818ab71a41
From-SVN: r232055
300 lines
7.1 KiB
C
300 lines
7.1 KiB
C
/* Copyright (C) 2005-2016 Free Software Foundation, Inc.
|
|
Contributed by Richard Henderson <rth@redhat.com>.
|
|
|
|
This file is part of the GNU Offloading and Multi Processing Library
|
|
(libgomp).
|
|
|
|
Libgomp is free software; you can redistribute it and/or modify it
|
|
under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3, or (at your option)
|
|
any later version.
|
|
|
|
Libgomp 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 General Public License for
|
|
more details.
|
|
|
|
Under Section 7 of GPL version 3, you are granted additional
|
|
permissions described in the GCC Runtime Library Exception, version
|
|
3.1, as published by the Free Software Foundation.
|
|
|
|
You should have received a copy of the GNU General Public License and
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* This is the default implementation of a barrier synchronization mechanism
|
|
for libgomp. This type is private to the library. Note that we rely on
|
|
being able to adjust the barrier count while threads are blocked, so the
|
|
POSIX pthread_barrier_t won't work. */
|
|
|
|
#include "libgomp.h"
|
|
|
|
|
|
void
|
|
gomp_barrier_init (gomp_barrier_t *bar, unsigned count)
|
|
{
|
|
gomp_mutex_init (&bar->mutex1);
|
|
#ifndef HAVE_SYNC_BUILTINS
|
|
gomp_mutex_init (&bar->mutex2);
|
|
#endif
|
|
gomp_sem_init (&bar->sem1, 0);
|
|
gomp_sem_init (&bar->sem2, 0);
|
|
bar->total = count;
|
|
bar->arrived = 0;
|
|
bar->generation = 0;
|
|
bar->cancellable = false;
|
|
}
|
|
|
|
void
|
|
gomp_barrier_destroy (gomp_barrier_t *bar)
|
|
{
|
|
/* Before destroying, make sure all threads have left the barrier. */
|
|
gomp_mutex_lock (&bar->mutex1);
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
|
|
gomp_mutex_destroy (&bar->mutex1);
|
|
#ifndef HAVE_SYNC_BUILTINS
|
|
gomp_mutex_destroy (&bar->mutex2);
|
|
#endif
|
|
gomp_sem_destroy (&bar->sem1);
|
|
gomp_sem_destroy (&bar->sem2);
|
|
}
|
|
|
|
void
|
|
gomp_barrier_reinit (gomp_barrier_t *bar, unsigned count)
|
|
{
|
|
gomp_mutex_lock (&bar->mutex1);
|
|
bar->total = count;
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
}
|
|
|
|
void
|
|
gomp_barrier_wait_end (gomp_barrier_t *bar, gomp_barrier_state_t state)
|
|
{
|
|
unsigned int n;
|
|
|
|
if (state & BAR_WAS_LAST)
|
|
{
|
|
n = --bar->arrived;
|
|
if (n > 0)
|
|
{
|
|
do
|
|
gomp_sem_post (&bar->sem1);
|
|
while (--n != 0);
|
|
gomp_sem_wait (&bar->sem2);
|
|
}
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
}
|
|
else
|
|
{
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
gomp_sem_wait (&bar->sem1);
|
|
|
|
#ifdef HAVE_SYNC_BUILTINS
|
|
n = __sync_add_and_fetch (&bar->arrived, -1);
|
|
#else
|
|
gomp_mutex_lock (&bar->mutex2);
|
|
n = --bar->arrived;
|
|
gomp_mutex_unlock (&bar->mutex2);
|
|
#endif
|
|
|
|
if (n == 0)
|
|
gomp_sem_post (&bar->sem2);
|
|
}
|
|
}
|
|
|
|
void
|
|
gomp_barrier_wait (gomp_barrier_t *barrier)
|
|
{
|
|
gomp_barrier_wait_end (barrier, gomp_barrier_wait_start (barrier));
|
|
}
|
|
|
|
void
|
|
gomp_team_barrier_wait_end (gomp_barrier_t *bar, gomp_barrier_state_t state)
|
|
{
|
|
unsigned int n;
|
|
|
|
state &= ~BAR_CANCELLED;
|
|
if (state & BAR_WAS_LAST)
|
|
{
|
|
n = --bar->arrived;
|
|
struct gomp_thread *thr = gomp_thread ();
|
|
struct gomp_team *team = thr->ts.team;
|
|
|
|
team->work_share_cancelled = 0;
|
|
if (team->task_count)
|
|
{
|
|
gomp_barrier_handle_tasks (state);
|
|
if (n > 0)
|
|
gomp_sem_wait (&bar->sem2);
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
return;
|
|
}
|
|
|
|
bar->generation = state + BAR_INCR - BAR_WAS_LAST;
|
|
if (n > 0)
|
|
{
|
|
do
|
|
gomp_sem_post (&bar->sem1);
|
|
while (--n != 0);
|
|
