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-rw-r--r--linuxthreads/internals.h2
-rw-r--r--linuxthreads/manager.c33
-rw-r--r--linuxthreads/mutex.c91
-rw-r--r--linuxthreads/pthread.c29
4 files changed, 95 insertions, 60 deletions
diff --git a/linuxthreads/internals.h b/linuxthreads/internals.h
index c56829684e..ab6b66a857 100644
--- a/linuxthreads/internals.h
+++ b/linuxthreads/internals.h
@@ -288,7 +288,7 @@ int __pthread_manager(void *reqfd);
void __pthread_manager_sighandler(int sig);
void __pthread_reset_main_thread(void);
void __fresetlockfiles(void);
-
+void __pthread_manager_adjust_prio(int thread_prio);
/* Prototypes for the function without cancelation support when the
normal version has it. */
diff --git a/linuxthreads/manager.c b/linuxthreads/manager.c
index e7de399cde..c9625327c1 100644
--- a/linuxthreads/manager.c
+++ b/linuxthreads/manager.c
@@ -93,6 +93,8 @@ int __pthread_manager(void *arg)
sigfillset(&mask);
sigdelset(&mask, PTHREAD_SIG_RESTART);
sigprocmask(SIG_SETMASK, &mask, NULL);
+ /* Raise our priority to match that of main thread */
+ __pthread_manager_adjust_prio(__pthread_main_thread->p_priority);
/* Enter server loop */
while(1) {
FD_ZERO(&readfds);
@@ -276,6 +278,8 @@ static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
new_thread->p_start_args.start_routine = start_routine;
new_thread->p_start_args.arg = arg;
new_thread->p_start_args.mask = *mask;
+ /* Raise priority of thread manager if needed */
+ __pthread_manager_adjust_prio(new_thread->p_priority);
/* Do the cloning */
pid = __clone(pthread_start_thread, (void **) new_thread,
CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
@@ -390,10 +394,22 @@ static void pthread_reap_children(void)
}
}
-/* Free the resources of a thread */
+/* Try to free the resources of a thread when requested by pthread_join
+ or pthread_detach on a terminated thread. */
static void pthread_handle_free(pthread_descr th)
{
+ pthread_descr t;
+
+ /* Check that the thread th is still there -- pthread_reap_children
+ might have deallocated it already */
+ t = __pthread_main_thread;
+ do {
+ if (t == th) break;
+ t = t->p_nextlive;
+ } while (t != __pthread_main_thread);
+ if (t != th) return;
+
acquire(th->p_spinlock);
if (th->p_exited) {
release(th->p_spinlock);
@@ -455,3 +471,18 @@ void __pthread_manager_sighandler(int sig)
{
terminated_children = 1;
}
+
+/* Adjust priority of thread manager so that it always run at a priority
+ higher than all threads */
+
+void __pthread_manager_adjust_prio(int thread_prio)
+{
+ struct sched_param param;
+
+ if (thread_prio <= __pthread_manager_thread.p_priority) return;
+ param.sched_priority =
+ thread_prio < __sched_get_priority_max(SCHED_FIFO)
+ ? thread_prio + 1 : thread_prio;
+ __sched_setscheduler(__pthread_manager_thread.p_pid, SCHED_FIFO, &param);
+ __pthread_manager_thread.p_priority = thread_prio;
+}
diff --git a/linuxthreads/mutex.c b/linuxthreads/mutex.c
index d4ebcb827a..3b40ac04c5 100644
--- a/linuxthreads/mutex.c
+++ b/linuxthreads/mutex.c
@@ -91,47 +91,49 @@ int __pthread_mutex_lock(pthread_mutex_t * mutex)
{
pthread_descr self;
- while(1) {
- acquire(&mutex->m_spinlock);
- switch(mutex->m_kind) {
- case PTHREAD_MUTEX_FAST_NP:
- if (mutex->m_count == 0) {
- mutex->m_count = 1;
- release(&mutex->m_spinlock);
- return 0;
- }
- self = thread_self();
- break;
- case PTHREAD_MUTEX_RECURSIVE_NP:
- self = thread_self();
- if (mutex->m_count == 0 || mutex->m_owner == self) {
- mutex->m_count++;
- mutex->m_owner = self;
- release(&mutex->m_spinlock);
- return 0;
- }
- break;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
- self = thread_self();
- if (mutex->m_count == 0) {
- mutex->m_count = 1;
- mutex->m_owner = self;
- release(&mutex->m_spinlock);
- return 0;
- } else if (mutex->m_owner == self) {
- release(&mutex->m_spinlock);
- return EDEADLK;
- }
- break;
- default:
+ acquire(&mutex->m_spinlock);
+ switch(mutex->m_kind) {
+ case PTHREAD_MUTEX_FAST_NP:
+ if (mutex->m_count == 0) {
+ mutex->m_count = 1;
+ release(&mutex->m_spinlock);
+ return 0;
+ }
+ self = thread_self();
+ break;
+ case PTHREAD_MUTEX_RECURSIVE_NP:
+ self = thread_self();
+ if (mutex->m_count == 0 || mutex->m_owner == self) {
+ mutex->m_count++;
+ mutex->m_owner = self;
+ release(&mutex->m_spinlock);
+ return 0;
+ }
+ break;
+ case PTHREAD_MUTEX_ERRORCHECK_NP:
+ self = thread_self();
+ if (mutex->m_count == 0) {
+ mutex->m_count = 1;
+ mutex->m_owner = self;
release(&mutex->m_spinlock);
- return EINVAL;
+ return 0;
+ } else if (mutex->m_owner == self) {
+ release(&mutex->m_spinlock);
+ return EDEADLK;
}
- /* Suspend ourselves, then try again */
- enqueue(&mutex->m_waiting, self);
