From nobody Sat Jun 13 09:21:03 2026 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AC2AD3203B6; Fri, 8 May 2026 09:35:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.2 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232922; cv=none; b=OHxNOm3vMe39ZNUnCWw7JpFHuSiYdo3c9Fn/MoY7njeivhjuKLIEF8YW+O1FOW8HE0yI47rvF64s+4sFiGTtVUM7QV2V9Pg/LNNMI8hVx6lE8tiL8SkOZ6Sl0rOENdrgUeMIjp4NqRmamF36jckmot+xUe4LTBCWocsQc0uu2xE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232922; c=relaxed/simple; bh=SiyEP1WZSP5zJJz4PdRF92qWLnENtw7v20M5ZPSdrjA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DCQ9ACIe7jHh0efW4Tlrx+qE6qN6BzTtjbcPj4HALNr6taGtQRwR6H1Uq4jMaoVfqplQLH7pXHzrMRdTxJWLbTxoo7tAapl3LAGHkDdK6a0fmNMEGe11Jb7lm3Qi6o1eXbh6ph0dpcOD+tBMz3gwJ3owqQAweQc9Z0DRoZbKTyI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=F8rz2NEs; arc=none smtp.client-ip=117.135.210.2 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="F8rz2NEs" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=45 c6wya7N0PUbeskGcHwwrqhFeuHXefamz6GyNQYArQ=; b=F8rz2NEsJ4GrLXqxx3 06QVrnvyywfCS4xk0U7XYAh/80JxTseBEv6xbtaxh50Sd41KH2PAbv+snFkviFLg 9dhjQ7PSJOW7KBhk82YOPJl+1EtHNqEwOHiJ48OLdWHj7pPUNT4sFCGIFP+FVujH RD5lBzTmVCZgbB4ziJXBBix6o= Received: from liubaolin-VMware-Virtual-Platform.localdomain (unknown []) by gzsmtp2 (Coremail) with SMTP id PSgvCgDXeCEprv1pUW9wDg--.60442S3; Fri, 08 May 2026 17:34:52 +0800 (CST) From: Baolin Liu To: tytso@mit.edu, adilger.kernel@dilger.ca, libaokun@linux.alibaba.com Cc: ojaswin@linux.ibm.com, ritesh.list@gmail.com, yi.zhang@huawei.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, wangguanyu@vivo.com, adilger@dilger.ca, liubaolin12138@163.com, Baolin Liu Subject: [PATCH v4 v4 1/3] ext4: add blocks_allocated to mb_stats output Date: Fri, 8 May 2026 17:34:26 +0800 Message-ID: <20260508093428.5814-2-liubaolin12138@163.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260508093428.5814-1-liubaolin12138@163.com> References: <20260508093428.5814-1-liubaolin12138@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: PSgvCgDXeCEprv1pUW9wDg--.60442S3 X-Coremail-Antispam: 1Uf129KBjvdXoWrtr1Utr4xurW8GFykAryxKrg_yoWkGrX_Ka 40yr18ur45Jr4xuF18AFsa9rZ0k3W0vFn8W3sxJrZ3Wa4DW3y8ta98Ar4rXr1xGr42krW5 A3Z3Wry8JryvvjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7sR_QzV7UUUUU== X-CM-SenderInfo: xolxutxrol0iasrtmqqrwthudrp/xtbCwR2UX2n9rj07fwAA3U Content-Type: text/plain; charset="utf-8" From: Baolin Liu Add blocks_allocated to /proc/fs/ext4//mb_stats so that the reported statistics match the mballoc summary printed at unmount time. Reviewed-by: Ojaswin Mujoo Reviewed-by: Andreas Dilger Reviewed-by: Ritesh Harjani (IBM) Reviewed-by: Zhang Yi Signed-off-by: Baolin Liu --- fs/ext4/mballoc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 20e9fdaf4301..1e13ef62cb9d 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3211,6 +3211,8 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void= *offset) "\tTo enable, please write \"1\" to sysfs file mb_stats.