diff options
Diffstat (limited to 'libjava/include/posix-threads.h')
| -rw-r--r-- | libjava/include/posix-threads.h | 217 |
1 files changed, 51 insertions, 166 deletions
diff --git a/libjava/include/posix-threads.h b/libjava/include/posix-threads.h index ac74ebe9309..22f6717e82d 100644 --- a/libjava/include/posix-threads.h +++ b/libjava/include/posix-threads.h @@ -20,81 +20,56 @@ details. */ #include <pthread.h> #include <sched.h> -#if defined (HAVE_PTHREAD_MUTEXATTR_SETTYPE) || defined (HAVE_PTHREAD_MUTEXATTR_SETKIND_NP) -# define HAVE_RECURSIVE_MUTEX 1 -#endif - - // // Typedefs. // -typedef pthread_cond_t _Jv_ConditionVariable_t; - -#if defined (PTHREAD_MUTEX_HAVE_M_COUNT) || defined (PTHREAD_MUTEX_HAVE___M_COUNT) +typedef struct _Jv_Thread_t +{ + // Flag values are defined in implementation. + int flags; -// On Linux we use implementation details of mutexes in order to get -// faster results. -typedef pthread_mutex_t _Jv_Mutex_t; + // Actual thread id. + pthread_t thread; + + // Java Thread object. + java::lang::Thread *thread_obj; + + // Condition variable and corresponding mutex, used to implement the + // interruptable wait/notify mechanism. + pthread_cond_t wait_cond; + pthread_mutex_t wait_mutex; + + // Next thread for Condition Variable wait-list chain. + _Jv_Thread_t *next; + +} _Jv_Thread_t; -#else /* LINUX_THREADS */ +typedef void _Jv_ThreadStartFunc (java::lang::Thread *); -#define PTHREAD_MUTEX_IS_STRUCT +// Condition Variables used to implement wait/notify/sleep/interrupt. typedef struct { - // Mutex used when locking this structure transiently. - pthread_mutex_t mutex; -#ifndef HAVE_RECURSIVE_MUTEX - // Some systems do not have recursive mutexes, so we must simulate - // them. Solaris is one such system. - - // Mutex the thread holds the entire time this mutex is held. This - // is used to make condition variables work properly. - pthread_mutex_t mutex2; - // Condition variable used when waiting for this lock. - pthread_cond_t cond; - // Thread holding this mutex. If COUNT is 0, no thread is holding. - pthread_t thread; -#endif /* HAVE_RECURSIVE_MUTEX */ - - // Number of times mutex is held. If 0, the lock is not held. We - // do this even if we have a native recursive mutex so that we can - // keep track of whether the lock is held; this lets us do error - // checking. FIXME it would be nice to optimize this; on some - // systems we could do so by relying on implementation details of - // recursive mutexes. - int count; -} _Jv_Mutex_t; + // Linked list of Threads that are waiting to be notified. + _Jv_Thread_t *first; -#endif +} _Jv_ConditionVariable_t; typedef struct { - // Flag values are defined in implementation. - int flags; - - // Actual thread id. - pthread_t thread; -} _Jv_Thread_t; -typedef void _Jv_ThreadStartFunc (java::lang::Thread *); + // For compatibility, simplicity, and correctness, we do not use the native + // pthreads recursive mutex implementation, but simulate them instead. + // Mutex the thread holds the entire time this mutex is held. + pthread_mutex_t mutex; -// This convenience function is used to return the POSIX mutex -// corresponding to our mutex. -inline pthread_mutex_t * -_Jv_PthreadGetMutex (_Jv_Mutex_t *mu) -{ -#if ! defined (PTHREAD_MUTEX_IS_STRUCT) - return mu; -#elif defined (HAVE_RECURSIVE_MUTEX) - return &mu->mutex; -#else - return &mu->mutex2; -#endif -} + // Thread holding this mutex. + pthread_t owner; -#include <stdio.h> + // Number of times mutex is held (lock depth). If 0, the lock is not held. + int count; +} _Jv_Mutex_t; // This is a convenience function used only by the pthreads thread // implementation. This is slow, but that's too bad -- we need to do @@ -104,95 +79,44 @@ _Jv_PthreadGetMutex (_Jv_Mutex_t *mu) inline int _Jv_PthreadCheckMonitor (_Jv_Mutex_t *mu) { - pthread_mutex_t *pmu; -#ifdef HAVE_RECURSIVE_MUTEX - pmu = _Jv_PthreadGetMutex (mu); - // See if the mutex is locked by this thread. - if (pthread_mutex_trylock (pmu)) - return 1; - -#if defined (PTHREAD_MUTEX_HAVE_M_COUNT) - // On Linux we exploit knowledge of the implementation. - int r = pmu->m_count == 1; -#elif defined (PTHREAD_MUTEX_HAVE___M_COUNT) - // In glibc 2.1, the first time the mutex is grabbed __m_count is - // set to 0 and __m_owner is set to pthread_self(). - int r = ! pmu->__m_count; -#else - int r = mu->count == 0; -#endif - -#else /* HAVE_RECURSIVE_MUTEX */ - // In this case we must lock our structure and then see if this - // thread owns the mutex. - pmu = &mu->mutex; - if (pthread_mutex_lock (pmu)) - return 1; - - int r = mu->thread != pthread_self () || mu->count == 0; -#endif /* HAVE_RECURSIVE_MUTEX */ - - pthread_mutex_unlock (pmu); - return r; + pthread_t self = pthread_self(); + if (mu->owner == self) + return 0; + else return 1; } // // Condition variables. // -inline void -_Jv_CondInit (_Jv_ConditionVariable_t *cv) -{ - pthread_cond_init (cv, 0); -} - -#ifndef LINUX_THREADS - -// pthread_cond_destroy does nothing on Linux and it is a win to avoid -// defining this macro. - -#define _Jv_HaveCondDestroy - -inline void -_Jv_CondDestroy (_Jv_ConditionVariable_t *cv) -{ - pthread_cond_destroy (cv); -} - -#endif /* LINUX_THREADS */ - int _Jv_CondWait (_Jv_ConditionVariable_t *cv, _Jv_Mutex_t *mu, jlong millis, jint nanos); + +int _Jv_CondNotify (_Jv_ConditionVariable_t *cv, _Jv_Mutex_t *mu); -inline int -_Jv_CondNotify (_Jv_ConditionVariable_t *cv, _Jv_Mutex_t *mu) -{ - return _Jv_PthreadCheckMonitor (mu) || pthread_cond_signal (cv); -} +int _Jv_CondNotifyAll (_Jv_ConditionVariable_t *cv, _Jv_Mutex_t *mu); -inline int -_Jv_CondNotifyAll (_Jv_ConditionVariable_t *cv, _Jv_Mutex_t *mu) +inline void +_Jv_CondInit (_Jv_ConditionVariable_t *cv) { - return _Jv_PthreadCheckMonitor (mu) || pthread_cond_broadcast (cv); + cv->first = NULL; } - // // Mutexes. // -#ifdef RECURSIVE_MUTEX_IS_DEFAULT inline void _Jv_MutexInit (_Jv_Mutex_t *mu) { - pthread_mutex_init (_Jv_PthreadGetMutex (mu), NULL); -#ifdef PTHREAD_MUTEX_IS_STRUCT + pthread_mutex_init (&mu->mutex, NULL); + mu->count = 0; -#endif + mu->owner = 0; } -#else -void _Jv_MutexInit (_Jv_Mutex_t *mu); -#endif + +int _Jv_MutexLock (_Jv_Mutex_t *mu); +int _Jv_MutexUnlock (_Jv_Mutex_t *mu); #ifndef LINUX_THREADS @@ -201,53 +125,14 @@ void _Jv_MutexInit (_Jv_Mutex_t *mu); #define _Jv_HaveMutexDestroy -#ifdef HAVE_RECURSIVE_MUTEX - -inline void +inline void _Jv_MutexDestroy (_Jv_Mutex_t *mu) { - pthread_mutex_destroy (_Jv_PthreadGetMutex (mu)); + pthread_mutex_destroy (&mu->mutex); } -#else /* HAVE_RECURSIVE_MUTEX */ - -extern void _Jv_MutexDestroy (_Jv_Mutex_t *mu); - -#endif /* HAVE_RECURSIVE_MUTEX */ #endif /* LINUX_THREADS */ -#ifdef HAVE_RECURSIVE_MUTEX - -inline int -_Jv_MutexLock (_Jv_Mutex_t *mu) -{ - int r = pthread_mutex_lock (_Jv_PthreadGetMutex (mu)); -#ifdef PTHREAD_MUTEX_IS_STRUCT - if (! r) - ++mu->count; -#endif - return r; -} - -inline int -_Jv_MutexUnlock (_Jv_Mutex_t *mu) -{ - int r = pthread_mutex_unlock (_Jv_PthreadGetMutex (mu)); -#ifdef PTHREAD_MUTEX_IS_STRUCT - if (! r) - --mu->count; -#endif - return r; -} - -#else /* HAVE_RECURSIVE_MUTEX */ - -extern int _Jv_MutexLock (_Jv_Mutex_t *mu); -extern int _Jv_MutexUnlock (_Jv_Mutex_t *mu); - -#endif /* HAVE_RECURSIVE_MUTEX */ - - // // Thread creation and manipulation. // |
