Merge commit 'refs/top-bases/linux-have-zvol' into linux-have-zvol

5 files changed, 228 insertions, 99 deletions

diff --git a/cmd/ztest/ztest.c b/cmd/ztest/ztest.c
index 4da772d3a..ae21ae0a5 100644
--- a/cmd/ztest/ztest.c
+++ b/cmd/ztest/ztest.c
@@ -141,6 +141,7 @@ typedef struct ztest_args {
 	objset_t	*za_os;
 	zilog_t		*za_zilog;
 	kthread_t	*za_thread;
+	kt_did_t	za_threadid;
 	uint64_t	za_instance;
 	uint64_t	za_random;
 	uint64_t	za_diroff;
@@ -3820,6 +3821,8 @@ ztest_resume_thread(void *arg)
 		(void) poll(NULL, 0, 1000);
 		ztest_resume(spa);
 	}
+
+	thread_exit();
 	return (NULL);
 }
 
@@ -3884,6 +3887,7 @@ ztest_thread(void *arg)
 			break;
 	}
 
+	thread_exit();
 	return (NULL);
 }
 
@@ -3899,6 +3903,7 @@ ztest_run(char *pool)
 	spa_t *spa;
 	char name[100];
 	kthread_t *resume_thread;
+	kt_did_t resume_id;
 
 	ztest_exiting = B_FALSE;
 
@@ -3977,8 +3982,9 @@ ztest_run(char *pool)
 	/*
 	 * Create a thread to periodically resume suspended I/O.
 	 */
-	resume_thread = thread_create(NULL, 0, ztest_resume_thread, spa,
-				      THR_BOUND, NULL, 0, 0);
+	VERIFY3P((resume_thread = thread_create(NULL, 0, ztest_resume_thread,
+	         spa, THR_BOUND, NULL, 0, 0)), !=, NULL);
+	resume_id = resume_thread->t_tid;
 
 	/*
 	 * Verify that we can safely inquire about about any object,
@@ -4054,12 +4060,13 @@ ztest_run(char *pool)
 			za[d].za_zilog = zil_open(za[d].za_os, NULL);
 		}
 
-		za[t].za_thread = thread_create(NULL, 0, ztest_thread, &za[t],
-						THR_BOUND, NULL, 0, 0);
+		VERIFY3P((za[t].za_thread = thread_create(NULL, 0, ztest_thread,
+		         &za[t], THR_BOUND, NULL, 0, 0)), !=, NULL);
+		za[t].za_threadid = za[t].za_thread->t_tid;
 	}
 
 	while (--t >= 0) {
-		VERIFY(thr_join(za[t].za_thread, NULL, NULL) == 0);
+		VERIFY(thread_join(za[t].za_threadid, NULL, NULL) == 0);
 		if (t < zopt_datasets) {
 			zil_close(za[t].za_zilog);
 			dmu_objset_close(za[t].za_os);
@@ -4098,7 +4105,7 @@ ztest_run(char *pool)
 
 	/* Kill the resume thread */
 	ztest_exiting = B_TRUE;
-	VERIFY(thr_join(resume_thread, NULL, NULL) == 0);
+	VERIFY(thread_join(resume_id, NULL, NULL) == 0);
 	ztest_resume(spa);
 
 	/*
diff --git a/lib/libzpool/include/sys/zfs_context.h b/lib/libzpool/include/sys/zfs_context.h
index cd8f41073..7c3c5e0d5 100644
--- a/lib/libzpool/include/sys/zfs_context.h
+++ b/lib/libzpool/include/sys/zfs_context.h
@@ -198,24 +198,34 @@ _NOTE(CONSTCOND) } while (0)
 /*
  * Threads
  */
-#define	tsd_get(key)		pthread_getspecific(key)
-#define	tsd_set(key, val)	pthread_setspecific(key, val)
+#define THR_BOUND		0x00000001
+#define TS_RUN			0x00000002
 
 typedef void (*thread_func_t)(void *);
+typedef pthread_t kt_did_t;
+
 typedef struct kthread {
         list_node_t	t_node;
-	pthread_t	t_id;
+	kt_did_t	t_tid;
 	pthread_attr_t	t_attr;
 } kthread_t;
 
