| Message ID | 20211019120834.595160-3-axboe@kernel.dk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] block: change plugging to use a singly linked list | expand |
On Tue, Oct 19, 2021 at 06:08:34AM -0600, Jens Axboe wrote: > If we have just one queue type in the plug list, then we can extend our > direct issue to cover a full plug list as well. I don't think this description matches what the code does. My impression of what the code does it: If a plug only has requests for a single queue, and that queue does not use an I/O scheduler, we can just issue the list of requests directly from the plug. Otherwise looks good: Reviewed-by: Christoph Hellwig <hch@lst.de>
On 10/19/21 7:36 AM, Christoph Hellwig wrote: > On Tue, Oct 19, 2021 at 06:08:34AM -0600, Jens Axboe wrote: >> If we have just one queue type in the plug list, then we can extend our >> direct issue to cover a full plug list as well. > > I don't think this description matches what the code does. My impression > of what the code does it: > > If a plug only has requests for a single queue, and that queue does not > use an I/O scheduler, we can just issue the list of requests directly > from the plug. > > Otherwise looks good: > > Reviewed-by: Christoph Hellwig <hch@lst.de> I'll expand it a bit, that is what I was trying to say, but it just became too brief.
On Oct 19, 2021 / 06:08, Jens Axboe wrote: > If we have just one queue type in the plug list, then we can extend our > direct issue to cover a full plug list as well. > > Signed-off-by: Jens Axboe <axboe@kernel.dk> Hi Jens, I tried out for-next branch and observed A WARNING "do not call blocking ops when !TASK_RUNNING" [1]. Reverting this patch from the for-next branch, the warning disappears. The warning was triggered when mkfs.xfs is run for memory backed null_blk devices with "none" scheduler. The commands below recreates it. # modprobe null_blk nr_devices=0 # mkdir /sys/kernel/config/nullb/nullb0 # declare sysfs=/sys/kernel/config/nullb/nullb0 # echo 1 > "${sysfs}"/memory_backed # echo 1 > "${sysfs}"/power # echo none > /sys/block/nullb0/queue/scheduler # mkfs.xfs /dev/nullb0 Referring the call stack printed, I walked through the function calls. In __blkdev_direct_IO_simple(), task state is set UNINTERRUPTIBLE. Way down to might_sleep_if() called from null_queue_rq(), it is warned that the task state is not RUNNING. This patch adds blk_mq_plug_issue_direct() call in blk_mq_flush_plug_list(), then the call path was linked from __blkdev_direct_IO_simple() to null_queue_rq(). __blkdev_direct_IO_simple() block/fops.c set_current_state(TASK_UNINTERRUPTIBLE) ... current->__state = TASK_UNINTERRUPTIBLE blk_io_schedule() io_schedule_timeout() kernel/sched/core.c io_schedule_prepare() blk_schedule_flush_plug() include/linux/blkdev.h blk_flush_plug_list() block/blk-core.c blk_mq_flush_plug_list() blk_mq_flush_plug_list() block/blk-mq.c ... this patch added call to blk_mq_plug_issue_direct() blk_mq_plug_issue_direct() blk_mq_reqeust_issue_directly() __blk_mq_try_issue_directly() __blk_mq_issue_directly() q->mq_ops->queue_rq() null_queue_rq() drivers/block/null_blk/main.c might_sleep_if(flags & BLK_MQ_F_BLOCKING) include/linux/kernel.h might_sleep() __might_sleep() kernel/sched/core.c ... current->__state != TASK_RUNNING (WARN_ONCE) So far, I can't think of a good solution for this warning. Any idea? [1] [60501.340746] null_blk: module loaded [60519.303106] ------------[ cut here ]------------ [60519.308485] do not call blocking ops when !TASK_RUNNING; state=2 set at [<000000005ba5e596>] __blkdev_direct_IO_simple+0x3f8/0x6f0 [60519.320943] WARNING: CPU: 2 PID: 8929 at kernel/sched/core.c:9486 __might_sleep+0x124/0x160 [60519.330001] Modules linked in: null_blk xfs dm_zoned xt_conntrack nf_nat_tftp nf_conntrack_tftp bridge stp llc nft_objref nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_tables ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw iptable_security ip_set nfnetlink ebtable_filter rfkill ebtables target_core_user target_core_mod ip6table_filter ip6_tables iptable_filter sunrpc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass iTCO_wdt intel_pmc_bxt iTCO_vendor_support rapl intel_cstate intel_uncore pcspkr joydev ipmi_ssif i2c_i801 lpc_ich i2c_smbus ses enclosure mei_me mei ioatdma wmi acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler acpi_pad acpi_power_meter zram ip_tables ast [60519.330166] drm_vram_helper drm_kms_helper cec drm_ttm_helper crct10dif_pclmul ttm crc32_pclmul crc32c_intel drm ghash_clmulni_intel igb mpt3sas nvme dca nvme_core i2c_algo_bit raid_class scsi_transport_sas fuse [last unloaded: null_blk] [60519.438458] CPU: 2 PID: 8929 Comm: mkfs.xfs Not tainted 5.15.0-rc6+ #11 [60519.445781] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015 [60519.453893] RIP: 0010:__might_sleep+0x124/0x160 [60519.459139] Code: 48 8d bb 98 2c 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 75 31 48 8b 93 98 2c 00 00 44 89 f6 48 c7 c7 e0 f2 88 