.7a9f.ip4.static.sl-reverse.com [159.122.73.70]) by mx0a-001b2d01.pphosted.com with ESMTP id 3ec0etxp61-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 21 Feb 2022 07:56:26 +0000 Received: from pps.filterd (ppma01fra.de.ibm.com [127.0.0.1]) by ppma01fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 21L7ipqt006766; Mon, 21 Feb 2022 07:56:24 GMT Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by ppma01fra.de.ibm.com with ESMTP id 3ear68qsr6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 21 Feb 2022 07:56:24 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 21L7uMgP58786162 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 21 Feb 2022 07:56:22 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2AC1BA404D; Mon, 21 Feb 2022 07:56:22 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id ACFF4A4040; Mon, 21 Feb 2022 07:56:21 +0000 (GMT) Received: from localhost (unknown [9.43.127.119]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 21 Feb 2022 07:56:21 +0000 (GMT) From: Ritesh Harjani To: linux-ext4@vger.kernel.org Cc: Harshad Shirwadkar , "Theodore Ts'o" , Jan Kara , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Ritesh Harjani Subject: [PATCHv2 1/1] ext4: Improve fast_commit performance and scalability Date: Mon, 21 Feb 2022 13:26:15 +0530 Message-Id: <930f35d4fd5f83e2673c868781d9ebf15e91bf4e.1645426817.git.riteshh@linux.ibm.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: HBZBy9MOmWD1EMedhCGYvYQq4Eq6A7ki X-Proofpoint-ORIG-GUID: T7Mhw7MQBgJ8wzteKsgaKyQ7JagH_EAk X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-02-21_02,2022-02-18_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 suspectscore=0 priorityscore=1501 phishscore=0 spamscore=0 mlxlogscore=583 clxscore=1015 malwarescore=0 bulkscore=0 lowpriorityscore=0 impostorscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2202210047 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Currently ext4_fc_commit_dentry_updates() is of quadratic time complexity, which is causing performance bottlenecks with high threads/file/dir count with fs_mark. This patch makes commit dentry updates (and hence ext4_fc_commit()) path to linear time complexity. Hence improves the performance of workloads which does fsync on multiple threads/open files one-by-one. Absolute numbers in avg file creates per sec (from fs_mark in 1K order) ======================================================================= no. Order without-patch(K) with-patch(K) Diff(%) 1 1 16.90 17.51 +3.60 2 2,2 32.08 31.80 -0.87 3 3,3 53.97 55.01 +1.92 4 4,4 78.94 76.90 -2.58 5 5,5 95.82 95.37 -0.46 6 6,6 87.92 103.38 +17.58 7 6,10 0.73 126.13 +17178.08 8 6,14 2.33 143.19 +6045.49 workload type ============== For e.g. 7th row order of 6,10 (2^6 == 64 && 2^10 == 1024) echo /run/riteshh/mnt/{1..64} |sed -E 's/[[:space:]]+/ -d /g' \ | xargs -I {} bash -c "sudo fs_mark -L 100 -D 1024 -n 1024 -s0 -S5 -d {}" Perf profile (w/o patches) ============================= 87.15% [kernel] [k] ext4_fc_commit --> Heavy contention/bottleneck 1.98% [kernel] [k] perf_event_interrupt 0.96% [kernel] [k] power_pmu_enable 0.91% [kernel] [k] update_sd_lb_stats.constprop.0 0.67% [kernel] [k] ktime_get Signed-off-by: Ritesh Harjani Reviewed-by: Harshad Shirwadkar --- fs/ext4/ext4.h | 2 ++ fs/ext4/fast_commit.c | 74 ++++++++++++++++++++++++++++++++----------- fs/ext4/fast_commit.h | 1 + 3 files changed, 59 insertions(+), 18 deletions(-) -- 2.31.1 diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0d4f284c0514..3f87cca49f0c 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1046,6 +1046,8 @@ struct ext4_inode_info { /* Fast commit related info */ + /* For tracking dentry create updates */ + struct list_head i_fc_dilist; struct list_head i_fc_list; /* * inodes that need fast commit * protected by sbi->s_fc_lock. diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index 3c5baca38767..5ac594e03402 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -199,6 +199,7 @@ void ext4_fc_init_inode(struct inode *inode) ext4_fc_reset_inode(inode); ext4_clear_inode_state(inode, EXT4_STATE_FC_COMMITTING); INIT_LIST_HEAD(&ei->i_fc_list); + INIT_LIST_HEAD(&ei->i_fc_dilist); init_waitqueue_head(&ei->i_fc_wait); atomic_set(&ei->i_fc_updates, 0); } @@ -279,6 +280,8 @@ void ext4_fc_stop_update(struct inode *inode) void ext4_fc_del(struct inode *inode) { struct ext4_inode_info *ei = EXT4_I(inode); + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + