why there isn't some documentation #1

cppdev-123 · 2019-09-13T16:35:42Z

why the man pages doesn't contain any documentation about this library
and is this faster than epoll and if yes then by any factor ?

axboe · 2019-09-13T16:43:12Z

Because no one has written them yet? Do you want to help write them?

You might want to look into how you communicate, you come across as very demanding. You know how open source works - by people spending their time working on something they want to work on? They don't owe you anything, in fact you should be thankful for them donating their time and resources.

epoll vs io_uring, someone did this last week: https://twitter.com/CondyChen/status/1170567616525557760

cppdev-123 · 2019-09-14T07:32:07Z

I mean is this already exists in linux or I have to do somethings to make it work
I use the man pages to explore the linux api and while searching for equivalent to iocp on windows I came to this
sorry I am not so expert in linux , I was a windows only programmer but I'm going to program for linux because server is running linux

codebrainz · 2020-02-13T22:30:45Z

Tone of the OP aside, this probably shouldn't be closed since it's totally valid.

Add kworker-hang test to reproduce this: [11133.980033] INFO: task kworker/u8:3:16315 blocked for more than 10 seconds. [11133.980041] Tainted: G OE 5.15.0-rc4-for-5.16-io-uring-00060-g4922ab639eb6 axboe#4 [11133.980047] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [11133.980052] task:kworker/u8:3 state:D stack: 0 pid:16315 ppid: 2 flags:0x00004000 [11133.980061] Workqueue: events_unbound io_ring_exit_work [11133.980068] Call Trace: [11133.980076] __schedule+0x453/0x1850 [11133.980097] ? usleep_range+0x90/0x90 [11133.980104] schedule+0x59/0xc0 [11133.980111] schedule_timeout+0x1aa/0x1f0 [11133.980119] ? mark_held_locks+0x49/0x70 [11133.980128] ? lockdep_hardirqs_on_prepare+0xff/0x180 [11133.980134] ? _raw_spin_unlock_irq+0x24/0x40 [11133.980143] __wait_for_common+0xc2/0x170 [11133.980158] io_ring_exit_work+0x42c/0x44a [11133.980166] ? io_uring_del_tctx_node+0xad/0xad [11133.980178] ? verify_cpu+0xf0/0x100 [11133.980193] process_one_work+0x23b/0x550 [11133.980209] worker_thread+0x55/0x3c0 [11133.980214] ? process_one_work+0x550/0x550 [11133.980223] kthread+0x140/0x160 [11133.980229] ? set_kthread_struct+0x40/0x40 [11133.980237] ret_from_fork+0x1f/0x30 [11133.980278] Showing all locks held in the system: [11133.980282] 2 locks held by kworker/u8:0/8: [11133.980286] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980304] axboe#1: ffffc90000187e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980322] 1 lock held by khungtaskd/39: [11133.980325] #0: ffffffff82977740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x174 [11133.980348] 2 locks held by kworker/u8:9/760: [11133.980351] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980366] axboe#1: ffffc9000176fe70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980385] 1 lock held by in:imklog/926: [11133.980388] #0: ffff88813208c2f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4a/0x60 [11133.980434] 1 lock held by htop/13609: [11133.980438] 2 locks held by kworker/u8:3/16315: [11133.980441] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980456] axboe#1: ffffc90008d43e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [11133.980475] 1 lock held by dmesg/18421: [11133.980478] #0: ffff88824be300d0 (&user->lock){+.+.}-{3:3}, at: devkmsg_read+0x4b/0x230 [11133.980498] ============================================= Link: axboe#448 Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>