gomp_sem_wait (&bar->sem2);
|
|
}
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
}
|
|
else
|
|
{
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
int gen;
|
|
do
|
|
{
|
|
gomp_sem_wait (&bar->sem1);
|
|
gen = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
if (gen & BAR_TASK_PENDING)
|
|
{
|
|
gomp_barrier_handle_tasks (state);
|
|
gen = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
}
|
|
}
|
|
while (gen != state + BAR_INCR);
|
|
|
|
#ifdef HAVE_SYNC_BUILTINS
|
|
n = __sync_add_and_fetch (&bar->arrived, -1);
|
|
#else
|
|
gomp_mutex_lock (&bar->mutex2);
|
|
n = --bar->arrived;
|
|
gomp_mutex_unlock (&bar->mutex2);
|
|
#endif
|
|
|
|
if (n == 0)
|
|
gomp_sem_post (&bar->sem2);
|
|
}
|
|
}
|
|
|
|
bool
|
|
gomp_team_barrier_wait_cancel_end (gomp_barrier_t *bar,
|
|
gomp_barrier_state_t state)
|
|
{
|
|
unsigned int n;
|
|
|
|
if (state & BAR_WAS_LAST)
|
|
{
|
|
bar->cancellable = false;
|
|
n = --bar->arrived;
|
|
struct gomp_thread *thr = gomp_thread ();
|
|
struct gomp_team *team = thr->ts.team;
|
|
|
|
team->work_share_cancelled = 0;
|
|
if (team->task_count)
|
|
{
|
|
gomp_barrier_handle_tasks (state);
|
|
if (n > 0)
|
|
gomp_sem_wait (&bar->sem2);
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
return false;
|
|
}
|
|
|
|
bar->generation = state + BAR_INCR - BAR_WAS_LAST;
|
|
if (n > 0)
|
|
{
|
|
do
|
|
gomp_sem_post (&bar->sem1);
|
|
while (--n != 0);
|
|
gomp_sem_wait (&bar->sem2);
|
|
}
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
}
|
|
else
|
|
{
|
|
if (state & BAR_CANCELLED)
|
|
{
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
return true;
|
|
}
|
|
bar->cancellable = true;
|
|
gomp_mutex_unlock (&bar->mutex1);
|
|
int gen;
|
|
do
|
|
{
|
|
gomp_sem_wait (&bar->sem1);
|
|
gen = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
if (gen & BAR_CANCELLED)
|
|
break;
|
|
if (gen & BAR_TASK_PENDING)
|
|
{
|
|
gomp_barrier_handle_tasks (state);
|
|
gen = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
if (gen & BAR_CANCELLED)
|
|
break;
|
|
}
|
|
}
|
|
while (gen != state + BAR_INCR);
|
|
|
|
#ifdef HAVE_SYNC_BUILTINS
|
|
n = __sync_add_and_fetch (&bar->arrived, -1);
|
|
#else
|
|
gomp_mutex_lock (&bar->mutex2);
|
|
n = --bar->arrived;
|
|
gomp_mutex_unlock (&bar->mutex2);
|
|
#endif
|
|
|
|
if (n == 0)
|
|
gomp_sem_post (&bar->sem2);
|
|
if (gen & BAR_CANCELLED)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void
|
|
gomp_team_barrier_wait (gomp_barrier_t *barrier)
|
|
{
|
|
gomp_team_barrier_wait_end (barrier, gomp_barrier_wait_start (barrier));
|
|
}
|
|
|
|
void
|
|
gomp_team_barrier_wake (gomp_barrier_t *bar, int count)
|
|
{
|
|
if (count == 0)
|
|
count = bar->total - 1;
|
|
while (count-- > 0)
|
|
gomp_sem_post (&bar->sem1);
|
|
}
|
|
|
|
bool
|
|
gomp_team_barrier_wait_cancel (gomp_barrier_t *bar)
|
|
{
|
|
gomp_barrier_state_t state = gomp_barrier_wait_cancel_start (bar);
|
|
return gomp_team_barrier_wait_cancel_end (bar, state);
|
|
}
|
|
|
|
void
|
|
gomp_team_barrier_cancel (struct gomp_team *team)
|
|
{
|
|
if (team->barrier.generation & BAR_CANCELLED)
|
|
return;
|
|
gomp_mutex_lock (&team->barrier.mutex1);
|
|
gomp_mutex_lock (&team->task_lock);
|
|
if (team->barrier.generation & BAR_CANCELLED)
|
|
{
|
|
gomp_mutex_unlock (&team->task_lock);
|
|
gomp_mutex_unlock (&team->barrier.mutex1);
|
|
return;
|
|
}
|
|
team->barrier.generation |= BAR_CANCELLED;
|
|
gomp_mutex_unlock (&team->task_lock);
|
|
if (team->barrier.cancellable)
|
|
{
|
|
int n = team->barrier.arrived;
|
|
if (n > 0)
|
|
{
|
|
do
|
|
gomp_sem_post (&team->barrier.sem1);
|
|
while (--n != 0);
|
|
gomp_sem_wait (&team->barrier.sem2);
|
|
}
|
|
team->barrier.cancellable = false;
|
|
}
|
|
gomp_mutex_unlock (&team->barrier.mutex1);
|
|
}
|