-#define	curthread		zk_curthread()
-#define thread_create(stk, stksize, func, arg, len, pp, state, pri) \
-				zk_thread_create((thread_func_t)func, arg)
-#define thr_join(kt, v1, v2)	pthread_join(kt->t_id, v2)
-
-extern kthread_t *zk_curthread(void);
-extern kthread_t *zk_thread_create(thread_func_t func, void *arg);
-extern void thread_exit(void);
+#define	tsd_get(key)		pthread_getspecific(key)
+#define	tsd_set(key, val)	pthread_setspecific(key, val)
+#define	curthread		zk_thread_current()
+#define thread_exit		zk_thread_exit
+#define thread_create(stk, stksize, func, arg, len, pp, state, pri)	\
+	zk_thread_create(stk, stksize, (thread_func_t)func, arg,	\
+			 len, NULL, state, pri)
+#define thread_join(tid, dtid, status)					\
+	zk_thread_join(tid, dtid, status)
+
+extern kthread_t *zk_thread_current(void);
+extern void zk_thread_exit(void);
+extern kthread_t *zk_thread_create(caddr_t stk, size_t  stksize,
+	thread_func_t func, void *arg, size_t len,
+	void *pp, int state, pri_t pri);
+extern int zk_thread_join(kt_did_t tid, kthread_t *dtid, void **status);
 
 #define	issig(why)	(FALSE)
 #define	ISSIG(thr, why)	(FALSE)
@@ -224,6 +234,8 @@ extern void thread_exit(void);
  * Mutexes
  */
 #define MTX_MAGIC 0x9522f51362a6e326ull
+#define MTX_INIT  (void *)NULL
+#define MTX_DEST  (void *)-1UL
 typedef struct kmutex {
 	void		*m_owner;
 	uint64_t	m_magic;
@@ -244,6 +256,8 @@ extern void *mutex_owner(kmutex_t *mp);
  * RW locks
  */
 #define RW_MAGIC 0x4d31fb123648e78aull
+#define RW_INIT  (void *)NULL
+#define RW_DEST  (void *)-1UL
 typedef struct krwlock {
 	void			*rw_owner;
 	void			*rw_wr_owner;
@@ -345,6 +359,7 @@ extern void	taskq_destroy(taskq_t *);
 extern void	taskq_wait(taskq_t *);
 extern int	taskq_member(taskq_t *, void *);
 extern void	system_taskq_init(void);
+extern void	system_taskq_fini(void);
 
 #define	XVA_MAPSIZE	3
 #define	XVA_MAGIC	0x78766174
diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c
index 6b7c3e9d1..4a962b8e2 100644
--- a/lib/libzpool/kernel.c
+++ b/lib/libzpool/kernel.c
@@ -30,6 +30,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <zlib.h>
+#include <sys/signal.h>
 #include <sys/spa.h>
 #include <sys/stat.h>
 #include <sys/processor.h>
@@ -56,64 +57,157 @@ struct utsname utsname = {
  * =========================================================================
  */
 
-kmutex_t kthread_lock;
+/* NOTE: Tracking each tid on a list and using it for curthread lookups
+ *       is slow at best but it provides an easy way to provide a kthread
+ *       style API on top of pthreads.  For now we just want ztest to work
+ *       to validate correctness.  Performance is not much of an issue
+ *       since that is what the in-kernel version is for.  That said
+ *       reworking this to track the kthread_t structure as thread
+ *       specific data would be probably the best way to speed this up.
+ */
+
+pthread_cond_t kthread_cond = PTHREAD_COND_INITIALIZER;
+pthread_mutex_t kthread_lock = PTHREAD_MUTEX_INITIALIZER;
 list_t kthread_list;
 
