From: Jan Kara <jack@suse.cz>
To: Byungchul Park <byungchul.park@lge.com>
Cc: torvalds@linux-foundation.org, damien.lemoal@opensource.wdc.com,
linux-ide@vger.kernel.org, adilger.kernel@dilger.ca,
linux-ext4@vger.kernel.org, mingo@redhat.com,
linux-kernel@vger.kernel.org, peterz@infradead.org,
will@kernel.org, tglx@linutronix.de, rostedt@goodmis.org,
joel@joelfernandes.org, sashal@kernel.org,
daniel.vetter@ffwll.ch, chris@chris-wilson.co.uk,
duyuyang@gmail.com, johannes.berg@intel.com, tj@kernel.org,
tytso@mit.edu, willy@infradead.org, david@fromorbit.com,
amir73il@gmail.com, bfields@fieldses.org,
gregkh@linuxfoundation.org, kernel-team@lge.com,
linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@kernel.org,
minchan@kernel.org, hannes@cmpxchg.org, vdavydov.dev@gmail.com,
sj@kernel.org, jglisse@redhat.com, dennis@kernel.org,
cl@linux.com, penberg@kernel.org, rientjes@google.com,
vbabka@suse.cz, ngupta@vflare.org, linux-block@vger.kernel.org,
axboe@kernel.dk, paolo.valente@linaro.org, josef@toxicpanda.com,
linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk,
jack@suse.cz, jack@suse.com, jlayton@kernel.org,
dan.j.williams@intel.com, hch@infradead.org, djwong@kernel.org,
dri-devel@lists.freedesktop.org, airlied@linux.ie,
rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com,
hamohammed.sa@gmail.com
Subject: Re: Report 2 in ext4 and journal based on v5.17-rc1
Date: Mon, 21 Feb 2022 20:02:04 +0100 [thread overview]
Message-ID: <20220221190204.q675gtsb6qhylywa@quack3.lan> (raw)
In-Reply-To: <1645096204-31670-2-git-send-email-byungchul.park@lge.com>
So I was trying to understand what this report is about for some time but
honestly I have failed...
On Thu 17-02-22 20:10:04, Byungchul Park wrote:
> [ 9.008161] ===================================================
> [ 9.008163] DEPT: Circular dependency has been detected.
> [ 9.008164] 5.17.0-rc1-00015-gb94f67143867-dirty #2 Tainted: G W
> [ 9.008166] ---------------------------------------------------
> [ 9.008167] summary
> [ 9.008167] ---------------------------------------------------
> [ 9.008168] *** DEADLOCK ***
> [ 9.008168]
> [ 9.008168] context A
> [ 9.008169] [S] (unknown)(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008171] [W] wait(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008172] [E] event(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008173]
> [ 9.008173] context B
> [ 9.008174] [S] down_write(mapping.invalidate_lock:0)
> [ 9.008175] [W] wait(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008176] [E] up_write(mapping.invalidate_lock:0)
> [ 9.008177]
> [ 9.008178] context C
> [ 9.008179] [S] (unknown)(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008180] [W] down_write(mapping.invalidate_lock:0)
> [ 9.008181] [E] event(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008181]
> [ 9.008182] [S]: start of the event context
> [ 9.008183] [W]: the wait blocked
> [ 9.008183] [E]: the event not reachable
So what situation is your tool complaining about here? Can you perhaps show
it here in more common visualization like:
TASK1 TASK2
does foo, grabs Z
does X, grabs lock Y
blocks on Z
blocks on Y
or something like that? Because I was not able to decipher this from the
report even after trying for some time...
