Some boring fixes (mainly protection against spurious wakeups from cond_wait)

diff --git a/src/threads/native/threads.c b/src/threads/native/threads.c
index 5c130cc701e6b8934967019ac38ed0f6fbeb3fe3..bd60b801d1dff5b3b26728e3bd67ad2c1812802a 100644 (file)
--- a/src/threads/native/threads.c
+++ b/src/threads/native/threads.c
@@ -356,7 +356,7 @@ static void sigsuspend_handler(ucontext_t *ctx)
 
        /* Do as Boehm does. On IRIX a condition variable is used for wake-up
           (not POSIX async-safe). */
-#if defined(__MIPS__)
+#if defined(__IRIX__)
        pthread_mutex_lock(&suspend_ack_lock);
        sem_post(&suspend_ack);
        pthread_cond_wait(&suspend_cond, &suspend_ack_lock);
@@ -533,8 +533,6 @@ initThreads(u1 *stackbottom)
        if (*exceptionptr)
                throw_exception_exit();
 
-       /* TODO InheritableThreadLocal */
-
        setPriority(pthread_self(), 5);
 
        pthread_attr_init(&threadattr);
@@ -546,11 +544,15 @@ void initThread(java_lang_VMThread *t)
        threadobject *thread = (threadobject*) t;
        nativethread *info = &thread->info;
        info->tid = pthread_self();
+       /* TODO destroy all those things */
        pthread_mutex_init(&info->joinMutex, NULL);
        pthread_cond_init(&info->joinCond, NULL);
 
-       thread->interrupted = 0;
-       thread->waiting = NULL;
+       pthread_mutex_init(&thread->waitLock, NULL);
+       pthread_cond_init(&thread->waitCond, NULL);
+       thread->interrupted = false;
+       thread->signaled = false;
+       thread->isSleeping = false;
 }
 
 static void initThreadLocks(threadobject *);
@@ -662,7 +664,7 @@ void joinAllThreads()
                nativethread *info = &thread->info;
                pthread_mutex_lock(&info->joinMutex);
                pthread_mutex_unlock(&threadlistlock);
-               if (info->tid)
+               while (info->tid)
                        pthread_cond_wait(&info->joinCond, &info->joinMutex);
                pthread_mutex_unlock(&info->joinMutex);
                pthread_mutex_lock(&threadlistlock);
@@ -682,8 +684,6 @@ static void initLockRecord(monitorLockRecord *r, threadobject *t)
        sem_init(&r->queueSem, 0, 0);
        pthread_mutex_init(&r->resolveLock, NULL);
        pthread_cond_init(&r->resolveWait, NULL);
-       pthread_mutex_init(&r->waitLock, NULL);
-       pthread_cond_init(&r->waitCond, NULL);
 }
 
 /* No lock record must ever be destroyed because there may still be references
@@ -694,8 +694,6 @@ static void destroyLockRecord(monitorLockRecord *r)
        sem_destroy(&r->queueSem);
        pthread_mutex_destroy(&r->resolveLock);
        pthread_cond_destroy(&r->resolveWait);
-       pthread_mutex_destroy(&r->waitLock);
-       pthread_cond_destroy(&r->waitCond);
 }
 */
 
@@ -798,7 +796,7 @@ static void queueOnLockRecord(monitorLockRecord *lr, java_objectheader *o)
 {
        atomic_add(&lr->queuers, 1);
        MEMORY_BARRIER_AFTER_ATOMIC();
-       if (lr->o == o)
+       while (lr->o == o)
                sem_wait(&lr->queueSem);
        atomic_add(&lr->queuers, -1);
 }
@@ -920,19 +918,38 @@ static void removeFromWaiters(monitorLockRecord *lr, monitorLockRecord *wlr)
        } while (lr);
 }
 
+static inline bool timespec_less(const struct timespec *tv1, const struct timespec *tv2)
+{
+       return tv1->tv_sec < tv2->tv_sec || (tv1->tv_sec == tv2->tv_sec && tv1->tv_nsec < tv2->tv_nsec);
+}
+
+static bool timeIsEarlier(const struct timespec *tv)
+{
+       struct timeval tvnow;
+       struct timespec tsnow;
+       gettimeofday(&tvnow, NULL);
+       tsnow.tv_sec = tvnow.tv_sec;
+       tsnow.tv_nsec = tvnow.tv_usec * 1000;
+       return timespec_less(&tsnow, tv);
+}
+
 bool waitWithTimeout(threadobject *t, monitorLockRecord *lr, struct timespec *wakeupTime)
 {
        bool wasinterrupted;
 