\n"); return 0; } + seq_printf(seq, "\tblocks_allocated: %u\n", + atomic_read(&sbi->s_bal_allocated)); seq_printf(seq, "\treqs: %u\n", atomic_read(&sbi->s_bal_reqs)); seq_printf(seq, "\tsuccess: %u\n", atomic_read(&sbi->s_bal_success)); =20 --=20 2.51.0 From nobody Sat Jun 13 09:21:03 2026 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8F753C0633; Fri, 8 May 2026 09:35:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.4 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232936; cv=none; b=e+iGiekJ68Rd5hHSmeqkMd8RmbROiSbsyJ3ODQqhVHzciR186Odlh40DPfhM5jBO3yq/9o22iOO0H302zCkh/vcZ/wu4w9fxzt4Lk4wWOdLnmT8reK07uKJE25VS4cbClO/prejKMQIAhJiwrMO1xEmOT7SlvB5435zQDI4vwn8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232936; c=relaxed/simple; bh=iLEMVuIUAYNxQld7HNPZ4x6eyg9UYHHvPCzN+/WuXjo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Gjbp7IwQ+ZERsr9SZqyBw9vA5RQAJigeiXTIAsIMsVHc2G5EJ2l956b7Wd/8XV8EI3rriyA42o0nrCq3e5gVNZvZI3inAZAnGE3lwWJ6JDvw8wsbbX0iWEogN/megIDCfBBZ0WYcbRMxODq0w5aYAw7Uv4x96VBAdiof30qSjss= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=Ef0SfN4O; arc=none smtp.client-ip=220.197.31.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="Ef0SfN4O" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=Ho x6VtJtqn/K6Bdh5hfLYu35wGS6LKEAxmhmuB+uoe4=; b=Ef0SfN4OpTU0tKeQ56 8+1ipUPsd6CmNBgVdtL4bv5FZlljgs2yrJYDGk5OV0ImkZzk+BCxS2XUKZExjp1U gl0VcFR5tpWj1cYdoE5ZCXGFPr8va9Gqqig+0fSZ+SDZFWq1cry6Xdy8Z5CJ3X/0 FlFizDrIpUc1YRDjXekWpuT8g= Received: from liubaolin-VMware-Virtual-Platform.localdomain (unknown []) by gzsmtp2 (Coremail) with SMTP id PSgvCgDXeCEprv1pUW9wDg--.60442S4; Fri, 08 May 2026 17:34:56 +0800 (CST) From: Baolin Liu To: tytso@mit.edu, adilger.kernel@dilger.ca, libaokun@linux.alibaba.com Cc: ojaswin@linux.ibm.com, ritesh.list@gmail.com, yi.zhang@huawei.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, wangguanyu@vivo.com, adilger@dilger.ca, liubaolin12138@163.com, Baolin Liu Subject: [PATCH v4 v4 2/3] ext4: use atomic operations for s_mb_stats accesses Date: Fri, 8 May 2026 17:34:27 +0800 Message-ID: <20260508093428.5814-3-liubaolin12138@163.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260508093428.5814-1-liubaolin12138@163.com> References: <20260508093428.5814-1-liubaolin12138@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: PSgvCgDXeCEprv1pUW9wDg--.60442S4 X-Coremail-Antispam: 1Uf129KBjvJXoW3ArWkAw4rtry5Ww48tr4UCFg_yoWxAFWxpr srZFyUAr48Zw18uF4DWa98W3Z5K3y0k347Jr4S934fuFyavFyFyasaqFyUAFyDArWDAFn5 Z3yqyrWDGrWIka7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zNiifUUUUUU= X-CM-SenderInfo: xolxutxrol0iasrtmqqrwthudrp/xtbC6QCVYGn9rkB+7gAA32 Content-Type: text/plain; charset="utf-8" From: Baolin Liu s_mb_stats can be read from mballoc paths while being updated through sysfs, which can race. Convert it to atomic_t and use atomic_read()/atomic_set() for all accesses. Signed-off-by: Baolin Liu --- fs/ext4/ext4.h | 2 +- fs/ext4/mballoc.c | 24 ++++++++++++------------ fs/ext4/sysfs.c | 9 ++++++++- 3 files changed, 21 insertions(+), 14 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 293f698b7042..04bccfcb018e 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1624,7 +1624,7 @@ struct ext4_sb_info { unsigned int s_mb_stream_request; unsigned int s_mb_max_to_scan; unsigned int s_mb_min_to_scan; - unsigned int s_mb_stats; + atomic_t s_mb_stats; unsigned int s_mb_order2_reqs; unsigned int s_mb_group_prealloc; unsigned int s_max_dir_size_kb; diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 1e13ef62cb9d..95103fbc1583 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -924,7 +924,7 @@ static int ext4_mb_scan_groups_xa_range(struct ext4_all= ocation_context *ac, xa_for_each_range(xa, group, grp, start, end - 1) { int err; =20 - if (sbi->s_mb_stats) + if (atomic_read(&sbi->s_mb_stats)) atomic64_inc(&sbi->s_bal_cX_groups_considered[cr]); =20 