The patch titled libata-core: convert to use cancel_rearming_delayed_work() has been added to the -mm tree. Its filename is libata-core-convert-to-use-cancel_rearming_delayed_work.patch *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: libata-core: convert to use cancel_rearming_delayed_work() From: Oleg Nesterov <oleg@xxxxxxxxxx> We should not use cancel_work_sync(delayed_work->work). This works, but not good. We can use cancel_rearming_delayed_work(), this also simplifies the code. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/ata/libata-core.c | 44 +++--------------------------------- include/linux/libata.h | 1 2 files changed, 4 insertions(+), 41 deletions(-) diff -puN drivers/ata/libata-core.c~libata-core-convert-to-use-cancel_rearming_delayed_work drivers/ata/libata-core.c --- a/drivers/ata/libata-core.c~libata-core-convert-to-use-cancel_rearming_delayed_work +++ a/drivers/ata/libata-core.c @@ -1286,18 +1286,11 @@ static unsigned int ata_id_xfermask(cons void ata_port_queue_task(struct ata_port *ap, work_func_t fn, void *data, unsigned long delay) { - int rc; - - if (ap->pflags & ATA_PFLAG_FLUSH_PORT_TASK) - return; - PREPARE_DELAYED_WORK(&ap->port_task, fn); ap->port_task_data = data; - rc = queue_delayed_work(ata_wq, &ap->port_task, delay); - - /* rc == 0 means that another user is using port task */ - WARN_ON(rc == 0); + /* may fail if ata_port_flush_task() in progress */ + queue_delayed_work(ata_wq, &ap->port_task, delay); } /** @@ -1312,32 +1305,9 @@ void ata_port_queue_task(struct ata_port */ void ata_port_flush_task(struct ata_port *ap) { - unsigned long flags; - DPRINTK("ENTER\n"); - spin_lock_irqsave(ap->lock, flags); - ap->pflags |= ATA_PFLAG_FLUSH_PORT_TASK; - spin_unlock_irqrestore(ap->lock, flags); - - DPRINTK("flush #1\n"); - cancel_work_sync(&ap->port_task.work); /* akpm: seems unneeded */ - - /* - * At this point, if a task is running, it's guaranteed to see - * the FLUSH flag; thus, it will never queue pio tasks again. - * Cancel and flush. - */ - if (!cancel_delayed_work(&ap->port_task)) { - if (ata_msg_ctl(ap)) - ata_port_printk(ap, KERN_DEBUG, "%s: flush #2\n", - __FUNCTION__); - cancel_work_sync(&ap->port_task.work); - } - - spin_lock_irqsave(ap->lock, flags); - ap->pflags &= ~ATA_PFLAG_FLUSH_PORT_TASK; - spin_unlock_irqrestore(ap->lock, flags); + cancel_rearming_delayed_work(&ap->port_task); if (ata_msg_ctl(ap)) ata_port_printk(ap, KERN_DEBUG, "%s: EXIT\n", __FUNCTION__); @@ -6518,13 +6488,7 @@ void ata_port_detach(struct ata_port *ap spin_unlock_irqrestore(ap->lock, flags); ata_port_wait_eh(ap); - - /* Flush hotplug task. The sequence is similar to - * ata_port_flush_task(). - */ - cancel_work_sync(&ap->hotplug_task.work); /* akpm: why? */ - cancel_delayed_work(&ap->hotplug_task); - cancel_work_sync(&ap->hotplug_task.work); + cancel_rearming_delayed_work(&ap->hotplug_task); skip_eh: /* remove the associated SCSI host */ diff -puN include/linux/libata.h~libata-core-convert-to-use-cancel_rearming_delayed_work include/linux/libata.h --- a/include/linux/libata.h~libata-core-convert-to-use-cancel_rearming_delayed_work +++ a/include/linux/libata.h @@ -193,7 +193,6 @@ enum { ATA_PFLAG_SCSI_HOTPLUG = (1 << 6), /* SCSI hotplug scheduled */ ATA_PFLAG_INITIALIZING = (1 << 7), /* being initialized, don't touch */ - ATA_PFLAG_FLUSH_PORT_TASK = (1 << 16), /* flush port task */ ATA_PFLAG_SUSPENDED = (1 << 17), /* port is suspended (power) */ ATA_PFLAG_PM_PENDING = (1 << 18), /* PM operation pending */ _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are origin.patch allow-access-to-proc-pid-fd-after-setuid.patch freezer-task-exit_state-should-be-treated-as-bolean.patch