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diff --git a/REORG.TODO/nptl/pthread_join.c b/REORG.TODO/nptl/pthread_join.c
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+/* Copyright (C) 2002-2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include <atomic.h>
+#include "pthreadP.h"
+
+#include <stap-probe.h>
+
+
+static void
+cleanup (void *arg)
+{
+ /* 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)
+{
+ struct pthread *pd = (struct pthread *) threadid;
+
+ /* Make sure the descriptor is valid. */
+ if (INVALID_NOT_TERMINATED_TD_P (pd))
+ /* Not a valid thread handle. */
+ return ESRCH;
+
+ /* Is the thread joinable?. */
+ if (IS_DETACHED (pd))
+ /* We cannot wait for the thread. */
+ return EINVAL;
+
+ struct pthread *self = THREAD_SELF;
+ int result = 0;
+
+ LIBC_PROBE (pthread_join, 1, threadid);
+
+ /* 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
+ structures but it is not necessary. In the unlikely case that
+ two threads are really caught in this situation they will
+ deadlock. It is the programmer's problem to figure this
+ out. */
+ result = EDEADLK;
+ /* Wait for the thread to finish. If it is already locked something
+ is wrong. There can only be one waiter. */
+ else if (__builtin_expect (atomic_compare_and_exchange_bool_acq (&pd->joinid,
+ self,
+ NULL), 0))
+ /* There is already somebody waiting for the thread. */
+ result = EINVAL;
+ else
+ /* Wait for the child. */
+ lll_wait_tid (pd->tid);
+
+
+ /* Restore cancellation mode. */
+ CANCEL_RESET (oldtype);
+
+ /* Remove the handler. */
+ pthread_cleanup_pop (0);
+
+
+ if (__glibc_likely (result == 0))
+ {
+ /* 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;
+
+
+ /* Free the TCB. */
+ __free_tcb (pd);
+ }
+
+ LIBC_PROBE (pthread_join_ret, 3, threadid, result, pd->result);
+
+ return result;
+}