1 /* Copyright (C) 2005-2017 Free Software Foundation, Inc.
2 Contributed by Richard Henderson <rth@redhat.com>.
4 This file is part of the GNU Offloading and Multi Processing Library
7 Libgomp is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
12 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14 FOR A PARTICULAR PURPOSE. See the GNU General Public License for
17 Under Section 7 of GPL version 3, you are granted additional
18 permissions described in the GCC Runtime Library Exception, version
19 3.1, as published by the Free Software Foundation.
21 You should have received a copy of the GNU General Public License and
22 a copy of the GCC Runtime Library Exception along with this program;
23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 <http://www.gnu.org/licenses/>. */
26 /* This is the default implementation of a barrier synchronization mechanism
27 for libgomp. This type is private to the library. Note that we rely on
28 being able to adjust the barrier count while threads are blocked, so the
29 POSIX pthread_barrier_t won't work. */
31 #ifndef GOMP_BARRIER_H
32 #define GOMP_BARRIER_H 1
39 #ifndef HAVE_SYNC_BUILTINS
50 typedef unsigned int gomp_barrier_state_t
;
52 /* The generation field contains a counter in the high bits, with a few
53 low bits dedicated to flags. Note that TASK_PENDING and WAS_LAST can
54 share space because WAS_LAST is never stored back to generation. */
55 #define BAR_TASK_PENDING 1
56 #define BAR_WAS_LAST 1
57 #define BAR_WAITING_FOR_TASK 2
58 #define BAR_CANCELLED 4
61 extern void gomp_barrier_init (gomp_barrier_t
*, unsigned);
62 extern void gomp_barrier_reinit (gomp_barrier_t
*, unsigned);
63 extern void gomp_barrier_destroy (gomp_barrier_t
*);
65 extern void gomp_barrier_wait (gomp_barrier_t
*);
66 extern void gomp_barrier_wait_end (gomp_barrier_t
*, gomp_barrier_state_t
);
67 extern void gomp_team_barrier_wait (gomp_barrier_t
*);
68 extern void gomp_team_barrier_wait_end (gomp_barrier_t
*,
69 gomp_barrier_state_t
);
70 extern bool gomp_team_barrier_wait_cancel (gomp_barrier_t
*);
71 extern bool gomp_team_barrier_wait_cancel_end (gomp_barrier_t
*,
72 gomp_barrier_state_t
);
73 extern void gomp_team_barrier_wake (gomp_barrier_t
*, int);
75 extern void gomp_team_barrier_cancel (struct gomp_team
*);
77 static inline gomp_barrier_state_t
78 gomp_barrier_wait_start (gomp_barrier_t
*bar
)
81 gomp_mutex_lock (&bar
->mutex1
);
82 ret
= bar
->generation
& (-BAR_INCR
| BAR_CANCELLED
);
83 if (++bar
->arrived
== bar
->total
)
88 static inline gomp_barrier_state_t
89 gomp_barrier_wait_cancel_start (gomp_barrier_t
*bar
)
92 gomp_mutex_lock (&bar
->mutex1
);
93 ret
= bar
->generation
& (-BAR_INCR
| BAR_CANCELLED
);
94 if (ret
& BAR_CANCELLED
)
96 if (++bar
->arrived
== bar
->total
)
102 gomp_team_barrier_wait_final (gomp_barrier_t
*bar
)
104 gomp_team_barrier_wait (bar
);
108 gomp_barrier_last_thread (gomp_barrier_state_t state
)
110 return state
& BAR_WAS_LAST
;
114 gomp_barrier_wait_last (gomp_barrier_t
*bar
)
116 gomp_barrier_wait (bar
);
119 /* All the inlines below must be called with team->task_lock
123 gomp_team_barrier_set_task_pending (gomp_barrier_t
*bar
)
125 bar
->generation
|= BAR_TASK_PENDING
;
129 gomp_team_barrier_clear_task_pending (gomp_barrier_t
*bar
)
131 bar
->generation
&= ~BAR_TASK_PENDING
;
135 gomp_team_barrier_set_waiting_for_tasks (gomp_barrier_t
*bar
)
137 bar
->generation
|= BAR_WAITING_FOR_TASK
;
141 gomp_team_barrier_waiting_for_tasks (gomp_barrier_t
*bar
)
143 return (bar
->generation
& BAR_WAITING_FOR_TASK
) != 0;
147 gomp_team_barrier_cancelled (gomp_barrier_t
*bar
)
149 return __builtin_expect ((bar
->generation
& BAR_CANCELLED
) != 0, 0);
153 gomp_team_barrier_done (gomp_barrier_t
*bar
, gomp_barrier_state_t state
)
155 bar
->generation
= (state
& -BAR_INCR
) + BAR_INCR
;
158 #endif /* GOMP_BARRIER_H */