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Diffstat (limited to 'libpthread/nptl/sysdeps/pthread/pthread_cond_broadcast.c')
-rw-r--r--libpthread/nptl/sysdeps/pthread/pthread_cond_broadcast.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/pthread/pthread_cond_broadcast.c b/libpthread/nptl/sysdeps/pthread/pthread_cond_broadcast.c
new file mode 100644
index 000000000..5e7465774
--- /dev/null
+++ b/libpthread/nptl/sysdeps/pthread/pthread_cond_broadcast.c
@@ -0,0 +1,89 @@
+/* Copyright (C) 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
+
+ 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <endian.h>
+#include <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <pthread.h>
+#include <pthreadP.h>
+
+#include <bits/kernel-features.h>
+
+
+int
+__pthread_cond_broadcast (
+ pthread_cond_t *cond)
+{
+ int pshared = (cond->__data.__mutex == (void *) ~0l)
+ ? LLL_SHARED : LLL_PRIVATE;
+ /* Make sure we are alone. */
+ lll_lock (cond->__data.__lock, pshared);
+
+ /* Are there any waiters to be woken? */
+ if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
+ {
+ /* Yes. Mark them all as woken. */
+ cond->__data.__wakeup_seq = cond->__data.__total_seq;
+ cond->__data.__woken_seq = cond->__data.__total_seq;
+ cond->__data.__futex = (unsigned int) cond->__data.__total_seq * 2;
+ int futex_val = cond->__data.__futex;
+ /* Signal that a broadcast happened. */
+ ++cond->__data.__broadcast_seq;
+
+ /* We are done. */
+ lll_unlock (cond->__data.__lock, pshared);
+
+ /* Do not use requeue for pshared condvars. */
+ if (cond->__data.__mutex == (void *) ~0l)
+ goto wake_all;
+
+ /* Wake everybody. */
+ pthread_mutex_t *mut = (pthread_mutex_t *) cond->__data.__mutex;
+
+ /* XXX: Kernel so far doesn't support requeue to PI futex. */
+ /* XXX: Kernel so far can only requeue to the same type of futex,
+ in this case private (we don't requeue for pshared condvars). */
+ if (__builtin_expect (mut->__data.__kind
+ & (PTHREAD_MUTEX_PRIO_INHERIT_NP
+ | PTHREAD_MUTEX_PSHARED_BIT), 0))
+ goto wake_all;
+
+ /* lll_futex_requeue returns 0 for success and non-zero
+ for errors. */
+ if (__builtin_expect (lll_futex_requeue (&cond->__data.__futex, 1,
+ INT_MAX, &mut->__data.__lock,
+ futex_val, LLL_PRIVATE), 0))
+ {
+ /* The requeue functionality is not available. */
+ wake_all:
+ lll_futex_wake (&cond->__data.__futex, INT_MAX, pshared);
+ }
+
+ /* That's all. */
+ return 0;
+ }
+
+ /* We are done. */
+ lll_unlock (cond->__data.__lock, pshared);
+
+ return 0;
+}
+
+weak_alias(__pthread_cond_broadcast, pthread_cond_broadcast)