-kthread_t *
-zk_curthread(void)
+static int
+thread_count(void)
 {
 	kthread_t *kt;
-	pthread_t tid;
+	int count = 0;
+
+	for (kt = list_head(&kthread_list); kt != NULL;
+	     kt = list_next(&kthread_list, kt))
+		count++;
+
+	return count;
+}
+
+static void
+thread_init(void)
+{
+	kthread_t *kt;
+
+	/* Initialize list for tracking kthreads */
+	list_create(&kthread_list, sizeof (kthread_t),
+		    offsetof(kthread_t, t_node));
 
-	tid = pthread_self();
-	mutex_enter(&kthread_lock);
-        for (kt = list_head(&kthread_list); kt != NULL;
-	     kt = list_next(&kthread_list, kt)) {
+	/* Create entry for primary kthread */
+	kt = umem_zalloc(sizeof(kthread_t), UMEM_NOFAIL);
+	list_link_init(&kt->t_node);
+	VERIFY3U(kt->t_tid = pthread_self(), !=, 0);
+        VERIFY3S(pthread_attr_init(&kt->t_attr), ==, 0);
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
+	list_insert_head(&kthread_list, kt);
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
+}
+
+static void
+thread_fini(void)
+{
+	kthread_t *kt;
+	struct timespec ts = { 0 };
+	int count;
+
+	/* Wait for all threads to exit via thread_exit() */
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
+	while ((count = thread_count()) > 1) {
+		printf("Waiting for %d\n", count);
+		clock_gettime(CLOCK_REALTIME, &ts);
+		ts.tv_sec += 1;
+		pthread_cond_timedwait(&kthread_cond, &kthread_lock, &ts);
+	}
+
+	ASSERT3S(thread_count(), ==, 1);
+	kt = list_head(&kthread_list);
+	list_remove(&kthread_list, kt);
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
+
+	VERIFY(pthread_attr_destroy(&kt->t_attr) == 0);
+	umem_free(kt, sizeof(kthread_t));
 
-		if (kt->t_id == tid) {
-			mutex_exit(&kthread_lock);
-			return kt;
+	/* Cleanup list for tracking kthreads */
+	list_destroy(&kthread_list);
+}
+
+kthread_t *
+zk_thread_current(void)
+{
+	kt_did_t tid = pthread_self();
+	kthread_t *kt;
+	int count = 1;
+
+	/*
+	 * Because a newly created thread may call zk_thread_current()
+	 * before the thread parent has had time to add the thread's tid
+	 * to our lookup list.  We will loop as long as there are tid
+	 * which have not yet been set which must be one of ours.
+	 * Yes it's a hack, at some point we can just use native pthreads.
+	 */
+	while (count > 0) {
+		count = 0;
+		VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
+		for (kt = list_head(&kthread_list); kt != NULL;
+		     kt = list_next(&kthread_list, kt)) {
+
+			if (kt->t_tid == tid) {
+				VERIFY3S(pthread_mutex_unlock(
+				         &kthread_lock), ==, 0);
+				return kt;
+			}
+
+			if (kt->t_tid == (kt_did_t)-1)
+				count++;
 		}
+		VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
 	}
-	mutex_exit(&kthread_lock);
 
+	/* Unreachable */
+	ASSERT(0);
 	return NULL;
 }
 
 kthread_t *
-zk_thread_create(thread_func_t func, void *arg)
+zk_thread_create(caddr_t stk, size_t  stksize, thread_func_t func, void *arg,
+	      size_t len, void *pp, int state, pri_t pri)
 {
 	kthread_t *kt;
 
 	kt = umem_zalloc(sizeof(kthread_t), UMEM_NOFAIL);
-
+	kt->t_tid = (kt_did_t)-1;
+	list_link_init(&kt->t_node);
 	VERIFY(pthread_attr_init(&kt->t_attr) == 0);
-	VERIFY(pthread_attr_setdetachstate(&kt->t_attr,
-					   PTHREAD_CREATE_DETACHED) == 0);
-	VERIFY(pthread_create(&kt->t_id, &kt->t_attr,
-			      (void *(*)(void *))func, arg) == 0);
 