-       pthread_mutex_lock(&lr->waitLock);
-       t->waiting = lr;
+       pthread_mutex_lock(&t->waitLock);
+       t->isSleeping = true;
        if (wakeupTime->tv_sec || wakeupTime->tv_nsec)
-               pthread_cond_timedwait(&lr->waitCond, &lr->waitLock, wakeupTime);
+               while (!t->interrupted && !t->signaled && timeIsEarlier(wakeupTime))
+                       pthread_cond_timedwait(&t->waitCond, &t->waitLock, wakeupTime);
        else
-               pthread_cond_wait(&lr->waitCond, &lr->waitLock);
-       wasinterrupted = t->waiting == NULL;
-       t->waiting = NULL;
-       pthread_mutex_unlock(&lr->waitLock);
+               while (!t->interrupted && !t->signaled)
+                       pthread_cond_wait(&t->waitCond, &t->waitLock);
+       wasinterrupted = t->interrupted;
+       t->interrupted = false;
+       t->signaled = false;
+       t->isSleeping = false;
+       pthread_mutex_unlock(&t->waitLock);
        return wasinterrupted;
 }
 
@@ -987,10 +1004,16 @@ static void notifyOneOrAll(threadobject *t, java_objectheader *o, bool one)
        GRAB_LR(lr, t);
        CHECK_MONITORSTATE(lr, t, o, return);
        do {
+               threadobject *wthread;
                monitorLockRecord *wlr = lr->waiter;
                if (!wlr)
                        break;
-               pthread_cond_signal(&wlr->waitCond);
+               wthread = wlr->ownerThread;
+               pthread_mutex_lock(&wthread->waitLock);
+               if (wthread->isSleeping)
+                       pthread_cond_signal(&wthread->waitCond);
+               wthread->signaled = true;
+               pthread_mutex_unlock(&wthread->waitLock);
                lr = wlr;
        } while (!one);
 }
@@ -1006,25 +1029,18 @@ void interruptThread(java_lang_VMThread *thread)
 {
        threadobject *t = (threadobject*) thread;
 
-       monitorLockRecord *lr = t->waiting;
-       if (lr) {
-               pthread_mutex_lock(&lr->waitLock);
-               if (t->waiting == lr) {
-                       t->waiting = NULL;
-                       pthread_cond_signal(&lr->waitCond);
-               }
-               pthread_mutex_unlock(&lr->waitLock);
-               return;
-       }
-       
-       t->interrupted = 1;
+       t->interrupted = true;
+       pthread_mutex_lock(&t->waitLock);
+       if (t->isSleeping)
+               pthread_cond_signal(&t->waitCond);
+       pthread_mutex_unlock(&t->waitLock);
 }
 
 bool interruptedThread()
 {
        threadobject *t = (threadobject*) THREADOBJECT;
-       long intr = t->interrupted;
-       t->interrupted = 0;
+       bool intr = t->interrupted;
+       t->interrupted = false;
        return intr;
 }
 

diff --git a/src/threads/native/threads.h b/src/threads/native/threads.h
index 229414b447b23acd3fa34fbfaecdbdd7445fff11..db55fa4e041d6ff8b020277b804e5fc82379aaa6 100644 (file)
--- a/src/threads/native/threads.h
+++ b/src/threads/native/threads.h
@@ -25,8 +25,8 @@ typedef struct _monitorLockRecord {
        struct _monitorLockRecord *waiter, *incharge;
        bool waiting;
        sem_t queueSem;
-       pthread_mutex_t resolveLock, waitLock;
-       pthread_cond_t resolveWait, waitCond;
+       pthread_mutex_t resolveLock;
+       pthread_cond_t resolveWait;
 } monitorLockRecord;
 
 struct _lockRecordPool;
@@ -68,8 +68,9 @@ typedef struct _threadobject {
        nativethread info;
        ExecEnvironment ee;
 
