Index: share/man/man9/task_add.9
===================================================================
RCS file: /cvs/src/share/man/man9/task_add.9,v
retrieving revision 1.18
diff -u -p -r1.18 task_add.9
--- share/man/man9/task_add.9	16 Dec 2018 03:40:12 -0000	1.18
+++ share/man/man9/task_add.9	29 Mar 2019 04:26:01 -0000
@@ -81,9 +81,6 @@ argument:
 .Bl -tag -width xxx -offset indent
 .It Dv TASKQ_MPSAFE
 The threads servicing the taskq will be run without the kernel big lock.
-.It Dv TASKQ_CANTSLEEP
-The tasks run via the taskq cannot sleep.
-.El
 .Pp
 .Fn taskq_destroy
 causes the resources associated with a previously created taskq to be freed.
Index: sys/sys/task.h
===================================================================
RCS file: /cvs/src/sys/sys/task.h,v
retrieving revision 1.13
diff -u -p -r1.13 task.h
--- sys/sys/task.h	16 Dec 2018 03:36:02 -0000	1.13
+++ sys/sys/task.h	29 Mar 2019 04:26:01 -0000
@@ -35,7 +35,6 @@ struct task {
 TAILQ_HEAD(task_list, task);
 
 #define TASKQ_MPSAFE		(1 << 0)
-#define TASKQ_CANTSLEEP		(1 << 1)
 
 #define TASK_INITIALIZER(_f, _a)  {{ NULL, NULL }, (_f), (_a), 0 }
 
Index: sys/kern/kern_task.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_task.c,v
retrieving revision 1.23
diff -u -p -r1.23 kern_task.c
--- sys/kern/kern_task.c	16 Dec 2018 03:36:02 -0000	1.23
+++ sys/kern/kern_task.c	29 Mar 2019 04:26:01 -0000
@@ -59,9 +59,6 @@ struct taskq taskq_sys_mp = {
 	TAILQ_HEAD_INITIALIZER(taskq_sys_mp.tq_worklist)
 };
 
-typedef int (*sleepfn)(const volatile void *, struct mutex *, int,
-    const char *, int);
-
 struct taskq *const systq = &taskq_sys;
 struct taskq *const systqmp = &taskq_sys_mp;
 
@@ -70,7 +67,7 @@ void	taskq_create_thread(void *);
 void	taskq_barrier_task(void *);
 int	taskq_sleep(const volatile void *, struct mutex *, int,
 	    const char *, int);
-int	taskq_next_work(struct taskq *, struct task *, sleepfn);
+int	taskq_next_work(struct taskq *, struct task *);
 void	taskq_thread(void *);
 
 void
@@ -246,21 +243,7 @@ task_del(struct taskq *tq, struct task *
 }
 
 int
-taskq_sleep(const volatile void *ident, struct mutex *mtx, int priority,
-    const char *wmesg, int tmo)
-{
-	u_int *flags = &curproc->p_flag;
-	int rv;
-
-	atomic_clearbits_int(flags, P_CANTSLEEP);
-	rv = msleep(ident, mtx, priority, wmesg, tmo);
-	atomic_setbits_int(flags, P_CANTSLEEP);
-
-	return (tmo);
-}
-
-int
-taskq_next_work(struct taskq *tq, struct task *work, sleepfn tqsleep)
+taskq_next_work(struct taskq *tq, struct task *work)
 {
 	struct task *next;
 
@@ -271,7 +254,7 @@ taskq_next_work(struct taskq *tq, struct
 			return (0);
 		}
 
-		tqsleep(tq, &tq->tq_mtx, PWAIT, "bored", 0);
+		msleep(tq, &tq->tq_mtx, PWAIT, "bored", 0);
 	}
 
 	TAILQ_REMOVE(&tq->tq_worklist, next, t_entry);
@@ -291,7 +274,6 @@ taskq_next_work(struct taskq *tq, struct
 void
 taskq_thread(void *xtq)
 {
-	sleepfn tqsleep = msleep;
 	struct taskq *tq = xtq;
 	struct task work;
 	int last;
@@ -299,12 +281,7 @@ taskq_thread(void *xtq)
 	if (ISSET(tq->tq_flags, TASKQ_MPSAFE))
 		KERNEL_UNLOCK();
 
-	if (ISSET(tq->tq_flags, TASKQ_CANTSLEEP)) {
-		tqsleep = taskq_sleep;
-		atomic_setbits_int(&curproc->p_flag, P_CANTSLEEP);
-	}
-
-	while (taskq_next_work(tq, &work, tqsleep)) {
+	while (taskq_next_work(tq, &work)) {
 		(*work.t_func)(work.t_arg);
 		sched_pause(yield);
 	}
@@ -312,9 +289,6 @@ taskq_thread(void *xtq)
 	mtx_enter(&tq->tq_mtx);
 	last = (--tq->tq_running == 0);
 	mtx_leave(&tq->tq_mtx);
-
-	if (ISSET(tq->tq_flags, TASKQ_CANTSLEEP))
-		atomic_clearbits_int(&curproc->p_flag, P_CANTSLEEP);
 
 	if (ISSET(tq->tq_flags, TASKQ_MPSAFE))
 		KERNEL_LOCK();
Index: sys/kern/kern_synch.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_synch.c,v
retrieving revision 1.147
diff -u -p -r1.147 kern_synch.c
--- sys/kern/kern_synch.c	23 Jan 2019 21:53:42 -0000	1.147
+++ sys/kern/kern_synch.c	29 Mar 2019 04:26:01 -0000
@@ -273,8 +273,6 @@ sleep_setup(struct sleep_state *sls, con
 	struct proc *p = curproc;
 
 #ifdef DIAGNOSTIC
-	if (p->p_flag & P_CANTSLEEP)
-		panic("sleep: %s failed insomnia", p->p_p->ps_comm);
 	if (ident == NULL)
 		panic("tsleep: no ident");
 	if (p->p_stat != SONPROC)