softlockup-trivial-s-99-max_rt_prio.patch merge-sys_clone-sys_unshare-nsproxy-and-namespace.patch fix-race-between-proc_get_inode-and-remove_proc_entry.patch futex-restartable-futex_wait.patch add-support-for-deferrable-timers-respun.patch add-a-new-deferrable-delayed-work-init.patch clone-flag-clone_parent_tidptr-leaves-invalid-results-in-memory.patch getrusage-fill-ru_inblock-and-ru_oublock-fields-if-possible.patch reimplement-flush_workqueue.patch implement-flush_work.patch flush_workqueue-use-preempt_disable-to-hold-off-cpu-hotplug.patch flush_cpu_workqueue-dont-flush-an-empty-worklist.patch aio-use-flush_work.patch kblockd-use-flush_work.patch relayfs-use-flush_keventd_work.patch tg3-use-flush_keventd_work.patch e1000-use-flush_keventd_work.patch libata-use-flush_work.patch phy-use-flush_work.patch call-cpu_chain-with-cpu_down_failed-if-cpu_down_prepare-failed.patch slab-use-cpu_lock_.patch workqueue-fix-freezeable-workqueues-implementation.patch workqueue-fix-flush_workqueue-vs-cpu_dead-race.patch workqueue-dont-clear-cwq-thread-until-it-exits.patch workqueue-dont-migrate-pending-works-from-the-dead-cpu.patch workqueue-kill-run_scheduled_work.patch workqueue-dont-save-interrupts-in-run_workqueue.patch workqueue-make-cancel_rearming_delayed_workqueue-work-on-idle-dwork.patch workqueue-introduce-cpu_singlethread_map.patch workqueue-introduce-workqueue_struct-singlethread.patch workqueue-make-init_workqueues-__init.patch workqueues-shift-kthread_bind-from-cpu_up_prepare-to-cpu_online.patch make-queue_delayed_work-friendly-to-flush_fork.patch unify-queue_delayed_work-and-queue_delayed_work_on.patch workqueue-introduce-wq_per_cpu-helper.patch make-cancel_rearming_delayed_work-work-on-any-workqueue-not-just-keventd_wq.patch ipvs-flush-defense_work-before-module-unload.patch workqueue-kill-noautorel-works.patch worker_thread-dont-play-with-signals.patch worker_thread-fix-racy-try_to_freeze-usage.patch zap_other_threads-remove-unneeded-exit_signal-change.patch slab-shutdown-cache_reaper-when-cpu-goes-down.patch unify-flush_work-flush_work_keventd-and-rename-it-to-cancel_work_sync.patch ____call_usermodehelper-dont-flush_signals.patch freezer-read-pf_borrowed_mm-in-a-nonracy-way.patch freezer-close-theoretical-race-between-refrigerator-and-thaw_tasks.patch freezer-remove-pf_nofreeze-from-rcutorture-thread.patch freezer-remove-pf_nofreeze-from-bluetooth-threads.patch freezer-add-try_to_freeze-calls-to-all-kernel-threads.patch freezer-fix-vfork-problem.patch freezer-take-kernel_execve-into-consideration.patch kthread-dont-depend-on-work-queues-take-2.patch change-reparent_to_init-to-reparent_to_kthreadd.patch nlmclnt_recovery-dont-use-clone_sighand.patch usbatm_heavy_init-dont-use-clone_sighand.patch wait_for_helper-remove-unneeded-do_sigaction.patch worker_thread-dont-play-with-sigchld-and-numa-policy.patch change-kernel-threads-to-ignore-signals-instead-of-blocking-them.patch fix-kthread_create-vs-freezer-theoretical-race.patch fix-pf_nofreeze-and-freezeable-race-2.patch freezer-document-task_lock-in-thaw_process.patch move-frozen_process-to-kernel-power-processc.patch remvoe-kthread_bind-call-from-_cpu_down.patch separate-freezer-from-pm-code-rev-2.patch introduce-freezer-flags-rev-2.patch make-cancel_rearming_delayed_work-reliable.patch make-cancel_rearming_delayed_work-reliable-spelling.patch make-cancel_rearming_delayed_work-reliable-fix.patch libata-core-convert-to-use-cancel_rearming_delayed_work.patch dont-init-pgrp-and-__session-in-init_signals.patch add-suspend-related-notifications-for-cpu-hotplug-cleanup.patch vmstat-use-our-own-timer-events-fix.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html