Honza
> [ 9.008184] ---------------------------------------------------
> [ 9.008184] context A's detail
> [ 9.008185] ---------------------------------------------------
> [ 9.008186] context A
> [ 9.008186] [S] (unknown)(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008187] [W] wait(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008188] [E] event(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008189]
> [ 9.008190] [S] (unknown)(&(&journal->j_wait_transaction_locked)->dmap:0):
> [ 9.008191] (N/A)
> [ 9.008191]
> [ 9.008192] [W] wait(&(&journal->j_wait_commit)->dmap:0):
> [ 9.008193] prepare_to_wait (kernel/sched/wait.c:275)
> [ 9.008197] stacktrace:
> [ 9.008198] __schedule (kernel/sched/sched.h:1318 kernel/sched/sched.h:1616 kernel/sched/core.c:6213)
> [ 9.008200] schedule (kernel/sched/core.c:6373 (discriminator 1))
> [ 9.008201] kjournald2 (fs/jbd2/journal.c:250)
> [ 9.008203] kthread (kernel/kthread.c:377)
> [ 9.008206] ret_from_fork (arch/x86/entry/entry_64.S:301)
> [ 9.008209]
> [ 9.008209] [E] event(&(&journal->j_wait_transaction_locked)->dmap:0):
> [ 9.008210] __wake_up_common (kernel/sched/wait.c:108)
> [ 9.008212] stacktrace:
> [ 9.008213] dept_event (kernel/dependency/dept.c:2337)
> [ 9.008215] __wake_up_common (kernel/sched/wait.c:109)
> [ 9.008217] __wake_up_common_lock (./include/linux/spinlock.h:428 (discriminator 1) kernel/sched/wait.c:141 (discriminator 1))
> [ 9.008218] jbd2_journal_commit_transaction (fs/jbd2/commit.c:583)
> [ 9.008221] kjournald2 (fs/jbd2/journal.c:214 (discriminator 3))
> [ 9.008223] kthread (kernel/kthread.c:377)
> [ 9.008224] ret_from_fork (arch/x86/entry/entry_64.S:301)
> [ 9.008226] ---------------------------------------------------
> [ 9.008226] context B's detail
> [ 9.008227] ---------------------------------------------------
> [ 9.008228] context B
> [ 9.008228] [S] down_write(mapping.invalidate_lock:0)
> [ 9.008229] [W] wait(&(&journal->j_wait_transaction_locked)->dmap:0)
> [ 9.008230] [E] up_write(mapping.invalidate_lock:0)
> [ 9.008231]
> [ 9.008232] [S] down_write(mapping.invalidate_lock:0):
> [ 9.008233] ext4_da_write_begin (fs/ext4/truncate.h:21 fs/ext4/inode.c:2963)
> [ 9.008237] stacktrace:
> [ 9.008237] down_write (kernel/locking/rwsem.c:1514)
> [ 9.008239] ext4_da_write_begin (fs/ext4/truncate.h:21 fs/ext4/inode.c:2963)
> [ 9.008241] generic_perform_write (mm/filemap.c:3784)
> [ 9.008243] ext4_buffered_write_iter (fs/ext4/file.c:269)
> [ 9.008245] ext4_file_write_iter (fs/ext4/file.c:677)
> [ 9.008247] new_sync_write (fs/read_write.c:504 (discriminator 1))
> [ 9.008250] vfs_write (fs/read_write.c:590)
> [ 9.008251] ksys_write (fs/read_write.c:644)
> [ 9.008253] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
> [ 9.008255] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)
> [ 9.008258]
> [ 9.008258] [W] wait(&(&journal->j_wait_transaction_locked)->dmap:0):
> [ 9.008259] prepare_to_wait (kernel/sched/wait.c:275)
> [ 9.008261] stacktrace:
> [ 9.008261] __schedule (kernel/sched/sched.h:1318 kernel/sched/sched.h:1616 kernel/sched/core.c:6213)
> [ 9.008263] schedule (kernel/sched/core.c:6373 (discriminator 1))
