13c41b2e3e
libgomp/ChangeLog * config/rtems/bar.c: New. * config/rtems/bar.h: Likewise. * config/rtems/mutex.c: Likewise. * config/rtems/mutex.h: Likewise. * config/rtems/sem.c: Likewise. * config/rtems/sem.h: Likewise. * configure.ac (*-*-rtems*): Check that Newlib provides a proper <sys/lock.h> header file. * configure.tgt (*-*-rtems*): Enable RTEMS configuration if supported by Newlib. * configure: Regenerate. From-SVN: r227440
171 lines
5.5 KiB
C
171 lines
5.5 KiB
C
/* Copyright (C) 2005-2015 Free Software Foundation, Inc.
|
|
Contributed by Sebastian Huber <sebastian.huber@embedded-brains.de>.
|
|
|
|
This file is part of the GNU OpenMP 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 RTEMS implementation of a barrier synchronization
|
|
mechanism for libgomp. It is identical to the Linux implementation, except
|
|
that the futex API is slightly different. This type is private to the
|
|
library. */
|
|
|
|
#ifndef GOMP_BARRIER_H
|
|
#define GOMP_BARRIER_H 1
|
|
|
|
#include <sys/lock.h>
|
|
|
|
typedef struct
|
|
{
|
|
/* Make sure total/generation is in a mostly read cacheline, while
|
|
awaited in a separate cacheline. */
|
|
unsigned total __attribute__((aligned (64)));
|
|
unsigned generation;
|
|
struct _Futex_Control futex;
|
|
unsigned awaited __attribute__((aligned (64)));
|
|
unsigned awaited_final;
|
|
} gomp_barrier_t;
|
|
|
|
typedef unsigned int gomp_barrier_state_t;
|
|
|
|
/* The generation field contains a counter in the high bits, with a few
|
|
low bits dedicated to flags. Note that TASK_PENDING and WAS_LAST can
|
|
share space because WAS_LAST is never stored back to generation. */
|
|
#define BAR_TASK_PENDING 1
|
|
#define BAR_WAS_LAST 1
|
|
#define BAR_WAITING_FOR_TASK 2
|
|
#define BAR_CANCELLED 4
|
|
#define BAR_INCR 8
|
|
|
|
static inline void gomp_barrier_init (gomp_barrier_t *bar, unsigned count)
|
|
{
|
|
bar->total = count;
|
|
bar->awaited = count;
|
|
bar->awaited_final = count;
|
|
bar->generation = 0;
|
|
_Futex_Initialize (&bar->futex);
|
|
}
|
|
|
|
static inline void gomp_barrier_reinit (gomp_barrier_t *bar, unsigned count)
|
|
{
|
|
__atomic_add_fetch (&bar->awaited, count - bar->total, MEMMODEL_ACQ_REL);
|
|
bar->total = count;
|
|
}
|
|
|
|
static inline void gomp_barrier_destroy (gomp_barrier_t *bar)
|
|
{
|
|
}
|
|
|
|
extern void gomp_barrier_wait (gomp_barrier_t *);
|
|
extern void gomp_barrier_wait_last (gomp_barrier_t *);
|
|
extern void gomp_barrier_wait_end (gomp_barrier_t *, gomp_barrier_state_t);
|
|
extern void gomp_team_barrier_wait (gomp_barrier_t *);
|
|
extern void gomp_team_barrier_wait_final (gomp_barrier_t *);
|
|
extern void gomp_team_barrier_wait_end (gomp_barrier_t *,
|
|
gomp_barrier_state_t);
|
|
extern bool gomp_team_barrier_wait_cancel (gomp_barrier_t *);
|
|
extern bool gomp_team_barrier_wait_cancel_end (gomp_barrier_t *,
|
|
gomp_barrier_state_t);
|
|
extern void gomp_team_barrier_wake (gomp_barrier_t *, int);
|
|
struct gomp_team;
|
|
extern void gomp_team_barrier_cancel (struct gomp_team *);
|
|
|
|
static inline gomp_barrier_state_t
|
|
gomp_barrier_wait_start (gomp_barrier_t *bar)
|
|
{
|
|
unsigned int ret = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
ret &= -BAR_INCR | BAR_CANCELLED;
|
|
/* A memory barrier is needed before exiting from the various forms
|
|
of gomp_barrier_wait, to satisfy OpenMP API version 3.1 section
|
|
2.8.6 flush Construct, which says there is an implicit flush during
|
|
a barrier region. This is a convenient place to add the barrier,
|
|
so we use MEMMODEL_ACQ_REL here rather than MEMMODEL_ACQUIRE. */
|
|
if (__atomic_add_fetch (&bar->awaited, -1, MEMMODEL_ACQ_REL) == 0)
|
|
ret |= BAR_WAS_LAST;
|
|
return ret;
|
|
}
|
|
|
|
static inline gomp_barrier_state_t
|
|
gomp_barrier_wait_cancel_start (gomp_barrier_t *bar)
|
|
{
|
|
return gomp_barrier_wait_start (bar);
|
|
}
|
|
|
|
/* This is like gomp_barrier_wait_start, except it decrements
|
|
bar->awaited_final rather than bar->awaited and should be used
|
|
for the gomp_team_end barrier only. */
|
|
static inline gomp_barrier_state_t
|
|
gomp_barrier_wait_final_start (gomp_barrier_t *bar)
|
|
{
|
|
unsigned int ret = __atomic_load_n (&bar->generation, MEMMODEL_ACQUIRE);
|
|
ret &= -BAR_INCR | BAR_CANCELLED;
|
|
/* See above gomp_barrier_wait_start comment. */
|
|
if (__atomic_add_fetch (&bar->awaited_final, -1, MEMMODEL_ACQ_REL) == 0)
|
|
ret |= BAR_WAS_LAST;
|
|
return ret;
|
|
}
|
|
|
|
static inline bool
|
|
gomp_barrier_last_thread (gomp_barrier_state_t state)
|
|
{
|
|
return state & BAR_WAS_LAST;
|
|
}
|
|
|
|
/* All the inlines below must be called with team->task_lock
|
|
held. */
|
|
|
|
static inline void
|
|
gomp_team_barrier_set_task_pending (gomp_barrier_t *bar)
|
|
{
|
|
bar->generation |= BAR_TASK_PENDING;
|
|
}
|
|
|
|
static inline void
|
|
gomp_team_barrier_clear_task_pending (gomp_barrier_t *bar)
|
|
{
|
|
bar->generation &= ~BAR_TASK_PENDING;
|
|
}
|
|
|
|
static inline void
|
|
gomp_team_barrier_set_waiting_for_tasks (gomp_barrier_t *bar)
|
|
{
|
|
bar->generation |= BAR_WAITING_FOR_TASK;
|
|
}
|
|
|
|
static inline bool
|
|
gomp_team_barrier_waiting_for_tasks (gomp_barrier_t *bar)
|
|
{
|
|
return (bar->generation & BAR_WAITING_FOR_TASK) != 0;
|
|
}
|
|
|
|
static inline bool
|
|
gomp_team_barrier_cancelled (gomp_barrier_t *bar)
|
|
{
|
|
return __builtin_expect ((bar->generation & BAR_CANCELLED) != 0, 0);
|
|
}
|
|
|
|
static inline void
|
|
gomp_team_barrier_done (gomp_barrier_t *bar, gomp_barrier_state_t state)
|
|
{
|
|
bar->generation = (state & -BAR_INCR) + BAR_INCR;
|
|
}
|
|
|
|
#endif /* GOMP_BARRIER_H */
|