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-rw-r--r--src/internal/pthread_impl.h6
-rw-r--r--src/thread/pthread_rwlock_rdlock.c4
-rw-r--r--src/thread/pthread_rwlock_timedrdlock.c19
-rw-r--r--src/thread/pthread_rwlock_timedwrlock.c21
-rw-r--r--src/thread/pthread_rwlock_tryrdlock.c14
-rw-r--r--src/thread/pthread_rwlock_trywrlock.c8
-rw-r--r--src/thread/pthread_rwlock_unlock.c23
-rw-r--r--src/thread/pthread_rwlock_wrlock.c9
8 files changed, 44 insertions, 60 deletions
diff --git a/src/internal/pthread_impl.h b/src/internal/pthread_impl.h
index c11840d6..c853af88 100644
--- a/src/internal/pthread_impl.h
+++ b/src/internal/pthread_impl.h
@@ -67,10 +67,8 @@ struct __timer {
 #define _m_count __u.__i[5]
 #define _c_block __u.__i[0]
 #define _c_clock __u.__i[1]
-#define _rw_wrlock __u.__i[0]
-#define _rw_readers __u.__i[1]
-#define _rw_waiters __u.__i[2]
-#define _rw_owner __u.__i[3]
+#define _rw_lock __u.__i[0]
+#define _rw_waiters __u.__i[1]
 #define _b_inst __u.__p[0]
 #define _b_limit __u.__i[2]
 #define _b_lock __u.__i[3]
diff --git a/src/thread/pthread_rwlock_rdlock.c b/src/thread/pthread_rwlock_rdlock.c
index 29863507..0800d21f 100644
--- a/src/thread/pthread_rwlock_rdlock.c
+++ b/src/thread/pthread_rwlock_rdlock.c
@@ -2,7 +2,5 @@
 
 int pthread_rwlock_rdlock(pthread_rwlock_t *rw)
 {
-	while (pthread_rwlock_tryrdlock(rw))
-		__wait(&rw->_rw_wrlock, &rw->_rw_waiters, 1, 0);
-	return 0;
+	return pthread_rwlock_timedrdlock(rw, 0);
 }
diff --git a/src/thread/pthread_rwlock_timedrdlock.c b/src/thread/pthread_rwlock_timedrdlock.c
index a6f61b05..b5cb404a 100644
--- a/src/thread/pthread_rwlock_timedrdlock.c
+++ b/src/thread/pthread_rwlock_timedrdlock.c
@@ -2,14 +2,15 @@
 
 int pthread_rwlock_timedrdlock(pthread_rwlock_t *rw, const struct timespec *at)
 {
-	int w=0;
-	while (pthread_rwlock_tryrdlock(rw)) {
-		if (!w) a_inc(&rw->_rw_waiters), w++;
-		if (__timedwait(&rw->_rw_wrlock, 1, CLOCK_REALTIME, at, 0, 0, 0)==ETIMEDOUT) {
-			if (w) a_dec(&rw->_rw_waiters);
-			return ETIMEDOUT;
-		}
+	int r, t;
+	while ((r=pthread_rwlock_tryrdlock(rw))==EBUSY) {
+		if (!(r=rw->_rw_lock) || (r&0x7fffffff)!=0x7fffffff) continue;
+		t = r | 0x80000000;
+		a_inc(&rw->_rw_waiters);
+		a_cas(&rw->_rw_lock, r, t);
+		r = __timedwait(&rw->_rw_lock, t, CLOCK_REALTIME, at, 0, 0, 0);
+		a_dec(&rw->_rw_waiters);
+		if (r && r != EINTR) return r;
 	}
-	if (w) a_dec(&rw->_rw_waiters);
-	return 0;
+	return r;
 }
diff --git a/src/thread/pthread_rwlock_timedwrlock.c b/src/thread/pthread_rwlock_timedwrlock.c
index 484808e8..aa2fd199 100644
--- a/src/thread/pthread_rwlock_timedwrlock.c
+++ b/src/thread/pthread_rwlock_timedwrlock.c
@@ -2,16 +2,15 @@
 