> [ 9.008264] wait_transaction_locked (fs/jbd2/transaction.c:184)
> [ 9.008266] add_transaction_credits (fs/jbd2/transaction.c:248 (discriminator 3))
> [ 9.008267] start_this_handle (fs/jbd2/transaction.c:427)
> [ 9.008269] jbd2__journal_start (fs/jbd2/transaction.c:526)
> [ 9.008271] __ext4_journal_start_sb (fs/ext4/ext4_jbd2.c:105)
> [ 9.008273] ext4_truncate (fs/ext4/inode.c:4164)
> [ 9.008274] ext4_da_write_begin (./include/linux/fs.h:827 fs/ext4/truncate.h:23 fs/ext4/inode.c:2963)
> [ 9.008276] generic_perform_write (mm/filemap.c:3784)
> [ 9.008277] ext4_buffered_write_iter (fs/ext4/file.c:269)
> [ 9.008279] ext4_file_write_iter (fs/ext4/file.c:677)
> [ 9.008281] new_sync_write (fs/read_write.c:504 (discriminator 1))
> [ 9.008283] vfs_write (fs/read_write.c:590)
> [ 9.008284] ksys_write (fs/read_write.c:644)
> [ 9.008285] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
> [ 9.008287]
> [ 9.008288] [E] up_write(mapping.invalidate_lock:0):
> [ 9.008288] ext4_da_get_block_prep (fs/ext4/inode.c:1795 fs/ext4/inode.c:1829)
> [ 9.008291] ---------------------------------------------------
> [ 9.008291] context C's detail
> [ 9.008292] ---------------------------------------------------
> [ 9.008292] context C
> [ 9.008293] [S] (unknown)(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008294] [W] down_write(mapping.invalidate_lock:0)
> [ 9.008295] [E] event(&(&journal->j_wait_commit)->dmap:0)
> [ 9.008296]
> [ 9.008297] [S] (unknown)(&(&journal->j_wait_commit)->dmap:0):
> [ 9.008298] (N/A)
> [ 9.008298]
> [ 9.008299] [W] down_write(mapping.invalidate_lock:0):
> [ 9.008299] ext4_da_write_begin (fs/ext4/truncate.h:21 fs/ext4/inode.c:2963)
> [ 9.008302] stacktrace:
> [ 9.008302] down_write (kernel/locking/rwsem.c:1514)
> [ 9.008304] ext4_da_write_begin (fs/ext4/truncate.h:21 fs/ext4/inode.c:2963)
> [ 9.008305] generic_perform_write (mm/filemap.c:3784)
> [ 9.008307] ext4_buffered_write_iter (fs/ext4/file.c:269)
> [ 9.008309] ext4_file_write_iter (fs/ext4/file.c:677)
> [ 9.008311] new_sync_write (fs/read_write.c:504 (discriminator 1))
> [ 9.008312] vfs_write (fs/read_write.c:590)
> [ 9.008314] ksys_write (fs/read_write.c:644)
> [ 9.008315] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
> [ 9.008316] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)
> [ 9.008318]
> [ 9.008319] [E] event(&(&journal->j_wait_commit)->dmap:0):
> [ 9.008320] __wake_up_common (kernel/sched/wait.c:108)
> [ 9.008321] stacktrace:
> [ 9.008322] __wake_up_common (kernel/sched/wait.c:109)
> [ 9.008323] __wake_up_common_lock (./include/linux/spinlock.h:428 (discriminator 1) kernel/sched/wait.c:141 (discriminator 1))
> [ 9.008324] __jbd2_log_start_commit (fs/jbd2/journal.c:508)
> [ 9.008326] jbd2_log_start_commit (fs/jbd2/journal.c:527)
> [ 9.008327] __jbd2_journal_force_commit (fs/jbd2/journal.c:560)
> [ 9.008329] jbd2_journal_force_commit_nested (fs/jbd2/journal.c:583)
> [ 9.008331] ext4_should_retry_alloc (fs/ext4/balloc.c:670 (discriminator 3))
> [ 9.008332] ext4_da_write_begin (fs/ext4/inode.c:2965 (discriminator 1))
> [ 9.008334] generic_perform_write (mm/filemap.c:3784)