struct ext4_fc_dentry_update *fc_dentry; if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) || (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)) @@ -286,7 +289,7 @@ void ext4_fc_del(struct inode *inode) restart: spin_lock(&EXT4_SB(inode->i_sb)->s_fc_lock); - if (list_empty(&ei->i_fc_list)) { + if (list_empty(&ei->i_fc_list) && list_empty(&ei->i_fc_dilist)) { spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock); return; } @@ -295,8 +298,33 @@ void ext4_fc_del(struct inode *inode) ext4_fc_wait_committing_inode(inode); goto restart; } - list_del_init(&ei->i_fc_list); - spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock); + + if (!list_empty(&ei->i_fc_list)) + list_del_init(&ei->i_fc_list); + + /* + * Since this inode is getting removed, let's also remove all FC + * dentry create references, since it is not needed to log it anyways. + */ + if (list_empty(&ei->i_fc_dilist)) { + spin_unlock(&sbi->s_fc_lock); + return; + } + + fc_dentry = list_first_entry(&ei->i_fc_dilist, struct ext4_fc_dentry_update, fcd_dilist); + WARN_ON(fc_dentry->fcd_op != EXT4_FC_TAG_CREAT); + list_del_init(&fc_dentry->fcd_list); + list_del_init(&fc_dentry->fcd_dilist); + + WARN_ON(!list_empty(&ei->i_fc_dilist)); + spin_unlock(&sbi->s_fc_lock); + + if (fc_dentry->fcd_name.name && + fc_dentry->fcd_name.len > DNAME_INLINE_LEN) + kfree(fc_dentry->fcd_name.name); + kmem_cache_free(ext4_fc_dentry_cachep, fc_dentry); + + return; } /* @@ -427,7 +455,7 @@ static int __track_dentry_update(struct inode *inode, void *arg, bool update) node->fcd_name.name = node->fcd_iname; } node->fcd_name.len = dentry->d_name.len; - + INIT_LIST_HEAD(&node->fcd_dilist); spin_lock(&sbi->s_fc_lock); if (sbi->s_journal->j_flags & JBD2_FULL_COMMIT_ONGOING || sbi->s_journal->j_flags & JBD2_FAST_COMMIT_ONGOING) @@ -435,6 +463,20 @@ static int __track_dentry_update(struct inode *inode, void *arg, bool update) &sbi->s_fc_dentry_q[FC_Q_STAGING]); else list_add_tail(&node->fcd_list, &sbi->s_fc_dentry_q[FC_Q_MAIN]); + + /* + * This helps us keep a track of all fc_dentry updates which is part of + * this ext4 inode. So in case the inode is getting unlinked, before + * even we get a chance to fsync, we could remove all fc_dentry + * references while evicting the inode in ext4_fc_del(). + * Also with this, we don't need to loop over all the inodes in + * sbi->s_fc_q to get the corresponding inode in + * ext4_fc_commit_dentry_updates(). + */ + if (dentry_update->op == EXT4_FC_TAG_CREAT) { + WARN_ON(!list_empty(&ei->i_fc_dilist)); + list_add_tail(&node->fcd_dilist, &ei->i_fc_dilist); + } spin_unlock(&sbi->s_fc_lock); mutex_lock(&ei->i_fc_lock); @@ -954,7 +996,7 @@ __releases(&sbi->s_fc_lock) struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_fc_dentry_update *fc_dentry, *fc_dentry_n; struct inode *inode; - struct ext4_inode_info *ei, *ei_n; + struct ext4_inode_info *ei; int ret; if (list_empty(&sbi->s_fc_dentry_q[FC_Q_MAIN])) @@ -970,21 +1012,16 @@ __releases(&sbi->s_fc_lock) spin_lock(&sbi->s_fc_lock); continue; } - - inode = NULL; - list_for_each_entry_safe(ei, ei_n, &sbi->s_fc_q[FC_Q_MAIN], - i_fc_list) { - if (ei->vfs_inode.i_ino == fc_dentry->fcd_ino) { - inode = &ei->vfs_inode; - break; - } - } /* - * If we don't find inode in our list, then it was deleted, - * in which case, we don't need to record it's create tag. + * With fcd_dilist we need not loop in sbi->s_fc_q to get the + * corresponding inode pointer */ - if (!inode) - continue; + WARN_ON(list_empty(&fc_dentry->fcd_dilist)); + ei = list_first_entry(&fc_dentry->fcd_dilist, + struct ext4_inode_info, i_fc_dilist); + inode = &ei->vfs_inode; + WARN_ON(inode->i_ino != fc_dentry->fcd_ino); + spin_unlock(&sbi->s_fc_lock); /* @@ -1228,6 +1265,7 @@ static void ext4_fc_cleanup(journal_t *journal, int full, tid_t tid) struct ext4_fc_dentry_update, fcd_list); list_del_init(&fc_dentry->fcd_list); + list_del_init(&fc_dentry->fcd_dilist); spin_unlock(&sbi->s_fc_lock); if (fc_dentry->fcd_name.name && diff --git a/fs/ext4/fast_commit.h b/fs/ext4/fast_commit.h index 083ad1cb705a..02afa52e8e41 100644 --- a/fs/ext4/fast_commit.h +++ b/fs/ext4/fast_commit.h @@ -109,6 +109,7 @@ struct ext4_fc_dentry_update { struct qstr fcd_name; /* Dirent name */ unsigned char fcd_iname[DNAME_INLINE_LEN]; /* Dirent name string */ struct list_head fcd_list; + struct list_head fcd_dilist; }; struct ext4_fc_stats {