This is the reproducer for the kworker hang bug. Reproduction Steps: 1) A user task calls io_uring_queue_exit(). 2) Suspend the task with SIGSTOP / SIGTRAP before the ring exit is finished (do it as soon as step (1) is done). 3) Wait for `/proc/sys/kernel/hung_task_timeout_secs` seconds elapsed. 4) We get a complaint from the khungtaskd because the kworker is stuck in an uninterruptible state (D). The kworkers waiting on ring exit are not progressing as the task cannot proceed. When the user task is continued (e.g. get SIGCONT after SIGSTOP, or continue after SIGTRAP breakpoint), the kworkers then can finish the ring exit. We need a special handling for this case to avoid khungtaskd complaint. Currently we don't have the fix for this. The dmesg says: [247390.432294] INFO: task kworker/u8:2:358488 blocked for more than 10 seconds. [247390.432314] Tainted: G OE 5.15.0-stable #5 [247390.432322] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [247390.432329] task:kworker/u8:2 state:D stack: 0 pid:358488 ppid: 2 flags:0x00004000 [247390.432341] Workqueue: events_unbound io_ring_exit_work [247390.432354] Call Trace: [247390.432368] __schedule+0x453/0x1850 [247390.432388] ? lock_acquire+0xc8/0x2d0 [247390.432404] ? usleep_range+0x90/0x90 [247390.432412] schedule+0x59/0xc0 [247390.432420] schedule_timeout+0x1aa/0x1f0 [247390.432429] ? mark_held_locks+0x49/0x70 [247390.432439] ? lockdep_hardirqs_on_prepare+0xff/0x180 [247390.432445] ? _raw_spin_unlock_irq+0x24/0x40 [247390.432456] __wait_for_common+0xc2/0x170 [247390.432473] io_ring_exit_work+0x1d9/0x750 [247390.432486] ? io_uring_del_tctx_node+0xe0/0xe0 [247390.432502] ? verify_cpu+0xf0/0x100 [247390.432520] process_one_work+0x23b/0x550 [247390.432540] worker_thread+0x55/0x3c0 [247390.432546] ? process_one_work+0x550/0x550 [247390.432556] kthread+0x140/0x160 [247390.432564] ? set_kthread_struct+0x40/0x40 [247390.432574] ret_from_fork+0x1f/0x30 [247390.432605] INFO: task kworker/u8:0:359615 blocked for more than 10 seconds. [247390.432613] Tainted: G OE 5.15.0-stable #5 [247390.432620] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [247390.432626] task:kworker/u8:0 state:D stack: 0 pid:359615 ppid: 2 flags:0x00004000 [247390.432635] Workqueue: events_unbound io_ring_exit_work [247390.432643] Call Trace: [247390.432653] __schedule+0x453/0x1850 [247390.432676] ? usleep_range+0x90/0x90 [247390.432684] schedule+0x59/0xc0 [247390.432691] schedule_timeout+0x1aa/0x1f0 [247390.432700] ? mark_held_locks+0x49/0x70 [247390.432710] ? lockdep_hardirqs_on_prepare+0xff/0x180 [247390.432717] ? _raw_spin_unlock_irq+0x24/0x40 [247390.432728] __wait_for_common+0xc2/0x170 [247390.432744] io_ring_exit_work+0x1d9/0x750 [247390.432758] ? io_uring_del_tctx_node+0xe0/0xe0 [247390.432772] ? verify_cpu+0xf0/0x100 [247390.432788] process_one_work+0x23b/0x550 [247390.432807] worker_thread+0x55/0x3c0 [247390.432813] ? process_one_work+0x550/0x550 [247390.432824] kthread+0x140/0x160 [247390.432830] ? set_kthread_struct+0x40/0x40 [247390.432839] ret_from_fork+0x1f/0x30 [247390.432870] Showing all locks held in the system: [247390.432877] 1 lock held by khungtaskd/40: [247390.432880] #0: ffffffff82976700 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x174 [247390.432911] 1 lock held by in:imklog/922: [247390.432915] #0: ffff8881041cfcf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4a/0x60 [247390.432977] 2 locks held by pager/318088: [247390.432981] #0: ffff8881208d4898 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x50 [247390.433001] #1: ffffc900010fd2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x49e/0x660 [247390.433024] 1 lock held by htop/341462: [247390.433032] 2 locks held by kworker/u8:2/358488: [247390.433035] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433053] #1: ffffc90003797e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433071] 2 locks held by kworker/u8:0/359615: [247390.433075] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433092] #1: ffffc90003597e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433110] 1 lock held by dmesg/361178: [247390.433113] #0: ffff88810b5300d0 (&user->lock){+.+.}-{3:3}, at: devkmsg_read+0x4b/0x230 [247390.433134] ============================================= Cc: Pavel Begunkov <asml.silence@gmail.com> Link: #448 Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id> Signed-off-by: Jens Axboe <axboe@kernel.dk>

