summaryrefslogtreecommitdiff
path: root/libpthread/sysdeps/generic/pt-barrier-wait.c
diff options
context:
space:
mode:
Diffstat (limited to 'libpthread/sysdeps/generic/pt-barrier-wait.c')
-rw-r--r--libpthread/sysdeps/generic/pt-barrier-wait.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/libpthread/sysdeps/generic/pt-barrier-wait.c b/libpthread/sysdeps/generic/pt-barrier-wait.c
new file mode 100644
index 00000000..f1de250a
--- /dev/null
+++ b/libpthread/sysdeps/generic/pt-barrier-wait.c
@@ -0,0 +1,61 @@
+/* pthread_barrier_wait. Generic version.
+ Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <pthread.h>
+#include <assert.h>
+
+#include <pt-internal.h>
+
+int
+pthread_barrier_wait (pthread_barrier_t *barrier)
+{
+ __pthread_spin_lock (&barrier->lock);
+ if (-- barrier->pending == 0)
+ {
+ barrier->pending = barrier->count;
+
+ if (barrier->count > 1)
+ {
+ struct __pthread *wakeup;
+
+ wakeup = barrier->queue;
+ barrier->queue = NULL;
+ __pthread_spin_unlock (&barrier->lock);
+
+ /* We can safely walk the list of waiting threads without
+ holding the lock since it is decoupled from the barrier
+ variable now. */
+ __pthread_dequeuing_iterate (wakeup, wakeup)
+ __pthread_wakeup (wakeup);
+ }
+
+ return PTHREAD_BARRIER_SERIAL_THREAD;
+ }
+ else
+ {
+ struct __pthread *self = _pthread_self ();
+
+ /* Add ourselves to the list of waiters. */
+ __pthread_enqueue (&barrier->queue, self);
+ __pthread_spin_unlock (&barrier->lock);
+
+ __pthread_block (self);
+ return 0;
+ }
+}