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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) {