This is the reproducer for the kworker hang bug. Reproduction Steps: 1) A user task calls io_uring_queue_exit(). 2) Suspend the task with SIGSTOP / SIGTRAP before the ring exit is finished (do it as soon as step (1) is done). 3) Wait for `/proc/sys/kernel/hung_task_timeout_secs` seconds elapsed. 4) We get a complaint from the khungtaskd because the kworker is stuck in an uninterruptible state (D). The kworkers waiting on ring exit are not progressing as the task cannot proceed. When the user task is continued (e.g. get SIGCONT after SIGSTOP, or continue after SIGTRAP breakpoint), the kworkers then can finish the ring exit. We need a special handling for this case to avoid khungtaskd complaint. Currently we don't have the fix for this. The dmesg says: [247390.432294] INFO: task kworker/u8:2:358488 blocked for more than 10 seconds. [247390.432314] Tainted: G OE 5.15.0-stable axboe#5 [247390.432322] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [247390.432329] task:kworker/u8:2 state:D stack: 0 pid:358488 ppid: 2 flags:0x00004000 [247390.432341] Workqueue: events_unbound io_ring_exit_work [247390.432354] Call Trace: [247390.432368] __schedule+0x453/0x1850 [247390.432388] ? lock_acquire+0xc8/0x2d0 [247390.432404] ? usleep_range+0x90/0x90 [247390.432412] schedule+0x59/0xc0 [247390.432420] schedule_timeout+0x1aa/0x1f0 [247390.432429] ? mark_held_locks+0x49/0x70 [247390.432439] ? lockdep_hardirqs_on_prepare+0xff/0x180 [247390.432445] ? _raw_spin_unlock_irq+0x24/0x40 [247390.432456] __wait_for_common+0xc2/0x170 [247390.432473] io_ring_exit_work+0x1d9/0x750 [247390.432486] ? io_uring_del_tctx_node+0xe0/0xe0 [247390.432502] ? verify_cpu+0xf0/0x100 [247390.432520] process_one_work+0x23b/0x550 [247390.432540] worker_thread+0x55/0x3c0 [247390.432546] ? process_one_work+0x550/0x550 [247390.432556] kthread+0x140/0x160 [247390.432564] ? set_kthread_struct+0x40/0x40 [247390.432574] ret_from_fork+0x1f/0x30 [247390.432605] INFO: task kworker/u8:0:359615 blocked for more than 10 seconds. [247390.432613] Tainted: G OE 5.15.0-stable axboe#5 [247390.432620] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [247390.432626] task:kworker/u8:0 state:D stack: 0 pid:359615 ppid: 2 flags:0x00004000 [247390.432635] Workqueue: events_unbound io_ring_exit_work [247390.432643] Call Trace: [247390.432653] __schedule+0x453/0x1850 [247390.432676] ? usleep_range+0x90/0x90 [247390.432684] schedule+0x59/0xc0 [247390.432691] schedule_timeout+0x1aa/0x1f0 [247390.432700] ? mark_held_locks+0x49/0x70 [247390.432710] ? lockdep_hardirqs_on_prepare+0xff/0x180 [247390.432717] ? _raw_spin_unlock_irq+0x24/0x40 [247390.432728] __wait_for_common+0xc2/0x170 [247390.432744] io_ring_exit_work+0x1d9/0x750 [247390.432758] ? io_uring_del_tctx_node+0xe0/0xe0 [247390.432772] ? verify_cpu+0xf0/0x100 [247390.432788] process_one_work+0x23b/0x550 [247390.432807] worker_thread+0x55/0x3c0 [247390.432813] ? process_one_work+0x550/0x550 [247390.432824] kthread+0x140/0x160 [247390.432830] ? set_kthread_struct+0x40/0x40 [247390.432839] ret_from_fork+0x1f/0x30 [247390.432870] Showing all locks held in the system: [247390.432877] 1 lock held by khungtaskd/40: [247390.432880] #0: ffffffff82976700 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x174 [247390.432911] 1 lock held by in:imklog/922: [247390.432915] #0: ffff8881041cfcf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4a/0x60 [247390.432977] 2 locks held by pager/318088: [247390.432981] #0: ffff8881208d4898 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x50 [247390.433001] axboe#1: ffffc900010fd2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x49e/0x660 [247390.433024] 1 lock held by htop/341462: [247390.433032] 2 locks held by kworker/u8:2/358488: [247390.433035] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433053] axboe#1: ffffc90003797e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433071] 2 locks held by kworker/u8:0/359615: [247390.433075] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433092] axboe#1: ffffc90003597e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [247390.433110] 1 lock held by dmesg/361178: [247390.433113] #0: ffff88810b5300d0 (&user->lock){+.+.}-{3:3}, at: devkmsg_read+0x4b/0x230 [247390.433134] ============================================= Cc: Pavel Begunkov <asml.silence@gmail.com> Link: axboe#448 Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>