 int pthread_rwlock_timedwrlock(pthread_rwlock_t *rw, const struct timespec *at)
 {
-	int nr, *p, w=0;
-	while (pthread_rwlock_trywrlock(rw)==EAGAIN) {
-		if (!w) a_inc(&rw->_rw_waiters), w++;
-		if ((nr=rw->_rw_readers)) p = &rw->_rw_readers;
-		else nr=1, p = &rw->_rw_wrlock;
-		if (__timedwait(p, nr, CLOCK_REALTIME, at, 0, 0, 0)==ETIMEDOUT) {
-			if (w) a_dec(&rw->_rw_waiters);
-			return ETIMEDOUT;
-		}
+	int r, t;
+	while ((r=pthread_rwlock_trywrlock(rw))==EBUSY) {
+		if (!(r=rw->_rw_lock)) continue;
+		t = r | 0x80000000;
+		a_inc(&rw->_rw_waiters);
+		a_cas(&rw->_rw_lock, r, t);
+		r = __timedwait(&rw->_rw_lock, t, CLOCK_REALTIME, at, 0, 0, 0);
+		a_dec(&rw->_rw_waiters);
+		if (r && r != EINTR) return r;
 	}
-	if (w) a_dec(&rw->_rw_waiters);
-	return 0;
+	return r;
 }
diff --git a/src/thread/pthread_rwlock_tryrdlock.c b/src/thread/pthread_rwlock_tryrdlock.c
index f860ec71..fa271fcc 100644
--- a/src/thread/pthread_rwlock_tryrdlock.c
+++ b/src/thread/pthread_rwlock_tryrdlock.c
@@ -2,12 +2,12 @@
 
 int pthread_rwlock_tryrdlock(pthread_rwlock_t *rw)
 {
-	a_inc(&rw->_rw_readers);
-	if (rw->_rw_wrlock) {
-		a_dec(&rw->_rw_readers);
-		if (rw->_rw_waiters && !rw->_rw_readers)
-			__wake(&rw->_rw_readers, 1, 0);
-		return EBUSY;
-	}
+	int val, cnt;
+	do {
+		val = rw->_rw_lock;
+		cnt = val & 0x7fffffff;
+		if (cnt == 0x7fffffff) return EBUSY;
+		if (cnt == 0x7ffffffe) return EAGAIN;
+	} while (a_cas(&rw->_rw_lock, val, val+1) != val);
 	return 0;
 }
diff --git a/src/thread/pthread_rwlock_trywrlock.c b/src/thread/pthread_rwlock_trywrlock.c
index 202e256a..bb3d3a99 100644
--- a/src/thread/pthread_rwlock_trywrlock.c
+++ b/src/thread/pthread_rwlock_trywrlock.c
@@ -2,12 +2,6 @@
 
 int pthread_rwlock_trywrlock(pthread_rwlock_t *rw)
 {
-	if (a_xchg(&rw->_rw_wrlock, 1))
-		return EBUSY;
-	if (rw->_rw_readers) {
-		a_store(&rw->_rw_wrlock, 0);
-		return EBUSY;
-	}
-	rw->_rw_owner = pthread_self()->tid;
+	if (a_cas(&rw->_rw_lock, 0, 0x7fffffff)) return EBUSY;
 	return 0;
 }
diff --git a/src/thread/pthread_rwlock_unlock.c b/src/thread/pthread_rwlock_unlock.c
index 060e3fe1..5edca634 100644
--- a/src/thread/pthread_rwlock_unlock.c
+++ b/src/thread/pthread_rwlock_unlock.c
@@ -2,16 +2,17 @@
 
 int pthread_rwlock_unlock(pthread_rwlock_t *rw)
 {
-	struct pthread *self = pthread_self();
-	if (rw->_rw_owner == self->tid) {
-		rw->_rw_owner = 0;
-		a_store(&rw->_rw_wrlock, 0);
-		if (rw->_rw_waiters)
-			__wake(&rw->_rw_wrlock, -1, 0);
-		return 0;
-	}
-	a_dec(&rw->_rw_readers);
-	if (rw->_rw_waiters && !rw->_rw_readers)
-		__wake(&rw->_rw_readers, 1, 0);
+	int val, cnt, waiters, new;
+
+	do {
+		val = rw->_rw_lock;
+		cnt = val & 0x7fffffff;
+		waiters = rw->_rw_waiters;
+		new = (cnt == 0x7fffffff || cnt == 1) ? 0 : val-1;
+	} while (a_cas(&rw->_rw_lock, val, new) != val);
+
+	if (!new && (waiters || val<0))
+		__wake(&rw->_rw_lock, 1, 0);
+
 	return 0;
 }
diff --git a/src/thread/pthread_rwlock_wrlock.c b/src/thread/pthread_rwlock_wrlock.c
index 8fd9ad1d..7f33535c 100644
--- a/src/thread/pthread_rwlock_wrlock.c
+++ b/src/thread/pthread_rwlock_wrlock.c
@@ -2,12 +2,5 @@
 
 int pthread_rwlock_wrlock(pthread_rwlock_t *rw)
 {
-	int nr;
-	while (pthread_rwlock_trywrlock(rw)==EAGAIN) {
-		if ((nr=rw->_rw_readers))
-			__wait(&rw->_rw_readers, &rw->_rw_waiters, nr, 0);
-		else
-			__wait(&rw->_rw_wrlock, &rw->_rw_waiters, 1, 0);
-	}
-	return 0;
+	return pthread_rwlock_timedwrlock(rw, 0);
 }