-       long interrupted;
-       monitorLockRecord *waiting;
+       pthread_mutex_t waitLock;
+       pthread_cond_t waitCond;
+       bool interrupted, signaled, isSleeping;
 } threadobject;
 
 monitorLockRecord *monitorEnter(threadobject *, java_objectheader *);

diff --git a/threads/nativethread.c b/threads/nativethread.c
index 5c130cc701e6b8934967019ac38ed0f6fbeb3fe3..bd60b801d1dff5b3b26728e3bd67ad2c1812802a 100644 (file)
--- a/threads/nativethread.c
+++ b/threads/nativethread.c
@@ -356,7 +356,7 @@ static void sigsuspend_handler(ucontext_t *ctx)
 
        /* Do as Boehm does. On IRIX a condition variable is used for wake-up
           (not POSIX async-safe). */
-#if defined(__MIPS__)
+#if defined(__IRIX__)
        pthread_mutex_lock(&suspend_ack_lock);
        sem_post(&suspend_ack);
        pthread_cond_wait(&suspend_cond, &suspend_ack_lock);
@@ -533,8 +533,6 @@ initThreads(u1 *stackbottom)
        if (*exceptionptr)
                throw_exception_exit();
 
-       /* TODO InheritableThreadLocal */
-
        setPriority(pthread_self(), 5);
 
        pthread_attr_init(&threadattr);
@@ -546,11 +544,15 @@ void initThread(java_lang_VMThread *t)
        threadobject *thread = (threadobject*) t;
        nativethread *info = &thread->info;
        info->tid = pthread_self();
+       /* TODO destroy all those things */
        pthread_mutex_init(&info->joinMutex, NULL);
        pthread_cond_init(&info->joinCond, NULL);
 
-       thread->interrupted = 0;
-       thread->waiting = NULL;
+       pthread_mutex_init(&thread->waitLock, NULL);
+       pthread_cond_init(&thread->waitCond, NULL);
+       thread->interrupted = false;
+       thread->signaled = false;
+       thread->isSleeping = false;
 }
 
 static void initThreadLocks(threadobject *);
@@ -662,7 +664,7 @@ void joinAllThreads()
                nativethread *info = &thread->info;
                pthread_mutex_lock(&info->joinMutex);
                pthread_mutex_unlock(&threadlistlock);
-               if (info->tid)
+               while (info->tid)
                        pthread_cond_wait(&info->joinCond, &info->joinMutex);
                pthread_mutex_unlock(&info->joinMutex);
                pthread_mutex_lock(&threadlistlock);
@@ -682,8 +684,6 @@ static void initLockRecord(monitorLockRecord *r, threadobject *t)
        sem_init(&r->queueSem, 0, 0);
        pthread_mutex_init(&r->resolveLock, NULL);
        pthread_cond_init(&r->resolveWait, NULL);
-       pthread_mutex_init(&r->waitLock, NULL);
-       pthread_cond_init(&r->waitCond, NULL);
 }
 
 /* No lock record must ever be destroyed because there may still be references
@@ -694,8 +694,6 @@ static void destroyLockRecord(monitorLockRecord *r)
        sem_destroy(&r->queueSem);
        pthread_mutex_destroy(&r->resolveLock);
        pthread_cond_destroy(&r->resolveWait);
-       pthread_mutex_destroy(&r->waitLock);
-       pthread_cond_destroy(&r->waitCond);
 }
 */
 
@@ -798,7 +796,7 @@ static void queueOnLockRecord(monitorLockRecord *lr, java_objectheader *o)
 {
        atomic_add(&lr->queuers, 1);
        MEMORY_BARRIER_AFTER_ATOMIC();
-       if (lr->o == o)
+       while (lr->o == o)
                sem_wait(&lr->queueSem);
        atomic_add(&lr->queuers, -1);
 }
@@ -920,19 +918,38 @@ static void removeFromWaiters(monitorLockRecord *lr, monitorLockRecord *wlr)
        } while (lr);
 }
 
+static inline bool timespec_less(const struct timespec *tv1, const struct timespec *tv2)
+{
+       return tv1->tv_sec < tv2->tv_sec || (tv1->tv_sec == tv2->tv_sec && tv1->tv_nsec < tv2->tv_nsec);
+}
+
+static bool timeIsEarlier(const struct timespec *tv)
+{
+       struct timeval tvnow;
+       struct timespec tsnow;
+       gettimeofday(&tvnow, NULL);
+       tsnow.tv_sec = tvnow.tv_sec;
+       tsnow.tv_nsec = tvnow.tv_usec * 1000;
+       return timespec_less(&tsnow, tv);
+}
+
 bool waitWithTimeout(threadobject *t, monitorLockRecord *lr, struct timespec *wakeupTime)
 {
        bool wasinterrupted;
 