> [ 9.008335] ext4_buffered_write_iter (fs/ext4/file.c:269)
> [ 9.008337] ext4_file_write_iter (fs/ext4/file.c:677)
> [ 9.008339] new_sync_write (fs/read_write.c:504 (discriminator 1))
> [ 9.008341] vfs_write (fs/read_write.c:590)
> [ 9.008342] ksys_write (fs/read_write.c:644)
> [ 9.008343] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
> [ 9.008345] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)
> [ 9.008347] ---------------------------------------------------
> [ 9.008348] information that might be helpful
> [ 9.008348] ---------------------------------------------------
> [ 9.008349] CPU: 0 PID: 89 Comm: jbd2/sda1-8 Tainted: G W 5.17.0-rc1-00015-gb94f67143867-dirty #2
> [ 9.008352] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> [ 9.008353] Call Trace:
> [ 9.008354] <TASK>
> [ 9.008355] dump_stack_lvl (lib/dump_stack.c:107)
> [ 9.008358] print_circle (./arch/x86/include/asm/atomic.h:108 ./include/linux/atomic/atomic-instrumented.h:258 kernel/dependency/dept.c:157 kernel/dependency/dept.c:762)
> [ 9.008360] ? print_circle (kernel/dependency/dept.c:1086)
> [ 9.008362] cb_check_dl (kernel/dependency/dept.c:1104)
> [ 9.008364] bfs (kernel/dependency/dept.c:860)
> [ 9.008366] add_dep (kernel/dependency/dept.c:1423)
> [ 9.008368] do_event.isra.25 (kernel/dependency/dept.c:1651)
> [ 9.008370] ? __wake_up_common (kernel/sched/wait.c:108)
> [ 9.008372] dept_event (kernel/dependency/dept.c:2337)
> [ 9.008374] __wake_up_common (kernel/sched/wait.c:109)
> [ 9.008376] __wake_up_common_lock (./include/linux/spinlock.h:428 (discriminator 1) kernel/sched/wait.c:141 (discriminator 1))
> [ 9.008379] jbd2_journal_commit_transaction (fs/jbd2/commit.c:583)
> [ 9.008381] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:24)
> [ 9.008385] ? ret_from_fork (arch/x86/entry/entry_64.S:301)
> [ 9.008387] ? dept_enable_hardirq (./arch/x86/include/asm/current.h:15 kernel/dependency/dept.c:241 kernel/dependency/dept.c:999 kernel/dependency/dept.c:1043 kernel/dependency/dept.c:1843)
> [ 9.008389] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/irqflags.h:45 ./arch/x86/include/asm/irqflags.h:80 ./arch/x86/include/asm/irqflags.h:138 ./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194)
> [ 9.008392] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:103 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194)
> [ 9.008394] ? try_to_del_timer_sync (kernel/time/timer.c:1239)
> [ 9.008396] kjournald2 (fs/jbd2/journal.c:214 (discriminator 3))
> [ 9.008398] ? prepare_to_wait_exclusive (kernel/sched/wait.c:431)
> [ 9.008400] ? commit_timeout (fs/jbd2/journal.c:173)
> [ 9.008402] kthread (kernel/kthread.c:377)
> [ 9.008404] ? kthread_complete_and_exit (kernel/kthread.c:332)
> [ 9.008407] ret_from_fork (arch/x86/entry/entry_64.S:301)
> [ 9.008410] </TASK>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
next prev parent reply other threads:[~2022-02-21 19:02 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-17 10:57 [PATCH 00/16] DEPT(Dependency Tracker) Byungchul Park
2022-02-17 10:57 ` [PATCH 01/16] llist: Move llist_{head,node} definition to types.h Byungchul Park
