[PATCH 17/32] posix: Rework pthread_join()

Sebastian Huber sebastian.huber at embedded-brains.de
Wed May 18 09:20:36 UTC 2016


Rework pthread_join() to use _Thread_Join().

Close #2402.
Update #2555.
Update #2626.
Close #2714.
---
 cpukit/posix/include/rtems/posix/pthreadimpl.h |  14 ---
 cpukit/posix/include/rtems/posix/threadsup.h   |   4 -
 cpukit/posix/src/pthread.c                     |  51 ++--------
 cpukit/posix/src/pthreadcreate.c               |   5 +-
 cpukit/posix/src/pthreaddetach.c               |  39 ++++----
 cpukit/posix/src/pthreadexit.c                 |  37 ++-----
 cpukit/posix/src/pthreadgetattrnp.c            |   6 ++
 cpukit/posix/src/pthreadjoin.c                 | 131 +++++++++++++------------
 cpukit/rtems/src/taskdelete.c                  |  10 +-
 cpukit/score/include/rtems/score/statesimpl.h  |   7 ++
 cpukit/score/include/rtems/score/thread.h      |  15 ++-
 cpukit/score/include/rtems/score/threadimpl.h  |  20 +++-
 cpukit/score/src/threadrestart.c               |  92 ++++++++++++++++-
 13 files changed, 243 insertions(+), 188 deletions(-)

diff --git a/cpukit/posix/include/rtems/posix/pthreadimpl.h b/cpukit/posix/include/rtems/posix/pthreadimpl.h
index 42f10b0..16b0163 100644
--- a/cpukit/posix/include/rtems/posix/pthreadimpl.h
+++ b/cpukit/posix/include/rtems/posix/pthreadimpl.h
@@ -35,8 +35,6 @@ extern "C" {
  */
 /**@{**/
 
-#define POSIX_THREAD_JOIN_TQ_OPERATIONS &_Thread_queue_Operations_FIFO
-
 /**
  * The following sets the minimum stack size for POSIX threads.
  */
@@ -211,18 +209,6 @@ RTEMS_INLINE_ROUTINE bool _POSIX_Threads_Is_null (
   return !the_pthread;
 }
 
-RTEMS_INLINE_ROUTINE Thread_Control *_POSIX_Threads_Join_dequeue(
-  POSIX_API_Control *api
-)
-{
-  return _Thread_queue_Dequeue(
-    &api->Join_List,
-    POSIX_THREAD_JOIN_TQ_OPERATIONS,
-    NULL,
-    0
-  );
-}
-
 /** @} */
 
 #ifdef __cplusplus
diff --git a/cpukit/posix/include/rtems/posix/threadsup.h b/cpukit/posix/include/rtems/posix/threadsup.h
index 8109921..3a7cfbc 100644
--- a/cpukit/posix/include/rtems/posix/threadsup.h
+++ b/cpukit/posix/include/rtems/posix/threadsup.h
@@ -47,10 +47,6 @@ typedef struct {
   Thread_Control         *thread;
   /** This is the POSIX threads attribute set. */
   pthread_attr_t          Attributes;
-  /** This indicates whether the thread is attached or detached. */
-  int                     detachstate;
-  /** This is the set of threads waiting for the thread to exit. */
-  Thread_queue_Control    Join_List;
   /** This is the thread's current scheduling policy. */
   int                     schedpolicy;
   /** This is the thread's current set of scheduling parameters. */
diff --git a/cpukit/posix/src/pthread.c b/cpukit/posix/src/pthread.c
index 5c5cff7..12c5ace 100644
--- a/cpukit/posix/src/pthread.c
+++ b/cpukit/posix/src/pthread.c
@@ -203,7 +203,6 @@ static bool _POSIX_Threads_Create_extension(
   /* XXX check all fields are touched */
   api->thread = created;
   _POSIX_Threads_Initialize_attributes( &api->Attributes );
-  api->detachstate = _POSIX_Threads_Default_attributes.detachstate;
   api->schedpolicy = _POSIX_Threads_Default_attributes.schedpolicy;
   api->schedparam  = _POSIX_Threads_Default_attributes.schedparam;
   api->schedparam.sched_priority =
@@ -231,8 +230,6 @@ static bool _POSIX_Threads_Create_extension(
     api->signals_unblocked = executing_api->signals_unblocked;
   }
 