8a e8 04 eb f9 01 <0f> 0b e9 6d ff ff ff e8 60 d1 66 00 e9 1c ff ff ff e8 66 d1 66 00 [60519.478594] RSP: 0018:ffff8882707ef5a8 EFLAGS: 00010286 [60519.484533] RAX: 0000000000000000 RBX: ffff888125cbb280 RCX: 0000000000000000 [60519.492379] RDX: 0000000000000004 RSI: 0000000000000008 RDI: ffffed104e0fdeab [60519.500216] RBP: ffffffffc16122c0 R08: 0000000000000001 R09: ffff8888114ad587 [60519.508052] R10: ffffed1102295ab0 R11: 0000000000000001 R12: 0000000000000618 [60519.515886] R13: 0000000000000000 R14: 0000000000000002 R15: ffff88813160a000 [60519.523721] FS: 00007fd79959b400(0000) GS:ffff888811480000(0000) knlGS:0000000000000000 [60519.532509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [60519.538963] CR2: 000055bf4e3dc000 CR3: 000000029e904005 CR4: 00000000001706e0 [60519.546803] Call Trace: [60519.549976] null_queue_rq+0x3ee/0x6b0 [null_blk] [60519.555407] __blk_mq_try_issue_directly+0x433/0x680 [60519.561085] ? __submit_bio+0x63a/0x780 [60519.565636] ? __blk_mq_get_driver_tag+0x9a0/0x9a0 [60519.571144] blk_mq_flush_plug_list+0x5f6/0xc40 [60519.576387] ? iov_iter_get_pages_alloc+0xf50/0xf50 [60519.581980] ? find_held_lock+0x2c/0x110 [60519.586618] ? blk_mq_insert_requests+0x440/0x440 [60519.592044] ? __blkdev_direct_IO_simple+0x3f8/0x6f0 [60519.597719] blk_flush_plug_list+0x28f/0x410 [60519.602710] ? blk_start_plug_nr_ios+0x270/0x270 [60519.608039] ? __blkdev_direct_IO_simple+0x3f8/0x6f0 [60519.613713] io_schedule_timeout+0xcc/0x150 [60519.618621] __blkdev_direct_IO_simple+0x475/0x6f0 [60519.624126] ? blkdev_llseek+0xc0/0xc0 [60519.628598] ? blkdev_get_block+0xd0/0xd0 [60519.633320] ? filemap_check_errors+0xe0/0xe0 [60519.638391] ? find_held_lock+0x2c/0x110 [60519.643024] ? lock_release+0x1d4/0x690 [60519.647574] blkdev_direct_IO+0x9b2/0x1110 [60519.652389] ? filemap_check_errors+0x56/0xe0 [60519.657455] ? add_watch_to_object+0xa0/0x6e0 [60519.662524] ? blkdev_bio_end_io+0x490/0x490 [60519.667518] generic_file_direct_write+0x1a9/0x4a0 [60519.673026] __generic_file_write_iter+0x1fa/0x480 [60519.678526] ? lock_is_held_type+0xe0/0x110 [60519.683420] blkdev_write_iter+0x319/0x5a0 [60519.688231] ? blkdev_open+0x260/0x260 [60519.692690] ? lock_downgrade+0x6b0/0x6b0 [60519.697412] ? do_raw_spin_unlock+0x55/0x1f0 [60519.702392] new_sync_write+0x359/0x5e0 [60519.706941] ? new_sync_read+0x5d0/0x5d0 [60519.711582] ? __cond_resched+0x15/0x30 [60519.716124] ? inode_security+0x56/0xf0 [60519.720688] vfs_write+0x5e4/0x8e0 [60519.724805] __x64_sys_pwrite64+0x17c/0x1d0 [60519.729698] ? vfs_write+0x8e0/0x8e0 [60519.733982] ? syscall_enter_from_user_mode+0x21/0x70 [60519.739747] do_syscall_64+0x3b/0x90 [60519.744037] entry_SYSCALL_64_after_hwframe+0x44/0xae [60519.749796] RIP: 0033:0x7fd7997c125a [60519.754088] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 12 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 [60519.773543] RSP: 002b:00007ffe8d456718 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 [60519.781816] RAX: ffffffffffffffda RBX: 00007ffe8d456e10 RCX: 00007fd7997c125a [60519.789656] RDX: 0000000000020000 RSI: 000055bf4e3bd600 RDI: 0000000000000004 [60519.797494] RBP: 0000000000020000 R08: 000055bf4e3bd600 R09: 00007fd79975fa60 [60519.805333] R10: 00000003fffe0000 R11: 0000000000000246 R12: 000055bf4e3b9710 [60519.813172] R13: 0000000000000004 R14: 000055bf4e3bd600 R15: 0000000000001000 [60519.821028] irq event stamp: 20385 [60519.825139] hardirqs last enabled at (20395): [<ffffffff883481e0>] __up_console_sem+0x60/0x70 [60519.834455] hardirqs last disabled at (20404): [<ffffffff883481c5>] __up_console_sem+0x45/0x70 [60519.843763] softirqs last enabled at (20372): [<ffffffff881e6a7c>] __irq_exit_rcu+0x19c/0x200 [60519.853079] softirqs last disabled at (20367): [<ffffffff881e6a7c>] __irq_exit_rcu+0x19c/0x200 [60519.862389] ---[ end trace be9623465002e439 ]---
On 10/25/21 11:20 PM, Shinichiro Kawasaki wrote: > On Oct 19, 2021 / 06:08, Jens Axboe wrote: >> If we have just one queue type in the plug list, then we can extend our >> direct issue to cover a full plug list as well. >> >> Signed-off-by: Jens Axboe <axboe@kernel.dk> > > Hi Jens, I tried out for-next branch and observed A WARNING "do not call > blocking ops when !TASK_RUNNING" [1]. Reverting this patch from the for-next > branch, the warning disappears. The warning was triggered when mkfs.xfs is > run for memory backed null_blk devices with "none" scheduler. The commands below > recreates it. > > # modprobe null_blk nr_devices=0 > # mkdir /sys/kernel/config/nullb/nullb0 > # declare sysfs=/sys/kernel/config/nullb/nullb0 > # echo 1 > "${sysfs}"/memory_backed > # echo 1 > "${sysfs}"/power > # echo none > /sys/block/nullb0/queue/scheduler > # mkfs.xfs /dev/nullb0 > > > Referring the call stack printed, I walked through the function calls. In > __blkdev_direct_IO_simple(), task state is set UNINTERRUPTIBLE. Way > down to might_sleep_if() called from null_queue_rq(), it is warned that > the task state is not RUNNING. This patch