diff options
Diffstat (limited to 'linuxthreads/condvar.c')
| -rw-r--r-- | linuxthreads/condvar.c | 341 |
1 files changed, 0 insertions, 341 deletions
diff --git a/linuxthreads/condvar.c b/linuxthreads/condvar.c deleted file mode 100644 index 6ab95b88ae..0000000000 --- a/linuxthreads/condvar.c +++ /dev/null @@ -1,341 +0,0 @@ -/* Linuxthreads - a simple clone()-based implementation of Posix */ -/* threads for Linux. */ -/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ -/* and Pavel Krauz (krauz@fsid.cvut.cz). */ -/* */ -/* This program is free software; you can redistribute it and/or */ -/* modify it under the terms of the GNU Library General Public License */ -/* as published by the Free Software Foundation; either version 2 */ -/* of the License, or (at your option) any later version. */ -/* */ -/* This program is distributed in the hope that it will be useful, */ -/* but WITHOUT ANY WARRANTY; without even the implied warranty of */ -/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ -/* GNU Library General Public License for more details. */ - -/* Condition variables */ - -#include <errno.h> -#include <sched.h> -#include <stddef.h> -#include <sys/time.h> -#include "pthread.h" -#include "internals.h" -#include "spinlock.h" -#include "queue.h" -#include "restart.h" -#include <shlib-compat.h> - -int __pthread_cond_init(pthread_cond_t *cond, - const pthread_condattr_t *cond_attr) -{ - __pthread_init_lock(&cond->__c_lock); - cond->__c_waiting = NULL; - return 0; -} -versioned_symbol (libpthread, __pthread_cond_init, pthread_cond_init, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_init, __old_pthread_cond_init) -compat_symbol (libpthread, __old_pthread_cond_init, pthread_cond_init, - GLIBC_2_0); -#endif - -int __pthread_cond_destroy(pthread_cond_t *cond) -{ - if (cond->__c_waiting != NULL) return EBUSY; - return 0; -} -versioned_symbol (libpthread, __pthread_cond_destroy, pthread_cond_destroy, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_destroy, __old_pthread_cond_destroy) -compat_symbol (libpthread, __old_pthread_cond_destroy, pthread_cond_destroy, - GLIBC_2_0); -#endif - -/* Function called by pthread_cancel to remove the thread from - waiting on a condition variable queue. */ - -static int cond_extricate_func(void *obj, pthread_descr th) -{ - volatile pthread_descr self = thread_self(); - pthread_cond_t *cond = obj; - int did_remove = 0; - - __pthread_lock(&cond->__c_lock, self); - did_remove = remove_from_queue(&cond->__c_waiting, th); - __pthread_unlock(&cond->__c_lock); - - return did_remove; -} - -int __pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex) -{ - volatile pthread_descr self = thread_self(); - pthread_extricate_if extr; - int already_canceled = 0; - int spurious_wakeup_count; - - /* Check whether the mutex is locked and owned by this thread. */ - if (mutex->__m_kind != PTHREAD_MUTEX_TIMED_NP - && mutex->__m_kind != PTHREAD_MUTEX_ADAPTIVE_NP - && mutex->__m_owner != self) - return EINVAL; - - /* Set up extrication interface */ - extr.pu_object = cond; - extr.pu_extricate_func = cond_extricate_func; - - /* Register extrication interface */ - THREAD_SETMEM(self, p_condvar_avail, 0); - __pthread_set_own_extricate_if(self, &extr); - - /* Atomically enqueue thread for waiting, but only if it is not - canceled. If the thread is canceled, then it will fall through the - suspend call below, and then call pthread_exit without - having to worry about whether it is still on the condition variable queue. - This depends on pthread_cancel setting p_canceled before calling the - extricate function. */ - - __pthread_lock(&cond->__c_lock, self); - if (!(THREAD_GETMEM(self, p_canceled) - && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE)) - enqueue(&cond->__c_waiting, self); - else - already_canceled = 1; - __pthread_unlock(&cond->__c_lock); - - if (already_canceled) { - __pthread_set_own_extricate_if(self, 0); - __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME); - } - - pthread_mutex_unlock(mutex); - - spurious_wakeup_count = 0; - while (1) - { - suspend(self); - if (THREAD_GETMEM(self, p_condvar_avail) == 0 - && (THREAD_GETMEM(self, p_woken_by_cancel) == 0 - || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE)) - { - /* Count resumes that don't belong to us. */ - spurious_wakeup_count++; - continue; - } - break; - } - - __pthread_set_own_extricate_if(self, 0); - - /* Check for cancellation again, to provide correct cancellation - point behavior */ - - if (THREAD_GETMEM(self, p_woken_by_cancel) - && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) { - THREAD_SETMEM(self, p_woken_by_cancel, 0); - pthread_mutex_lock(mutex); - __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME); - } - - /* Put back any resumes we caught that don't belong to us. */ - while (spurious_wakeup_count--) - restart(self); - - pthread_mutex_lock(mutex); - return 0; -} -versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_wait, __old_pthread_cond_wait) -compat_symbol (libpthread, __old_pthread_cond_wait, pthread_cond_wait, - GLIBC_2_0); -#endif - -static int -pthread_cond_timedwait_relative(pthread_cond_t *cond, - pthread_mutex_t *mutex, - const struct timespec * abstime) -{ - volatile pthread_descr self = thread_self(); - int already_canceled = 0; - pthread_extricate_if extr; - int spurious_wakeup_count; - - /* Check whether the mutex is locked and owned by this thread. */ - if (mutex->__m_kind != PTHREAD_MUTEX_TIMED_NP - && mutex->__m_kind != PTHREAD_MUTEX_ADAPTIVE_NP - && mutex->__m_owner != self) - return EINVAL; - - /* Set up extrication interface */ - extr.pu_object = cond; - extr.pu_extricate_func = cond_extricate_func; - - /* Register extrication interface */ - THREAD_SETMEM(self, p_condvar_avail, 0); - __pthread_set_own_extricate_if(self, &extr); - - /* Enqueue to wait on the condition and check for cancellation. */ - __pthread_lock(&cond->__c_lock, self); - if (!(THREAD_GETMEM(self, p_canceled) - && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE)) - enqueue(&cond->__c_waiting, self); - else - already_canceled = 1; - __pthread_unlock(&cond->__c_lock); - - if (already_canceled) { - __pthread_set_own_extricate_if(self, 0); - __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME); - } - - pthread_mutex_unlock(mutex); - - spurious_wakeup_count = 0; - while (1) - { - if (!timedsuspend(self, abstime)) { - int was_on_queue; - - /* __pthread_lock will queue back any spurious restarts that - may happen to it. */ - - __pthread_lock(&cond->__c_lock, self); - was_on_queue = remove_from_queue(&cond->__c_waiting, self); - __pthread_unlock(&cond->__c_lock); - - if (was_on_queue) { - __pthread_set_own_extricate_if(self, 0); - pthread_mutex_lock(mutex); - return ETIMEDOUT; - } - - /* Eat the outstanding restart() from the signaller */ - suspend(self); - } - - if (THREAD_GETMEM(self, p_condvar_avail) == 0 - && (THREAD_GETMEM(self, p_woken_by_cancel) == 0 - || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE)) - { - /* Count resumes that don't belong to us. */ - spurious_wakeup_count++; - continue; - } - break; - } - - __pthread_set_own_extricate_if(self, 0); - - /* The remaining logic is the same as in other cancellable waits, - such as pthread_join sem_wait or pthread_cond wait. */ - - if (THREAD_GETMEM(self, p_woken_by_cancel) - && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) { - THREAD_SETMEM(self, p_woken_by_cancel, 0); - pthread_mutex_lock(mutex); - __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME); - } - - /* Put back any resumes we caught that don't belong to us. */ - while (spurious_wakeup_count--) - restart(self); - - pthread_mutex_lock(mutex); - return 0; -} - -int __pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, - const struct timespec * abstime) -{ - /* Indirect call through pointer! */ - return pthread_cond_timedwait_relative(cond, mutex, abstime); -} -versioned_symbol (libpthread, __pthread_cond_timedwait, pthread_cond_timedwait, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_timedwait, __old_pthread_cond_timedwait) -compat_symbol (libpthread, __old_pthread_cond_timedwait, - pthread_cond_timedwait, GLIBC_2_0); -#endif - -int __pthread_cond_signal(pthread_cond_t *cond) -{ - pthread_descr th; - - __pthread_lock(&cond->__c_lock, NULL); - th = dequeue(&cond->__c_waiting); - __pthread_unlock(&cond->__c_lock); - if (th != NULL) { - th->p_condvar_avail = 1; - WRITE_MEMORY_BARRIER(); - restart(th); - } - return 0; -} -versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_signal, __old_pthread_cond_signal) -compat_symbol (libpthread, __old_pthread_cond_signal, pthread_cond_signal, - GLIBC_2_0); -#endif - -int __pthread_cond_broadcast(pthread_cond_t *cond) -{ - pthread_descr tosignal, th; - - __pthread_lock(&cond->__c_lock, NULL); - /* Copy the current state of the waiting queue and empty it */ - tosignal = cond->__c_waiting; - cond->__c_waiting = NULL; - __pthread_unlock(&cond->__c_lock); - /* Now signal each process in the queue */ - while ((th = dequeue(&tosignal)) != NULL) { - th->p_condvar_avail = 1; - WRITE_MEMORY_BARRIER(); - restart(th); - } - return 0; -} -versioned_symbol (libpthread, __pthread_cond_broadcast, pthread_cond_broadcast, - GLIBC_2_3_2); -#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2) -strong_alias (__pthread_cond_broadcast, __old_pthread_cond_broadcast) -compat_symbol (libpthread, __old_pthread_cond_broadcast, - pthread_cond_broadcast, GLIBC_2_0); -#endif - -int __pthread_condattr_init(pthread_condattr_t *attr) -{ - return 0; -} -strong_alias (__pthread_condattr_init, pthread_condattr_init) - -int __pthread_condattr_destroy(pthread_condattr_t *attr) -{ - return 0; -} -strong_alias (__pthread_condattr_destroy, pthread_condattr_destroy) - -int pthread_condattr_getpshared (const pthread_condattr_t *attr, int *pshared) -{ - *pshared = PTHREAD_PROCESS_PRIVATE; - return 0; -} - -int pthread_condattr_setpshared (pthread_condattr_t *attr, int pshared) -{ - if (pshared != PTHREAD_PROCESS_PRIVATE && pshared != PTHREAD_PROCESS_SHARED) - return EINVAL; - - /* For now it is not possible to shared a conditional variable. */ - if (pshared != PTHREAD_PROCESS_PRIVATE) - return ENOSYS; - - return 0; -} |