-	mutex_enter(&kthread_lock);
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
 	list_insert_head(&kthread_list, kt);
-	mutex_exit(&kthread_lock);
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
+
+	VERIFY(pthread_create(&kt->t_tid, &kt->t_attr,
+			      (void *(*)(void *))func, arg) == 0);
 
 	return kt;
 }
 
+int
+zk_thread_join(kt_did_t tid, kthread_t *dtid, void **status)
+{
+	return pthread_join(tid, status);
+}
+
 void
-thread_exit(void)
+zk_thread_exit(void)
 {
 	kthread_t *kt;
 
-	VERIFY((kt = curthread) != NULL);
-
-	mutex_enter(&kthread_lock);
+	VERIFY3P(kt = curthread, !=, NULL);
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
 	list_remove(&kthread_list, kt);
-	mutex_exit(&kthread_lock);
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
 
 	VERIFY(pthread_attr_destroy(&kt->t_attr) == 0);
 	umem_free(kt, sizeof(kthread_t));
 
+	pthread_cond_broadcast(&kthread_cond);
 	pthread_exit(NULL);
 }
 
@@ -148,14 +242,14 @@ kstat_delete(kstat_t *ksp)
 void
 mutex_init(kmutex_t *mp, char *name, int type, void *cookie)
 {
-	ASSERT(type == MUTEX_DEFAULT);
-	ASSERT(cookie == NULL);
+	ASSERT3S(type, ==, MUTEX_DEFAULT);
+	ASSERT3P(cookie, ==, NULL);
 
 #ifdef IM_FEELING_LUCKY
-	ASSERT(mp->m_magic != MTX_MAGIC);
+	ASSERT3U(mp->m_magic, !=, MTX_MAGIC);
 #endif
 
-	mp->m_owner = NULL;
+	mp->m_owner = MTX_INIT;
 	mp->m_magic = MTX_MAGIC;
 	VERIFY3S(pthread_mutex_init(&mp->m_lock, NULL), ==, 0);
 }
@@ -163,31 +257,31 @@ mutex_init(kmutex_t *mp, char *name, int type, void *cookie)
 void
 mutex_destroy(kmutex_t *mp)
 {
-	ASSERT(mp->m_magic == MTX_MAGIC);
-	ASSERT(mp->m_owner == NULL);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mp->m_owner, ==, MTX_INIT);
 	VERIFY3S(pthread_mutex_destroy(&(mp)->m_lock), ==, 0);
-	mp->m_owner = (void *)-1UL;
+	mp->m_owner = MTX_DEST;
 	mp->m_magic = 0;
 }
 
 void
 mutex_enter(kmutex_t *mp)
 {
-	ASSERT(mp->m_magic == MTX_MAGIC);
-	ASSERT(mp->m_owner != (void *)-1UL);
-	ASSERT(mp->m_owner != curthread);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mp->m_owner, !=, MTX_DEST);
+	ASSERT3P(mp->m_owner, !=, curthread);
 	VERIFY3S(pthread_mutex_lock(&mp->m_lock), ==, 0);
-	ASSERT(mp->m_owner == NULL);
+	ASSERT3P(mp->m_owner, ==, MTX_INIT);
 	mp->m_owner = curthread;
 }
 
 int
 mutex_tryenter(kmutex_t *mp)
 {
-	ASSERT(mp->m_magic == MTX_MAGIC);
-	ASSERT(mp->m_owner != (void *)-1UL);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mp->m_owner, !=, MTX_DEST);
 	if (0 == pthread_mutex_trylock(&mp->m_lock)) {
-		ASSERT(mp->m_owner == NULL);
+		ASSERT3P(mp->m_owner, ==, MTX_INIT);
 		mp->m_owner = curthread;
 		return (1);
 	} else {
@@ -198,16 +292,16 @@ mutex_tryenter(kmutex_t *mp)
 void
 mutex_exit(kmutex_t *mp)
 {
-	ASSERT(mp->m_magic == MTX_MAGIC);
-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mutex_owner(mp), ==, curthread);
+	mp->m_owner = MTX_INIT;
 	VERIFY3S(pthread_mutex_unlock(&mp->m_lock), ==, 0);
 }
 
 void *
 mutex_owner(kmutex_t *mp)
 {
-	ASSERT(mp->m_magic == MTX_MAGIC);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
 	return (mp->m_owner);
 }
 
