M sys/kern/subr_taskqueue.c
@@ -108,6 +108,7 @@ TQ_UNLOCK(struct taskqueue *tq)
 static __inline void
 TQ_SLEEP(struct taskqueue *tq, void *ident, const char *wmesg)
 {
+	kprintf("[ALY/DEBUG] %s@cpu#%d: tq=%p, ident=%p ...\n", __func__, mycpuid, tq, ident);
 	ssleep(ident, &tq->tq_lock, 0, wmesg, 0);
 }
 
@@ -613,10 +614,13 @@ taskqueue_thread_loop(void *arg)
 
 	tqp = arg;
 	tq = *tqp;
+	kprintf("[ALY/DEBUG] %s@cpu#%d: starting tq=%p ...\n", __func__, mycpuid, tq);
 	TQ_LOCK(tq);
 	while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) {
+		kprintf("[ALY/DEBUG] %s@cpu#%d: running tq=%p ...\n", __func__, mycpuid, tq);
 		taskqueue_run(tq, 1);
 		TQ_SLEEP(tq, tq, "tqthr");
+		kprintf("[ALY/DEBUG] %s@cpu#%d: tq=%p woken up\n", __func__, mycpuid, tq);
 	}
 
 	/* rendezvous with thread that asked us to terminate */
@@ -637,6 +641,7 @@ taskqueue_thread_enqueue(void *context)
 
 	/* Unlock spinlock before wakeup_one() */
 	TQ_UNLOCK(tq);
+	kprintf("[ALY/DEBUG] %s@cpu#%d: waking up tq=%p ...\n", __func__, mycpuid, tq);
 	wakeup_one(tq);
 	TQ_LOCK(tq);
 }


$ sudo kldload ./if_wg.ko

[ALY/DEBUG] wg_module_init@cpu#0: created tq=0xfffff80065c97db8
[ALY/DEBUG] wg_module_init@cpu#0: created tq=0xfffff80065c97e10
[ALY/DEBUG] wg_module_init@cpu#0: created tq=0xfffff80065c97e68
[ALY/DEBUG] wg_module_init@cpu#0: created tq=0xfffff80065c97ec0
[ALY/DEBUG] taskqueue_thread_loop@cpu#0: starting tq=0xfffff80065c97db8 ...
[ALY/DEBUG] taskqueue_thread_loop@cpu#0: running tq=0xfffff80065c97db8 ...
[ALY/DEBUG] TQ_SLEEP@cpu#0: tq=0xfffff80065c97db8, ident=0xfffff80065c97db8 ...

$ ps -ax -O nwchan | grep wg_
    -1 fffff80065c97db8 ??  B0       0:00.01 (wg_taskq_cpu_0)
    -1 fffff80065c97e10 ??  B1       0:00.00 (wg_taskq_cpu_1)
    -1 fffff80065c97e68 ??  B2       0:00.00 (wg_taskq_cpu_2)
    -1 fffff80065c97ec0 ??  B3       0:00.00 (wg_taskq_cpu_3)

$ ps -ax -O wchan | grep wg_taskq
    -1 tqthr    ??  B0       0:00.01 (wg_taskq_cpu_0)
    -1 tqthr    ??  B1       0:00.00 (wg_taskq_cpu_1)
    -1 tqthr    ??  B2       0:00.00 (wg_taskq_cpu_2)
    -1 tqthr    ??  B3       0:00.00 (wg_taskq_cpu_3)

$ sudo kldunload if_wg

[ALY/DEBUG] TQ_SLEEP@cpu#0: tq=0xfffff80065c97db8, ident=0xfffff800463426f0 ...
[ALY/DEBUG] taskqueue_thread_loop@cpu#0: tq=0xfffff80065c97db8 woken up
[ALY/DEBUG] TQ_SLEEP@cpu#0: tq=0xfffff80065c97e10, ident=0xfffff800463426f8 ...
[ALY/DEBUG] taskqueue_thread_loop@cpu#1: tq=0xfffff80065c97e10 woken up
[ALY/DEBUG] TQ_SLEEP@cpu#0: tq=0xfffff80065c97e68, ident=0xfffff80046342700 ...
[ALY/DEBUG] taskqueue_thread_loop@cpu#2: tq=0xfffff80065c97e68 woken up
[ALY/DEBUG] TQ_SLEEP@cpu#0: tq=0xfffff80065c97ec0, ident=0xfffff80046342708 ...
[ALY/DEBUG] taskqueue_thread_loop@cpu#3: tq=0xfffff80065c97ec0 woken up