-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <stdlib.h>
-#include "atomic.h"
+#include <atomic.h>
#include "pthreadP.h"
static void
cleanup (void *arg)
{
- *(void **) arg = NULL;
+ /* If we already changed the waiter ID, reset it. The call cannot
+ fail for any reason but the thread not having done that yet so
+ there is no reason for a loop. */
+ (void) atomic_compare_and_exchange_bool_acq ((struct pthread **) arg, NULL,
+ THREAD_SELF);
}
int
-pthread_join (pthread_t threadid, void **thread_return)
+pthread_join (
+ pthread_t threadid,
+ void **thread_return)
{
- struct pthread *self;
struct pthread *pd = (struct pthread *) threadid;
/* Make sure the descriptor is valid. */
/* We cannot wait for the thread. */
return EINVAL;
- self = THREAD_SELF;
- if (pd == self
- || (self->joinid == pd
- && (pd->cancelhandling
- & (CANCELING_BITMASK | CANCELED_BITMASK | EXITING_BITMASK
- | TERMINATED_BITMASK)) == 0))
+ struct pthread *self = THREAD_SELF;
+ int result = 0;
+
+ /* During the wait we change to asynchronous cancellation. If we
+ are canceled the thread we are waiting for must be marked as
+ un-wait-ed for again. */
+ pthread_cleanup_push (cleanup, &pd->joinid);
+
+ /* Switch to asynchronous cancellation. */
+ int oldtype = CANCEL_ASYNC ();
+
+ if ((pd == self
+ || (self->joinid == pd
+ && (pd->cancelhandling
+ & (CANCELING_BITMASK | CANCELED_BITMASK | EXITING_BITMASK
+ | TERMINATED_BITMASK)) == 0))
+ && !CANCEL_ENABLED_AND_CANCELED (self->cancelhandling))
/* This is a deadlock situation. The threads are waiting for each
other to finish. Note that this is a "may" error. To be 100%
sure we catch this error we would have to lock the data
two threads are really caught in this situation they will
deadlock. It is the programmer's problem to figure this
out. */
- return EDEADLK;
-
+ result = EDEADLK;
/* Wait for the thread to finish. If it is already locked something
is wrong. There can only be one waiter. */
- if (__builtin_expect (atomic_compare_and_exchange_bool_acq (&pd->joinid,
- self,
- NULL), 0))
+ else if (__builtin_expect (atomic_compare_and_exchange_bool_acq (&pd->joinid,
+ self,
+ NULL), 0))
/* There is already somebody waiting for the thread. */
- return EINVAL;
-
-
- /* During the wait we change to asynchronous cancellation. If we
- are cancelled the thread we are waiting for must be marked as
- un-wait-ed for again. */
- pthread_cleanup_push (cleanup, &pd->joinid);
-
- /* Switch to asynchronous cancellation. */
- int oldtype = CANCEL_ASYNC ();
-
-
- /* Wait for the child. */
- lll_wait_tid (pd->tid);
+ result = EINVAL;
+ else
+ /* Wait for the child. */
+ lll_wait_tid (pd->tid);
/* Restore cancellation mode. */
pthread_cleanup_pop (0);
- /* We mark the thread as terminated and as joined. */
- pd->tid = -1;
+ if (__builtin_expect (result == 0, 1))
+ {
+ /* We mark the thread as terminated and as joined. */
+ pd->tid = -1;
- /* Store the return value if the caller is interested. */
- if (thread_return != NULL)
- *thread_return = pd->result;
+ /* Store the return value if the caller is interested. */
+ if (thread_return != NULL)
+ *thread_return = pd->result;
- /* Free the TCB. */
- __free_tcb (pd);
+ /* Free the TCB. */
+ __free_tcb (pd);
+ }
- return 0;
+ return result;
}