@@ -220,16 +314,16 @@ mutex_owner(kmutex_t *mp)
 void
 rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
 {
-	ASSERT(type == RW_DEFAULT);
-	ASSERT(arg == NULL);
+	ASSERT3S(type, ==, RW_DEFAULT);
+	ASSERT3P(arg, ==, NULL);
 
 #ifdef IM_FEELING_LUCKY
-	ASSERT(rwlp->rw_magic != RW_MAGIC);
+	ASSERT3U(rwlp->rw_magic, !=, RW_MAGIC);
 #endif
 
 	VERIFY3S(pthread_rwlock_init(&rwlp->rw_lock, NULL), ==, 0);
-	rwlp->rw_owner = NULL;
-	rwlp->rw_wr_owner = NULL;
+	rwlp->rw_owner = RW_INIT;
+	rwlp->rw_wr_owner = RW_INIT;
 	rwlp->rw_readers = 0;
 	rwlp->rw_magic = RW_MAGIC;
 }
@@ -237,7 +331,7 @@ rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
 void
 rw_destroy(krwlock_t *rwlp)
 {
-	ASSERT(rwlp->rw_magic == RW_MAGIC);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
 
 	VERIFY3S(pthread_rwlock_destroy(&rwlp->rw_lock), ==, 0);
 	rwlp->rw_magic = 0;
@@ -246,18 +340,18 @@ rw_destroy(krwlock_t *rwlp)
 void
 rw_enter(krwlock_t *rwlp, krw_t rw)
 {
-	ASSERT(rwlp->rw_magic == RW_MAGIC);
-	ASSERT(rwlp->rw_owner != curthread);
-	ASSERT(rwlp->rw_wr_owner != curthread);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
+	ASSERT3P(rwlp->rw_owner, !=, curthread);
+	ASSERT3P(rwlp->rw_wr_owner, !=, curthread);
 
 	if (rw == RW_READER) {
 		VERIFY3S(pthread_rwlock_rdlock(&rwlp->rw_lock), ==, 0);
-		ASSERT(rwlp->rw_wr_owner == NULL);
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
 
 		atomic_inc_uint(&rwlp->rw_readers);
 	} else {
 		VERIFY3S(pthread_rwlock_wrlock(&rwlp->rw_lock), ==, 0);
-		ASSERT(rwlp->rw_wr_owner == NULL);
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
 		ASSERT3U(rwlp->rw_readers, ==, 0);
 
 		rwlp->rw_wr_owner = curthread;
@@ -269,15 +363,15 @@ rw_enter(krwlock_t *rwlp, krw_t rw)
 void
 rw_exit(krwlock_t *rwlp)
 {
-	ASSERT(rwlp->rw_magic == RW_MAGIC);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
 	ASSERT(RW_LOCK_HELD(rwlp));
 
 	if (RW_READ_HELD(rwlp))
 		atomic_dec_uint(&rwlp->rw_readers);
 	else
-		rwlp->rw_wr_owner = NULL;
+		rwlp->rw_wr_owner = RW_INIT;
 
-	rwlp->rw_owner = NULL;
+	rwlp->rw_owner = RW_INIT;
 	VERIFY3S(pthread_rwlock_unlock(&rwlp->rw_lock), ==, 0);
 }
 
@@ -286,7 +380,7 @@ rw_tryenter(krwlock_t *rwlp, krw_t rw)
 {
 	int rv;
 
