Revert 64b96f029c partially

This reverts commit 819edd83e3.

lib/dns/resolver.c

@@ -4382,8 +4382,8 @@ fctx_shutdown(fetchctx_t *fctx) {
 	 */
 	if (fctx->state != fetchstate_init) {
 		cevent = &fctx->control_event;
-		isc_task_send(fctx->res->buckets[fctx->bucketnum].task,
-			      &cevent);
+		isc_task_sendto(fctx->res->buckets[fctx->bucketnum].task,
+			        &cevent, fctx->bucketnum);
 	}
 }
 
@@ -9925,7 +9925,7 @@ dns_resolver_create(dns_view_t *view,
 		if (result != ISC_R_SUCCESS)
 			goto cleanup_buckets;
 		res->buckets[i].task = NULL;
-		result = isc_task_create(taskmgr, 0, &res->buckets[i].task);
+		result = isc_task_create_bound(taskmgr, 0, &res->buckets[i].task, i);
 		if (result != ISC_R_SUCCESS) {
 			DESTROYLOCK(&res->buckets[i].lock);
 			goto cleanup_buckets;
@@ -10563,7 +10563,7 @@ dns_resolver_createfetch(dns_resolver_t *res, const dns_name_t *name,
 				       DNS_EVENT_FETCHCONTROL,
 				       fctx_start, fctx, NULL,
 				       NULL, NULL);
-			isc_task_send(res->buckets[bucketnum].task, &event);
+			isc_task_sendto(res->buckets[bucketnum].task, &event, bucketnum);
 		} else {
 			/*
 			 * We don't care about the result of fctx_unlink()

lib/isc/include/isc/task.h

@@ -136,6 +136,10 @@ struct isc_task {
 isc_result_t
 isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
 		isc_task_t **taskp);
+
+isc_result_t
+isc_task_create_bound(isc_taskmgr_t *manager, unsigned int quantum,
+		      isc_task_t **taskp, int threadid);
 /*%<
  * Create a task.
  *

lib/isc/task.c

@@ -104,6 +104,7 @@ struct isc__task {
 	char				name[16];
 	void *				tag;
 	unsigned int			threadid;
+	bool				bound;
 	/* Locked by task manager lock. */
 	LINK(isc__task_t)		link;
 	LINK(isc__task_t)		ready_link;
@@ -243,7 +244,14 @@ task_finished(isc__task_t *task) {
 
 isc_result_t
 isc_task_create(isc_taskmgr_t *manager0, unsigned int quantum,
-		 isc_task_t **taskp)
+		isc_task_t **taskp)
+{
+	return (isc_task_create_bound(manager0, quantum, taskp, -1));
+}
+
+isc_result_t
+isc_task_create_bound(isc_taskmgr_t *manager0, unsigned int quantum,
+		      isc_task_t **taskp, int threadid)
 {
 	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
 	isc__task_t *task;
@@ -258,9 +266,15 @@ isc_task_create(isc_taskmgr_t *manager0, unsigned int quantum,
 		return (ISC_R_NOMEMORY);
 	XTRACE("isc_task_create");
 	task->manager = manager;
-	task->threadid = atomic_fetch_add_explicit(&manager->curq, 1,
-						   memory_order_relaxed)
-						   % manager->workers;
+	if (threadid == -1) {
+		task->bound = false;
+		task->threadid = atomic_fetch_add_explicit(&manager->curq, 1,
+							   memory_order_relaxed)
+							   % manager->workers;
+	} else {
+		task->bound = true;
+		task->threadid = threadid % manager->workers;
+	}
 	result = isc_mutex_init(&task->lock);
 	if (result != ISC_R_SUCCESS) {
 		isc_mem_put(manager->mctx, task, sizeof(*task));
@@ -494,7 +508,9 @@ isc_task_sendto(isc_task_t *task0, isc_event_t **eventp, int c) {
 	REQUIRE(VALID_TASK(task));
 	XTRACE("isc_task_send");
 
-	if (c < 0) {
+	if (task->bound) {
+		c = task->threadid;
+	} else if (c < 0) {
 		c = atomic_fetch_add_explicit(&task->manager->curq, 1,
 					      memory_order_relaxed);
 	}
@@ -544,7 +560,9 @@ isc_task_sendtoanddetach(isc_task_t **taskp, isc_event_t **eventp, int c) {
 	REQUIRE(VALID_TASK(task));
 	XTRACE("isc_task_sendanddetach");
 
-	if (c < 0) {
+	if (task->bound) {
+		c = task->threadid;
+	} else if (c < 0) {
 		c = atomic_fetch_add_explicit(&task->manager->curq, 1,
 					      memory_order_relaxed);
 	}