Add kworker-hang test to reproduce this: [28335.037622] INFO: task kworker/u8:3:77596 blocked for more than 10 seconds. [28335.037629] Tainted: G W OE 5.15.0-rc4-for-5.16-io-uring-00060-g4922ab639eb6 axboe#4 [28335.037637] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [28335.037642] task:kworker/u8:3 state:D stack: 0 pid:77596 ppid: 2 flags:0x00004000 [28335.037650] Workqueue: events_unbound io_ring_exit_work [28335.037658] Call Trace: [28335.037667] __schedule+0x453/0x1850 [28335.037681] ? lock_acquire+0xc8/0x2d0 [28335.037688] ? io_ring_exit_work+0x98/0x44a [28335.037700] ? usleep_range+0x90/0x90 [28335.037707] schedule+0x59/0xc0 [28335.037715] schedule_timeout+0x1aa/0x1f0 [28335.037723] ? mark_held_locks+0x49/0x70 [28335.037733] ? lockdep_hardirqs_on_prepare+0xff/0x180 [28335.037740] ? _raw_spin_unlock_irq+0x24/0x40 [28335.037750] __wait_for_common+0xc2/0x170 [28335.037767] io_ring_exit_work+0x42c/0x44a [28335.037776] ? io_uring_del_tctx_node+0xad/0xad [28335.037790] ? verify_cpu+0xf0/0x100 [28335.037806] process_one_work+0x23b/0x550 [28335.037824] worker_thread+0x55/0x3c0 [28335.037830] ? process_one_work+0x550/0x550 [28335.037840] kthread+0x140/0x160 [28335.037846] ? set_kthread_struct+0x40/0x40 [28335.037856] ret_from_fork+0x1f/0x30 [28335.037887] INFO: task kworker/u8:4:78057 blocked for more than 10 seconds. [28335.037895] Tainted: G W OE 5.15.0-rc4-for-5.16-io-uring-00060-g4922ab639eb6 axboe#4 [28335.037901] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [28335.037907] task:kworker/u8:4 state:D stack: 0 pid:78057 ppid: 2 flags:0x00004000 [28335.037915] Workqueue: events_unbound io_ring_exit_work [28335.037922] Call Trace: [28335.037931] __schedule+0x453/0x1850 [28335.037946] ? lock_acquire+0xc8/0x2d0 [28335.037953] ? io_ring_exit_work+0x98/0x44a [28335.037965] ? usleep_range+0x90/0x90 [28335.037973] schedule+0x59/0xc0 [28335.037980] schedule_timeout+0x1aa/0x1f0 [28335.037989] ? mark_held_locks+0x49/0x70 [28335.037999] ? lockdep_hardirqs_on_prepare+0xff/0x180 [28335.038005] ? _raw_spin_unlock_irq+0x24/0x40 [28335.038016] __wait_for_common+0xc2/0x170 [28335.038032] io_ring_exit_work+0x42c/0x44a [28335.038041] ? io_uring_del_tctx_node+0xad/0xad [28335.038055] ? verify_cpu+0xf0/0x100 [28335.038070] process_one_work+0x23b/0x550 [28335.038089] worker_thread+0x55/0x3c0 [28335.038095] ? process_one_work+0x550/0x550 [28335.038105] kthread+0x140/0x160 [28335.038111] ? set_kthread_struct+0x40/0x40 [28335.038120] ret_from_fork+0x1f/0x30 [28335.038148] Showing all locks held in the system: [28335.038155] 1 lock held by khungtaskd/39: [28335.038159] #0: ffffffff82977740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x174 [28335.038189] 1 lock held by in:imklog/926: [28335.038193] #0: ffff88813208c2f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4a/0x60 [28335.038253] 2 locks held by kworker/u8:1/68219: [28335.038257] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038274] axboe#1: ffffc90003f7fe70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038291] 2 locks held by kworker/u8:0/76320: [28335.038295] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038311] axboe#1: ffffc90003ca7e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038328] 2 locks held by kworker/u8:2/76681: [28335.038331] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038347] axboe#1: ffffc9000837be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038365] 2 locks held by kworker/u8:3/77596: [28335.038368] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038384] axboe#1: ffffc900083e3e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038401] 1 lock held by dmesg/78014: [28335.038405] #0: ffff888217c180d0 (&user->lock){+.