diff options
Diffstat (limited to 'kernel/workqueue.c')
| -rw-r--r-- | kernel/workqueue.c | 91 |
1 files changed, 75 insertions, 16 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index eebb1d83923..835fe28b87a 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -68,7 +68,7 @@ struct workqueue_struct { /* All the per-cpu workqueues on the system, for hotplug cpu to add/remove threads to each one as cpus come/go. */ -static DEFINE_SPINLOCK(workqueue_lock); +static DEFINE_MUTEX(workqueue_mutex); static LIST_HEAD(workqueues); static int singlethread_cpu; @@ -93,9 +93,12 @@ static void __queue_work(struct cpu_workqueue_struct *cwq, spin_unlock_irqrestore(&cwq->lock, flags); } -/* - * Queue work on a workqueue. Return non-zero if it was successfully - * added. +/** + * queue_work - queue work on a workqueue + * @wq: workqueue to use + * @work: work to queue + * + * Returns non-zero if it was successfully added. * * We queue the work to the CPU it was submitted, but there is no * guarantee that it will be processed by that CPU. @@ -128,6 +131,14 @@ static void delayed_work_timer_fn(unsigned long __data) __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work); } +/** + * queue_delayed_work - queue work on a workqueue after delay + * @wq: workqueue to use + * @work: work to queue + * @delay: number of jiffies to wait before queueing + * + * Returns non-zero if it was successfully added. + */ int fastcall queue_delayed_work(struct workqueue_struct *wq, struct work_struct *work, unsigned long delay) { @@ -150,6 +161,15 @@ int fastcall queue_delayed_work(struct workqueue_struct *wq, } EXPORT_SYMBOL_GPL(queue_delayed_work); +/** + * queue_delayed_work_on - queue work on specific CPU after delay + * @cpu: CPU number to execute work on + * @wq: workqueue to use + * @work: work to queue + * @delay: number of jiffies to wait before queueing + * + * Returns non-zero if it was successfully added. + */ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work, unsigned long delay) { @@ -275,8 +295,9 @@ static void flush_cpu_workqueue(struct cpu_workqueue_struct *cwq) } } -/* +/** * flush_workqueue - ensure that any scheduled work has run to completion. + * @wq: workqueue to flush * * Forces execution of the workqueue and blocks until its completion. * This is typically used in driver shutdown handlers. @@ -299,10 +320,10 @@ void fastcall flush_workqueue(struct workqueue_struct *wq) } else { int cpu; - lock_cpu_hotplug(); + mutex_lock(&workqueue_mutex); for_each_online_cpu(cpu) flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, cpu)); - unlock_cpu_hotplug(); + mutex_unlock(&workqueue_mutex); } } EXPORT_SYMBOL_GPL(flush_workqueue); @@ -350,8 +371,7 @@ struct workqueue_struct *__create_workqueue(const char *name, } wq->name = name; - /* We don't need the distraction of CPUs appearing and vanishing. */ - lock_cpu_hotplug(); + mutex_lock(&workqueue_mutex); if (singlethread) { INIT_LIST_HEAD(&wq->list); p = create_workqueue_thread(wq, singlethread_cpu); @@ -360,9 +380,7 @@ struct workqueue_struct *__create_workqueue(const char *name, else wake_up_process(p); } else { - spin_lock(&workqueue_lock); list_add(&wq->list, &workqueues); - spin_unlock(&workqueue_lock); for_each_online_cpu(cpu) { p = create_workqueue_thread(wq, cpu); if (p) { @@ -372,7 +390,7 @@ struct workqueue_struct *__create_workqueue(const char *name, destroy = 1; } } - unlock_cpu_hotplug(); + mutex_unlock(&workqueue_mutex); /* * Was there any error during startup? If yes then clean up: @@ -400,6 +418,12 @@ static void cleanup_workqueue_thread(struct workqueue_struct *wq, int cpu) kthread_stop(p); } +/** + * destroy_workqueue - safely terminate a workqueue + * @wq: target workqueue + * + * Safely destroy a workqueue. All work currently pending will be done first. + */ void destroy_workqueue(struct workqueue_struct *wq) { int cpu; @@ -407,17 +431,15 @@ void destroy_workqueue(struct workqueue_struct *wq) flush_workqueue(wq); /* We don't need the distraction of CPUs appearing and vanishing. */ - lock_cpu_hotplug(); + mutex_lock(&workqueue_mutex); if (is_single_threaded(wq)) cleanup_workqueue_thread(wq, singlethread_cpu); else { for_each_online_cpu(cpu) cleanup_workqueue_thread(wq, cpu); - spin_lock(&workqueue_lock); list_del(&wq->list); - spin_unlock(&workqueue_lock); } - unlock_cpu_hotplug(); + mutex_unlock(&workqueue_mutex); free_percpu(wq->cpu_wq); kfree(wq); } @@ -425,18 +447,41 @@ EXPORT_SYMBOL_GPL(destroy_workqueue); static struct workqueue_struct *keventd_wq; +/** + * schedule_work - put work task in global workqueue + * @work: job to be done + * + * This puts a job in the kernel-global workqueue. + */ int fastcall schedule_work(struct work_struct *work) { return queue_work(keventd_wq, work); } EXPORT_SYMBOL(schedule_work); +/** + * schedule_delayed_work - put work task in global workqueue after delay + * @work: job to be done + * @delay: number of jiffies to wait + * + * After waiting for a given time this puts a job in the kernel-global + * workqueue. + */ int fastcall schedule_delayed_work(struct work_struct *work, unsigned long delay) { return queue_delayed_work(keventd_wq, work, delay); } EXPORT_SYMBOL(schedule_delayed_work); +/** + * schedule_delayed_work_on - queue work in global workqueue on CPU after delay + * @cpu: cpu to use + * @work: job to be done + * @delay: number of jiffies to wait + * + * After waiting for a given time this puts a job in the kernel-global + * workqueue on the specified CPU. + */ int schedule_delayed_work_on(int cpu, struct work_struct *work, unsigned long delay) { @@ -465,11 +510,13 @@ int schedule_on_each_cpu(void (*func)(void *info), void *info) if (!works) return -ENOMEM; + mutex_lock(&workqueue_mutex); for_each_online_cpu(cpu) { INIT_WORK(per_cpu_ptr(works, cpu), func, info); __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), per_cpu_ptr(works, cpu)); } + mutex_unlock(&workqueue_mutex); flush_workqueue(keventd_wq); free_percpu(works); return 0; @@ -585,6 +632,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, switch (action) { case CPU_UP_PREPARE: + mutex_lock(&workqueue_mutex); /* Create a new workqueue thread for it. */ list_for_each_entry(wq, &workqueues, list) { if (!create_workqueue_thread(wq, hotcpu)) { @@ -603,6 +651,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, kthread_bind(cwq->thread, hotcpu); wake_up_process(cwq->thread); } + mutex_unlock(&workqueue_mutex); break; case CPU_UP_CANCELED: @@ -614,6 +663,15 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, any_online_cpu(cpu_online_map)); cleanup_workqueue_thread(wq, hotcpu); } + mutex_unlock(&workqueue_mutex); + break; + + case CPU_DOWN_PREPARE: + mutex_lock(&workqueue_mutex); + break; + + case CPU_DOWN_FAILED: + mutex_unlock(&workqueue_mutex); break; case CPU_DEAD: @@ -621,6 +679,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, cleanup_workqueue_thread(wq, hotcpu); list_for_each_entry(wq, &workqueues, list) take_over_work(wq, hotcpu); + mutex_unlock(&workqueue_mutex); break; } |