PERFORCE change 68289 for review

[David Xu]

http://perforce.freebsd.org/chv.cgi?CH=68289

Change 68289 by davidxu at davidxu_celeron on 2005/01/05 02:41:17

	A deadlock can be timeouted if timeout is specified.

Affected files ...

.. //depot/projects/davidxu_thread/src/lib/libthread/thread/thr_mutex.c#10 edit

Differences ...

==== //depot/projects/davidxu_thread/src/lib/libthread/thread/thr_mutex.c#10 (text+ko) ====

@@ -75,7 +75,8 @@
  */
 static long		mutex_handoff(struct pthread *, struct pthread_mutex *);
 static inline int	mutex_self_trylock(struct pthread *, pthread_mutex_t);
-static inline int	mutex_self_lock(struct pthread *, pthread_mutex_t);
+static inline int	mutex_self_lock(struct pthread *, pthread_mutex_t,
+				const struct timespec *abstime);
 static int		mutex_unlock_common(pthread_mutex_t *, int);
 static void		mutex_priority_adjust(struct pthread *, pthread_mutex_t);
 static void		mutex_rescan_owned (struct pthread *, struct pthread *,
@@ -515,14 +516,8 @@
 			TAILQ_INSERT_TAIL(&curthread->mutexq,
 			    (*m), m_qe);
 #endif
-		} else if (umtx_owner(&(*m)->m_lock) == curthread->tid &&
-			   (*m)->m_type != PTHREAD_MUTEX_NORMAL) {
-			/*
-			 * We don't do deadlock sleep in mutex_self_lock
-			 * if type is normal, instead let umtx_lock sleep
-			 * in kernel.
-			 */
-			ret = mutex_self_lock(curthread, *m);
+		} else if (umtx_owner(&(*m)->m_lock) == curthread->tid) {
+			ret = mutex_self_lock(curthread, *m, abstime);
 		} else {
 			if (abstime == NULL) {
 				UMTX_LOCK(&(*m)->m_lock, curthread->tid);
@@ -611,7 +606,7 @@
 				/* Unlock the mutex structure: */
 				THR_LOCK_RELEASE(curthread, &(*m)->m_lock);
 			} else if ((*m)->m_owner == curthread) {
-				ret = mutex_self_lock(curthread, *m);
+				ret = mutex_self_lock(curthread, *m, abstime);
 
 				/* Unlock the mutex structure: */
 				THR_LOCK_RELEASE(curthread, &(*m)->m_lock);
@@ -701,7 +696,7 @@
 				/* Unlock the mutex structure: */
 				THR_LOCK_RELEASE(curthread, &(*m)->m_lock);
 			} else if ((*m)->m_owner == curthread) {
-				ret = mutex_self_lock(curthread, *m);
+				ret = mutex_self_lock(curthread, *m, abstime);
 
 				/* Unlock the mutex structure: */
 				THR_LOCK_RELEASE(curthread, &(*m)->m_lock);
@@ -926,9 +921,10 @@
 }
 
 static inline int
-mutex_self_lock(struct pthread *curthread, pthread_mutex_t m)
+mutex_self_lock(struct pthread *curthread, pthread_mutex_t m,
+	const struct timespec *abstime)
 {
-	struct timespec ts;
+	struct timespec ts1, ts2;
 	int ret;
 
 	switch (m->m_type) {
@@ -946,18 +942,22 @@
 		 * What SS2 define as a 'normal' mutex.  Intentionally
 		 * deadlock on attempts to get a lock you already own.
 		 */
+		ret = 0;
 		if (m->m_protocol != PTHREAD_PRIO_NONE) {
 			/* Unlock the mutex structure: */
 			THR_LOCK_RELEASE(curthread, &m->m_lock);
-			ts.tv_sec = 30;
-			ts.tv_nsec = 0;
+		}
+		if (abstime) {
+			clock_gettime(CLOCK_REALTIME, &ts1);
+			TIMESPEC_SUB(&ts2, abstime, &ts1);
+			__sys_nanosleep(&ts2, NULL);
+			ret = ETIMEDOUT;
+		} else {
+			ts1.tv_sec = 30;
+			ts1.tv_nsec = 0;
 			for (;;)
-				__sys_nanosleep(&ts, NULL);
-		} else {
-			PANIC("shouldn't be here!\n");
+				__sys_nanosleep(&ts1, NULL);
 		}
-
-		ret = 0;
 		break;
 
 	case PTHREAD_MUTEX_RECURSIVE: