Fix Solaris thread dependency by using pthreads

This is a portability change which removes the dependence of the Solaris thread library. All locations where Solaris thread API was used before have been replaced with equivilant Solaris kernel style thread calls. In user space the kernel style threading API is implemented in term of the portable pthreads library. This includes all threads, mutexs, condition variables, reader/writer locks, and taskqs. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2026-05-22 02:27:36 +03:00 · 2010-08-26 10:43:27 -07:00
parent 8a8f5c6b3c
commit 1e33ac1e26
5 changed files with 481 additions and 252 deletions
@@ -29,6 +29,7 @@
 #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>
@@ -57,16 +58,156 @@ struct proc p0;
 * threads
 * =========================================================================
 */
-/*ARGSUSED*/
-kthread_t *
-zk_thread_create(void (*func)(), void *arg)
+
+pthread_cond_t kthread_cond = PTHREAD_COND_INITIALIZER;
+pthread_mutex_t kthread_lock = PTHREAD_MUTEX_INITIALIZER;
+pthread_key_t kthread_key;
+int kthread_nr = 0;
+
+static void
+thread_init(void)
 {
-	thread_t tid;
+	kthread_t *kt;

-	VERIFY(thr_create(0, 0, (void *(*)(void *))func, arg, THR_DETACHED,
-	    &tid) == 0);
+	VERIFY3S(pthread_key_create(&kthread_key, NULL), ==, 0);

-	return ((void *)(uintptr_t)tid);
+	/* Create entry for primary kthread */
+	kt = umem_zalloc(sizeof(kthread_t), UMEM_NOFAIL);
+	kt->t_tid = pthread_self();
+	kt->t_func = NULL;
+
+	VERIFY3S(pthread_setspecific(kthread_key, kt), ==, 0);
+
+	/* Only the main thread should be running at the moment */
+	ASSERT3S(kthread_nr, ==, 0);
+	kthread_nr = 1;
+}
+
+static void
+thread_fini(void)
+{
+	kthread_t *kt = curthread;
+
+	ASSERT(pthread_equal(kt->t_tid, pthread_self()));
+	ASSERT3P(kt->t_func, ==, NULL);
+
+	umem_free(kt, sizeof(kthread_t));
+
+	/* Wait for all threads to exit via thread_exit() */
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
+
+	kthread_nr--; /* Main thread is exiting */
+
+	while (kthread_nr > 0)
+		VERIFY3S(pthread_cond_wait(&kthread_cond, &kthread_lock), ==,
+		    0);
+
+	ASSERT3S(kthread_nr, ==, 0);
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
+
+	VERIFY3S(pthread_key_delete(kthread_key), ==, 0);
+}
+
+kthread_t *
+zk_thread_current(void)
+{
+	kthread_t *kt = pthread_getspecific(kthread_key);
+
+	ASSERT3P(kt, !=, NULL);
+
+	return kt;
+}
+
+void *
+zk_thread_helper(void *arg)
+{
+	kthread_t *kt = (kthread_t *) arg;
+
+	VERIFY3S(pthread_setspecific(kthread_key, kt), ==, 0);
+
+	VERIFY3S(pthread_mutex_lock(&kthread_lock), ==, 0);
+	kthread_nr++;
+	VERIFY3S(pthread_mutex_unlock(&kthread_lock), ==, 0);
+
+	kt->t_tid = pthread_self();
+	((thread_func_arg_t) kt->t_func)(kt->t_arg);
+
+	/* Unreachable, thread must exit with thread_exit() */
+	abort();
+
+	return NULL;
+}
+
+kthread_t *
+zk_thread_create(caddr_t stk, size_t stksize, thread_func_t func, void *arg,
+	      size_t len, proc_t *pp, int state, pri_t pri)
+{
+	kthread_t *kt;
+	pthread_attr_t attr;
+	size_t stack;
+
+	ASSERT3S(state & ~TS_RUN, ==, 0);
+
+	kt = umem_zalloc(sizeof(kthread_t), UMEM_NOFAIL);
+	kt->t_func = func;
+	kt->t_arg = arg;
+
+	/*
+	 * The Solaris kernel stack size is 24k for x86/x86_64.
+	 * The Linux kernel stack size is 8k for x86/x86_64.
+	 *
+	 * We reduce the default stack size in userspace, to ensure
+	 * we observe stack overruns in user space as well as in
+	 * kernel space.  PTHREAD_STACK_MIN is the minimum stack
+	 * required for a NULL procedure in user space and is added
+	 * in to the stack requirements.
+	 *
+	 * Some buggy NPTL threading implementations include the
+	 * guard area within the stack size allocations.  In
+	 * this case we allocate an extra page to account for the
+	 * guard area since we only have two pages of usable stack
+	 * on Linux.
+	 */
+
+	stack = PTHREAD_STACK_MIN + MAX(stksize, STACK_SIZE) +
+			EXTRA_GUARD_BYTES;
+
+	VERIFY3S(pthread_attr_init(&attr), ==, 0);
+	VERIFY3S(pthread_attr_setstacksize(&attr, stack), ==, 0);
+	VERIFY3S(pthread_attr_setguardsize(&attr, PAGESIZE), ==, 0);
+
+	VERIFY3S(pthread_create(&kt->t_tid, &attr, &zk_thread_helper, kt),
+	    ==, 0);
+
+	VERIFY3S(pthread_attr_destroy(&attr), ==, 0);
+
+	return kt;
+}
+
+void
+zk_thread_exit(void)
+{
+	kthread_t *kt = curthread;
+
+	ASSERT(pthread_equal(kt->t_tid, pthread_self()));
+
+	umem_free(kt, sizeof(kthread_t));
+
+	pthread_mutex_lock(&kthread_lock);
+	kthread_nr--;
+	pthread_mutex_unlock(&kthread_lock);
+
+	pthread_cond_broadcast(&kthread_cond);
+	pthread_exit((void *)TS_MAGIC);
+}
+
+void
+zk_thread_join(kt_did_t tid)
+{
+	void *ret;
+
+	pthread_join((pthread_t)tid, &ret);
+	VERIFY3P(ret, ==, (void *)TS_MAGIC);
 }

