diff options
Diffstat (limited to 'pthreads/pthread_barrier_wait.c')
-rw-r--r-- | pthreads/pthread_barrier_wait.c | 208 |
1 files changed, 104 insertions, 104 deletions
diff --git a/pthreads/pthread_barrier_wait.c b/pthreads/pthread_barrier_wait.c index a19582583..e0e97e6c7 100644 --- a/pthreads/pthread_barrier_wait.c +++ b/pthreads/pthread_barrier_wait.c @@ -1,104 +1,104 @@ -/*
- * pthread_barrier_wait.c
- *
- * Description:
- * This translation unit implements barrier primitives.
- *
- * --------------------------------------------------------------------------
- *
- * Pthreads-win32 - POSIX Threads Library for Win32
- * Copyright(C) 1998 John E. Bossom
- * Copyright(C) 1999,2005 Pthreads-win32 contributors
- *
- * Contact Email: rpj@callisto.canberra.edu.au
- *
- * The current list of contributors is contained
- * in the file CONTRIBUTORS included with the source
- * code distribution. The list can also be seen at the
- * following World Wide Web location:
- * http://sources.redhat.com/pthreads-win32/contributors.html
- *
- * This 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 of the License, or (at your option) any later version.
- *
- * This 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 this library in 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 "implement.h"
-
-
-int
-pthread_barrier_wait (pthread_barrier_t * barrier)
-{
- int result;
- pthread_barrier_t b;
-
- ptw32_mcs_local_node_t node;
-
- if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID)
- {
- return EINVAL;
- }
-
- ptw32_mcs_lock_acquire((ptw32_mcs_lock_t *)&(*barrier)->lock, &node);
-
- b = *barrier;
- if (--b->nCurrentBarrierHeight == 0)
- {
- /*
- * We are the last thread to arrive at the barrier before it releases us.
- * Move our MCS local node to the global scope barrier handle so that the
- * last thread out (not necessarily us) can release the lock.
- */
- ptw32_mcs_node_substitute(&b->proxynode, &node);
-
- /*
- * Any threads that have not quite entered sem_wait below when the
- * multiple_post has completed will nevertheless continue through
- * the semaphore (barrier).
- */
- result = (b->nInitialBarrierHeight > 1
- ? sem_post_multiple (&(b->semBarrierBreeched),
- b->nInitialBarrierHeight - 1) : 0);
- }
- else
- {
- ptw32_mcs_lock_release(&node);
- /*
- * Use the non-cancelable version of sem_wait().
- *
- * It is possible that all nInitialBarrierHeight-1 threads are
- * at this point when the last thread enters the barrier, resets
- * nCurrentBarrierHeight = nInitialBarrierHeight and leaves.
- * If pthread_barrier_destroy is called at that moment then the
- * barrier will be destroyed along with the semas.
- */
- result = ptw32_semwait (&(b->semBarrierBreeched));
- }
-
- if ((PTW32_INTERLOCKED_LONG)InterlockedIncrement((LPLONG)&b->nCurrentBarrierHeight)
- == (PTW32_INTERLOCKED_LONG)b->nInitialBarrierHeight)
- {
- /*
- * We are the last thread to cross this barrier
- */
- ptw32_mcs_lock_release(&b->proxynode);
- if (0 == result)
- {
- result = PTHREAD_BARRIER_SERIAL_THREAD;
- }
- }
-
- return (result);
-}
+/* + * pthread_barrier_wait.c + * + * Description: + * This translation unit implements barrier primitives. + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2005 Pthreads-win32 contributors + * + * Contact Email: rpj@callisto.canberra.edu.au + * + * The current list of contributors is contained + * in the file CONTRIBUTORS included with the source + * code distribution. The list can also be seen at the + * following World Wide Web location: + * http://sources.redhat.com/pthreads-win32/contributors.html + * + * This 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 of the License, or (at your option) any later version. + * + * This 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 this library in 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 "implement.h" + + +int +pthread_barrier_wait (pthread_barrier_t * barrier) +{ + int result; + pthread_barrier_t b; + + ptw32_mcs_local_node_t node; + + if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID) + { + return EINVAL; + } + + ptw32_mcs_lock_acquire(&(*barrier)->lock, &node); + + b = *barrier; + if (--b->nCurrentBarrierHeight == 0) + { + /* + * We are the last thread to arrive at the barrier before it releases us. + * Move our MCS local node to the global scope barrier handle so that the + * last thread out (not necessarily us) can release the lock. + */ + ptw32_mcs_node_transfer(&b->proxynode, &node); + + /* + * Any threads that have not quite entered sem_wait below when the + * multiple_post has completed will nevertheless continue through + * the semaphore (barrier). + */ + result = (b->nInitialBarrierHeight > 1 + ? sem_post_multiple (&(b->semBarrierBreeched), + b->nInitialBarrierHeight - 1) : 0); + } + else + { + ptw32_mcs_lock_release(&node); + /* + * Use the non-cancelable version of sem_wait(). + * + * It is possible that all nInitialBarrierHeight-1 threads are + * at this point when the last thread enters the barrier, resets + * nCurrentBarrierHeight = nInitialBarrierHeight and leaves. + * If pthread_barrier_destroy is called at that moment then the + * barrier will be destroyed along with the semas. + */ + result = ptw32_semwait (&(b->semBarrierBreeched)); + } + + if ((PTW32_INTERLOCKED_LONG)PTW32_INTERLOCKED_INCREMENT_LONG((PTW32_INTERLOCKED_LONGPTR)&b->nCurrentBarrierHeight) + == (PTW32_INTERLOCKED_LONG)b->nInitialBarrierHeight) + { + /* + * We are the last thread to cross this barrier + */ + ptw32_mcs_lock_release(&b->proxynode); + if (0 == result) + { + result = PTHREAD_BARRIER_SERIAL_THREAD; + } + } + + return (result); +} |