-  _Thread_queue_Initialize( &api->Join_List );
-
   _Watchdog_Preinitialize( &api->Sporadic_timer, _Per_CPU_Get_by_index( 0 ) );
   _Watchdog_Initialize(
     &api->Sporadic_timer,
@@ -242,42 +239,13 @@ static bool _POSIX_Threads_Create_extension(
   return true;
 }
 
-static void _POSIX_Threads_Delete_extension(
-  Thread_Control *executing,
-  Thread_Control *deleted
-)
+static void _POSIX_Threads_Terminate_extension( Thread_Control *executing )
 {
   POSIX_API_Control *api;
-
-  api = deleted->API_Extensions[ THREAD_API_POSIX ];
-
-  _Thread_queue_Destroy( &api->Join_List );
-}
-
-static void _POSIX_Threads_Terminate_extension(
-  Thread_Control *executing
-)
-{
-  Thread_Control     *the_thread;
-  POSIX_API_Control  *api;
-  ISR_lock_Context    lock_context;
-  void              **value_ptr;
+  ISR_lock_Context   lock_context;
 
   api = executing->API_Extensions[ THREAD_API_POSIX ];
 
-  _Thread_Disable_dispatch();
-
-  /*
-   *  Wakeup all the tasks which joined with this one
-   */
-  value_ptr = (void **) executing->Wait.return_argument;
-
-  while ( ( the_thread = _POSIX_Threads_Join_dequeue( api ) ) ) {
-    *(void **)the_thread->Wait.return_argument = value_ptr;
-  }
-
-  _Thread_Enable_dispatch();
-
   _Thread_State_acquire( executing, &lock_context );
 
   if ( api->schedpolicy == SCHED_SPORADIC ) {
@@ -305,17 +273,10 @@ static void _POSIX_Threads_Exitted_extension(
 }
 
 User_extensions_Control _POSIX_Threads_User_extensions = {
-  { NULL, NULL },
-  { { NULL, NULL }, NULL },
-  { _POSIX_Threads_Create_extension,          /* create */
-    NULL,                                     /* start */
-    NULL,                                     /* restart */
-    _POSIX_Threads_Delete_extension,          /* delete */
-    NULL,                                     /* switch */
-    NULL,                                     /* begin */
-    _POSIX_Threads_Exitted_extension,         /* exitted */
-    NULL,                                     /* fatal */
-    _POSIX_Threads_Terminate_extension        /* terminate */
+  .Callouts = {
+    .thread_create    = _POSIX_Threads_Create_extension,
+    .thread_exitted   = _POSIX_Threads_Exitted_extension,
+    .thread_terminate = _POSIX_Threads_Terminate_extension
   }
 };
 
diff --git a/cpukit/posix/src/pthreadcreate.c b/cpukit/posix/src/pthreadcreate.c
index eedb80e..1fe3fe4 100644
--- a/cpukit/posix/src/pthreadcreate.c
+++ b/cpukit/posix/src/pthreadcreate.c
@@ -201,6 +201,10 @@ int pthread_create(
     return EAGAIN;
   }
 
+  if ( the_attr->detachstate == PTHREAD_CREATE_DETACHED ) {
+    the_thread->Life.state |= THREAD_LIFE_DETACHED;
+  }
+
 #if defined(RTEMS_SMP) && __RTEMS_HAVE_SYS_CPUSET_H__
   _ISR_lock_ISR_disable( &lock_context );
    status = _Scheduler_Set_affinity(
@@ -222,7 +226,6 @@ int pthread_create(
   api = the_thread->API_Extensions[ THREAD_API_POSIX ];
 
   _POSIX_Threads_Copy_attributes( &api->Attributes, the_attr );
-  api->detachstate = the_attr->detachstate;
   api->schedpolicy = schedpolicy;
   api->schedparam  = schedparam;
 
diff --git a/cpukit/posix/src/pthreaddetach.c b/cpukit/posix/src/pthreaddetach.c
index d8c6afb..fe2a590 100644
--- a/cpukit/posix/src/pthreaddetach.c
+++ b/cpukit/posix/src/pthreaddetach.c
@@ -9,6 +9,8 @@
  *  COPYRIGHT (c) 1989-2014.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Copyright (c) 2016 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.org/license/LICENSE.
@@ -21,37 +23,30 @@
 #include <pthread.h>
 #include <errno.h>
 