 /*
@@ -97,42 +238,45 @@ kstat_delete(kstat_t *ksp)
 * mutexes
 * =========================================================================
 */
+
 void
-zmutex_init(kmutex_t *mp)
+mutex_init(kmutex_t *mp, char *name, int type, void *cookie)
 {
-	mp->m_owner = NULL;
-	mp->initialized = B_TRUE;
-	(void) _mutex_init(&mp->m_lock, USYNC_THREAD, NULL);
+	ASSERT3S(type, ==, MUTEX_DEFAULT);
+	ASSERT3P(cookie, ==, NULL);
+	mp->m_owner = MTX_INIT;
+	mp->m_magic = MTX_MAGIC;
+	VERIFY3S(pthread_mutex_init(&mp->m_lock, NULL), ==, 0);
 }

 void
-zmutex_destroy(kmutex_t *mp)
+mutex_destroy(kmutex_t *mp)
 {
-	ASSERT(mp->initialized == B_TRUE);
-	ASSERT(mp->m_owner == NULL);
-	(void) _mutex_destroy(&(mp)->m_lock);
-	mp->m_owner = (void *)-1UL;
-	mp->initialized = B_FALSE;
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mp->m_owner, ==, MTX_INIT);
+	VERIFY3S(pthread_mutex_destroy(&(mp)->m_lock), ==, 0);
+	mp->m_owner = MTX_DEST;
+	mp->m_magic = 0;
 }

 void
 mutex_enter(kmutex_t *mp)
 {
-	ASSERT(mp->initialized == B_TRUE);
-	ASSERT(mp->m_owner != (void *)-1UL);
-	ASSERT(mp->m_owner != curthread);
-	VERIFY(mutex_lock(&mp->m_lock) == 0);
-	ASSERT(mp->m_owner == NULL);
+	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);
+	ASSERT3P(mp->m_owner, ==, MTX_INIT);
 	mp->m_owner = curthread;
 }

 int
 mutex_tryenter(kmutex_t *mp)
 {
-	ASSERT(mp->initialized == B_TRUE);
-	ASSERT(mp->m_owner != (void *)-1UL);
-	if (0 == mutex_trylock(&mp->m_lock)) {
-		ASSERT(mp->m_owner == NULL);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
+	ASSERT3P(mp->m_owner, !=, MTX_DEST);
+	if (0 == pthread_mutex_trylock(&mp->m_lock)) {
+		ASSERT3P(mp->m_owner, ==, MTX_INIT);
 		mp->m_owner = curthread;
 		return (1);
 	} else {
@@ -143,53 +287,71 @@ mutex_tryenter(kmutex_t *mp)
 void
 mutex_exit(kmutex_t *mp)
 {
-	ASSERT(mp->initialized == B_TRUE);
-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
-	VERIFY(mutex_unlock(&mp->m_lock) == 0);
+	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->initialized == B_TRUE);
+	ASSERT3U(mp->m_magic, ==, MTX_MAGIC);
 	return (mp->m_owner);
 }