+.}-{3:3}, at: devkmsg_read+0x4b/0x230 [28335.038423] 2 locks held by kworker/u8:4/78057: [28335.038427] #0: ffff888100106938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038443] axboe#1: ffffc900088b7e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x1c1/0x550 [28335.038463] ============================================= [28335.038468] NMI backtrace for cpu 2 [28335.038471] CPU: 2 PID: 39 Comm: khungtaskd Tainted: G W OE 5.15.0-rc4-for-5.16-io-uring-00060-g4922ab639eb6 axboe#4 8b24b2500a34cedea2e69c8d84eb4c855e713e61 [28335.038478] Hardware name: Acer Aspire ES1-421/OLVIA_BE, BIOS V1.05 07/02/2015 [28335.038481] Call Trace: [28335.038486] dump_stack_lvl+0x57/0x72 [28335.038495] nmi_cpu_backtrace.cold+0x32/0x7f [28335.038500] ? lapic_can_unplug_cpu+0x80/0x80 [28335.038510] nmi_trigger_cpumask_backtrace+0xd1/0xe0 [28335.038520] watchdog+0x5b3/0x670 [28335.038528] ? _raw_spin_unlock_irqrestore+0x37/0x40 [28335.038535] ? hungtask_pm_notify+0x40/0x40 [28335.038544] kthread+0x140/0x160 [28335.038549] ? set_kthread_struct+0x40/0x40 [28335.038558] ret_from_fork+0x1f/0x30 [28335.038586] Sending NMI from CPU 2 to CPUs 0-1,3: [28335.038601] NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xb/0x10 [28335.038609] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xb/0x10 [28335.038615] NMI backtrace for cpu 3 [28335.038618] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G W OE 5.15.0-rc4-for-5.16-io-uring-00060-g4922ab639eb6 axboe#4 8b24b2500a34cedea2e69c8d84eb4c855e713e61 [28335.038622] Hardware name: Acer Aspire ES1-421/OLVIA_BE, BIOS V1.05 07/02/2015 [28335.038624] RIP: 0010:acpi_idle_enter+0x92/0x100 [28335.038631] Code: 00 41 bc 01 00 00 00 48 8b 2c 02 0f b6 45 01 3c 03 75 07 0f 09 0f 1f 44 00 00 0f b6 45 08 3c 01 74 3a 3c 02 74 45 8b 55 04 ec <48> 8b 05 07 fd 51 01 a9 00 00 00 80 75 08 48 8b 15 3d 74 9d 02 ed [28335.038634] RSP: 0018:ffffc900001d7e90 EFLAGS: 00000093 [28335.038637] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000040 [28335.038639] RDX: 0000000000000414 RSI: ffff88810135b000 RDI: ffff888103161000 [28335.038641] RBP: ffff88810135b098 R08: ffffffff82ae8f00 R09: 0000000000000018 [28335.038643] R10: 0000000000000170 R11: 0000000000000af8 R12: 0000000000000002 [28335.038644] R13: ffffffff82ae8fe8 R14: 0000000000000002 R15: 0000000000000000 [28335.038646] FS: 0000000000000000(0000) GS:ffff888313d80000(0000) knlGS:0000000000000000 [28335.038649] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [28335.038651] CR2: 00001e5478e1a518 CR3: 0000000199650000 CR4: 00000000000406e0 [28335.038653] Call Trace: [28335.038656] cpuidle_enter_state+0x9b/0x460 [28335.038665] cpuidle_enter+0x29/0x40 [28335.038670] do_idle+0x1fb/0x2a0 [28335.038676] cpu_startup_entry+0x19/0x20 [28335.038680] secondary_startup_64_no_verify+0xc2/0xcb Cc: Pavel Begunkov <asml.silence@gmail.com> Link: axboe#448 Signed-off-by: Ammar Faizi <ammar.faizi@students.amikom.ac.id>

