return list_empty(&wq->list);
}
+/*
+ * Set the workqueue on which a work item is to be run
+ * - Must *only* be called if the pending flag is set
+ */
static inline void set_wq_data(struct work_struct *work, void *wq)
{
- unsigned long new, old, res;
+ unsigned long new;
+
+ BUG_ON(!work_pending(work));
- /* 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);
- }
+ new |= WORK_STRUCT_FLAG_MASK & *work_data_bits(work);
+ atomic_long_set(&work->data, new);
}
static inline void *get_wq_data(struct work_struct *work)
{
- return (void *) (work->management & WORK_STRUCT_WQ_DATA_MASK);
+ return (void *) (atomic_long_read(&work->data) & WORK_STRUCT_WQ_DATA_MASK);
+}
+
+static int __run_work(struct cpu_workqueue_struct *cwq, struct work_struct *work)
+{
+ int ret = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&cwq->lock, flags);
+ /*
+ * We need to re-validate the work info after we've gotten
+ * the cpu_workqueue lock. We can run the work now iff:
+ *
+ * - the wq_data still matches the cpu_workqueue_struct
+ * - AND the work is still marked pending
+ * - AND the work is still on a list (which will be this
+ * workqueue_struct list)
+ *
+ * All these conditions are important, because we
+ * need to protect against the work being run right
+ * now on another CPU (all but the last one might be
+ * true if it's currently running and has not been
+ * released yet, for example).
+ */
+ if (get_wq_data(work) == cwq
+ && work_pending(work)
+ && !list_empty(&work->entry)) {
+ work_func_t f = work->func;
+ list_del_init(&work->entry);
+ spin_unlock_irqrestore(&cwq->lock, flags);
+
+ if (!test_bit(WORK_STRUCT_NOAUTOREL, work_data_bits(work)))
+ work_release(work);
+ f(work);
+
+ spin_lock_irqsave(&cwq->lock, flags);
+ cwq->remove_sequence++;
+ wake_up(&cwq->work_done);
+ ret = 1;
+ }
+ spin_unlock_irqrestore(&cwq->lock, flags);
+ return ret;
+}
+
+/**
+ * run_scheduled_work - run scheduled work synchronously
+ * @work: work to run
+ *
+ * This checks if the work was pending, and runs it
+ * synchronously if so. It returns a boolean to indicate
+ * whether it had any scheduled work to run or not.
+ *
+ * NOTE! This _only_ works for normal work_structs. You
+ * CANNOT use this for delayed work, because the wq data
+ * for delayed work will not point properly to the per-
+ * CPU workqueue struct, but will change!
+ */
+int fastcall run_scheduled_work(struct work_struct *work)
+{
+ for (;;) {
+ struct cpu_workqueue_struct *cwq;
+
+ if (!work_pending(work))
+ return 0;
+ if (list_empty(&work->entry))
+ return 0;
+ /* NOTE! This depends intimately on __queue_work! */
+ cwq = get_wq_data(work);
+ if (!cwq)
+ return 0;
+ if (__run_work(cwq, work))
+ return 1;
+ }
}
+EXPORT_SYMBOL(run_scheduled_work);
/* Preempt must be disabled. */
static void __queue_work(struct cpu_workqueue_struct *cwq,
{
int ret = 0, cpu = get_cpu();
- if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) {
+ if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
if (unlikely(is_single_threaded(wq)))
cpu = singlethread_cpu;
BUG_ON(!list_empty(&work->entry));
/**
* queue_delayed_work - queue work on a workqueue after delay
* @wq: workqueue to use
- * @work: delayable work to queue
+ * @dwork: delayable work to queue
* @delay: number of jiffies to wait before queueing
*
* Returns 0 if @work was already on a queue, non-zero otherwise.
if (delay == 0)
return queue_work(wq, work);
- if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) {
+ if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
BUG_ON(timer_pending(timer));
BUG_ON(!list_empty(&work->entry));
* 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
+ * @dwork: work to queue
* @delay: number of jiffies to wait before queueing
*
* Returns 0 if @work was already on a queue, non-zero otherwise.
struct timer_list *timer = &dwork->timer;
struct work_struct *work = &dwork->work;
- if (!test_and_set_bit(WORK_STRUCT_PENDING, &work->management)) {
+ if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
BUG_ON(timer_pending(timer));
BUG_ON(!list_empty(&work->entry));
spin_unlock_irqrestore(&cwq->lock, flags);
BUG_ON(get_wq_data(work) != cwq);
- if (!test_bit(WORK_STRUCT_NOAUTOREL, &work->management))
+ if (!test_bit(WORK_STRUCT_NOAUTOREL, work_data_bits(work)))
work_release(work);
f(work);
mutex_lock(&workqueue_mutex);
for_each_online_cpu(cpu) {
- INIT_WORK(per_cpu_ptr(works, cpu), func);
- __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu),
- per_cpu_ptr(works, cpu));
+ struct work_struct *work = per_cpu_ptr(works, cpu);
+
+ INIT_WORK(work, func);
+ set_bit(WORK_STRUCT_PENDING, work_data_bits(work));
+ __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), work);
}
mutex_unlock(&workqueue_mutex);
flush_workqueue(keventd_wq);
EXPORT_SYMBOL(flush_scheduled_work);
/**
- * cancel_rearming_delayed_workqueue - reliably kill off a delayed
- * work whose handler rearms the delayed work.
+ * cancel_rearming_delayed_workqueue - reliably kill off a delayed work whose handler rearms the delayed work.
* @wq: the controlling workqueue structure
* @dwork: the delayed work struct
*/
EXPORT_SYMBOL(cancel_rearming_delayed_workqueue);
/**
- * cancel_rearming_delayed_work - reliably kill off a delayed keventd
- * work whose handler rearms the delayed work.
+ * cancel_rearming_delayed_work - reliably kill off a delayed keventd work whose handler rearms the delayed work.
* @dwork: the delayed work struct
*/
void cancel_rearming_delayed_work(struct delayed_work *dwork)