From patchwork Wed Apr 17 17:49:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mikulas Patocka X-Patchwork-Id: 13633695 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 1FFD2171669 for ; Wed, 17 Apr 2024 17:49:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713376165; cv=none; b=UMzVqDxIR8MtwL8X/dm34P75yrTmeYL2V7uaJN0PtLCd0bwuIviVTGa1EZ6F8n7WUKYSHluLrnDAjkyBhGsqeS4zzg767XPmiiZqTVTD3w5lfB9Iks9XqS48HIrHnqWUgn9MhywU9VHnZLTk3VFtSqBVHZ6UT56pnP3TpnXx7cU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713376165; c=relaxed/simple; bh=FYolpYZ25eTFYqMkR6yEsWu9xJyTtvfoFSQkRdJikcI=; h=Date:From:To:cc:Subject:Message-ID:MIME-Version:Content-Type; b=gKyO/5FTunNeS5BeaKsxZ9exmHa4BCFfTjzZkINL2BLsofykfYYSctADsR0hC5rsN3EDsquj3XI0ocXE2wilq7/ecHZ8A+oCuRw6L0mtDLbyvS7pEN5cQriWHdAAK4N2cYHu50UgsOBY06nsEftyoocarc8X3EVjOKbCrcKh0Xs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=MpKJo7vG; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MpKJo7vG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1713376163; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=lRV892maf5KBkoWbV+bN/G5QeBDW5WP72bhpiy5MQpk=; b=MpKJo7vGh3pUtHLcX5pUHZ1uKJtwzTjlu338dA8DRTn5K5+Sr7yroDKV8cn5K9Yyb9AbqO M/S8el4WarsYtFPcdzPC2nIaGcerXdY4CpeY1RwgwZU+vYyyNsYo6Xt65b+7oNEljrDpHK 9zUZSBM/i40rIXx4PUbv/exGk2xWhjQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-283-cUS9pHqbO16ngFt4bsFguQ-1; Wed, 17 Apr 2024 13:49:18 -0400 X-MC-Unique: cUS9pHqbO16ngFt4bsFguQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1482A18A8261; Wed, 17 Apr 2024 17:49:18 +0000 (UTC) Received: from file1-rdu.file-001.prod.rdu2.dc.redhat.com (unknown [10.11.5.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C25C8400EAE; Wed, 17 Apr 2024 17:49:17 +0000 (UTC) Received: by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix, from userid 12668) id A6DF630C2BF7; Wed, 17 Apr 2024 17:49:17 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix) with ESMTP id A30823FD7A; Wed, 17 Apr 2024 19:49:17 +0200 (CEST) Date: Wed, 17 Apr 2024 19:49:17 +0200 (CEST) From: Mikulas Patocka To: Mike Snitzer , Jens Axboe , Damien Le Moal , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long cc: Guangwu Zhang , dm-devel@lists.linux.dev, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/2] completion: move blk_wait_io to kernel/sched/completion.c Message-ID: <31b118f3-bc8d-b18b-c4b9-e57d74a73f@redhat.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 The block layer has a function blk_wait_io - it works like wait_for_completion_io, except that it doesn't warn if the wait takes too long. This commit renames the function to wait_for_completion_long_io and moves it to kernel/sched/completion.c so that other kernel subsystems can use it. It will be needed by the dm-io subsystem. Signed-off-by: Mikulas Patocka Reviewed-by: Mikulas Patocka --- block/bio.c | 2 +- block/blk-mq.c | 2 +- block/blk.h | 12 ------------ include/linux/completion.h | 1 + kernel/sched/completion.c | 20 ++++++++++++++++++++ 5 files changed, 23 insertions(+), 14 deletions(-) Index: linux-2.6/block/blk.h =================================================================== --- linux-2.6.orig/block/blk.h 2024-04-17 19:41:14.000000000 +0200 +++ linux-2.6/block/blk.h 2024-04-17 19:41:14.000000000 +0200 @@ -72,18 +72,6 @@ static inline int bio_queue_enter(struct return __bio_queue_enter(q, bio); } -static inline void blk_wait_io(struct completion *done) -{ - /* Prevent hang_check timer from firing at us during very long I/O */ - unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2; - - if (timeout) - while (!wait_for_completion_io_timeout(done, timeout)) - ; - else - wait_for_completion_io(done); -} - #define BIO_INLINE_VECS 4 struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs, gfp_t