+int
+mutex_held(kmutex_t *mp)
+{
+	return (mp->m_owner == curthread);
+}
+
 /*
 * =========================================================================
 * rwlocks
 * =========================================================================
 */
-/*ARGSUSED*/
+
 void
 rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
 {
-	rwlock_init(&rwlp->rw_lock, USYNC_THREAD, NULL);
-	rwlp->rw_owner = NULL;
-	rwlp->initialized = B_TRUE;
+	ASSERT3S(type, ==, RW_DEFAULT);
+	ASSERT3P(arg, ==, NULL);
+	VERIFY3S(pthread_rwlock_init(&rwlp->rw_lock, NULL), ==, 0);
+	rwlp->rw_owner = RW_INIT;
+	rwlp->rw_wr_owner = RW_INIT;
+	rwlp->rw_readers = 0;
+	rwlp->rw_magic = RW_MAGIC;
 }

 void
 rw_destroy(krwlock_t *rwlp)
 {
-	rwlock_destroy(&rwlp->rw_lock);
-	rwlp->rw_owner = (void *)-1UL;
-	rwlp->initialized = B_FALSE;
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
+
+	VERIFY3S(pthread_rwlock_destroy(&rwlp->rw_lock), ==, 0);
+	rwlp->rw_magic = 0;
 }

 void
 rw_enter(krwlock_t *rwlp, krw_t rw)
 {
-	ASSERT(!RW_LOCK_HELD(rwlp));
-	ASSERT(rwlp->initialized == B_TRUE);
-	ASSERT(rwlp->rw_owner != (void *)-1UL);
-	ASSERT(rwlp->rw_owner != curthread);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
+	ASSERT3P(rwlp->rw_owner, !=, curthread);
+	ASSERT3P(rwlp->rw_wr_owner, !=, curthread);

-	if (rw == RW_READER)
-		VERIFY(rw_rdlock(&rwlp->rw_lock) == 0);
-	else
-		VERIFY(rw_wrlock(&rwlp->rw_lock) == 0);
+	if (rw == RW_READER) {
+		VERIFY3S(pthread_rwlock_rdlock(&rwlp->rw_lock), ==, 0);
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
+
+		atomic_inc_uint(&rwlp->rw_readers);
+	} else {
+		VERIFY3S(pthread_rwlock_wrlock(&rwlp->rw_lock), ==, 0);
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
+		ASSERT3U(rwlp->rw_readers, ==, 0);
+
+		rwlp->rw_wr_owner = curthread;
+	}

 	rwlp->rw_owner = curthread;
 }
@@ -197,11 +359,16 @@ rw_enter(krwlock_t *rwlp, krw_t rw)
 void
 rw_exit(krwlock_t *rwlp)
 {
-	ASSERT(rwlp->initialized == B_TRUE);
-	ASSERT(rwlp->rw_owner != (void *)-1UL);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);
+	ASSERT(RW_LOCK_HELD(rwlp));

-	rwlp->rw_owner = NULL;
-	VERIFY(rw_unlock(&rwlp->rw_lock) == 0);
+	if (RW_READ_HELD(rwlp))
+		atomic_dec_uint(&rwlp->rw_readers);
+	else
+		rwlp->rw_wr_owner = RW_INIT;
+
+	rwlp->rw_owner = RW_INIT;
+	VERIFY3S(pthread_rwlock_unlock(&rwlp->rw_lock), ==, 0);
 }

 int
@@ -209,28 +376,36 @@ rw_tryenter(krwlock_t *rwlp, krw_t rw)
 {
 	int rv;

-	ASSERT(rwlp->initialized == B_TRUE);
-	ASSERT(rwlp->rw_owner != (void *)-1UL);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);

 	if (rw == RW_READER)
-		rv = rw_tryrdlock(&rwlp->rw_lock);
+		rv = pthread_rwlock_tryrdlock(&rwlp->rw_lock);
 	else
-		rv = rw_trywrlock(&rwlp->rw_lock);
+		rv = pthread_rwlock_trywrlock(&rwlp->rw_lock);

 	if (rv == 0) {
+		ASSERT3P(rwlp->rw_wr_owner, ==, RW_INIT);
+
+		if (rw == RW_READER)
+			atomic_inc_uint(&rwlp->rw_readers);
+		else {
+			ASSERT3U(rwlp->rw_readers, ==, 0);
+			rwlp->rw_wr_owner = curthread;
+		}
+
 		rwlp->rw_owner = curthread;
 		return (1);
 	}

