diff options
| -rw-r--r-- | include/linux/workqueue.h | 4 | ||||
| -rw-r--r-- | kernel/workqueue.c | 41 |
2 files changed, 29 insertions, 16 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 5c89ac6e7f55..ce6badc98f6d 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -148,7 +148,7 @@ extern int keventd_up(void); extern void init_workqueues(void); int execute_in_process_context(work_func_t fn, struct execute_work *); -extern void cancel_work_sync(struct work_struct *work); +extern int cancel_work_sync(struct work_struct *work); /* * Kill off a pending schedule_delayed_work(). Note that the work callback @@ -166,7 +166,7 @@ static inline int cancel_delayed_work(struct delayed_work *work) return ret; } -extern void cancel_delayed_work_sync(struct delayed_work *work); +extern int cancel_delayed_work_sync(struct delayed_work *work); /* Obsolete. use cancel_delayed_work_sync() */ static inline diff --git a/kernel/workqueue.c b/kernel/workqueue.c index ad9656886daa..d7d3fa3072e5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -382,16 +382,16 @@ void fastcall flush_workqueue(struct workqueue_struct *wq) EXPORT_SYMBOL_GPL(flush_workqueue); /* - * Upon a successful return, the caller "owns" WORK_STRUCT_PENDING bit, + * Upon a successful return (>= 0), the caller "owns" WORK_STRUCT_PENDING bit, * so this work can't be re-armed in any way. */ static int try_to_grab_pending(struct work_struct *work) { struct cpu_workqueue_struct *cwq; - int ret = 0; + int ret = -1; if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) - return 1; + return 0; /* * The queueing is in progress, or it is already queued. Try to @@ -457,10 +457,28 @@ static void wait_on_work(struct work_struct *work) wait_on_cpu_work(per_cpu_ptr(wq->cpu_wq, cpu), work); } +static int __cancel_work_timer(struct work_struct *work, + struct timer_list* timer) +{ + int ret; + + do { + ret = (timer && likely(del_timer(timer))); + if (!ret) + ret = try_to_grab_pending(work); + wait_on_work(work); + } while (unlikely(ret < 0)); + + work_clear_pending(work); + return ret; +} + /** * cancel_work_sync - block until a work_struct's callback has terminated * @work: the work which is to be flushed * + * Returns true if @work was pending. + * * cancel_work_sync() will cancel the work if it is queued. If the work's * callback appears to be running, cancel_work_sync() will block until it * has completed. @@ -476,12 +494,9 @@ static void wait_on_work(struct work_struct *work) * The caller must ensure that workqueue_struct on which this work was last * queued can't be destroyed before this function returns. */ -void cancel_work_sync(struct work_struct *work) +int cancel_work_sync(struct work_struct *work) { - while (!try_to_grab_pending(work)) - cpu_relax(); - wait_on_work(work); - work_clear_pending(work); + return __cancel_work_timer(work, NULL); } EXPORT_SYMBOL_GPL(cancel_work_sync); @@ -489,16 +504,14 @@ EXPORT_SYMBOL_GPL(cancel_work_sync); * cancel_delayed_work_sync - reliably kill off a delayed work. * @dwork: the delayed work struct * + * Returns true if @dwork was pending. + * * It is possible to use this function if @dwork rearms itself via queue_work() * or queue_delayed_work(). See also the comment for cancel_work_sync(). */ -void cancel_delayed_work_sync(struct delayed_work *dwork) +int cancel_delayed_work_sync(struct delayed_work *dwork) { - while (!del_timer(&dwork->timer) && - !try_to_grab_pending(&dwork->work)) - cpu_relax(); - wait_on_work(&dwork->work); - work_clear_pending(&dwork->work); + return __cancel_work_timer(&dwork->work, &dwork->timer); } EXPORT_SYMBOL(cancel_delayed_work_sync); |