err =3D ext4_mb_scan_group(ac, grp->bb_group); @@ -980,7 +980,7 @@ static int ext4_mb_scan_groups_p2_aligned(struct ext4_a= llocation_context *ac, goto wrap_around; } =20 - if (sbi->s_mb_stats) + if (atomic_read(&sbi->s_mb_stats)) atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); =20 /* Increment cr and search again if no group is found */ @@ -1031,7 +1031,7 @@ static int ext4_mb_scan_groups_goal_fast(struct ext4_= allocation_context *ac, goto wrap_around; } =20 - if (sbi->s_mb_stats) + if (atomic_read(&sbi->s_mb_stats)) atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); /* * CR_BEST_AVAIL_LEN works based on the concept that we have @@ -1135,7 +1135,7 @@ static int ext4_mb_scan_groups_best_avail(struct ext4= _allocation_context *ac, =20 /* Reset goal length to original goal length before falling into CR_GOAL_= LEN_SLOW */ ac->ac_g_ex.fe_len =3D ac->ac_orig_goal_len; - if (sbi->s_mb_stats) + if (atomic_read(&sbi->s_mb_stats)) atomic64_inc(&sbi->s_bal_cX_failed[ac->ac_criteria]); ac->ac_criteria =3D CR_GOAL_LEN_SLOW; =20 @@ -1184,7 +1184,7 @@ static int ext4_mb_scan_groups_linear(struct ext4_all= ocation_context *ac, ac->ac_criteria++; =20 /* Processed all groups and haven't found blocks */ - if (sbi->s_mb_stats && i =3D=3D ngroups) + if (atomic_read(&sbi->s_mb_stats) && i =3D=3D ngroups) atomic64_inc(&sbi->s_bal_cX_failed[cr]); =20 return 0; @@ -2535,7 +2535,7 @@ void ext4_mb_simple_scan_group(struct ext4_allocation= _context *ac, =20 BUG_ON(ac->ac_f_ex.fe_len !=3D ac->ac_g_ex.fe_len); =20 - if (EXT4_SB(sb)->s_mb_stats) + if (atomic_read(&EXT4_SB(sb)->s_mb_stats)) atomic_inc(&EXT4_SB(sb)->s_bal_2orders); =20 break; @@ -2780,7 +2780,7 @@ static int ext4_mb_good_group_nolock(struct ext4_allo= cation_context *ac, =20 if (!grp) return -EFSCORRUPTED; - if (sbi->s_mb_stats) + if (atomic_read(&sbi->s_mb_stats)) atomic64_inc(&sbi->s_bal_cX_groups_considered[ac->ac_criteria]); if (should_lock) { ext4_lock_group(sb, group); @@ -3091,7 +3091,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_cont= ext *ac) } } =20 - if (sbi->s_mb_stats && ac->ac_status =3D=3D AC_STATUS_FOUND) { + if (atomic_read(&sbi->s_mb_stats) && ac->ac_status =3D=3D AC_STATUS_FOUND= ) { atomic64_inc(&sbi->s_bal_cX_hits[ac->ac_criteria]); if (ac->ac_flags & EXT4_MB_STREAM_ALLOC && ac->ac_b_ex.fe_group =3D=3D ac->ac_g_ex.fe_group) @@ -3204,7 +3204,7 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void= *offset) struct ext4_sb_info *sbi =3D EXT4_SB(sb); =20 seq_puts(seq, "mballoc:\n"); - if (!sbi->s_mb_stats) { + if (!atomic_read(&sbi->s_mb_stats)) { seq_puts(seq, "\tmb stats collection turned off.\n"); seq_puts( seq, @@ -3783,7 +3783,7 @@ int ext4_mb_init(struct super_block *sb) =20 sbi->s_mb_max_to_scan =3D MB_DEFAULT_MAX_TO_SCAN; sbi->s_mb_min_to_scan =3D MB_DEFAULT_MIN_TO_SCAN; - sbi->s_mb_stats =3D MB_DEFAULT_STATS; + atomic_set(&sbi->s_mb_stats, MB_DEFAULT_STATS); sbi->s_mb_stream_request =3D MB_DEFAULT_STREAM_THRESHOLD; sbi->s_mb_order2_reqs =3D MB_DEFAULT_ORDER2_REQS; sbi->s_mb_best_avail_max_trim_order =3D MB_DEFAULT_BEST_AVAIL_TRIM_ORDER; @@ -3929,7 +3929,7 @@ void ext4_mb_release(struct super_block *sb) kfree(sbi->s_mb_offsets); kfree(sbi->s_mb_maxs); iput(sbi->s_buddy_cache); - if (sbi->s_mb_stats) { + if (atomic_read(&sbi->s_mb_stats)) { ext4_msg(sb, KERN_INFO, "mballoc: %u blocks %u reqs (%u success)", atomic_read(&sbi->s_bal_allocated), @@ -4694,7 +4694,7 @@ static void ext4_mb_collect_stats(struct ext4_allocat= ion_context *ac) { struct ext4_sb_info *sbi =3D EXT4_SB(ac->ac_sb); =20 - if (sbi->s_mb_stats && ac->ac_g_ex.fe_len >=3D 1) { + if (atomic_read(&sbi->s_mb_stats) && ac->ac_g_ex.fe_len >=3D 1) { atomic_inc(&sbi->s_bal_reqs); atomic_add(ac->ac_b_ex.fe_len, &sbi->s_bal_allocated); if (ac->ac_b_ex.fe_len >=3D ac->ac_o_ex.fe_len) diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index b87d7bdab06a..0f65ab372dee 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -250,7 +250,7 @@ EXT4_ATTR_OFFSET(mb_best_avail_max_trim_order, 0644, mb= _order, ext4_sb_info, s_mb_best_avail_max_trim_order); EXT4_ATTR_OFFSET(err_report_sec, 0644, err_report_sec, ext4_sb_info, s_err= _report_sec); EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); -EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); +EXT4_ATTR_OFFSET(mb_stats, 0644, pointer_atomic, ext4_sb_info, s_mb_stats); EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan); EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); @@ -493,6 +493,7 @@ static ssize_t ext4_generic_attr_store(struct ext4_attr= *a, const char *buf, size_t len) { int ret; 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d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=h8 +2ejIaLAunVzHWwrUrleLK9mjHS6IbId81JKiL/14=; b=U16ZO1IXdyk3g2c6q3 K2JyTCnMjlJC7CTwVQ4/UZ2hj4TyWVHPUNZxyQli5sUZ6geZwXs12H8+MaI+WyBS fj/Ug8EkuzuKet9YpfrLTnm9QJPhAIbXXtCklyofMdpgMbFNHx963pb+po1xhqVR LiBL1T2cjXZFSh48I9caOFyCk= Received: from liubaolin-VMware-Virtual-Platform.localdomain (unknown []) by gzsmtp2 (Coremail) with SMTP id PSgvCgDXeCEprv1pUW9wDg--.60442S5; Fri, 08 May 2026 17:35:02 +0800 (CST) From: Baolin Liu To: tytso@mit.edu, adilger.kernel@dilger.ca, libaokun@linux.alibaba.com Cc: ojaswin@linux.ibm.com, ritesh.list@gmail.com, yi.zhang@huawei.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, wangguanyu@vivo.com, adilger@dilger.ca, liubaolin12138@163.com, Baolin Liu Subject: [PATCH v4 v4 3/3] ext4: allow controlling mballoc stats through proc mb_stats Date: Fri, 8 May 2026 17:34:28 +0800 Message-ID: <20260508093428.5814-4-liubaolin12138@163.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260508093428.5814-1-liubaolin12138@163.com> References: <20260508093428.5814-1-liubaolin12138@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: PSgvCgDXeCEprv1pUW9wDg--.60442S5 X-Coremail-Antispam: 1Uf129KBjvJXoW3Gw1kXFy3Ar4rXw13uw47XFb_yoW3tF4kpF sxAa4xGr1xWa4UCws7Gr4xXw13A3W8C347Kr1I9340gr9IvryFyF1ftrW0yFy5GrWUAa95 XF4j9ryUGr42k37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zRFtCcUUUUU= X-CM-SenderInfo: xolxutxrol0iasrtmqqrwthudrp/xtbCwgaWYWn9rkZEZwAA3s Content-Type: text/plain; charset="utf-8" From: Baolin Liu Make /proc/fs/ext4//mb_stats writable. Writing 0 disables mballoc statistics collection, writing 1 enables it, and writing -1 clears the current statistics before enabling collection. Update the ext4 documentation for proc mb_stats, document that the sysfs mb_stats entry is deprecated, and point proc.rst to Documentation/admin-guide/ext4.rst for ext4-specific /proc entries. Reviewed-by: Ojaswin Mujoo Reviewed-by: Andreas Dilger Reviewed-by: Ritesh Harjani (IBM) Reviewed-by: Zhang Yi Reviewed-by: Baokun Li Reviewed-by: Ted Tso Signed-off-by: Baolin Liu --- Documentation/ABI/testing/sysfs-fs-ext4 | 3 +- Documentation/admin-guide/ext4.rst | 9 ++++- Documentation/filesystems/proc.rst | 13 +------ fs/ext4/ext4.h | 1 + fs/ext4/mballoc.c | 31 ++++++++++++++++- fs/ext4/sysfs.c | 46 +++++++++++++++++++++++-- 6 files changed, 86 insertions(+), 17 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-fs-ext4 b/Documentation/ABI/te= sting/sysfs-fs-ext4 index 2edd0a6672d3..7bf06c533343 100644 --- a/Documentation/ABI/testing/sysfs-fs-ext4 +++ b/Documentation/ABI/testing/sysfs-fs-ext4 @@ -5,7 +5,8 @@ Description: Controls whether the multiblock allocator should collect statistics, which are shown during the unmount. 1 means to collect statistics, 0 means not to collect - statistics + statistics. This sysfs entry is deprecated, and users + should prefer /proc/fs/ext4//mb_stats. =20 What: /sys/fs/ext4//mb_group_prealloc Date: March 2008 diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide= /ext4.rst index ac0c709ea9e7..ca76e981b2aa 100644 --- a/Documentation/admin-guide/ext4.rst +++ b/Documentation/admin-guide/ext4.rst @@ -436,6 +436,12 @@ Files in /proc/fs/ext4/ mb_groups details of multiblock allocator buddy cache of free blocks =20 + mb_stats + reports runtime statistics from the multiblock allocator + (mballoc). Writing 0 disables statistics collection, writing + 1 enables statistics collection, and writing -1 clears the + current statistics and enables statistics collection. + /sys entries =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =20 @@ -493,7 +499,8 @@ Files in /sys/fs/ext4/: mb_stats Controls whether the multiblock allocator should collect statistic= s, which are shown during the unmount. 1 means to collect statistics,= 0 - means not to collect statistics. + means not to collect statistics. This sysfs entry is deprecated, a= nd + users should prefer /proc/fs/ext4//mb_stats. =20 mb_stream_req Files which have fewer blocks than this tunable parameter will have diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems= /proc.rst index b0c0d1b45b99..dd487004b862 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -1623,18 +1623,7 @@ softirq. 1.8 Ext4 file system parameters ------------------------------- =20 -Information about mounted ext4 file systems can be found in -/proc/fs/ext4. Each mounted filesystem will have a directory in -/proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or -/proc/fs/ext4/sda9 or /proc/fs/ext4/dm-0). The files in each per-device -directory are shown in Table 1-12, below. - -.. table:: Table 1-12: Files in /proc/fs/ext4/ - - =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D - File Content - mb_groups details of multiblock allocator buddy cache of free blocks - =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +See Documentation/admin-guide/ext4.rst for ext4-specific /proc entries. =20 1.9 /proc/consoles ------------------- diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 04bccfcb018e..536589dda8d1 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2994,6 +2994,7 @@ int ext4_fc_record_regions(struct super_block *sb, in= t ino, extern const struct seq_operations ext4_mb_seq_groups_ops; extern const struct seq_operations ext4_mb_seq_structs_summary_ops; extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset); +extern void ext4_mb_stats_clear(struct ext4_sb_info *sbi); extern int ext4_mb_init(struct super_block *); extern void ext4_mb_release(struct super_block *); extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *, diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 95103fbc1583..69ee737f8655 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3208,7 +3208,7 @@ int ext4_seq_mb_stats_show(struct seq_file *seq, void= *offset) seq_puts(seq, "\tmb stats collection turned off.