gfp_mask); Index: linux-2.6/include/linux/completion.h =================================================================== --- linux-2.6.orig/include/linux/completion.h 2024-04-17 19:41:14.000000000 +0200 +++ linux-2.6/include/linux/completion.h 2024-04-17 19:41:14.000000000 +0200 @@ -112,6 +112,7 @@ extern long wait_for_completion_interrup struct completion *x, unsigned long timeout); extern long wait_for_completion_killable_timeout( struct completion *x, unsigned long timeout); +extern void wait_for_completion_long_io(struct completion *x); extern bool try_wait_for_completion(struct completion *x); extern bool completion_done(struct completion *x); Index: linux-2.6/block/bio.c =================================================================== --- linux-2.6.orig/block/bio.c 2024-04-17 19:41:14.000000000 +0200 +++ linux-2.6/block/bio.c 2024-04-17 19:41:14.000000000 +0200 @@ -1378,7 +1378,7 @@ int submit_bio_wait(struct bio *bio) bio->bi_end_io = submit_bio_wait_endio; bio->bi_opf |= REQ_SYNC; submit_bio(bio); - blk_wait_io(&done); + wait_for_completion_long_io(&done); return blk_status_to_errno(bio->bi_status); } Index: linux-2.6/block/blk-mq.c =================================================================== --- linux-2.6.orig/block/blk-mq.c 2024-04-17 19:41:14.000000000 +0200 +++ linux-2.6/block/blk-mq.c 2024-04-17 19:41:14.000000000 +0200 @@ -1407,7 +1407,7 @@ blk_status_t blk_execute_rq(struct reque if (blk_rq_is_poll(rq)) blk_rq_poll_completion(rq, &wait.done); else - blk_wait_io(&wait.done); + wait_for_completion_long_io(&wait.done); return wait.ret; } Index: linux-2.6/kernel/sched/completion.c =================================================================== --- linux-2.6.orig/kernel/sched/completion.c 2024-04-17 19:41:14.000000000 +0200 +++ linux-2.6/kernel/sched/completion.c 2024-04-17 19:41:14.000000000 +0200 @@ -290,6 +290,26 @@ wait_for_completion_killable_timeout(str EXPORT_SYMBOL(wait_for_completion_killable_timeout); /** + * wait_for_completion_long_io - waits for completion of a task + * @x: holds the state of this particular completion + * + * This is like wait_for_completion_io, but it doesn't warn if the wait takes + * too long. + */ +void wait_for_completion_long_io(struct completion *x) +{ + /* Prevent hang_check timer from firing at us during very long I/O */ + unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2; + + if (timeout) + while (!wait_for_completion_io_timeout(x, timeout)) + ; + else + wait_for_completion_io(x); +} +EXPORT_SYMBOL(wait_for_completion_long_io); + +/** * try_wait_for_completion - try to decrement a completion without blocking * @x: completion structure * From patchwork Wed Apr 17 17:51:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mikulas Patocka X-Patchwork-Id: 13633697 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 A005C171671 for ; Wed, 17 Apr 2024 17:51:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713376276; cv=none; b=FynGCgyt0voOecCZ6/0Hq7lKxx4fdRCoe9Cwb42nHwbYzjixq2HpQpyjXf8InszAa7xiKp71j6WQeYIIJfWuG8vsJo6FQa8k32F4DsTUPxL1JcyL363QkUUhlzG89S2iGlflOV1wLg5jhxFyghnoh2sniUS5Ra/RJigAPqOp24E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713376276; c=relaxed/simple; bh=mEWPo64/cqVvVE5N5PI7TzK6kqyhCqwo5a2U4Vz8R1I=; h=Date:From:To:cc:Subject:Message-ID:MIME-Version:Content-Type; b=s3IxdbaMl3s6TlTMcnauMJLk1D/82ifk4hdpgjwh+seEbfZNWOcpuIve+Z4I91A3GUD1Cza+Pd3fFh4FFvEbRaj5xuqNVp7L23ShTJyaDuCwzbfZH5BhY0ssMLEsUEVp1tfbo5Q300ENiO5szR/O8sDGSe91fk7s0VSAff+JtMU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=di7Cy8Om; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="di7Cy8Om" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1713376272; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=kujO86Jl3C4sFlf0wfnUMZttB5N1ylWd1xY1DJNRkI0=; b=di7Cy8OmUyQkfuX03qUwsX1ZL1hY9x0kMZEqbSDNMvpM3aWIL5HDoOZZYEKdY78O9OGcgo