we cannot run ved_tasks in a parent's thread

... because of T_FINAL.

Because the parent's thread (except for the root) will terminate
eventually, this is also all good, except for the case that we spend all
available threads on T_FINAL.

Leave the hard problems for later, *sigh*

src/vdp_pesi.c

@@ -822,8 +822,7 @@ ved_task(struct worker *wrk, void *priv)
 	enum req_fsm_nxt s;
 
 	CHECK_OBJ_NOTNULL(wrk, WORKER_MAGIC);
-	req = *((struct req **)priv);
-	CHECK_OBJ_NOTNULL(req, REQ_MAGIC);
+	CAST_OBJ_NOTNULL(req, priv, REQ_MAGIC);
 	VSLdbgv(req, "ved_task: req=%p", req);
 
 	assert(req->esi_level > 0);
@@ -840,7 +839,6 @@ ved_task(struct worker *wrk, void *priv)
 	CHECK_OBJ_NOTNULL(node, NODE_MAGIC);
 	CHECK_OBJ_NOTNULL(pesi_tree->tree, BYTES_TREE_MAGIC);
 
-	WS_Release(wrk->aws, sizeof(req));
 	THR_SetRequest(req);
 	VSLb_ts_req(req, "Start", W_TIM_real(wrk));
 
@@ -944,7 +942,6 @@ vped_include(struct req *preq, const char *src, const char *host,
 	struct req *req;
 	struct bytes_tree *tree;
 	struct pesi *pesi2;
-	int parallel = 1;
 
 	VSLdbg(preq, "ved_include: enter");
 	CHECK_OBJ_NOTNULL(preq, REQ_MAGIC);
@@ -1058,23 +1055,26 @@ vped_include(struct req *preq, const char *src, const char *host,
 	assert(node->type == T_NEXUS);
 	node->req = req;
 
+	// XXX still needed?
 	preq->wrk->task.func = NULL;
 	if (wrk->aws->r != NULL)
 		WS_ReleaseP(wrk->aws, wrk->aws->r);
 	VSLdbgv(preq, "ved_include: attempt new thread req=%p", req);
-	if (Pool_Task_Arg(wrk, TASK_QUEUE_REQ, ved_task, &req, sizeof(req)))
-		VSLdbgv(preq, "Parallel ESI request started on a new thread "
-			"xid=%d", VXID(req->vsl->wid));
-	else {
-		parallel = 0;
-		VSLb(preq->vsl, SLT_VCL_Error, "No idle threads available for "
-		     "parallel ESI request xid=%d, continued in the same "
-		     "thread", VXID(req->vsl->wid));
-		ved_task(wrk, &req);
-		VSLdbgv(preq, "ved_include: done in same thread req=%p", req);
-	}
-	VSLdbgv(preq, "ved_include: exit parallel=%d", parallel);
-	return (parallel);
+
+	/* XXX because of T_FINAL blocking in the subreq thread,
+	 * these threads *have* to run.
+	 *
+	 * ordering should ensure that we run top->bottom left-right in the ESI
+	 * tree, so delivery should be able to let T_FINAL threads run, and
+	 * anything but T_FINAL should terminate eventually, but if we spend all
+	 * available threads on T_FINAL, we're doomed.
+	 *
+	 * -- find a way to reserve or check for T_FINAL
+	 */
+	req->task.func = ved_task;
+	req->task.priv = req;
+	AZ(Pool_Task(wrk->pool, &req->task, TASK_QUEUE_RUSH));
+	return (1);
 }
 
 /*--------------------------------------------------------------------*/
@@ -2233,18 +2233,7 @@ vdp_pesi_bytes(struct req *req, enum vdp_action act, void **priv,
 				VSLdbgv(req, "ved_vdp: vped_include()=%d",
 					parallel);
 				/* XXX error if parallel < 0 */
-#if 0
-				// slink: shouldn't ved_task work irrespective
-				// of being in a different thread?
-				if (!parallel) {
-					VSLdbgv(req,
-						"ved_vdp: pushing VDP tree=%p",
-						tree);
-					XXXAZ(push_vdps_esi(req));
-				}
-#else
-				AN(parallel);
-#endif
+				assert(parallel == 1);
 				Debug("INCL [%s][%s] END\n", q, pecx->p);
 				pecx->p = r + 1;
 				break;
@@ -2322,7 +2311,8 @@ vdp_pesi_bytes(struct req *req, enum vdp_action act, void **priv,
 #else
 				(void)(Lck_CondWait(&tree->cond,
 						    &tree->tree_lock,
-						    VTIM_real() + 0.1));
+						    VTIM_real() + 2));
+				AZ(errno);
 #endif
 				bytes_unpend(req, tree);
 			}