-#include <rtems/posix/pthreadimpl.h>
 #include <rtems/score/threadimpl.h>
 
 /**
  * 16.1.4 Detaching a Thread, P1003.1c/Draft 10, p. 149
  */
-int pthread_detach(
-  pthread_t   thread
-)
+int pthread_detach( pthread_t thread )
 {
-  Thread_Control          *the_thread;
-  POSIX_API_Control       *api;
-  Objects_Locations        location;
+  Thread_Control   *the_thread;
+  ISR_lock_Context  lock_context;
+  Per_CPU_Control  *cpu_self;
 
-  the_thread = _Thread_Get( thread, &location );
-  switch ( location ) {
+  the_thread = _Thread_Get_interrupt_disable( thread, &lock_context );
 
-    case OBJECTS_LOCAL:
+  if ( the_thread == NULL ) {
+    return ESRCH;
+  }
 
-      api = the_thread->API_Extensions[ THREAD_API_POSIX ];
-      api->detachstate = PTHREAD_CREATE_DETACHED;
-      api->Attributes.detachstate = PTHREAD_CREATE_DETACHED;
-      _Objects_Put( &the_thread->Object );
-      return 0;
+  _Thread_State_acquire( the_thread, &lock_context );
 
-#if defined(RTEMS_MULTIPROCESSING)
-    case OBJECTS_REMOTE:
-#endif
-    case OBJECTS_ERROR:
-      break;
-  }
+  the_thread->Life.state |= THREAD_LIFE_DETACHED;
+  _Thread_Clear_state_locked( the_thread, STATES_WAITING_FOR_JOIN_AT_EXIT );
 
-  return ESRCH;
+  cpu_self = _Thread_Dispatch_disable_critical( &lock_context );
+  _Thread_State_release( the_thread, &lock_context );
+  _Thread_Dispatch_enable( cpu_self );
+  return 0;
 }
diff --git a/cpukit/posix/src/pthreadexit.c b/cpukit/posix/src/pthreadexit.c
index 559e37c..3c4d3eb 100644
--- a/cpukit/posix/src/pthreadexit.c
+++ b/cpukit/posix/src/pthreadexit.c
@@ -31,47 +31,24 @@ void _POSIX_Thread_Exit(
   void           *value_ptr
 )
 {
-  Thread_Control    *executing;
-  Thread_Control    *unblocked;
-  POSIX_API_Control *api;
-
-  api = the_thread->API_Extensions[ THREAD_API_POSIX ];
+  Thread_Control  *executing;
+  Per_CPU_Control *cpu_self;
 
   _Assert( _Debug_Is_thread_dispatching_allowed() );
 
-  _Thread_Disable_dispatch();
-
-  the_thread->Wait.return_argument = value_ptr;
-
-  /*
-   * Process join
-   */
-  if ( api->detachstate == PTHREAD_CREATE_JOINABLE ) {
-    unblocked = _POSIX_Threads_Join_dequeue( api );
-    if ( unblocked ) {
-      do {
-        *(void **)unblocked->Wait.return_argument = value_ptr;
-      } while ( ( unblocked = _POSIX_Threads_Join_dequeue( api ) ) );
-    } else {
-      _Thread_Set_state( the_thread, STATES_WAITING_FOR_JOIN_AT_EXIT );
-      _Thread_Enable_dispatch();
-      /* now waiting for thread to arrive */
-      _Thread_Disable_dispatch();
-    }
-  }
-
-  executing = _Thread_Executing;
+  cpu_self = _Thread_Dispatch_disable();
+  executing = _Per_CPU_Get_executing( cpu_self );
 
   /*
    *  Now shut down the thread
    */
   if ( the_thread == executing ) {
-    _Thread_Exit( executing );
+    _Thread_Exit( executing, THREAD_LIFE_TERMINATING, value_ptr );
   } else {
-    _Thread_Close( the_thread, executing );
+    _Thread_Cancel( the_thread, executing, value_ptr );
   }
 