CUmNNTIsqz8WCQ4+U1gHnvIwkhedO+OBrFmTHgCZz56ZLB9SMFvdiN4z1mEfVTsd6+Y3rX GrVP34+oBmROH8CZiJDVsNqnNaPNZd8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-252-2KCdiRelO4OyUP-a8xoxTA-1; Wed, 17 Apr 2024 13:51:09 -0400 X-MC-Unique: 2KCdiRelO4OyUP-a8xoxTA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CC621812C55; Wed, 17 Apr 2024 17:51:08 +0000 (UTC) Received: from file1-rdu.file-001.prod.rdu2.dc.redhat.com (unknown [10.11.5.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8B7CC35430; Wed, 17 Apr 2024 17:51:08 +0000 (UTC) Received: by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix, from userid 12668) id 751F330C2BF7; Wed, 17 Apr 2024 17:51:08 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix) with ESMTP id 7190E3FD7A; Wed, 17 Apr 2024 19:51:08 +0200 (CEST) Date: Wed, 17 Apr 2024 19:51:08 +0200 (CEST) From: Mikulas Patocka To: Mike Snitzer , Jens Axboe , Damien Le Moal , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long cc: Guangwu Zhang , dm-devel@lists.linux.dev, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] dm-io: don't warn if flush takes too long time Message-ID: Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 There was reported hang warning when using dm-integrity on the top of loop device on XFS on a rotational disk. The warning was triggered because flush on the loop device was too slow. There's no easy way to reduce the latency, so I made a commit that shuts the warning up. This commit replaces wait_for_completion_io with wait_for_completion_long_io, so that the warning is avoided. [ 1352.586981] INFO: task kworker/1:2:14820 blocked for more than 120 seconds. [ 1352.593951] Not tainted 4.18.0-552.el8_10.x86_64 #1 [ 1352.599358] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1352.607202] Call Trace: [ 1352.609670] __schedule+0x2d1/0x870 [ 1352.613173] ? update_load_avg+0x7e/0x710 [ 1352.617193] ? update_load_avg+0x7e/0x710 [ 1352.621214] schedule+0x55/0xf0 [ 1352.624371] schedule_timeout+0x281/0x320 [ 1352.628393] ? __schedule+0x2d9/0x870 [ 1352.632065] io_schedule_timeout+0x19/0x40 [ 1352.636176] wait_for_completion_io+0x96/0x100 [ 1352.640639] sync_io+0xcc/0x120 [dm_mod] [ 1352.644592] dm_io+0x209/0x230 [dm_mod] [ 1352.648436] ? bit_wait_timeout+0xa0/0xa0 [ 1352.652461] ? vm_next_page+0x20/0x20 [dm_mod] [ 1352.656924] ? km_get_page+0x60/0x60 [dm_mod] [ 1352.661298] dm_bufio_issue_flush+0xa0/0xd0 [dm_bufio] [ 1352.666448] dm_bufio_write_dirty_buffers+0x1a0/0x1e0 [dm_bufio] [ 1352.672462] dm_integrity_flush_buffers+0x32/0x140 [dm_integrity] [ 1352.678567] ? lock_timer_base+0x67/0x90 [ 1352.682505] ? __timer_delete.part.36+0x5c/0x90 [ 1352.687050] integrity_commit+0x31a/0x330 [dm_integrity] [ 1352.692368] ? __switch_to+0x10c/0x430 [ 1352.696131] process_one_work+0x1d3/0x390 [ 1352.700152] ? process_one_work+0x390/0x390 [ 1352.704348] worker_thread+0x30/0x390 [ 1352.708019] ? process_one_work+0x390/0x390 [ 1352.712214] kthread+0x134/0x150 [ 1352.715459] ? set_kthread_struct+0x50/0x50 [ 1352.719659] ret_from_fork+0x1f/0x40 Signed-off-by: Mikulas Patocka --- drivers/md/dm-io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-2.6/drivers/md/dm-io.c =================================================================== --- linux-2.6.orig/drivers/md/dm-io.c 2024-04-17 19:43:07.000000000 +0200 +++ linux-2.6/drivers/md/dm-io.c 2024-04-17 19:43:07.000000000 +0200 @@ -450,7 +450,7 @@ static int sync_io(struct dm_io_client * dispatch_io(opf, num_regions, where, dp, io, 1, ioprio); - wait_for_completion_io(&sio.wait); + wait_for_completion_long_io(&sio.wait); if (error_bits) *error_bits = sio.error_bits;