-       pthread_mutex_lock(&lr->waitLock);
-       t->waiting = lr;
+       pthread_mutex_lock(&t->waitLock);
+       t->isSleeping = true;
        if (wakeupTime->tv_sec || wakeupTime->tv_nsec)
-               pthread_cond_timedwait(&lr->waitCond, &lr->waitLock, wakeupTime);
+               while (!t->interrupted && !t->signaled && timeIsEarlier(wakeupTime))
+                       pthread_cond_timedwait(&t->waitCond, &t->waitLock, wakeupTime);
        else
-               pthread_cond_wait(&lr->waitCond, &lr->waitLock);
-       wasinterrupted = t->waiting == NULL;
-       t->waiting = NULL;
-       pthread_mutex_unlock(&lr->waitLock);
+               while (!t->interrupted && !t->signaled)
+                       pthread_cond_wait(&t->waitCond, &t->waitLock);
+       wasinterrupted = t->interrupted;
+       t->interrupted = false;
+       t->signaled = false;
+       t->isSleeping = false;
+       pthread_mutex_unlock(&t->waitLock);
        return wasinterrupted;
 }
 
@@ -987,10 +1004,16 @@ static void notifyOneOrAll(threadobject *t, java_objectheader *o, bool one)
        GRAB_LR(lr, t);
        CHECK_MONITORSTATE(lr, t, o, return);
        do {
+               threadobject *wthread;
                monitorLockRecord *wlr = lr->waiter;
                if (!wlr)
                        break;
-               pthread_cond_signal(&wlr->waitCond);
+               wthread = wlr->ownerThread;
+               pthread_mutex_lock(&wthread->waitLock);
+               if (wthread->isSleeping)
+                       pthread_cond_signal(&wthread->waitCond);
+               wthread->signaled = true;
+               pthread_mutex_unlock(&wthread->waitLock);
                lr = wlr;
        } while (!one);
 }
@@ -1006,25 +1029,18 @@ void interruptThread(java_lang_VMThread *thread)
 {
        threadobject *t = (threadobject*) thread;
 
-       monitorLockRecord *lr = t->waiting;
-       if (lr) {
-               pthread_mutex_lock(&lr->waitLock);
-               if (t->waiting == lr) {
-                       t->waiting = NULL;
-                       pthread_cond_signal(&lr->waitCond);
-               }
-               pthread_mutex_unlock(&lr->waitLock);
-               return;
-       }
-       
-       t->interrupted = 1;
+       t->interrupted = true;
+       pthread_mutex_lock(&t->waitLock);
+       if (t->isSleeping)
+               pthread_cond_signal(&t->waitCond);
+       pthread_mutex_unlock(&t->waitLock);
 }
 
 bool interruptedThread()
 {
        threadobject *t = (threadobject*) THREADOBJECT;
-       long intr = t->interrupted;
-       t->interrupted = 0;
+       bool intr = t->interrupted;
+       t->interrupted = false;
        return intr;
 }
 

diff --git a/threads/nativethread.h b/threads/nativethread.h
index 229414b447b23acd3fa34fbfaecdbdd7445fff11..db55fa4e041d6ff8b020277b804e5fc82379aaa6 100644 (file)
--- a/threads/nativethread.h
+++ b/threads/nativethread.h
@@ -25,8 +25,8 @@ typedef struct _monitorLockRecord {
        struct _monitorLockRecord *waiter, *incharge;
        bool waiting;
        sem_t queueSem;
-       pthread_mutex_t resolveLock, waitLock;
-       pthread_cond_t resolveWait, waitCond;
+       pthread_mutex_t resolveLock;
+       pthread_cond_t resolveWait;
 } monitorLockRecord;
 
 struct _lockRecordPool;
@@ -68,8 +68,9 @@ typedef struct _threadobject {
        nativethread info;
        ExecEnvironment ee;
 
-       long interrupted;
-       monitorLockRecord *waiting;
+       pthread_mutex_t waitLock;
+       pthread_cond_t waitCond;
+       bool interrupted, signaled, isSleeping;
 } threadobject;
 
 monitorLockRecord *monitorEnter(threadobject *, java_objectheader *);