-  _Thread_Enable_dispatch();
+  _Thread_Dispatch_enable( cpu_self );
 }
 
 void pthread_exit(
diff --git a/cpukit/posix/src/pthreadgetattrnp.c b/cpukit/posix/src/pthreadgetattrnp.c
index 57c5318..30cee97 100644
--- a/cpukit/posix/src/pthreadgetattrnp.c
+++ b/cpukit/posix/src/pthreadgetattrnp.c
@@ -49,6 +49,12 @@ int pthread_getattr_np(
   api = the_thread->API_Extensions[ THREAD_API_POSIX ];
   _POSIX_Threads_Copy_attributes( attr, &api->Attributes);
 
+  if ( _Thread_Is_joinable( the_thread ) ) {
+    attr->detachstate = PTHREAD_CREATE_JOINABLE;
+  } else {
+    attr->detachstate = PTHREAD_CREATE_DETACHED;
+  }
+
   _Thread_State_release( the_thread, &lock_context );
   return 0;
 }
diff --git a/cpukit/posix/src/pthreadjoin.c b/cpukit/posix/src/pthreadjoin.c
index 877c4bd..8950be2 100644
--- a/cpukit/posix/src/pthreadjoin.c
+++ b/cpukit/posix/src/pthreadjoin.c
@@ -11,6 +11,8 @@
  *  COPYRIGHT (c) 1989-2014.
  *  On-Line Applications Research Corporation (OAR).
  *
+ *  Copyright (c) 2016 embedded brains GmbH.
+ *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
  *  http://www.rtems.org/license/LICENSE.
@@ -23,74 +25,75 @@
 #include <pthread.h>
 #include <errno.h>
 
-#include <rtems/posix/pthreadimpl.h>
+#include <rtems/posix/threadsup.h>
 #include <rtems/score/threadimpl.h>
-#include <rtems/score/threadqimpl.h>
 #include <rtems/score/statesimpl.h>
 
-int pthread_join(
-  pthread_t   thread,
-  void      **value_ptr
-)
+static int _POSIX_Threads_Join( pthread_t thread, void **value_ptr )
 {
-  Thread_Control          *the_thread;
-  POSIX_API_Control       *api;
-  Objects_Locations        location;
-  void                    *return_pointer;
-  Thread_Control          *executing;
-
-on_EINTR:
-  the_thread = _Thread_Get( thread, &location );
-  switch ( location ) {
-
-    case OBJECTS_LOCAL:
-      api = the_thread->API_Extensions[ THREAD_API_POSIX ];
-
-      if ( api->detachstate == PTHREAD_CREATE_DETACHED ) {
-        _Objects_Put( &the_thread->Object );
-        return EINVAL;
-      }
-
-      executing = _Thread_Executing;
-
-      if ( executing == the_thread ) {
-        _Objects_Put( &the_thread->Object );
-        return EDEADLK;
-      }
-
-      /*
-       *  Put ourself on the threads join list
-       */
-
-      if ( the_thread->current_state == STATES_WAITING_FOR_JOIN_AT_EXIT ) {
-         return_pointer = the_thread->Wait.return_argument;
-         _Thread_Clear_state( the_thread, STATES_WAITING_FOR_JOIN_AT_EXIT );
-      } else {
-        executing->Wait.return_argument = &return_pointer;
-        _Thread_queue_Enqueue(
-          &api->Join_List,
-          POSIX_THREAD_JOIN_TQ_OPERATIONS,
-          executing,
-          STATES_WAITING_FOR_JOIN | STATES_INTERRUPTIBLE_BY_SIGNAL,
-          WATCHDOG_NO_TIMEOUT,
-          0
-        );
-      }
-      _Objects_Put( &the_thread->Object );
-
-      if ( executing->Wait.return_code == EINTR )
-        goto on_EINTR;
-
-      if ( value_ptr )
-        *value_ptr = return_pointer;
-      return 0;
-
-#if defined(RTEMS_MULTIPROCESSING)
-    case OBJECTS_REMOTE:
-#endif
-    case OBJECTS_ERROR:
-      break;
+  Thread_Control    *the_thread;
+  ISR_lock_Context   lock_context;
+  Per_CPU_Control   *cpu_self;
+  Thread_Control    *executing;
+  void              *value;
+
+  the_thread = _Thread_Get_interrupt_disable( thread, &lock_context );
+
+  if ( the_thread == NULL ) {
+    return ESRCH;
+  }
+
+  cpu_self = _Per_CPU_Get();
+  executing = _Per_CPU_Get_executing( cpu_self );
+
+  if ( executing == the_thread ) {
+    _ISR_lock_ISR_enable( &lock_context );
+    return EDEADLK;
+  }
+
+  _Thread_State_acquire_critical( the_thread, &lock_context );
+
+  if ( !_Thread_Is_joinable( the_thread ) ) {
+    _Thread_State_release( the_thread, &lock_context );
+    return EINVAL;
   }
 
