From patchwork Wed Mar 26 11:22:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 14029985 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 742101C8635; Wed, 26 Mar 2025 11:22:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742988149; cv=none; b=uuBAQW2mLOIlEogvUibPU7NtBD63aI3FPH+rAbiLWcqb+9gIrhVVfQUpW6D9FkCd1qInf6UkbfdbLSX3X3eNbcyuYmsln7UGn7eHTzzvfK+4ajQ770lfE3Oyo+tor01f5y+7z+xbyX+Pm+j1M37Kxzdo3KAv+Dl9dczK823gRig= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742988149; c=relaxed/simple; bh=7oEB3iyiQ+3DRRjgaNKNQIcZL+vSTPPPNL/kxJwh2i0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Aq3MfNEtYo/8zQNadLXtl59w8SfaD4vrRxUBxSGR0hx/3/B6oAXbq9s807uwbsGyE9iWH7AM1UbDOwAzxAGoSvft106Geh/uHDw6wVWVf4Z5Ut3JhZJkL4rtAxfH1/Z0F38FVcl3H4j/fFfeD8rdJOc1iYUAcXCSjMcamGdAEaw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=E2HwO4rh; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="E2HwO4rh" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=84t0ULXhvJVB5iCtiqB96HKwPHTuYkS+RDsGjxv7yJ8=; b=E2HwO4rhIJg+H9626l3KLfQDl9 y/6dLebcHCJYdXQiHUwNc31o2HC9poJGeOKH0wQjmlXC7bGya+pRLUj2qj/pOEIQ0b6/d1Cj2KISI k17P04jGFxiKwfplwfIAVfGSB434gBGIECpfP1YM5eOdVFX0OWfnmrcnQ1oAChucfn2SmaEHGN4K0 igiMYj9/o9OC/tcwxfz5wlQXq9S3TP89E8xJi/j6qwoUL6bEBToFzbQMOh6RaPFHx1N7TLfHOSMue SE3TDWXkpN9x5+Z9kGAVc96M3LnVxMk7lJWFavWaECSPl24lu6pHyEQw5+j+J8r9ftvs19LzvFnIb ryZiGwRw==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.98.1 #2 (Red Hat Linux)) id 1txOq0-00000008LM5-3FP6; Wed, 26 Mar 2025 11:22:24 +0000 From: Luis Chamberlain To: jack@suse.cz, hch@infradead.org, James.Bottomley@HansenPartnership.com, david@fromorbit.com, rafael@kernel.org, djwong@kernel.org, pavel@kernel.org, song@kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, gost.dev@samsung.com, Luis Chamberlain Subject: [RFC 4/6] ext4: replace kthread freezing with auto fs freezing Date: Wed, 26 Mar 2025 04:22:18 -0700 Message-ID: <20250326112220.1988619-5-mcgrof@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250326112220.1988619-1-mcgrof@kernel.org> References: <20250326112220.1988619-1-mcgrof@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Sender: Luis Chamberlain The kernel power management now supports allowing the VFS to handle filesystem freezing freezes and thawing. Take advantage of that and remove the kthread freezing. This is needed so that we properly really stop IO in flight without races after userspace has been frozen. Without this we rely on kthread freezing and its semantics are loose and error prone. The filesystem therefore is in charge of properly dealing with quiescing of the filesystem through its callbacks if it thinks it knows better than how the VFS handles it. The following Coccinelle rule was used as to remove the now superfluous freezer calls: make coccicheck MODE=patch SPFLAGS="--in-place --no-show-diff" COCCI=./fs-freeze-cleanup.cocci M=fs/ext4 virtual patch @ remove_set_freezable @ expression time; statement S, S2; expression task, current; @@ ( - set_freezable(); | - if (try_to_freeze()) - continue; | - try_to_freeze(); | - freezable_schedule(); + schedule(); | - freezable_schedule_timeout(time); + schedule_timeout(time); | - if (freezing(task)) { S } | - if (freezing(task)) { S } - else { S2 } | - freezing(current) ) @ remove_wq_freezable @ expression WQ_E, WQ_ARG1, WQ_ARG2, WQ_ARG3, WQ_ARG4; identifier fs_wq_fn; @@ ( WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_FREEZABLE, + WQ_ARG2, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_FREEZABLE | WQ_ARG3, + WQ_ARG2 | WQ_ARG3, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_ARG3 | WQ_FREEZABLE, + WQ_ARG2 | WQ_ARG3, ...); | WQ_E = alloc_workqueue(WQ_ARG1, - WQ_ARG2 | WQ_ARG3 | WQ_FREEZABLE | WQ_ARG4, + WQ_ARG2 | WQ_ARG3 | WQ_ARG4, ...); | WQ_E = - WQ_ARG1 | WQ_FREEZABLE + WQ_ARG1 | WQ_E = - WQ_ARG1 | WQ_FREEZABLE | WQ_ARG3 + WQ_ARG1 | WQ_ARG3 | fs_wq_fn( - WQ_FREEZABLE | WQ_ARG2 | WQ_ARG3 + WQ_ARG2 | WQ_ARG3 ) | fs_wq_fn( - WQ_FREEZABLE | WQ_ARG2 + WQ_ARG2 ) | fs_wq_fn( - WQ_FREEZABLE + 0 ) ) @ add_auto_flag @ expression E1; identifier fs_type; @@ struct file_system_type fs_type = { .fs_flags = E1 + | FS_AUTOFREEZE , }; Generated-by: Coccinelle SmPL Signed-off-by: Luis Chamberlain --- fs/ext4/mballoc.c | 2 +- fs/ext4/super.c | 9 +++------ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 0d523e9fb3d5..ae235ec5ff3a 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -6782,7 +6782,7 @@ static ext4_grpblk_t ext4_last_grp_cluster(struct super_block *sb, static bool ext4_trim_interrupted(void) { - return fatal_signal_pending(current) || freezing(current); + return fatal_signal_pending(current); } static int ext4_try_to_trim_range(struct super_block *sb, diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 8cafcd3e9f5f..4241043262c8 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -136,7 +136,7 @@ static struct file_system_type ext2_fs_type = { .init_fs_context = ext4_init_fs_context, .parameters = ext4_param_specs, .kill_sb = ext4_kill_sb, - .fs_flags = FS_REQUIRES_DEV, + .fs_flags = FS_REQUIRES_DEV | FS_AUTOFREEZE, }; MODULE_ALIAS_FS("ext2"); MODULE_ALIAS("ext2"); @@ -152,7 +152,7 @@ static struct file_system_type ext3_fs_type = { .init_fs_context = ext4_init_fs_context, .parameters = ext4_param_specs, .kill_sb = ext4_kill_sb, - .fs_flags = FS_REQUIRES_DEV, + .fs_flags = FS_REQUIRES_DEV | FS_AUTOFREEZE, }; MODULE_ALIAS_FS("ext3"); MODULE_ALIAS("ext3"); @@ -3776,7 +3776,6 @@ static int ext4_lazyinit_thread(void *arg) unsigned long next_wakeup, cur; BUG_ON(NULL == eli); - set_freezable(); cont_thread: while (true) { @@ -3835,8 +3834,6 @@ static int ext4_lazyinit_thread(void *arg) } mutex_unlock(&eli->li_list_mtx); - try_to_freeze(); - cur = jiffies; if (!next_wakeup_initialized || time_after_eq(cur, next_wakeup)) { cond_resched(); @@ -7404,7 +7401,7 @@ static struct file_system_type ext4_fs_type = { .init_fs_context = ext4_init_fs_context, .parameters = ext4_param_specs, .kill_sb = ext4_kill_sb, - .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME, + .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME | FS_AUTOFREEZE, }; MODULE_ALIAS_FS("ext4");