-	ASSERT(rwlp->rw_magic == RW_MAGIC);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
 
 	if (rw == RW_READER)
 		rv = pthread_rwlock_tryrdlock(&rwlp->rw_lock);
@@ -294,7 +388,7 @@ rw_tryenter(krwlock_t *rwlp, krw_t rw)
 		rv = pthread_rwlock_trywrlock(&rwlp->rw_lock);
 
 	if (rv == 0) {
-		ASSERT(rwlp->rw_wr_owner == NULL);
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
 
 		if (rw == RW_READER)
 			atomic_inc_uint(&rwlp->rw_readers);
@@ -316,7 +410,7 @@ rw_tryenter(krwlock_t *rwlp, krw_t rw)
 int
 rw_tryupgrade(krwlock_t *rwlp)
 {
-	ASSERT(rwlp->rw_magic == RW_MAGIC);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
 
 	return (0);
 }
@@ -330,10 +424,10 @@ rw_tryupgrade(krwlock_t *rwlp)
 void
 cv_init(kcondvar_t *cv, char *name, int type, void *arg)
 {
-	ASSERT(type == CV_DEFAULT);
+	ASSERT3S(type, ==, CV_DEFAULT);
 
 #ifdef IM_FEELING_LUCKY
-	ASSERT(cv->cv_magic != CV_MAGIC);
+	ASSERT3U(cv->cv_magic, !=, CV_MAGIC);
 #endif
 
 	cv->cv_magic = CV_MAGIC;
@@ -344,7 +438,7 @@ cv_init(kcondvar_t *cv, char *name, int type, void *arg)
 void
 cv_destroy(kcondvar_t *cv)
 {
-	ASSERT(cv->cv_magic == CV_MAGIC);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
 	VERIFY3S(pthread_cond_destroy(&cv->cv), ==, 0);
 	cv->cv_magic = 0;
 }
@@ -352,9 +446,9 @@ cv_destroy(kcondvar_t *cv)
 void
 cv_wait(kcondvar_t *cv, kmutex_t *mp)
 {
-	ASSERT(cv->cv_magic == CV_MAGIC);
-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
+	ASSERT3P(mutex_owner(mp), ==, curthread);
+	mp->m_owner = MTX_INIT;
 	int ret = pthread_cond_wait(&cv->cv, &mp->m_lock);
 	if (ret != 0)
 		VERIFY3S(ret, ==, EINTR);
@@ -369,7 +463,7 @@ cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
 	timestruc_t ts;
 	clock_t delta;
 
-	ASSERT(cv->cv_magic == CV_MAGIC);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
 
 top:
 	delta = abstime - lbolt;
@@ -385,8 +479,8 @@ top:
 		ts.tv_nsec -= NANOSEC;
 	}
 
-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
+	ASSERT3P(mutex_owner(mp), ==, curthread);
+	mp->m_owner = MTX_INIT;
 	error = pthread_cond_timedwait(&cv->cv, &mp->m_lock, &ts);
 	mp->m_owner = curthread;
 
@@ -404,14 +498,14 @@ top:
 void
 cv_signal(kcondvar_t *cv)
 {
-	ASSERT(cv->cv_magic == CV_MAGIC);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
 	VERIFY3S(pthread_cond_signal(&cv->cv), ==, 0);
 }
 
 void
 cv_broadcast(kcondvar_t *cv)
 {
-	ASSERT(cv->cv_magic == CV_MAGIC);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
 	VERIFY3S(pthread_cond_broadcast(&cv->cv), ==, 0);
 }
 
@@ -895,12 +989,8 @@ kernel_init(int mode)
 	VERIFY((random_fd = open("/dev/random", O_RDONLY)) != -1);
 	VERIFY((urandom_fd = open("/dev/urandom", O_RDONLY)) != -1);
 
-	mutex_init(&kthread_lock, NULL, MUTEX_DEFAULT, NULL);
-	list_create(&kthread_list, sizeof (kthread_t),
-		    offsetof(kthread_t, t_node));
-
+	thread_init();
 	system_taskq_init();
-
 	spa_init(mode);
 }
 
