diff options
Diffstat (limited to 'nptl/pthread_cond_broadcast.c')
-rw-r--r-- | nptl/pthread_cond_broadcast.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/nptl/pthread_cond_broadcast.c b/nptl/pthread_cond_broadcast.c new file mode 100644 index 0000000000..2b8b5460f4 --- /dev/null +++ b/nptl/pthread_cond_broadcast.c @@ -0,0 +1,86 @@ +/* Copyright (C) 2003, 2004, 2006 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 <shlib-compat.h> +#include <kernel-features.h> + + +int +__pthread_cond_broadcast (cond) + pthread_cond_t *cond; +{ + /* Make sure we are alone. */ + lll_mutex_lock (cond->__data.__lock); + + /* 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_mutex_unlock (cond->__data.__lock); + + /* 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. */ + if (__builtin_expect (mut->__data.__kind & PTHREAD_MUTEX_PRIO_INHERIT_NP, + 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), 0)) + { + /* The requeue functionality is not available. */ + wake_all: + lll_futex_wake (&cond->__data.__futex, INT_MAX); + } + + /* That's all. */ + return 0; + } + + /* We are done. */ + lll_mutex_unlock (cond->__data.__lock); + + return 0; +} + +versioned_symbol (libpthread, __pthread_cond_broadcast, pthread_cond_broadcast, + GLIBC_2_3_2); |