+	VERIFY3S(rv, ==, EBUSY);
+
 	return (0);
 }

-/*ARGSUSED*/
 int
 rw_tryupgrade(krwlock_t *rwlp)
 {
-	ASSERT(rwlp->initialized == B_TRUE);
-	ASSERT(rwlp->rw_owner != (void *)-1UL);
+	ASSERT3U(rwlp->rw_magic, ==, RW_MAGIC);

 	return (0);
 }
@@ -240,26 +415,32 @@ rw_tryupgrade(krwlock_t *rwlp)
 * condition variables
 * =========================================================================
 */
-/*ARGSUSED*/
+
 void
 cv_init(kcondvar_t *cv, char *name, int type, void *arg)
 {
-	VERIFY(cond_init(cv, type, NULL) == 0);
+	ASSERT3S(type, ==, CV_DEFAULT);
+	cv->cv_magic = CV_MAGIC;
+	VERIFY3S(pthread_cond_init(&cv->cv, NULL), ==, 0);
 }

 void
 cv_destroy(kcondvar_t *cv)
 {
-	VERIFY(cond_destroy(cv) == 0);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
+	VERIFY3S(pthread_cond_destroy(&cv->cv), ==, 0);
+	cv->cv_magic = 0;
 }

 void
 cv_wait(kcondvar_t *cv, kmutex_t *mp)
 {
-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
-	int ret = cond_wait(cv, &mp->m_lock);
-	VERIFY(ret == 0 || ret == EINTR);
+	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);
 	mp->m_owner = curthread;
 }

@@ -267,29 +448,38 @@ clock_t
 cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
 {
 	int error;
+	struct timeval tv;
 	timestruc_t ts;
 	clock_t delta;

+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
+
 top:
 	delta = abstime - ddi_get_lbolt();
 	if (delta <= 0)
 		return (-1);

-	ts.tv_sec = delta / hz;
-	ts.tv_nsec = (delta % hz) * (NANOSEC / hz);
+	VERIFY(gettimeofday(&tv, NULL) == 0);

-	ASSERT(mutex_owner(mp) == curthread);
-	mp->m_owner = NULL;
-	error = cond_reltimedwait(cv, &mp->m_lock, &ts);
+	ts.tv_sec = tv.tv_sec + delta / hz;
+	ts.tv_nsec = tv.tv_usec * 1000 + (delta % hz) * (NANOSEC / hz);
+	if (ts.tv_nsec >= NANOSEC) {
+		ts.tv_sec++;
+		ts.tv_nsec -= NANOSEC;
+	}
+
+	ASSERT3P(mutex_owner(mp), ==, curthread);
+	mp->m_owner = MTX_INIT;
+	error = pthread_cond_timedwait(&cv->cv, &mp->m_lock, &ts);
 	mp->m_owner = curthread;

-	if (error == ETIME)
+	if (error == ETIMEDOUT)
 		return (-1);

 	if (error == EINTR)
 		goto top;

-	ASSERT(error == 0);
+	VERIFY3S(error, ==, 0);

 	return (1);
 }
@@ -297,13 +487,15 @@ top:
 void
 cv_signal(kcondvar_t *cv)
 {
-	VERIFY(cond_signal(cv) == 0);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
+	VERIFY3S(pthread_cond_signal(&cv->cv), ==, 0);
 }

 void
 cv_broadcast(kcondvar_t *cv)
 {
-	VERIFY(cond_broadcast(cv) == 0);
+	ASSERT3U(cv->cv_magic, ==, CV_MAGIC);
+	VERIFY3S(pthread_cond_broadcast(&cv->cv), ==, 0);
 }

 /*
@@ -571,7 +763,7 @@ __dprintf(const char *file, const char *func, int line, const char *fmt, ...)
 		if (dprintf_find_string("pid"))
 			(void) printf("%d ", getpid());
 		if (dprintf_find_string("tid"))
-			(void) printf("%u ", thr_self());
+			(void) printf("%u ", (uint_t) pthread_self());
 		if (dprintf_find_string("cpu"))
 			(void) printf("%u ", getcpuid());
 		if (dprintf_find_string("time"))
@@ -824,6 +1016,7 @@ kernel_init(int mode)
 	VERIFY((random_fd = open("/dev/random", O_RDONLY)) != -1);
 	VERIFY((urandom_fd = open("/dev/urandom", O_RDONLY)) != -1);

+	thread_init();
 	system_taskq_init();

 	spa_init(mode);
@@ -835,6 +1028,7 @@ kernel_fini(void)
 	spa_fini();

 	system_taskq_fini();
+	thread_fini();

 	close(random_fd);
 	close(urandom_fd);