diff options
| -rw-r--r-- | share/man/man9/taskqueue.9 | 2 | ||||
| -rw-r--r-- | sys/kern/subr_taskqueue.c | 23 |
2 files changed, 24 insertions, 1 deletions
diff --git a/share/man/man9/taskqueue.9 b/share/man/man9/taskqueue.9 index 910b33e..4391a18 100644 --- a/share/man/man9/taskqueue.9 +++ b/share/man/man9/taskqueue.9 @@ -221,6 +221,8 @@ Otherwise, the task is scheduled for enqueueing in the future, after the absolute value of .Va ticks is passed. +This function returns -1 if the task is being drained. +Otherwise, the number of pending calls is returned. .Pp The .Fn taskqueue_cancel diff --git a/sys/kern/subr_taskqueue.c b/sys/kern/subr_taskqueue.c index c9addb1..ef090bb 100644 --- a/sys/kern/subr_taskqueue.c +++ b/sys/kern/subr_taskqueue.c @@ -75,6 +75,7 @@ struct taskqueue { #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) #define DT_CALLOUT_ARMED (1 << 0) +#define DT_DRAIN_IN_PROGRESS (1 << 1) #define TQ_LOCK(tq) \ do { \ @@ -279,7 +280,11 @@ taskqueue_enqueue_timeout(struct taskqueue *queue, KASSERT(!queue->tq_spin, ("Timeout for spin-queue")); timeout_task->q = queue; res = timeout_task->t.ta_pending; - if (ticks == 0) { + if (timeout_task->f & DT_DRAIN_IN_PROGRESS) { + /* Do nothing */ + TQ_UNLOCK(queue); + res = -1; + } else if (ticks == 0) { taskqueue_enqueue_locked(queue, &timeout_task->t); /* The lock is released inside. */ } else { @@ -485,8 +490,24 @@ taskqueue_drain_timeout(struct taskqueue *queue, struct timeout_task *timeout_task) { + /* + * Set flag to prevent timer from re-starting during drain: + */ + TQ_LOCK(queue); + KASSERT((timeout_task->f & DT_DRAIN_IN_PROGRESS) == 0, + ("Drain already in progress")); + timeout_task->f |= DT_DRAIN_IN_PROGRESS; + TQ_UNLOCK(queue); + callout_drain(&timeout_task->c); taskqueue_drain(queue, &timeout_task->t); + + /* + * Clear flag to allow timer to re-start: + */ + TQ_LOCK(queue); + timeout_task->f &= ~DT_DRAIN_IN_PROGRESS; + TQ_UNLOCK(queue); } static void |
