Mercurial > hg > CbC > CbC_gcc
annotate libgomp/config/linux/mutex.h @ 55:77e2b8dfacca gcc-4.4.5
update it from 4.4.3 to 4.5.0
| author | ryoma <e075725@ie.u-ryukyu.ac.jp> |
|---|---|
| date | Fri, 12 Feb 2010 23:39:51 +0900 |
| parents | a06113de4d67 |
| children | 04ced10e8804 |
| rev | line source |
|---|---|
| 0 | 1 /* Copyright (C) 2005, 2009 Free Software Foundation, Inc. |
| 2 Contributed by Richard Henderson <rth@redhat.com>. | |
| 3 | |
| 4 This file is part of the GNU OpenMP Library (libgomp). | |
| 5 | |
| 6 Libgomp is free software; you can redistribute it and/or modify it | |
| 7 under the terms of the GNU General Public License as published by | |
| 8 the Free Software Foundation; either version 3, or (at your option) | |
| 9 any later version. | |
| 10 | |
| 11 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY | |
| 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS | |
| 13 FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
| 14 more details. | |
| 15 | |
| 16 Under Section 7 of GPL version 3, you are granted additional | |
| 17 permissions described in the GCC Runtime Library Exception, version | |
| 18 3.1, as published by the Free Software Foundation. | |
| 19 | |
| 20 You should have received a copy of the GNU General Public License and | |
| 21 a copy of the GCC Runtime Library Exception along with this program; | |
| 22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | |
| 23 <http://www.gnu.org/licenses/>. */ | |
| 24 | |
| 25 /* This is a Linux specific implementation of a mutex synchronization | |
| 26 mechanism for libgomp. This type is private to the library. This | |
| 27 implementation uses atomic instructions and the futex syscall. */ | |
| 28 | |
| 29 #ifndef GOMP_MUTEX_H | |
| 30 #define GOMP_MUTEX_H 1 | |
| 31 | |
| 32 typedef int gomp_mutex_t; | |
| 33 | |
| 34 #define GOMP_MUTEX_INIT_0 1 | |
| 35 | |
| 36 static inline void gomp_mutex_init (gomp_mutex_t *mutex) | |
| 37 { | |
| 38 *mutex = 0; | |
| 39 } | |
| 40 | |
| 41 extern void gomp_mutex_lock_slow (gomp_mutex_t *mutex); | |
| 42 static inline void gomp_mutex_lock (gomp_mutex_t *mutex) | |
| 43 { | |
| 44 if (!__sync_bool_compare_and_swap (mutex, 0, 1)) | |
| 45 gomp_mutex_lock_slow (mutex); | |
| 46 } | |
| 47 | |
| 48 extern void gomp_mutex_unlock_slow (gomp_mutex_t *mutex); | |
| 49 static inline void gomp_mutex_unlock (gomp_mutex_t *mutex) | |
| 50 { | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
changeset
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51 /* Warning: By definition __sync_lock_test_and_set() does not have |
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77e2b8dfacca
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ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
changeset
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52 proper memory barrier semantics for a mutex unlock operation. |
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77e2b8dfacca
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ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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53 However, this default implementation is written assuming that it |
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77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
changeset
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54 does, which is true for some targets. |
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77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
changeset
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55 |
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77e2b8dfacca
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ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
changeset
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56 Targets that require additional memory barriers before |
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77e2b8dfacca
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ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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diff
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57 __sync_lock_test_and_set to achieve the release semantics of |
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77e2b8dfacca
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ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
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58 mutex unlock, are encouraged to include |
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77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
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59 "config/linux/ia64/mutex.h" in a target specific mutex.h instead |
|
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
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60 of using this file. */ |
| 0 | 61 int val = __sync_lock_test_and_set (mutex, 0); |
| 62 if (__builtin_expect (val > 1, 0)) | |
| 63 gomp_mutex_unlock_slow (mutex); | |
| 64 } | |
| 65 | |
| 66 static inline void gomp_mutex_destroy (gomp_mutex_t *mutex) | |
| 67 { | |
| 68 } | |
| 69 | |
| 70 #endif /* GOMP_MUTEX_H */ |