-  return ESRCH;
+  if ( _States_Is_waiting_for_join_at_exit( the_thread->current_state ) ) {
+    value = the_thread->Life.exit_value;
+    _Thread_Clear_state_locked( the_thread, STATES_WAITING_FOR_JOIN_AT_EXIT );
+    _Thread_Dispatch_disable_with_CPU( cpu_self, &lock_context );
+    _Thread_State_release( the_thread, &lock_context );
+    _Thread_Dispatch_enable( cpu_self );
+  } else {
+    _Thread_Join(
+      the_thread,
+      STATES_INTERRUPTIBLE_BY_SIGNAL | STATES_WAITING_FOR_JOIN,
+      executing,
+      &lock_context
+    );
+
+    if ( executing->Wait.return_code != 0 ) {
+      _Assert( executing->Wait.return_code == EINTR );
+      return EINTR;
+    }
+
+    value = executing->Wait.return_argument;
+  }
+
+  if ( value_ptr != NULL ) {
+    *value_ptr = value;
+  }
+
+  return 0;
+}
+
+int pthread_join( pthread_t thread, void **value_ptr )
+{
+  int error;
+
+  do {
+    error = _POSIX_Threads_Join( thread, value_ptr );
+  } while ( error == EINTR );
+
+  return error;
 }
diff --git a/cpukit/rtems/src/taskdelete.c b/cpukit/rtems/src/taskdelete.c
index 5830793..2e8381c 100644
--- a/cpukit/rtems/src/taskdelete.c
+++ b/cpukit/rtems/src/taskdelete.c
@@ -52,7 +52,15 @@ rtems_status_code rtems_task_delete(
       executing = _Thread_Executing;
 
       if ( the_thread == executing ) {
-        _Thread_Exit( executing );
+        /*
+         * The Classic tasks are neither detached nor joinable.  In case of
+         * self deletion, they are detached, otherwise joinable by default.
+         */
+        _Thread_Exit(
+          executing,
+          THREAD_LIFE_TERMINATING | THREAD_LIFE_DETACHED,
+          NULL
+        );
       } else {
         _Thread_Close( the_thread, executing );
       }
diff --git a/cpukit/score/include/rtems/score/statesimpl.h b/cpukit/score/include/rtems/score/statesimpl.h
index a560329..54052e2 100644
--- a/cpukit/score/include/rtems/score/statesimpl.h
+++ b/cpukit/score/include/rtems/score/statesimpl.h
@@ -385,6 +385,13 @@ RTEMS_INLINE_ROUTINE bool _States_Is_waiting_for_period (
    return (the_states & STATES_WAITING_FOR_PERIOD);
 }
 
+RTEMS_INLINE_ROUTINE bool _States_Is_waiting_for_join_at_exit(
+  States_Control the_states
+)
+{
+   return ( the_states & STATES_WAITING_FOR_JOIN_AT_EXIT ) != 0;
+}
+
 /**
  * This function returns true if the task's state is set in
  * way that allows it to be interrupted by a signal.
diff --git a/cpukit/score/include/rtems/score/thread.h b/cpukit/score/include/rtems/score/thread.h
index 22e42bd..e4a9e27 100644
--- a/cpukit/score/include/rtems/score/thread.h
+++ b/cpukit/score/include/rtems/score/thread.h
@@ -522,7 +522,8 @@ typedef struct {
 typedef enum {
   THREAD_LIFE_PROTECTED = 0x1,
   THREAD_LIFE_RESTARTING = 0x2,
-  THREAD_LIFE_TERMINATING = 0x4
+  THREAD_LIFE_TERMINATING = 0x4,
+  THREAD_LIFE_DETACHED = 0x10
 } Thread_Life_state;
 