adds blk_mq_plug_issue_direct() > call in blk_mq_flush_plug_list(), then the call path was linked from > __blkdev_direct_IO_simple() to null_queue_rq(). > > __blkdev_direct_IO_simple() block/fops.c > set_current_state(TASK_UNINTERRUPTIBLE) ... current->__state = TASK_UNINTERRUPTIBLE > blk_io_schedule() > io_schedule_timeout() kernel/sched/core.c > io_schedule_prepare() > blk_schedule_flush_plug() include/linux/blkdev.h > blk_flush_plug_list() block/blk-core.c > blk_mq_flush_plug_list() > blk_mq_flush_plug_list() block/blk-mq.c ... this patch added call to blk_mq_plug_issue_direct() > blk_mq_plug_issue_direct() > blk_mq_reqeust_issue_directly() > __blk_mq_try_issue_directly() > __blk_mq_issue_directly() > q->mq_ops->queue_rq() > null_queue_rq() drivers/block/null_blk/main.c > might_sleep_if(flags & BLK_MQ_F_BLOCKING) include/linux/kernel.h > might_sleep() > __might_sleep() kernel/sched/core.c ... current->__state != TASK_RUNNING (WARN_ONCE) > > So far, I can't think of a good solution for this warning. Any idea? > > > [1] > > [60501.340746] null_blk: module loaded > [60519.303106] ------------[ cut here ]------------ > [60519.308485] do not call blocking ops when !TASK_RUNNING; state=2 set at [<000000005ba5e596>] __blkdev_direct_IO_simple+0x3f8/0x6f0 > [60519.320943] WARNING: CPU: 2 PID: 8929 at kernel/sched/core.c:9486 __might_sleep+0x124/0x160 > [60519.330001] Modules linked in: null_blk xfs dm_zoned xt_conntrack nf_nat_tftp nf_conntrack_tftp bridge stp llc nft_objref nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_tables ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw iptable_security ip_set nfnetlink ebtable_filter rfkill ebtables target_core_user target_core_mod ip6table_filter ip6_tables iptable_filter sunrpc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass iTCO_wdt intel_pmc_bxt iTCO_vendor_support rapl intel_cstate intel_uncore pcspkr joydev ipmi_ssif i2c_i801 lpc_ich i2c_smbus ses enclosure mei_me mei ioatdma wmi acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler acpi_pad acpi_power_meter zram ip_tables ast > [60519.330166] drm_vram_helper drm_kms_helper cec drm_ttm_helper crct10dif_pclmul ttm crc32_pclmul crc32c_intel drm ghash_clmulni_intel igb mpt3sas nvme dca nvme_core i2c_algo_bit raid_class scsi_transport_sas fuse [last unloaded: null_blk] > [60519.438458] CPU: 2 PID: 8929 Comm: mkfs.xfs Not tainted 5.15.0-rc6+ #11 > [60519.445781] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015 > [60519.453893] RIP: 0010:__might_sleep+0x124/0x160 > [60519.459139] Code: 48 8d bb 98 2c 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 75 31 48 8b 93 98 2c 00 00 44 89 f6 48 c7 c7 e0 f2 88 8a e8 04 eb f9 01 <0f> 0b e9 6d ff ff ff e8 60 d1 66 00 e9 1c ff ff ff e8 66 d1 66 00 > [60519.478594] RSP: 0018:ffff8882707ef5a8 EFLAGS: 00010286 > [60519.484533] RAX: 0000000000000000 RBX: ffff888125cbb280 RCX: 0000000000000000 > [60519.492379] RDX: 0000000000000004 RSI: 0000000000000008 RDI: ffffed104e0fdeab > [60519.500216] RBP: ffffffffc16122c0 R08: 0000000000000001 R09: ffff8888114ad587 > [60519.508052] R10: ffffed1102295ab0 R11: 0000000000000001 R12: 0000000000000618 > [60519.515886] R13: 0000000000000000 R14: 0000000000000002 R15: ffff88813160a000 > [60519.523721] FS: 00007fd79959b400(0000) GS:ffff888811480000(0000) knlGS:0000000000000000 > [60519.532509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [60519.538963] CR2: 000055bf4e3dc000 CR3: 000000029e904005 CR4: 00000000001706e0 > [60519.546803] Call Trace: > [60519.549976] null_queue_rq+0x3ee/0x6b0 [null_blk] > [60519.555407] __blk_mq_try_issue_directly+0x433/0x680 > [60519.561085] ? __submit_bio+0x63a/0x780 > [60519.565636] ? __blk_mq_get_driver_tag+0x9a0/0x9a0 > [60519.571144] blk_mq_flush_plug_list+0x5f6/0xc40 > [60519.576387] ? iov_iter_get_pages_alloc+0xf50/0xf50 > [60519.581980] ? find_held_lock+0x2c/0x110 > [60519.586618] ? blk_mq_insert_requests+0x440/0x440 > [60519.592044] ? __blkdev_direct_IO_simple+0x3f8/0x6f0 > [60519.597719] blk_flush_plug_list+0x28f/0x410 > [60519.602710] ? blk_start_plug_nr_ios+0x270/0x270 > [60519.608039] ? __blkdev_direct_IO_simple+0x3f8/0x6f0 > [60519.613713] io_schedule_timeout+0xcc/0x150 > [60519.618621] __blkdev_direct_IO_simple+0x475/0x6f0 > [60519.624126] ? blkdev_llseek+0xc0/0xc0 > [60519.628598] ? blkdev_get_block+0xd0/0xd0 > [60519.633320] ? filemap_check_errors+0xe0/0xe0 > [60519.638391] ? find_held_lock+0x2c/0x110 > [60519.643024] ? lock_release+0x1d4/0x690 > [60519.647574] blkdev_direct_IO+0x9b2/0x1110 > [60519.652389] ? filemap_check_errors+0x56/0xe0 > [60519.657455] ? add_watch_to_object+0xa0/0x6e0 > [60519.662524] ? blkdev_bio_end_io+0x490/0x490 > [60519.667518] generic_file_direct_write+0x1a9/0x4a0 > [60519.673026] __generic_file_write_iter+0x1fa/0x480 > [60519.678526] ? lock_is_held_type+0xe0/0x110 > [60519.683420] blkdev_write_iter+0x319/0x5a0 > [60519.688231] ? blkdev_open+0x260/0x260 > [60519.692690] ? lock_downgrade+0x6b0/0x6b0 > [60519.697412] ? do_raw_spin_unlock+0x55/0x1f0 > [60519.702392] new_sync_write+0x359/0x5e0 > [60519.706941] ? new_sync_read+0x5d0/0x5d0 > [60519.711582] ? __cond_resched+0x15/0x30 > [60519.716124] ? inode_security+0x56/0xf0 > [60519.720688] vfs_write+0x5e4/0x8e0 > [60519.724805] __x64_sys_pwrite64+0x17c/0x1d0 > [60519.729698] ? vfs_write+0x8e0/0x8e0 > [60519.733982] ? syscall_enter_from_user_mode+0x21/0x70 > [60519.739747] do_syscall_64+0x3b/0x90 > [60519.744037] entry_SYSCALL_64_after_hwframe+0x44/0xae > [60519.749796] RIP: 0033:0x7fd7997c125a > [60519.754088] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 12 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 > [60519.773543] RSP: 002b:00007ffe8d456718 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 > [60519.781816] RAX: ffffffffffffffda RBX: 00007ffe8d456e10 RCX: 00007fd7997c125a > [60519.789656] RDX: 0000000000020000 RSI: 000055bf4e3bd600 RDI: 0000000000000004 > [60519.797494] RBP: 0000000000020000 R08: 000055bf4e3bd600 R09: 00007fd79975fa60 > [60519.805333] R10: 00000003fffe0000 R11: 0000000000000246 R12: 000055bf4e3b9710 > [60519.813172] R13: 0000000000000004 R14: 000055bf4e3bd600 R15: 0000000000001000 > [60519.821028] irq event stamp: 20385 > [60519.825139] hardirqs last enabled at (20395): [<ffffffff883481e0>] __up_console_sem+0x60/0x70 > [60519.834455] hardirqs last disabled at (20404): [<ffffffff883481c5>] __up_console_sem+0x45/0x70 > [60519.843763] softirqs last enabled at (20372): [<ffffffff881e6a7c>] __irq_exit_rcu+0x19c/0x200 > [60519.853079] softirqs last disabled at (20367): [<ffffffff881e6a7c>] __irq_exit_rcu+0x19c/0x200 > [60519.862389] ---[ end trace be9623465002e439 ]--- This one should fix it: https://git.kernel.dk/cgit/linux-block/commit/?h=for-5.16/block&id=ff1552232b3612edff43a95746a4e78e231ef3d4
Hi, On Tue, Oct 19, 2021 at 06:08:34AM -0600, Jens Axboe wrote: > If we have just one queue type in the plug list, then we can extend our > direct issue to cover a full plug list as well. > > Signed-off-by: Jens Axboe <axboe@kernel.dk> > Reviewed-by: Christoph Hellwig <hch@lst.de> This patch results in a number of warning tracebacks in linux-next. Reverting it fixes the problem. Example tracebacks and bisect result attached. Guenter --- boot from mmc, ext2: [ 10.868421] ------------[ cut here ]------------ [ 10.868795] WARNING: CPU: 0 PID: 1 at kernel/sched/core.c:9477 __might_sleep+0x70/0x98 [ 10.869013] do not call blocking ops when !TASK_RUNNING; state=2 set at [<(ptrval)>] prepare_to_wait+0x6c/0xb0 [ 10.869350] CPU: 0 PID: 1 Comm: swapper Not tainted 5.15.0-rc7-next-20211026-sx1 #1 [ 10.869547] Hardware name: OMAP310 based Siemens SX1 [ 10.869779] [<c000dc00>] (unwind_backtrace) from [<c000cc54>] (show_stack+0x10/0x18) [ 10.870010] [<c000cc54>] (show_stack) from [<c0430830>] (dump_stack+0x20/0x2c) [ 10.870197] [<c0430830>] (dump_stack) from [<c0018bf8>] (__warn+0xac/0xec) [ 10.870372] [<c0018bf8>] (__warn) from [<c0424218>] (warn_slowpath_fmt+0x68/0x80) [ 10.870556] [<c0424218>] (warn_slowpath_fmt) from [<c003ba2c>] (__might_sleep+0x70/0x98) [ 10.870751] [<c003ba2c>] (__might_sleep) from [<c03f4fb4>] (__mmc_claim_host+0x54/0x1d0) [ 10.870947] [<c03f4fb4>] (__mmc_claim_host) from [<c04053c8>] (mmc_mq_queue_rq+0x12c/0x214) [ 10.871148] [<c04053c8>] (mmc_mq_queue_rq) from [<c02b35c8>] (__blk_mq_try_issue_directly+0xe8/0x134) [ 10.871368] [<c02b35c8>] (__blk_mq_try_issue_directly) from [<c02b45c0>] (blk_mq_request_issue_directly+0x30/0x50) [ 10.871609] [<c02b45c0>] (blk_mq_request_issue_directly) from [<c02b4750>] (blk_mq_flush_plug_list+0x170/0x1f4) [ 10.871842] [<c02b4750>] (blk_mq_flush_plug_list) from [<c02a9ee8>] (blk_flush_plug+0x50/0xec) [ 10.872047] [<c02a9ee8>] (blk_flush_plug) from [<c003b410>] (io_schedule_prepare+0x40/0x50) [ 10.872244] [<c003b410>] (io_schedule_prepare) from [<c04324d8>] (io_schedule+0xc/0x24) [ 10.872436] [<c04324d8>] (io_schedule) from [<c0432814>] (bit_wait_io+0xc/0x34) [ 10.872616] [<c0432814>] (bit_wait_io) from [<c0432548>] (__wait_on_bit+0x58/0x98) [ 10.872801] [<c0432548>] (__wait_on_bit) from [<c04325fc>] (out_of_line_wait_on_bit+0x74/0x84) [ 10.873004] [<c04325fc>] (out_of_line_wait_on_bit) from [<c010dfdc>] (__wait_on_buffer+0x34/0x44) [ 10.873215] [<c010dfdc>] (__wait_on_buffer) from [<c018b688>] (wait_on_buffer+0x24/0x34) [ 10.873411] [<c018b688>] (wait_on_buffer) from [<c018d6d4>] (ext4_read_bh+0x58/0x68) [ 10.873598] [<c018d6d4>] (ext4_read_bh) from [<c015aad0>] (ext4_get_branch+0x9c/0x124) [ 10.873789] [<c015aad0>] (ext4_get_branch) from [<c015ada8>] (ext4_ind_map_blocks+0x158/0xa0c) [ 10.873991] [<c015ada8>] (ext4_ind_map_blocks) from [<c0161f74>] (ext4_map_blocks+0x320/0x558) [ 10.874197] [<c0161f74>] (ext4_map_blocks) from [<c017ec78>] (ext4_mpage_readpages+0x31c/0x6a8) [ 10.874403] [<c017ec78>] (ext4_mpage_readpages) from [<c0160044>] (ext4_readahead+0x24/0x2c) [ 10.874602] [<c0160044>] (ext4_readahead) from [<c009ba18>] (read_pages+0x48/0x118) [ 10.874793] [<c009ba18>] (read_pages) from [<c009bda0>] (page_cache_ra_unbounded+0xfc/0x1e8) [ 10.874994] [<c009bda0>] (page_cache_ra_unbounded) from [<c0094a3c>] (filemap_read+0x19c/0x81c) [ 10.875202] [<c0094a3c>] (filemap_read) from [<c0154524>] (ext4_file_read_iter+0x9c/0xf4) [ 10.875400] [<c0154524>] (ext4_file_read_iter) from [<c00da450>] (__kernel_read+0xc4/0x14c) [ 10.875604] [<c00da450>] (__kernel_read) from [<c00e066c>] (bprm_execve+0x204/0x4bc) [ 10.875795] [<c00e066c>] (bprm_execve) from [<c00e1370>] (kernel_execve+0xe4/0x114) [ 10.875982] [<c00e1370>] (kernel_execve) from [<c0423a6c>] (run_init_process+0x60/0x98) [ 10.876175] [<c0423a6c>] (run_init_process) from [<c0423ab0>] (try_to_run_init_process+0xc/0x3c) [ 10.876383] [<c0423ab0>] (try_to_run_init_process) from [<c04314f0>] (kernel_init+0x90/0x108) [ 10.876585] [<c04314f0>] (kernel_init) from [<c00084d0>] (ret_from_fork+0x14/0x24) [ 10.876797] Exception stack(0xc103bfb0 to 0xc103bff8) [ 10.877217] bfa0: 00000000 00000000 00000000 00000000 [ 10.877439] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 10.877634] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 10.877830] irq event stamp: 65423 [ 10.877943] hardirqs last enabled at (65431): [<c004ea98>] __up_console_sem+0x38/0x58 [ 10.878178] hardirqs last disabled at (65438): [<c004ea80>] __up_console_sem+0x20/0x58 [ 10.878372] softirqs last enabled at (65008): [<c0009734>] __do_softirq+0x32c/0x404 [ 10.878579] softirqs last disabled at (64993): [<c001cb00>] irq_exit+0x120/0x15c [ 10.878788] ---[ end trace 3925c0327f8d873a ]--- --- boot from flash, squashfs: [ 10.742470] ------------[ cut here ]------------ [ 10.742812] WARNING: CPU: 0 PID: 1 at kernel/sched/core.c:9477 __might_sleep+0x70/0x98 [ 10.743021] do not call blocking ops when !TASK_RUNNING; state=2 set at [<(ptrval)>] __wait_for_common+0xa4/0x158 [ 10.743365] CPU: 0 PID: 1 Comm: swapper Not tainted 5.15.0-rc7-next-20211026-sx1 #1 [ 10.743593] Hardware name: OMAP310 based Siemens SX1 [ 10.743815] [<c000dc00>] (unwind_backtrace) from [<c000cc54>] (show_stack+0x10/0x18) [ 10.744036] [<c000cc54>] (show_stack) from [<c0430830>] (dump_stack+0x20/0x2c) [ 10.744215] [<c0430830>] (dump_stack) from [<c0018bf8>] (__warn+0xac/0xec) [ 10.744383] [<c0018bf8>] (__warn) from [<c0424218>] (warn_slowpath_fmt+0x68/0x80) [ 10.744709] [<c0424218>] (warn_slowpath_fmt) from [<c003ba2c>] (__might_sleep+0x70/0x98) [ 10.744922] [<c003ba2c>] (__might_sleep) from [<c0433654>] (__mutex_lock+0x24/0x264) [ 10.745106] [<c0433654>] (__mutex_lock) from [<c0433968>] (mutex_lock_nested+0x18/0x24) [ 10.745306] [<c0433968>] (mutex_lock_nested) from [<c03e46f0>] (mtd_queue_rq+0xcc/0x3f0) [ 10.745497] [<c03e46f0>] (mtd_queue_rq) from [<c02b35c8>] (__blk_mq_try_issue_directly+0xe8/0x134) [ 10.745702] [<c02b35c8>] (__blk_mq_try_issue_directly) from [<c02b45c0>] (blk_mq_request_issue_directly+0x30/0x50) [ 10.745928] [<c02b45c0>] (blk_mq_request_issue_directly) from [<c02b4750>] (blk_mq_flush_plug_list+0x170/0x1f4) [ 10.746148] [<c02b4750>] (blk_mq_flush_plug_list) from [<c02a9ee8>] (blk_flush_plug+0x50/0xec) [ 10.746345] [<c02a9ee8>] (blk_flush_plug) from [<c003b410>] (io_schedule_prepare+0x40/0x50) [ 10.746535] [<c003b410>] (io_schedule_prepare) from [<c04324a4>] (io_schedule_timeout+0x10/0x38) [ 10.746732] [<c04324a4>] (io_schedule_timeout) from [<c04329cc>] (__wait_for_common+0xd8/0x158) [ 10.746928] [<c04329cc>] (__wait_for_common) from [<c02a5068>] (submit_bio_wait+0x4c/0x6c) [ 10.747119] [<c02a5068>] (submit_bio_wait) from [<c01b22f4>] (squashfs_bio_read+0x154/0x20c) [ 10.747314] [<c01b22f4>] (squashfs_bio_read) from [<c01b2688>] (squashfs_read_data+0x2dc/0x3d8) [ 10.747510] [<c01b2688>] (squashfs_read_data) from [<c01b2a3c>] (squashfs_cache_get+0x23c/0x2e8) [ 10.747707] [<c01b2a3c>] (squashfs_cache_get) from [<c01b5ba4>] (squashfs_readpage_block+0x28/0x80) [ 10.747909] [<c01b5ba4>] (squashfs_readpage_block) from [<c01b3f74>] (squashfs_readpage+0x580/0x5f4) [ 10.748112] [<c01b3f74>] (squashfs_readpage) from [<c009baa4>] (read_pages+0xd4/0x118) [ 10.748297] [<c009baa4>] (read_pages) from [<c009bda0>] (page_cache_ra_unbounded+0xfc/0x1e8) [ 10.748490] [<c009bda0>] (page_cache_ra_unbounded) from [<c0094a3c>] (filemap_read+0x19c/0x81c) [ 10.748688] [<c0094a3c>] (filemap_read) from [<c00da450>] (__kernel_read+0xc4/0x14c) [ 10.748870] [<c00da450>] (__kernel_read) from [<c00e066c>] (bprm_execve+0x204/0x4bc) [ 10.749051] [<c00e066c>] (bprm_execve) from [<c00e1370>] (kernel_execve+0xe4/0x114) [ 10.749232] [<c00e1370>] (kernel_execve) from [<c0423a6c>] (run_init_process+0x60/0x98) [ 10.749417] [<c0423a6c>] (run_init_process) from [<c0423ab0>] (try_to_run_init_process+0xc/0x3c) [ 10.749615] [<c0423ab0>] (try_to_run_init_process) from [<c04314f0>] (kernel_init+0x90/0x108) [ 10.749808] [<c04314f0>] (kernel_init) from [<c00084d0>] (ret_from_fork+0x14/0x24) [ 10.750013] Exception stack(0xc103bfb0 to 0xc103bff8) [ 10.750280] bfa0: 00000000 00000000 00000000 00000000 [ 10.750482] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 