X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fworkqueue.c;h=835fe28b87a8325c1cfb691de03dd7e2615ea943;hb=546e0d271941dd1ff6961e2a1f7eac75f1fc277e;hp=880fb415a8f601ebb5fff636fee20b958fe71149;hpb=35a5d9ed9fedb74c22cb19ff7d749289473144e0;p=linux-2.6-omap-h63xx.git diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 880fb415a8f..835fe28b87a 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -51,7 +51,7 @@ struct cpu_workqueue_struct { wait_queue_head_t work_done; struct workqueue_struct *wq; - task_t *thread; + struct task_struct *thread; int run_depth; /* Detect run_workqueue() recursion depth */ } ____cacheline_aligned; @@ -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. @@ -114,6 +117,7 @@ int fastcall queue_work(struct workqueue_struct *wq, struct work_struct *work) put_cpu(); return ret; } +EXPORT_SYMBOL_GPL(queue_work); static void delayed_work_timer_fn(unsigned long __data) { @@ -127,6 +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) { @@ -147,6 +159,38 @@ int fastcall queue_delayed_work(struct workqueue_struct *wq, } return ret; } +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) +{ + int ret = 0; + struct timer_list *timer = &work->timer; + + if (!test_and_set_bit(0, &work->pending)) { + BUG_ON(timer_pending(timer)); + BUG_ON(!list_empty(&work->entry)); + + /* This stores wq for the moment, for the timer_fn */ + work->wq_data = wq; + timer->expires = jiffies + delay; + timer->data = (unsigned long)work; + timer->function = delayed_work_timer_fn; + add_timer_on(timer, cpu); + ret = 1; + } + return ret; +} +EXPORT_SYMBOL_GPL(queue_delayed_work_on); static void run_workqueue(struct cpu_workqueue_struct *cwq) { @@ -251,8 +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. @@ -275,12 +320,13 @@ 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); static struct task_struct *create_workqueue_thread(struct workqueue_struct *wq, int cpu) @@ -325,8 +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); @@ -335,9 +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) { @@ -347,7 +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: @@ -358,6 +401,7 @@ struct workqueue_struct *__create_workqueue(const char *name, } return wq; } +EXPORT_SYMBOL_GPL(__create_workqueue); static void cleanup_workqueue_thread(struct workqueue_struct *wq, int cpu) { @@ -374,6 +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; @@ -381,69 +431,94 @@ 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); } +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) { - int ret = 0; - struct timer_list *timer = &work->timer; - - if (!test_and_set_bit(0, &work->pending)) { - BUG_ON(timer_pending(timer)); - BUG_ON(!list_empty(&work->entry)); - /* This stores keventd_wq for the moment, for the timer_fn */ - work->wq_data = keventd_wq; - timer->expires = jiffies + delay; - timer->data = (unsigned long)work; - timer->function = delayed_work_timer_fn; - add_timer_on(timer, cpu); - ret = 1; - } - return ret; + return queue_delayed_work_on(cpu, keventd_wq, work, delay); } +EXPORT_SYMBOL(schedule_delayed_work_on); -int schedule_on_each_cpu(void (*func) (void *info), void *info) +/** + * schedule_on_each_cpu - call a function on each online CPU from keventd + * @func: the function to call + * @info: a pointer to pass to func() + * + * Returns zero on success. + * Returns -ve errno on failure. + * + * Appears to be racy against CPU hotplug. + * + * schedule_on_each_cpu() is very slow. + */ +int schedule_on_each_cpu(void (*func)(void *info), void *info) { int cpu; - struct work_struct *work; - - work = kmalloc(NR_CPUS * sizeof(struct work_struct), GFP_KERNEL); + struct work_struct *works; - if (!work) + works = alloc_percpu(struct work_struct); + if (!works) return -ENOMEM; + + mutex_lock(&workqueue_mutex); for_each_online_cpu(cpu) { - INIT_WORK(work + cpu, func, info); + INIT_WORK(per_cpu_ptr(works, cpu), func, info); __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), - work + cpu); + per_cpu_ptr(works, cpu)); } + mutex_unlock(&workqueue_mutex); flush_workqueue(keventd_wq); - kfree(work); + free_percpu(works); return 0; } @@ -451,6 +526,7 @@ void flush_scheduled_work(void) { flush_workqueue(keventd_wq); } +EXPORT_SYMBOL(flush_scheduled_work); /** * cancel_rearming_delayed_workqueue - reliably kill off a delayed @@ -531,11 +607,11 @@ int current_is_keventd(void) static void take_over_work(struct workqueue_struct *wq, unsigned int cpu) { struct cpu_workqueue_struct *cwq = per_cpu_ptr(wq->cpu_wq, cpu); - LIST_HEAD(list); + struct list_head list; struct work_struct *work; spin_lock_irq(&cwq->lock); - list_splice_init(&cwq->worklist, &list); + list_replace_init(&cwq->worklist, &list); while (!list_empty(&list)) { printk("Taking work for %s\n", wq->name); @@ -547,7 +623,7 @@ static void take_over_work(struct workqueue_struct *wq, unsigned int cpu) } /* We're holding the cpucontrol mutex here */ -static int workqueue_cpu_callback(struct notifier_block *nfb, +static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { @@ -556,6 +632,7 @@ static int 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)) { @@ -574,15 +651,27 @@ static int 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: list_for_each_entry(wq, &workqueues, list) { + if (!per_cpu_ptr(wq->cpu_wq, hotcpu)->thread) + continue; /* Unbind so it can run. */ kthread_bind(per_cpu_ptr(wq->cpu_wq, hotcpu)->thread, 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: @@ -590,6 +679,7 @@ static int 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; } @@ -605,13 +695,3 @@ void init_workqueues(void) BUG_ON(!keventd_wq); } -EXPORT_SYMBOL_GPL(__create_workqueue); -EXPORT_SYMBOL_GPL(queue_work); -EXPORT_SYMBOL_GPL(queue_delayed_work); -EXPORT_SYMBOL_GPL(flush_workqueue); -EXPORT_SYMBOL_GPL(destroy_workqueue); - -EXPORT_SYMBOL(schedule_work); -EXPORT_SYMBOL(schedule_delayed_work); -EXPORT_SYMBOL(schedule_delayed_work_on); -EXPORT_SYMBOL(flush_scheduled_work);