@@ -908,9 +998,8 @@ void
 kernel_fini(void)
 {
 	spa_fini();
-
-	list_destroy(&kthread_list);
-	mutex_destroy(&kthread_lock);
+	system_taskq_fini();
+	thread_fini();
 
 	close(random_fd);
 	close(urandom_fd);
diff --git a/lib/libzpool/taskq.c b/lib/libzpool/taskq.c
index 40dfb6789..42e2dd3f4 100644
--- a/lib/libzpool/taskq.c
+++ b/lib/libzpool/taskq.c
@@ -43,6 +43,7 @@ struct taskq {
 	kcondvar_t	tq_dispatch_cv;
 	kcondvar_t	tq_wait_cv;
 	kthread_t	**tq_threadlist;
+	kt_did_t	*tq_idlist;
 	int		tq_flags;
 	int		tq_active;
 	int		tq_nthreads;
@@ -163,6 +164,7 @@ taskq_thread(void *arg)
 	tq->tq_nthreads--;
 	cv_broadcast(&tq->tq_wait_cv);
 	mutex_exit(&tq->tq_lock);
+	thread_exit();
 	return (NULL);
 }
 
@@ -198,7 +200,10 @@ taskq_create(const char *name, int nthreads, pri_t pri,
 	tq->tq_maxalloc = maxalloc;
 	tq->tq_task.task_next = &tq->tq_task;
 	tq->tq_task.task_prev = &tq->tq_task;
-	tq->tq_threadlist = kmem_alloc(nthreads*sizeof(kthread_t *), KM_SLEEP);
+	VERIFY3P((tq->tq_threadlist = kmem_alloc(tq->tq_nthreads *
+	         sizeof(kthread_t *), KM_SLEEP)), !=, NULL);
+	VERIFY3P((tq->tq_idlist = kmem_alloc(tq->tq_nthreads *
+	         sizeof(kt_did_t), KM_SLEEP)), !=, NULL);
 
 	if (flags & TASKQ_PREPOPULATE) {
 		mutex_enter(&tq->tq_lock);
@@ -207,9 +212,11 @@ taskq_create(const char *name, int nthreads, pri_t pri,
 		mutex_exit(&tq->tq_lock);
 	}
 
-	for (t = 0; t < nthreads; t++)
+	for (t = 0; t < tq->tq_nthreads; t++) {
 		VERIFY((tq->tq_threadlist[t] = thread_create(NULL, 0,
 		       taskq_thread, tq, THR_BOUND, NULL, 0, 0)) != NULL);
+		tq->tq_idlist[t] = tq->tq_threadlist[t]->t_tid;
+	}
 
 	return (tq);
 }
@@ -239,9 +246,10 @@ taskq_destroy(taskq_t *tq)
 	mutex_exit(&tq->tq_lock);
 
 	for (t = 0; t < nthreads; t++)
-		(void) thr_join(tq->tq_threadlist[t], NULL, NULL);
+		VERIFY3S(thread_join(tq->tq_idlist[t], NULL, NULL), ==, 0);
 
 	kmem_free(tq->tq_threadlist, nthreads * sizeof(kthread_t *));
+	kmem_free(tq->tq_idlist, nthreads * sizeof(kt_did_t));
 
 	rw_destroy(&tq->tq_threadlock);
 	mutex_destroy(&tq->tq_lock);
@@ -272,3 +280,9 @@ system_taskq_init(void)
 	system_taskq = taskq_create("system_taskq", 64, minclsyspri, 4, 512,
 	    TASKQ_DYNAMIC | TASKQ_PREPOPULATE);
 }
+
+void
+system_taskq_fini(void)
+{
+	taskq_destroy(system_taskq);
+}
diff --git a/module/zfs/txg.c b/module/zfs/txg.c
index e0bc524a3..fb95361f8 100644
--- a/module/zfs/txg.c
+++ b/module/zfs/txg.c
@@ -446,6 +446,8 @@ txg_sync_thread(dsl_pool_t *dp)
 		rw_exit(&tx->tx_suspend);
 		cv_broadcast(&tx->tx_sync_done_cv);
 	}
+
+	thread_exit();
 }
 
 static void
@@ -490,6 +492,8 @@ txg_quiesce_thread(dsl_pool_t *dp)
 		cv_broadcast(&tx->tx_sync_more_cv);
 		cv_broadcast(&tx->tx_quiesce_done_cv);
 	}
+
+	thread_exit();
 }
 
 /*