FreeBSD: Implement taskq_init_ent()

Previously taskq_init_ent() was an empty macro, while actual init
was done by taskq_dispatch_ent().  It could be slightly faster in
case taskq never enqueued. But without it taskq_empty_ent() relied
on the structure being zeroed by somebody else, that is not good.

As a side effect this allows the same task to be queued several
times, that is normal on FreeBSD, that may or may not get useful
here also one day.

Reviewed-by: Brian Atkinson <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by:	Alexander Motin <[email protected]>
Sponsored by:	iXsystems, Inc.
Closes #15455 

1 files changed, 18 insertions, 12 deletions

diff --git a/module/os/freebsd/spl/spl_taskq.c b/module/os/freebsd/spl/spl_taskq.c
index 6912b220a..cc276e568 100644
--- a/module/os/freebsd/spl/spl_taskq.c
+++ b/module/os/freebsd/spl/spl_taskq.c
@@ -480,22 +480,34 @@ void
 taskq_dispatch_ent(taskq_t *tq, task_func_t func, void *arg, uint32_t flags,
     taskq_ent_t *task)
 {
-	int prio;
-
 	/*
 	 * If TQ_FRONT is given, we want higher priority for this task, so it
 	 * can go at the front of the queue.
 	 */
-	prio = !!(flags & TQ_FRONT);
-	task->tqent_id = 0;
+	task->tqent_task.ta_priority = !!(flags & TQ_FRONT);
 	task->tqent_func = func;
 	task->tqent_arg = arg;
-
-	TASK_INIT(&task->tqent_task, prio, taskq_run_ent, task);
 	taskqueue_enqueue(tq->tq_queue, &task->tqent_task);
 }
 
 void
+taskq_init_ent(taskq_ent_t *task)
+{
+	TASK_INIT(&task->tqent_task, 0, taskq_run_ent, task);
+	task->tqent_func = NULL;
+	task->tqent_arg = NULL;
+	task->tqent_id = 0;
+	task->tqent_type = NORMAL_TASK;
+	task->tqent_rc = 0;
+}
+
+int
+taskq_empty_ent(taskq_ent_t *task)
+{
+	return (task->tqent_task.ta_pending == 0);
+}
+
+void
 taskq_wait(taskq_t *tq)
 {
 	taskqueue_quiesce(tq->tq_queue);
@@ -521,9 +533,3 @@ taskq_wait_outstanding(taskq_t *tq, taskqid_t id __unused)
 {
 	taskqueue_drain_all(tq->tq_queue);
 }
-
-int
-taskq_empty_ent(taskq_ent_t *t)
-{
-	return (t->tqent_task.ta_pending == 0);
-}