\n"); seq_puts( seq, - "\tTo enable, please write \"1\" to sysfs file mb_stats.\n"); + "\tTo enable, please write \"1\" to proc file mb_stats.\n"); return 0; } seq_printf(seq, "\tblocks_allocated: %u\n", @@ -4723,6 +4723,35 @@ static void ext4_mb_collect_stats(struct ext4_alloca= tion_context *ac) trace_ext4_mballoc_prealloc(ac); } =20 +void ext4_mb_stats_clear(struct ext4_sb_info *sbi) +{ + int i; + + atomic_set(&sbi->s_bal_reqs, 0); + atomic_set(&sbi->s_bal_success, 0); + atomic_set(&sbi->s_bal_allocated, 0); + atomic_set(&sbi->s_bal_groups_scanned, 0); + + for (i =3D 0; i < EXT4_MB_NUM_CRS; i++) { + atomic64_set(&sbi->s_bal_cX_hits[i], 0); + atomic64_set(&sbi->s_bal_cX_groups_considered[i], 0); + atomic_set(&sbi->s_bal_cX_ex_scanned[i], 0); + atomic64_set(&sbi->s_bal_cX_failed[i], 0); + } + + atomic_set(&sbi->s_bal_ex_scanned, 0); + atomic_set(&sbi->s_bal_goals, 0); + atomic_set(&sbi->s_bal_stream_goals, 0); + atomic_set(&sbi->s_bal_len_goals, 0); + atomic_set(&sbi->s_bal_2orders, 0); + atomic_set(&sbi->s_bal_breaks, 0); + atomic_set(&sbi->s_mb_lost_chunks, 0); + atomic_set(&sbi->s_mb_buddies_generated, 0); + atomic64_set(&sbi->s_mb_generation_time, 0); + atomic_set(&sbi->s_mb_preallocated, 0); + atomic_set(&sbi->s_mb_discarded, 0); +} + /* * Called on failure; free up any blocks from the inode PA for this * context. We don't need this for MB_GROUP_PA because we only change diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index 0f65ab372dee..86e2ae022659 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -52,6 +52,48 @@ typedef enum { static const char proc_dirname[] =3D "fs/ext4"; static struct proc_dir_entry *ext4_proc_root; =20 +static int ext4_mb_stats_open(struct inode *inode, struct file *file) +{ + return single_open(file, ext4_seq_mb_stats_show, pde_data(inode)); +} + +static ssize_t ext4_mb_stats_write(struct file *file, const char __user *b= uf, + size_t count, loff_t *ppos) +{ + struct super_block *sb =3D pde_data(file_inode(file)); + struct ext4_sb_info *sbi =3D EXT4_SB(sb); + int val; + int ret; + + ret =3D kstrtoint_from_user(buf, count, 0, &val); + if (ret) + return ret; + + switch (val) { + case -1: + ext4_mb_stats_clear(sbi); + fallthrough; + case 1: + atomic_set(&sbi->s_mb_stats, 1); + break; + case 0: + atomic_set(&sbi->s_mb_stats, 0); + break; + default: + return -EINVAL; + } + + return count; +} + +static const struct proc_ops ext4_mb_stats_proc_ops =3D { + .proc_open =3D ext4_mb_stats_open, + .proc_read =3D seq_read, + .proc_lseek =3D seq_lseek, + .proc_release =3D single_release, + .proc_write =3D ext4_mb_stats_write, +}; + struct ext4_attr { struct attribute attr; short attr_id; @@ -637,8 +679,8 @@ int ext4_register_sysfs(struct super_block *sb) ext4_fc_info_show, sb); proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc, &ext4_mb_seq_groups_ops, sb); - proc_create_single_data("mb_stats", 0444, sbi->s_proc, - ext4_seq_mb_stats_show, sb); + proc_create_data("mb_stats", 0644, sbi->s_proc, + &ext4_mb_stats_proc_ops, sb); proc_create_seq_data("mb_structs_summary", 0444, sbi->s_proc, &ext4_mb_seq_structs_summary_ops, sb); } --=20 2.51.0