10.750667] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 10.750851] irq event stamp: 67803 [ 10.750958] hardirqs last enabled at (67811): [<c004ea98>] __up_console_sem+0x38/0x58 [ 10.751179] hardirqs last disabled at (67818): [<c004ea80>] __up_console_sem+0x20/0x58 [ 10.751364] softirqs last enabled at (67552): [<c0009734>] __do_softirq+0x32c/0x404 [ 10.751559] softirqs last disabled at (67547): [<c001cb00>] irq_exit+0x120/0x15c [ 10.751753] ---[ end trace e6cf94fcaae1cea0 ]--- --- boot from flash, ext2: [ 12.328280] WARNING: CPU: 0 PID: 1 at kernel/sched/core.c:9477 __might_sleep+0x98/0xac [ 12.328504] do not call blocking ops when !TASK_RUNNING; state=2 set at [<80154954>] prepare_to_wait+0x4c/0x12c [ 12.328787] CPU: 0 PID: 1 Comm: swapper Not tainted 5.15.0-rc7-next-20211026 #1 [ 12.328942] Hardware name: Generic DT based system [ 12.329134] Backtrace: [ 12.329337] [<80b7d33c>] (dump_backtrace) from [<80b7d710>] (show_stack+0x20/0x24) [ 12.329609] r7:00002505 r6:00000009 r5:8014c45c r4:80e397cc [ 12.329752] [<80b7d6f0>] (show_stack) from [<80b9705c>] (dump_stack+0x28/0x30) [ 12.329895] [<80b97034>] (dump_stack) from [<80115040>] (__warn+0xe4/0x164) [ 12.330035] r5:8014c45c r4:80de4198 [ 12.330120] [<80114f5c>] (__warn) from [<80b7dda0>] (warn_slowpath_fmt+0xa0/0xe4) [ 12.330264] r7:8014c45c r6:00002505 r5:80de4198 r4:80de444c [ 12.330371] [<80b7dd04>] (warn_slowpath_fmt) from [<8014c45c>] (__might_sleep+0x98/0xac) [ 12.330523] r8:00000001 r7:8287827c r6:00000001 r5:00000248 r4:80de4914 [ 12.330641] [<8014c3c4>] (__might_sleep) from [<80b9d28c>] (__mutex_lock+0x48/0x6f4) [ 12.330792] r6:00000000 r5:00000000 r4:82878210 [ 12.330889] [<80b9d244>] (__mutex_lock) from [<80b9da60>] (mutex_lock_nested+0x2c/0x34) [ 12.331049] r10:82878200 r9:82382920 r8:00000001 r7:8287827c r6:82878210 r5:828a5038 [ 12.331185] r4:828a5000 [ 12.331259] [<80b9da34>] (mutex_lock_nested) from [<807ca3dc>] (mtd_queue_rq+0x1b4/0x560) [ 12.331411] [<807ca228>] (mtd_queue_rq) from [<805e04d4>] (__blk_mq_try_issue_directly+0x178/0x1c4) [ 12.331577] r10:8197fbbc r9:82382920 r8:00000001 r7:00000001 r6:8287ce00 r5:00000000 [ 12.331708] r4:828a5000 [ 12.331781] [<805e035c>] (__blk_mq_try_issue_directly) from [<805e240c>] (blk_mq_flush_plug_list+0x338/0x5c0) [ 12.331957] r9:8197e000 r8:8197f77c r7:8287ce00 r6:8197fbac r5:00000001 r4:828a5000 [ 12.332087] [<805e20d4>] (blk_mq_flush_plug_list) from [<805d42a8>] (blk_flush_plug+0xf8/0x144) [ 12.332249] r10:8197fbbc r9:8197fbac r8:80b9ba20 r7:8197f860 r6:00000001 r5:8197f854 [ 12.332379] r4:00000000 [ 12.332452] [<805d41b0>] (blk_flush_plug) from [<80b9b584>] (io_schedule+0x50/0x78) [ 12.332602] r10:00000008 r9:00000002 r8:80b9ba20 r7:8197f860 r6:81004254 r5:8197f854 [ 12.332731] r4:00000000 [ 12.332805] [<80b9b534>] (io_schedule) from [<80b9ba3c>] (bit_wait_io+0x1c/0x80) [ 12.332946] r5:8197f854 r4:00000002 [ 12.333031] [<80b9ba20>] (bit_wait_io) from [<80b9b60c>] (__wait_on_bit+0x60/0xac) [ 12.333172] r5:8197f854 r4:8197e000 [ 12.333256] [<80b9b5ac>] (__wait_on_bit) from [<80b9b6f8>] (out_of_line_wait_on_bit+0xa0/0xd4) [ 12.333414] r9:8277d3b0 r8:801550cc r7:61c88647 r6:8197f86c r5:81002020 r4:8197e000 [ 12.333542] [<80b9b658>] (out_of_line_wait_on_bit) from [<8031b554>] (__wait_on_buffer+0x44/0x50) [ 12.333705] r8:82bbd000 r7:40000113 r6:60000113 r5:00000000 r4:827808c8 [ 12.333823] [<8031b510>] (__wait_on_buffer) from [<803ed810>] (ext4_read_bh+0x13c/0x190) [ 12.333975] r5:00000000 r4:827808c8 [ 12.334061] [<803ed6d4>] (ext4_read_bh) from [<803a0f00>] (ext4_get_branch+0xcc/0x168) [ 12.334211] r7:8197f9b0 r6:00000001 r5:827808c8 r4:8197f9e4 [ 12.334318] [<803a0e34>] (ext4_get_branch) from [<803a12d4>] (ext4_ind_map_blocks+0x1e4/0xd1c) [ 12.334477] r10:00000000 r9:00000000 r8:00000004 r7:00000000 r6:8277d3b0 r5:0000000c [ 12.334608] r4:00000000 [ 12.334681] [<803a10f0>] (ext4_ind_map_blocks) from [<803a9d8c>] (ext4_map_blocks+0x114/0x668) [ 12.334849] r10:8277d360 r9:00000000 r8:00000004 r7:00000000 r6:8277d3b0 r5:0000000c [ 12.334980] r4:8197fb08 [ 12.335053] [<803a9c78>] (ext4_map_blocks) from [<803d39bc>] (ext4_mpage_readpages+0x564/0x858) [ 12.335215] r10:00000004 r9:00000000 r8:00000004 r7:00000004 r6:00000000 r5:0000000c [ 12.335345] r4:00000000 [ 12.335419] [<803d3458>] (ext4_mpage_readpages) from [<803a7bd0>] (ext4_readahead+0x44/0x48) [ 12.335579] r10:8772af00 r9:01112cca r8:803a7b8c r7:80c18298 r6:00000000 r5:8197fc14 [ 12.335710] r4:8197fcd4 [ 12.335784] [<803a7b8c>] (ext4_readahead) from [<80274b68>] (read_pages+0x94/0x27c) [ 12.335927] [<80274ad4>] (read_pages) from [<8027512c>] (page_cache_ra_unbounded+0x204/0x2a0) [ 12.336083] r10:8772af00 r9:01112cca r8:8277d4f8 r7:8197fcd4 r6:00000003 r5:00000004 [ 12.336213] r4:8772af00 [ 12.336287] [<80274f28>] (page_cache_ra_unbounded) from [<802754a0>] (ondemand_readahead+0x2d8/0x380) [ 12.336450] r10:00000000 r9:00000000 r8:00000020 r7:00000000 r6:00000003 r5:82eb00f8 [ 12.336580] r4:8197fcd4 [ 12.336654] [<802751c8>] (ondemand_readahead) from [<8027573c>] (page_cache_sync_ra+0x6c/0x70) [ 12.336811] r10:00000000 r9:8197fe60 r8:00000000 r7:00000001 r6:8277d4f8 r5:8197fd54 [ 12.336941] r4:8197fe60 [ 12.337014] [<802756d0>] (page_cache_sync_ra) from [<80267e04>] (filemap_get_pages+0x114/0x818) [ 12.337167] [<80267cf0>] (filemap_get_pages) from [<8026aad8>] (filemap_read+0xf0/0x3f0) [ 12.337319] r10:8197fe48 r9:8197fe60 r8:00000000 r7:82eb0020 r6:8197fe48 r5:00000000 [ 12.337450] r4:8277d3b0 [ 12.337523] [<8026a9e8>] (filemap_read) from [<8026aee0>] (generic_file_read_iter+0x108/0x164) [ 12.337680] r10:82bb385c r9:00000000 r8:00000000 r7:00000100 r6:8197fe48 r5:00000000 [ 12.337998] r4:8197fe60 [ 12.338092] [<8026add8>] (generic_file_read_iter) from [<80399048>] (ext4_file_read_iter+0x5c/0x140) [ 12.338266] r10:82bb385c r9:00000000 r8:00000000 r7:8197fef8 r6:8277d3b0 r5:8197fe60 [ 12.338396] r4:8197fe48 [ 12.338470] [<80398fec>] (ext4_file_read_iter) from [<802ce8a8>] (__kernel_read+0x130/0x2e0) [ 12.338626] r7:8197fef8 r6:00000100 r5:00000000 r4:82eb0020 [ 12.338731] [<802ce778>] (__kernel_read) from [<802ceaa0>] (kernel_read+0x48/0x8c) [ 12.338884] r9:00000000 r8:8100ca3c r7:819e21e0 r6:8106cc08 r5:8106cbe8 r4:82bb3800 [ 12.339012] [<802cea58>] (kernel_read) from [<802d7cd0>] (bprm_execve+0x2a4/0x61c) [ 12.339156] r5:8106cbe8 r4:82bb3800 [ 12.339240] [<802d7a2c>] (bprm_execve) from [<802d8f70>] (kernel_execve+0x120/0x180) [ 12.339387] r10:00000000 r9:00000000 r8:8100ca3c r7:8100c9b0 r6:819e21e0 r5:82bb3800 [ 12.339516] r4:00000000 [ 12.339589] [<802d8e50>] (kernel_execve) from [<80b7d0e4>] (run_init_process+0xb4/0xe0) [ 12.339742] r9:00000000 r8:00000000 r7:80eb1744 r6:810dc540 r5:8100ca48 r4:80dde074 [ 12.339871] [<80b7d030>] (run_init_process) from [<80b7d12c>] (try_to_run_init_process+0x1c/0x48) [ 12.340028] r7:00000000 r6:00000000 r5:80dde074 r4:810ff000 [ 12.340135] [<80b7d110>] (try_to_run_init_process) from [<80b97f20>] (kernel_init+0xcc/0x140) [ 12.340287] r5:8100c9b0 r4:810ff000 [ 12.340371] [<80b97e54>] (kernel_init) from [<801000f8>] (ret_from_fork+0x14/0x3c) [ 12.340555] Exception stack(0x8197ffb0 to 0x8197fff8) [ 12.340720] ffa0: 00000000 00000000 00000000 00000000 [ 12.340873] ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 12.341015] ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 12.341154] r5:80b97e54 r4:00000000 [ 12.341297] irq event stamp: 338305 [ 12.341394] hardirqs last enabled at (338313): [<8016b190>] __up_console_sem+0x70/0x90 [ 12.341546] hardirqs last disabled at (338320): [<8016b17c>] __up_console_sem+0x5c/0x90 [ 12.341693] softirqs last enabled at (337228): [<801015ac>] __do_softirq+0x3a4/0x4bc [ 12.341849] softirqs last disabled at (337219): [<8011abf8>] __irq_exit_rcu+0x154/0x198 [ 12.342017] ---[ end trace 90c4b572201178ca ]--- --- bisect: # bad: [2376e5fe91bcad74b997d2cc0535abff79ec73c5] Add linux-next specific files for 20211026 # good: [3906fe9bb7f1a2c8667ae54e967dc8690824f4ea] Linux 5.15-rc7 git bisect start 'HEAD' 'v5.15-rc7' # good: [18298270669947b661fe47bf7ec755a6d254c464] Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git git bisect good 18298270669947b661fe47bf7ec755a6d254c464 # bad: [2701cbf5818d2e249bc890297b6ccb4665bee93d] Merge branch 'auto-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git git bisect bad 2701cbf5818d2e249bc890297b6ccb4665bee93d # good: [3462546aa74a9901a8955c3b2c3e55d736353360] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git git bisect good 3462546aa74a9901a8955c3b2c3e55d736353360 # bad: [0cb3815f5831d5d81e742a6ec9b8c5a8a24e3a3b] Merge branch 'for-next' of git://git.kernel.dk/linux-block.git git bisect bad 0cb3815f5831d5d81e742a6ec9b8c5a8a24e3a3b # bad: [36413f42eaf5ccaa42f9a79756129abc34cd27c9] Merge branch 'for-5.16/drivers' into for-next git bisect bad 36413f42eaf5ccaa42f9a79756129abc34cd27c9 # good: [d28e4dff085c5a87025c9a0a85fb798bd8e9ca17] block: ataflop: more blk-mq refactoring fixes git bisect good d28e4dff085c5a87025c9a0a85fb798bd8e9ca17 # good: [88eb469d0dcbd2206f8f16e76a2ab7a32475fbed] Merge branch 'for-5.16/bdev-size' into for-next git bisect good 88eb469d0dcbd2206f8f16e76a2ab7a32475fbed # bad: [49389040df8f2ac0e03412d6dcad0ef322cbbc1b] Merge branch 'for-5.16/block' into for-next git bisect bad 49389040df8f2ac0e03412d6dcad0ef322cbbc1b # bad: [ce807b324fd4e02ecd8d5e49fab16baad4af9575] Merge branch 'for-5.16/io_uring' into for-next git bisect bad ce807b324fd4e02ecd8d5e49fab16baad4af9575 # good: [06114f3294e91818408c0008446ccf41d67cd63e] Merge branch 'for-5.16/bdev-size' into for-next git bisect good 06114f3294e91818408c0008446ccf41d67cd63e # bad: [44b2b16cb77838b9596e6551088b1b18657398c2] Merge branch 'for-5.16/block' into for-next git bisect bad 44b2b16cb77838b9596e6551088b1b18657398c2 # bad: [59d62b58f1203a6b59a3e51244dee91ea80340cd] Merge branch 'for-5.16/block' into for-next git bisect bad 59d62b58f1203a6b59a3e51244dee91ea80340cd # bad: [dc5fc361d891e089dfd9c0a975dc78041036b906] block: attempt direct issue of plug list git bisect bad dc5fc361d891e089dfd9c0a975dc78041036b906 # good: [bc490f81731e181b07b8d7577425c06ae91692c8] block: change plugging to use a singly linked list git bisect good bc490f81731e181b07b8d7577425c06ae91692c8 # first bad commit: [dc5fc361d891e089dfd9c0a975dc78041036b906] block: attempt direct issue of plug list