2022-02-17 10:57 ` [PATCH 02/16] dept: Implement Dept(Dependency Tracker) Byungchul Park
2022-02-17 15:54 ` Steven Rostedt
2022-02-17 17:36 ` Steven Rostedt
2022-02-18 6:09 ` Byungchul Park
2022-02-17 19:46 ` kernel test robot
2022-02-17 19:46 ` kernel test robot
2022-02-17 10:57 ` [PATCH 03/16] dept: Embed Dept data in Lockdep Byungchul Park
2022-02-17 10:57 ` [PATCH 04/16] dept: Apply Dept to spinlock Byungchul Park
2022-02-17 10:57 ` [PATCH 05/16] dept: Apply Dept to mutex families Byungchul Park
2022-02-17 10:57 ` [PATCH 06/16] dept: Apply Dept to rwlock Byungchul Park
2022-02-17 10:57 ` [PATCH 07/16] dept: Apply Dept to wait_for_completion()/complete() Byungchul Park
2022-02-17 19:46 ` kernel test robot
2022-02-17 10:57 ` [PATCH 08/16] dept: Apply Dept to seqlock Byungchul Park
2022-02-17 10:57 ` [PATCH 09/16] dept: Apply Dept to rwsem Byungchul Park
2022-02-17 10:57 ` [PATCH 10/16] dept: Add proc knobs to show stats and dependency graph Byungchul Park
2022-02-17 15:55 ` Steven Rostedt
2022-02-17 10:57 ` [PATCH 11/16] dept: Introduce split map concept and new APIs for them Byungchul Park
2022-02-17 10:57 ` [PATCH 12/16] dept: Apply Dept to wait/event of PG_{locked,writeback} Byungchul Park
2022-02-17 10:57 ` [PATCH 13/16] dept: Apply SDT to swait Byungchul Park
2022-02-17 10:57 ` [PATCH 14/16] dept: Apply SDT to wait(waitqueue) Byungchul Park
2022-02-17 10:57 ` [PATCH 15/16] locking/lockdep, cpu/hotplus: Use a weaker annotation in AP thread Byungchul Park
2022-02-17 10:57 ` [PATCH 16/16] dept: Distinguish each syscall context from another Byungchul Park
2022-02-17 11:10 ` Report 1 in ext4 and journal based on v5.17-rc1 Byungchul Park
2022-02-17 11:10 ` Report 2 " Byungchul Park
2022-02-21 19:02 ` Jan Kara [this message]
2022-02-23 0:35 ` Byungchul Park
2022-02-23 14:48 ` Jan Kara
2022-02-24 1:11 ` Byungchul Park
2022-02-24 10:22 ` Jan Kara
2022-02-28 9:28 ` Byungchul Park
2022-02-28 10:14 ` Jan Kara
2022-02-28 21:25 ` Theodore Ts'o
2022-03-03 1:36 ` Byungchul Park
2022-03-03 1:00 ` Byungchul Park
2022-03-03 2:32 ` Theodore Ts'o
2022-03-03 5:23 ` Byungchul Park
2022-03-03 14:36 ` Theodore Ts'o
2022-03-04 0:42 ` Byungchul Park
2022-03-05 3:26 ` Theodore Ts'o
2022-03-05 14:15 ` Byungchul Park
2022-03-05 15:05 ` Joel Fernandes
2022-03-07 2:43 ` Byungchul Park
2022-03-04 3:20 ` Byungchul Park
2022-03-05 3:40 ` Theodore Ts'o
2022-03-05 14:55 ` Byungchul Park
2022-03-05 15:12 ` Reimar Döffinger
2022-03-06 3:30 ` Theodore Ts'o
2022-03-06 10:51 ` Byungchul Park
2022-03-06 14:19 ` Theodore Ts'o
2022-03-10 1:45 ` Byungchul Park
2022-03-03 9:54 ` Jan Kara
2022-03-04 1:56 ` Byungchul Park
2022-02-17 13:27 ` Report 1 " Matthew Wilcox
2022-02-18 0:41 ` Byungchul Park
2022-02-22 8:27 ` Jan Kara
2022-02-23 1:40 ` Byungchul Park
2022-02-23 3:30 ` Byungchul Park
2022-02-17 15:51 ` [PATCH 00/16] DEPT(Dependency Tracker) Theodore Ts'o
2022-02-17 17:00 ` Steven Rostedt
2022-02-17 17:06 ` Matthew Wilcox
2022-02-19 10:05 ` Byungchul Park
2022-02-18 4:19 ` Theodore Ts'o
2022-02-19 10:34 ` Byungchul Park
2022-02-19 10:18 ` Byungchul Park
2022-02-19 9:54 ` Byungchul Park
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