diff options
| -rw-r--r-- | drivers/block/floppy.c | 4 | ||||
| -rw-r--r-- | include/linux/workqueue.h | 27 | ||||
| -rw-r--r-- | kernel/workqueue.c | 41 |
3 files changed, 57 insertions, 15 deletions
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 5a14fac..aa1eb44 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -1868,7 +1868,7 @@ static void show_floppy(void) printk("fdc_busy=%lu\n", fdc_busy); if (do_floppy) printk("do_floppy=%p\n", do_floppy); - if (floppy_work.pending) + if (work_pending(&floppy_work)) printk("floppy_work.func=%p\n", floppy_work.func); if (timer_pending(&fd_timer)) printk("fd_timer.function=%p\n", fd_timer.function); @@ -4498,7 +4498,7 @@ static void floppy_release_irq_and_dma(void) printk("floppy timer still active:%s\n", timeout_message); if (timer_pending(&fd_timer)) printk("auxiliary floppy timer still active\n"); - if (floppy_work.pending) + if (work_pending(&floppy_work)) printk("work still pending\n"); #endif old_fdc = fdc; diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index cef40b2..ecc017d 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -14,11 +14,15 @@ struct workqueue_struct; typedef void (*work_func_t)(void *data); struct work_struct { - unsigned long pending; + /* the first word is the work queue pointer and the pending flag + * rolled into one */ + unsigned long management; +#define WORK_STRUCT_PENDING 0 /* T if work item pending execution */ +#define WORK_STRUCT_FLAG_MASK (3UL) +#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK) struct list_head entry; work_func_t func; void *data; - void *wq_data; }; struct delayed_work { @@ -65,7 +69,7 @@ struct execute_work { #define INIT_WORK(_work, _func, _data) \ do { \ INIT_LIST_HEAD(&(_work)->entry); \ - (_work)->pending = 0; \ + (_work)->management = 0; \ PREPARE_WORK((_work), (_func), (_data)); \ } while (0) @@ -75,6 +79,21 @@ struct execute_work { init_timer(&(_work)->timer); \ } while (0) +/** + * work_pending - Find out whether a work item is currently pending + * @work: The work item in question + */ +#define work_pending(work) \ + test_bit(WORK_STRUCT_PENDING, &(work)->management) + +/** + * delayed_work_pending - Find out whether a delayable work item is currently + * pending + * @work: The work item in question + */ +#define delayed_work_pending(work) \ + test_bit(WORK_STRUCT_PENDING, &(work)->work.management) + extern struct workqueue_struct *__create_workqueue(const char *name, int singlethread); @@ -115,7 +134,7 @@ static inline int cancel_delayed_work(struct delayed_work *work) ret = del_timer_sync(&work->timer); if (ret) - clear_bit(0, &work->work.pending); + clear_bit(WORK_STRUCT_PENDING, &work->work.management); return ret; } diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 1e9d61e..9674797 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -80,6 +80,29 @@ static inline int is_single_threaded(struct workqueue_struct *wq) return list_empty(&wq->list); } +static inline void set_wq_data(struct work_struct *work, void *wq) +{ + unsigned long new, old, res; + + /* assume the pending flag is already set and that the task has already + * been queued on this workqueue */ + new = (unsigned long) wq | (1UL << WORK_STRUCT_PENDING); + res = work->management; + if (res != new) { + do { + old = res; + new = (unsigned long) wq; + new |= (old & WORK_STRUCT_FLAG_MASK); + res = cmpxchg(&work->management, old, new); + } while (res != old); + } +} + +static inline void *get_wq_data(struct work_struct *work) +{ + return (void *) (work->management & WORK_STRUCT_WQ_DATA_MASK); +} + /* Preempt must be disabled. */ static void __queue_work(struct cpu_workqueue_struct *cwq, struct work_struct *work) @@ -87,7 +110,7 @@ static void __queue_work(struct cpu_workqueue_struct *cwq, unsigned long flags; spin_lock_irqsave(&cwq->lock, flags); - work->wq_data = cwq; + set_wq_data(work, cwq); list_add_tail(&work->entry, &cwq->worklist); cwq->insert_sequence++; wake_up(&cwq->more_work); @@ -108,7 +131,7 @@ int fastcall queue_work(struct workqueue_struct *wq, struct work_struct *work) { int ret = 0, cpu = get_cpu(); - if (!test_and_set_bit(0, &work->pending)) { + if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) { if (unlikely(is_single_threaded(wq))) cpu = singlethread_cpu; BUG_ON(!list_empty(&work->entry)); @@ -123,7 +146,7 @@ EXPORT_SYMBOL_GPL(queue_work); static void delayed_work_timer_fn(unsigned long __data) { struct delayed_work *dwork = (struct delayed_work *)__data; - struct workqueue_struct *wq = dwork->work.wq_data; + struct workqueue_struct *wq = get_wq_data(&dwork->work); int cpu = smp_processor_id(); if (unlikely(is_single_threaded(wq))) @@ -150,12 +173,12 @@ int fastcall queue_delayed_work(struct workqueue_struct *wq, if (delay == 0) return queue_work(wq, work); - if (!test_and_set_bit(0, &work->pending)) { + if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) { 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; + set_wq_data(work, wq); timer->expires = jiffies + delay; timer->data = (unsigned long)dwork; timer->function = delayed_work_timer_fn; @@ -182,12 +205,12 @@ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq, struct timer_list *timer = &dwork->timer; struct work_struct *work = &dwork->work; - if (!test_and_set_bit(0, &work->pending)) { + if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) { 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; + set_wq_data(work, wq); timer->expires = jiffies + delay; timer->data = (unsigned long)dwork; timer->function = delayed_work_timer_fn; @@ -223,8 +246,8 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq) list_del_init(cwq->worklist.next); spin_unlock_irqrestore(&cwq->lock, flags); - BUG_ON(work->wq_data != cwq); - clear_bit(0, &work->pending); + BUG_ON(get_wq_data(work) != cwq); + clear_bit(WORK_STRUCT_PENDING, &work->management); f(data); spin_lock_irqsave(&cwq->lock, flags); |