From patchwork Sat Jan 27 07:47:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13533995 X-Patchwork-Delegate: snitzer@redhat.com Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) (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 F3CD72111B for ; Sat, 27 Jan 2024 07:52:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706341953; cv=none; b=go9h7MObkSOUoqnCGHHJ7I5Hjz+8FUoaOQvpYvLbg/J5x4oML91v6QDgk7StRrG3850bq3O1UG/QutlEMug9A+Ak45HTHyvfyq+Rz9EszE2zk3fAvryVhxzsmqWBqZkJGJjjUfoQsp0uC8wUSIDWZhW90MmDsESN6kTQTjZkEqs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706341953; c=relaxed/simple; bh=6BrWeORSG3spzobIm2H1STSTTDZ6J8PBa6b1+irB9U4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=JR8nkNdaDZuyskiHG+zQBjS85ZpMx1/l5b7vkB6SKm66KW8yKEucSWXyMPiWBOMTQP7wRaURjgVkZH5/DqTu+2DI7kdtqquwba04KDU/8Q1iR4K9m9FUGB5fzqWlas8HlOv2aKlVCy6RRh/vIrI4c43OhUC9/ud97g94AI0MFlU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4TMRc90gLvz4f3jsQ for ; Sat, 27 Jan 2024 15:52:25 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id 1B6A31A0272 for ; Sat, 27 Jan 2024 15:52:29 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgDHlxAetrRlWjeACA--.31980S10; Sat, 27 Jan 2024 15:52:28 +0800 (CST) From: Yu Kuai To: mpatocka@redhat.com, heinzm@redhat.com, xni@redhat.com, agk@redhat.com, snitzer@kernel.org, dm-devel@lists.linux.dev, song@kernel.org, yukuai3@huawei.com, jbrassow@f14.redhat.com, neilb@suse.de, shli@fb.com, akpm@osdl.org Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH v3 06/12] dm-raid: really frozen sync_thread during suspend Date: Sat, 27 Jan 2024 15:47:48 +0800 Message-Id: <20240127074754.2380890-7-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240127074754.2380890-1-yukuai1@huaweicloud.com> References: <20240127074754.2380890-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgDHlxAetrRlWjeACA--.31980S10 X-Coremail-Antispam: 1UD129KBjvJXoWxur1xXF4fWry8tryDtFW3trb_yoWrKw15pa yrtws0vw48JrW7Za9Fy3WkXFWYvwnIgrWUtr93WayrJ3WSkws3ury8Kw47ZFWDtFyxJa4Y yr4Dtw45uFWjgFJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPI14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr 0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQ SdkUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai 1) The flag MD_RECOVERY_FROZEN doesn't mean that sync thread is frozen, it only prevent new sync_thread to start, and it can't stop the running sync thread; 2) The flag MD_RECOVERY_FROZEN doesn't mean that writes are stopped, use it as condition for md_stop_writes() in raid_postsuspend() doesn't look correct. 3) raid_message can set/clear the flag MD_RECOVERY_FROZEN at anytime, and if MD_RECOVERY_FROZEN is cleared while the array is suspended, new sync_thread can start unexpected. Fix above problems by using the new helper to suspend the array during suspend, also disallow raid_message() to change sync_thread status during suspend. Note that after commit f52f5c71f3d4 ("md: fix stopping sync thread"), the test shell/lvconvert-raid-reshape.sh start to hang in stop_sync_thread(), and with previous fixes, the test won't hang there anymore, however, the test will still fail and complain that ext4 is corrupted. And with this patch, the test won't hang due to stop_sync_thread() or fail due to ext4 is corrupted anymore. However, there is still a deadlock related to dm-raid456 that will be fixed in following patches. Reported-by: Mikulas Patocka Closes: https://lore.kernel.org/all/e5e8afe2-e9a8-49a2-5ab0-958d4065c55e@redhat.com/ Fixes: 1af2048a3e87 ("dm raid: fix deadlock caused by premature md_stop_writes()") Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target") Fixes: f52f5c71f3d4 ("md: fix stopping sync thread") Signed-off-by: Yu Kuai --- drivers/md/dm-raid.c | 38 +++++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index eb009d6bb03a..5ce3c6020b1b 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3240,11 +3240,12 @@ static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv) rs->md.ro = 1; rs->md.in_sync = 1; - /* Keep array frozen until resume. */ - set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); - /* Has to be held on running the array */ mddev_suspend_and_lock_nointr(&rs->md); + + /* Keep array frozen until resume. */ + md_frozen_sync_thread(&rs->md); + r = md_run(&rs->md); rs->md.in_sync = 0; /* Assume already marked dirty */ if (r) { @@ -3722,6 +3723,9 @@ static int raid_message(struct dm_target *ti, unsigned int argc, char **argv, if (!mddev->pers || !mddev->pers->sync_request) return -EINVAL; + if (test_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) + return -EBUSY; + if (!strcasecmp(argv[0], "frozen")) set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); else @@ -3791,15 +3795,31 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs)); } +static void raid_presuspend(struct dm_target *ti) +{ + struct raid_set *rs = ti->private; + + mddev_lock_nointr(&rs->md); + md_frozen_sync_thread(&rs->md); + mddev_unlock(&rs->md); +} + +static void raid_presuspend_undo(struct dm_target *ti) +{ + struct raid_set *rs = ti->private; + + mddev_lock_nointr(&rs->md); + md_unfrozen_sync_thread(&rs->md); + mddev_unlock(&rs->md); +} + static void raid_postsuspend(struct dm_target *ti) { struct raid_set *rs = ti->private; if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) { /* Writes have to be stopped before suspending to avoid deadlocks. */ - if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery)) - md_stop_writes(&rs->md); - + md_stop_writes(&rs->md); mddev_suspend(&rs->md, false); } } @@ -4012,8 +4032,6 @@ static int raid_preresume(struct dm_target *ti) } /* Check for any resize/reshape on @rs and adjust/initiate */ - /* Be prepared for mddev_resume() in raid_resume() */ - set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) { set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); mddev->resync_min = mddev->recovery_cp; @@ -4056,9 +4074,9 @@ static void raid_resume(struct dm_target *ti) rs_set_capacity(rs); mddev_lock_nointr(mddev); - clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); mddev->ro = 0; mddev->in_sync = 0; + md_unfrozen_sync_thread(mddev); mddev_unlock_and_resume(mddev); } } @@ -4074,6 +4092,8 @@ static struct target_type raid_target = { .message = raid_message, .iterate_devices = raid_iterate_devices, .io_hints = raid_io_hints, + .presuspend = raid_presuspend, + .presuspend_undo = raid_presuspend_undo, .postsuspend = raid_postsuspend, .preresume = raid_preresume, .resume = raid_resume,