+ break;
+ default:
release(&mutex->m_spinlock);
- suspend(self); /* This is not a cancellation point */
+ return EINVAL;
}
+ /* Suspend ourselves */
+ enqueue(&mutex->m_waiting, self);
+ release(&mutex->m_spinlock);
+ suspend(self); /* This is not a cancellation point */
+ /* Now we own the mutex */
+ ASSERT(mutex->m_count == 1);
+ mutex->m_owner = self; /* for recursive and errorcheck mutexes */
+ return 0;
}
weak_alias (__pthread_mutex_lock, pthread_mutex_lock)
@@ -142,30 +144,33 @@ int __pthread_mutex_unlock(pthread_mutex_t * mutex)
acquire(&mutex->m_spinlock);
switch (mutex->m_kind) {
case PTHREAD_MUTEX_FAST_NP:
- mutex->m_count = 0;
break;
case PTHREAD_MUTEX_RECURSIVE_NP:
- mutex->m_count--;
- if (mutex->m_count > 0) {
+ if (mutex->m_count >= 2) {
+ mutex->m_count--;
release(&mutex->m_spinlock);
return 0;
}
- mutex->m_count = 0; /* so that excess unlocks do not break everything */
break;
case PTHREAD_MUTEX_ERRORCHECK_NP:
if (mutex->m_count == 0 || mutex->m_owner != thread_self()) {
release(&mutex->m_spinlock);
return EPERM;
}
- mutex->m_count = 0;
break;
default:
release(&mutex->m_spinlock);
return EINVAL;
}
th = dequeue(&mutex->m_waiting);
+ /* If no waiters, unlock the mutex */
+ if (th == NULL) mutex->m_count = 0;
release(&mutex->m_spinlock);
- if (th != NULL) restart(th);
+ /* If there is a waiter, restart it with the mutex still locked */
+ if (th != NULL) {
+ mutex->m_owner = NULL; /* we no longer own the mutex */
+ restart(th);
+ }
return 0;
}
weak_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
diff --git a/linuxthreads/pthread.c b/linuxthreads/pthread.c
index 9699b4ddcc..83d160622d 100644
--- a/linuxthreads/pthread.c
+++ b/linuxthreads/pthread.c
@@ -58,7 +58,8 @@ struct _pthread_descr_struct __pthread_initial_thread = {
};
/* Descriptor of the manager thread; none of this is used but the error
- variables and the address for identification. */
+ variables, the p_pid and p_priority fields,
+ and the address for identification. */
struct _pthread_descr_struct __pthread_manager_thread = {
NULL, /* pthread_descr p_nextlive */
@@ -108,10 +109,6 @@ int __pthread_manager_request = -1;
int __pthread_manager_reader;
-/* PID of thread manager */
-
-static int __pthread_manager_pid;
-
/* Limits of the thread manager stack */
char *__pthread_manager_thread_bos = NULL;
@@ -203,6 +200,7 @@ static void pthread_initialize(void)
static int pthread_initialize_manager(void)
{
int manager_pipe[2];
+ int pid;
/* If basic initialization not done yet (e.g. we're called from a
constructor run before our constructor), do it now */
@@ -217,20 +215,19 @@ static int pthread_initialize_manager(void)
free(__pthread_manager_thread_bos);
return -1;
}
- __pthread_manager_request = manager_pipe[1]; /* writing end */
- __pthread_manager_reader = manager_pipe[0]; /* reading end */
/* Start the thread manager */
- __pthread_manager_pid =
- __clone(__pthread_manager, (void **) __pthread_manager_thread_tos,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND,
- (void *)(long)manager_pipe[0]);
- if (__pthread_manager_pid == -1) {
+ pid = __clone(__pthread_manager, (void **) __pthread_manager_thread_tos,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND,
+ (void *)(long)manager_pipe[0]);
+ if (pid == -1) {
free(__pthread_manager_thread_bos);
__libc_close(manager_pipe[0]);
__libc_close(manager_pipe[1]);
- __pthread_manager_request = -1;
return -1;
}
+ __pthread_manager_request = manager_pipe[1]; /* writing end */
+ __pthread_manager_reader = manager_pipe[0]; /* reading end */
+ __pthread_manager_thread.p_pid = pid;
return 0;
}
@@ -319,6 +316,8 @@ int pthread_setschedparam(pthread_t thread, int policy,
}
th->p_priority = policy == SCHED_OTHER ? 0 : param->sched_priority;
release(&handle->h_spinlock);
+ if (__pthread_manager_request >= 0)
+ __pthread_manager_adjust_prio(th->p_priority);
return 0;
}
@@ -359,7 +358,7 @@ static void pthread_exit_process(int retcode, void *arg)
/* Main thread should accumulate times for thread manager and its
children, so that timings for main thread account for all threads. */
if (self == __pthread_main_thread)
- waitpid(__pthread_manager_pid, NULL, __WCLONE);
+ waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
}
}
@@ -392,7 +391,7 @@ static void pthread_handle_sigcancel(int sig)
/* Main thread should accumulate times for thread manager and its
children, so that timings for main thread account for all threads. */
if (self == __pthread_main_thread)
- waitpid(__pthread_manager_pid, NULL, __WCLONE);
+ waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
_exit(__pthread_exit_code);
}
if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 20:02:29 +0000