 /**
@@ -544,6 +545,18 @@ typedef struct {
    * @brief The count of pending life change requests.
    */
   uint32_t pending_life_change_requests;
+
+#if defined(RTEMS_POSIX_API)
+  /**
+   * @brief The thread exit value.
+   *
+   * It is,
+   * - the value passed to pthread_exit(), or
+   * - PTHREAD_CANCELED in case it is cancelled via pthread_cancel(), or
+   * - NULL.
+   */
+  void *exit_value;
+#endif
 } Thread_Life_control;
 
 #if defined(RTEMS_SMP)
diff --git a/cpukit/score/include/rtems/score/threadimpl.h b/cpukit/score/include/rtems/score/threadimpl.h
index 174f767..749d488 100644
--- a/cpukit/score/include/rtems/score/threadimpl.h
+++ b/cpukit/score/include/rtems/score/threadimpl.h
@@ -217,7 +217,11 @@ Thread_Life_state _Thread_Set_life_protection( Thread_Life_state state );
  */
 void _Thread_Kill_zombies( void );
 
-void _Thread_Exit( Thread_Control *executing );
+void _Thread_Exit(
+  Thread_Control    *executing,
+  Thread_Life_state  set,
+  void              *exit_value
+);
 
 void _Thread_Join(
   Thread_Control    *the_thread,
@@ -226,7 +230,11 @@ void _Thread_Join(
   ISR_lock_Context  *lock_context
 );
 
-void _Thread_Cancel( Thread_Control *the_thread, Thread_Control *executing );
+void _Thread_Cancel(
+  Thread_Control *the_thread,
+  Thread_Control *executing,
+  void           *exit_value
+);
 
 /**
  * @brief Closes the thread.
@@ -965,6 +973,14 @@ RTEMS_INLINE_ROUTINE bool _Thread_Is_life_changing(
     & ( THREAD_LIFE_RESTARTING | THREAD_LIFE_TERMINATING ) ) != 0;
 }
 
+RTEMS_INLINE_ROUTINE bool _Thread_Is_joinable(
+  const Thread_Control *the_thread
+)
+{
+  _Assert( _Thread_State_is_owner( the_thread ) );
+  return ( the_thread->Life.state & THREAD_LIFE_DETACHED ) == 0;
+}
+
 /**
  * @brief Returns true if the thread owns resources, and false otherwise.
  *
diff --git a/cpukit/score/src/threadrestart.c b/cpukit/score/src/threadrestart.c
index 4dda28b..cbaa522 100644
--- a/cpukit/score/src/threadrestart.c
+++ b/cpukit/score/src/threadrestart.c
@@ -88,17 +88,45 @@ static void _Thread_Raise_real_priority(
 
 typedef struct {
   ISR_lock_Context  Base;
+#if defined(RTEMS_POSIX_API)
+  void             *exit_value;
+#endif
 } Thread_Join_lock_context;
 
+#if defined(RTEMS_POSIX_API)
+static Thread_Control *_Thread_Join_flush_filter(
+  Thread_Control      *the_thread,
+  Thread_queue_Queue  *queue,
+  ISR_lock_Context    *lock_context
+)
+{
+  Thread_Join_lock_context *join_lock_context;
+
+  join_lock_context = (Thread_Join_lock_context *) lock_context;
+
+  the_thread->Wait.return_argument = join_lock_context->exit_value;
+
+  return the_thread;
+}
+#endif
+
 static void _Thread_Wake_up_joining_threads( Thread_Control *the_thread )
 {
   Thread_Join_lock_context join_lock_context;
 
+#if defined(RTEMS_POSIX_API)
+  join_lock_context.exit_value = the_thread->Life.exit_value;
+#endif
+
   _Thread_State_acquire( the_thread, &join_lock_context.Base );
   _Thread_queue_Flush_critical(
     &the_thread->Join_queue.Queue,
     THREAD_JOIN_TQ_OPERATIONS,
+#if defined(RTEMS_POSIX_API)
+    _Thread_Join_flush_filter,
+#else
     _Thread_queue_Flush_default_filter,
+#endif
     NULL,
     0,
     &join_lock_context.Base
@@ -256,6 +284,35 @@ static Thread_Life_state _Thread_Change_life_locked(
   return previous;
 }
 