... to avoid valgrind's complaint: ==2254978== Syscall param write(buf) points to uninitialised byte(s) ==2254978== at 0x498EA37: write (write.c:26) ==2254978== by 0x109F17: test_underprep_fail (submit-link-fail.c:82) ==2254978== by 0x109F17: main (submit-link-fail.c:141) ==2254978== Address 0x1ffefffb07 is on thread 1's stack ==2254978== in frame axboe#1, created by main (submit-link-fail.c:123) Link: https://test.com/axboe/liburing/issues/640 Reported-by: Vitaly Chikunov <vt@altlinux.org> Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>

... to avoid valgrind's complaint: ==2254978== Syscall param write(buf) points to uninitialised byte(s) ==2254978== at 0x498EA37: write (write.c:26) ==2254978== by 0x109F17: test_underprep_fail (submit-link-fail.c:82) ==2254978== by 0x109F17: main (submit-link-fail.c:141) ==2254978== Address 0x1ffefffb07 is on thread 1's stack ==2254978== in frame #1, created by main (submit-link-fail.c:123) Link: #640 Reported-by: Vitaly Chikunov <vt@altlinux.org> Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org> Link: https://lore.kernel.org/r/20220810002735.2260172-8-ammar.faizi@intel.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

axboe closed this as completed Sep 13, 2019

axboe mentioned this issue Oct 20, 2019

Support asynchronous-but-blocking socket reads #17

Closed

axboe mentioned this issue Jan 12, 2020

Question about LIBURING_UDATA_TIMEOUT filtering #53

Closed

axboe mentioned this issue Apr 11, 2020

question: liburing access patterns #103

Closed

isilence mentioned this issue Apr 17, 2021

Adding test suite for #310 multishot poll / update, tests basic functionality and some error boundary conditions. #317

Closed

lano1106 mentioned this issue May 16, 2021

unexpected high count of io_worker threads by using the IOSQE_ASYNC flag #349

Closed

lano1106 mentioned this issue Jun 15, 2021

buffer leak when using IOSQE_BUFFER_SELECT #359

Closed

banxianxie mentioned this issue Aug 14, 2021

Unexpected io_uring_submit() return value after io_uring_wait_cqe_timeout()? #411

Closed

beldzhang mentioned this issue Oct 19, 2021

5.15-rc6 vs 5.10: iou-wrk-# spawned too much; iou-sqp-# hang; linked timeout returen -EINVAL #460

Closed

hi-glenn mentioned this issue Aug 3, 2022

[examples/io_uring-udp] queue_init: Invalid argument #637

Closed

lano1106 mentioned this issue Dec 27, 2022

Problem with defered completion and sqpoll thread (v6.1.1) #758

Closed

ll123456 mentioned this issue Mar 27, 2024

fio3.36 hit out of memory when add 'verify' parameter #1108

Closed

rowe0x mentioned this issue Aug 13, 2024

Long tail between submit event to complete event exceed 1 second #1203

Closed

vt-alt mentioned this issue Oct 31, 2024

ppc64le: Tests failed (2): <no-mmap-inval.t> <reg-fd-only.t> #1207

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

why there isn't some documentation #1

why there isn't some documentation #1

cppdev-123 commented Sep 13, 2019

axboe commented Sep 13, 2019

cppdev-123 commented Sep 14, 2019

codebrainz commented Feb 13, 2020

why there isn't some documentation #1

why there isn't some documentation #1

Comments

cppdev-123 commented Sep 13, 2019

axboe commented Sep 13, 2019

cppdev-123 commented Sep 14, 2019

codebrainz commented Feb 13, 2020