On Oct 26, 2021 / 08:42, Jens Axboe wrote: > On 10/25/21 11:20 PM, Shinichiro Kawasaki wrote: > > On Oct 19, 2021 / 06:08, Jens Axboe wrote: > >> If we have just one queue type in the plug list, then we can extend our > >> direct issue to cover a full plug list as well. > >> > >> Signed-off-by: Jens Axboe <axboe@kernel.dk> > > > > Hi Jens, I tried out for-next branch and observed A WARNING "do not call > > blocking ops when !TASK_RUNNING" [1]. Reverting this patch from the for-next > > branch, the warning disappears. The warning was triggered when mkfs.xfs is > > run for memory backed null_blk devices with "none" scheduler. (snip) > > This one should fix it: > > https://git.kernel.dk/cgit/linux-block/commit/?h=for-5.16/block&id=ff1552232b3612edff43a95746a4e78e231ef3d4 I confirmed that the patch fixes the warning. Good. Thank you Ming, Jens.
On 10/26/21 7:13 PM, Guenter Roeck wrote: > Hi, > > On Tue, Oct 19, 2021 at 06:08:34AM -0600, Jens Axboe wrote: >> If we have just one queue type in the plug list, then we can extend our >> direct issue to cover a full plug list as well. >> >> Signed-off-by: Jens Axboe <axboe@kernel.dk> >> Reviewed-by: Christoph Hellwig <hch@lst.de> > > This patch results in a number of warning tracebacks in linux-next. > Reverting it fixes the problem. Example tracebacks and bisect result > attached. See other replies in this thread, it's fixed in the curren tree.
diff --git a/block/blk-core.c b/block/blk-core.c index 14d20909f61a..e6ad5b51d0c3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1555,6 +1555,7 @@ void blk_start_plug_nr_ios(struct blk_plug *plug, unsigned short nr_ios) plug->nr_ios = min_t(unsigned short, nr_ios, BLK_MAX_REQUEST_COUNT); plug->rq_count = 0; plug->multiple_queues = false; + plug->has_elevator = false; plug->nowait = false; INIT_LIST_HEAD(&plug->cb_list); diff --git a/block/blk-mq.c b/block/blk-mq.c index 620233b85af2..d0fe86b46d1b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2147,6 +2147,58 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, spin_unlock(&ctx->lock); } +static void blk_mq_commit_rqs(struct blk_mq_hw_ctx *hctx, int *queued, + bool from_schedule) +{ + if (hctx->queue->mq_ops->commit_rqs) { + trace_block_unplug(hctx->queue, *queued, !from_schedule); + hctx->queue->mq_ops->commit_rqs(hctx); + } + *queued = 0; +} + +static void blk_mq_plug_issue_direct(struct blk_plug *plug, bool from_schedule) +{ + struct blk_mq_hw_ctx *hctx = NULL; + struct request *rq; + int queued = 0; + int errors = 0; + + while ((rq = rq_list_pop(&plug->mq_list))) { + bool last = rq_list_empty(plug->mq_list); + blk_status_t ret; + + if (hctx != rq->mq_hctx) { + if (hctx) + blk_mq_commit_rqs(hctx, &queued, from_schedule); + hctx = rq->mq_hctx; + } + + ret = blk_mq_request_issue_directly(rq, last); + switch (ret) { + case BLK_STS_OK: + queued++; + break; + case BLK_STS_RESOURCE: + case BLK_STS_DEV_RESOURCE: + blk_mq_request_bypass_insert(rq, false, last); + blk_mq_commit_rqs(hctx, &queued, from_schedule); + return; + default: + blk_mq_end_request(rq, ret); + errors++; + break; + } + } + + /* + * If we didn't flush the entire list, we could have told the driver + * there was more coming, but that turned out to be a lie. + */ + if (errors) + blk_mq_commit_rqs(hctx, &queued, from_schedule); +} + void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) { struct blk_mq_hw_ctx *this_hctx; @@ -2158,6 +2210,12 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) return; plug->rq_count = 0; + if (!plug->multiple_queues && !plug->has_elevator) { + blk_mq_plug_issue_direct(plug, from_schedule); + if (rq_list_empty(plug->mq_list)) + return; + } + this_hctx = NULL; this_ctx = NULL; depth = 0; @@ -2374,6 +2432,8 @@ static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq) if (nxt && nxt->q != rq->q) plug->multiple_queues = true; } + if (!plug->has_elevator && (rq->rq_flags & RQF_ELV)) + plug->has_elevator = true; rq->rq_next = NULL; rq_list_add(&plug->mq_list, rq); plug->rq_count++; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 80668e316eea..2e93682f8f68 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -720,6 +720,7 @@ struct blk_plug { unsigned short rq_count; bool multiple_queues; + bool has_elevator; bool nowait; struct list_head cb_list; /* md requires an unplug callback */
If we have just one queue type in the plug list, then we can extend our direct issue to cover a full plug list as well. Signed-off-by: Jens Axboe <axboe@kernel.dk> --- block/blk-core.c | 1 + block/blk-mq.c | 60 ++++++++++++++++++++++++++++++++++++++++++ include/linux/blkdev.h | 1 + 3 files changed, 62 insertions(+)