+static Per_CPU_Control *_Thread_Wait_for_join(
+  Thread_Control  *executing,
+  Per_CPU_Control *cpu_self
+)
+{
+#if defined(RTEMS_POSIX_API)
+  ISR_lock_Context lock_context;
+
+  _Thread_State_acquire( executing, &lock_context );
+
+  if (
+    _Thread_Is_joinable( executing )
+      && _Thread_queue_Is_empty( &executing->Join_queue.Queue )
+  ) {
+    _Thread_Set_state_locked( executing, STATES_WAITING_FOR_JOIN_AT_EXIT );
+    _Thread_State_release( executing, &lock_context );
+    _Thread_Dispatch_enable( cpu_self );
+
+    /* Let other threads run */
+
+    cpu_self = _Thread_Dispatch_disable();
+  } else {
+    _Thread_State_release( executing, &lock_context );
+  }
+#endif
+
+  return cpu_self;
+}
+
 void _Thread_Life_action_handler(
   Thread_Control   *executing,
   Thread_Action    *action,
@@ -283,6 +340,8 @@ void _Thread_Life_action_handler(
   cpu_self = _Thread_Dispatch_disable();
 
   if ( _Thread_Is_life_terminating( previous_life_state ) ) {
+    cpu_self = _Thread_Wait_for_join( executing, cpu_self );
+
     _Thread_Make_zombie( executing );
 
     _Thread_Dispatch_enable( cpu_self );
@@ -384,6 +443,11 @@ void _Thread_Join(
   _Assert( the_thread != executing );
   _Assert( _Thread_State_is_owner( the_thread ) );
 
+#if defined(RTEMS_POSIX_API)
+  executing->Wait.return_code = 0;
+  executing->Wait.return_argument = NULL;
+#endif
+
   _Thread_queue_Enqueue_critical(
     &the_thread->Join_queue.Queue,
     THREAD_JOIN_TQ_OPERATIONS,
@@ -395,7 +459,21 @@ void _Thread_Join(
   );
 }
 
-void _Thread_Cancel( Thread_Control *the_thread, Thread_Control *executing )
+static void _Thread_Set_exit_value(
+  Thread_Control *the_thread,
+  void           *exit_value
+)
+{
+#if defined(RTEMS_POSIX_API)
+  the_thread->Life.exit_value = exit_value;
+#endif
+}
+
+void _Thread_Cancel(
+  Thread_Control *the_thread,
+  Thread_Control *executing,
+  void           *exit_value
+)
 {
   ISR_lock_Context   lock_context;
   Thread_Life_state  previous;
@@ -406,6 +484,7 @@ void _Thread_Cancel( Thread_Control *the_thread, Thread_Control *executing )
 
   _Thread_State_acquire( the_thread, &lock_context );
 
+  _Thread_Set_exit_value( the_thread, exit_value );
   previous = _Thread_Change_life_locked(
     the_thread,
     0,
@@ -447,10 +526,14 @@ void _Thread_Close( Thread_Control *the_thread, Thread_Control *executing )
     executing,
     &lock_context
   );
-  _Thread_Cancel( the_thread, executing );
+  _Thread_Cancel( the_thread, executing, NULL );
 }
 
-void _Thread_Exit( Thread_Control *executing )
+void _Thread_Exit(
+  Thread_Control    *executing,
+  Thread_Life_state  set,
+  void              *exit_value
+)
 {
   ISR_lock_Context lock_context;
 
@@ -463,10 +546,11 @@ void _Thread_Exit( Thread_Control *executing )
   );
 
   _Thread_State_acquire( executing, &lock_context );
+  _Thread_Set_exit_value( executing, exit_value );
   _Thread_Change_life_locked(
     executing,
     0,
-    THREAD_LIFE_TERMINATING,
+    set,
     THREAD_LIFE_PROTECTED
   );
   _Thread_State_release( executing, &lock_context );
-- 
1.8.4.5



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