OpenMPI  0.1.1
malloc-machine.h
1 /* Basic platform-independent macro definitions for mutexes,
2  thread-specific data and parameters for malloc.
3  Copyright (C) 2003 Free Software Foundation, Inc.
4  This file is part of the GNU C Library.
5 
6  The GNU C Library is free software; you can redistribute it and/or
7  modify it under the terms of the GNU Lesser General Public
8  License as published by the Free Software Foundation; either
9  version 2.1 of the License, or (at your option) any later version.
10 
11  The GNU C Library is distributed in the hope that it will be useful,
12  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  Lesser General Public License for more details.
15 
16  You should have received a copy of the GNU Lesser General Public
17  License along with the GNU C Library; if not, write to the Free
18  Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19  02111-1307 USA. */
20 
21 #ifndef _GENERIC_MALLOC_MACHINE_H
22 #define _GENERIC_MALLOC_MACHINE_H
23 
24 #include <atomic.h>
25 
26 #ifndef mutex_init /* No threads, provide dummy macros */
27 
28 # define NO_THREADS
29 
30 /* The mutex functions used to do absolutely nothing, i.e. lock,
31  trylock and unlock would always just return 0. However, even
32  without any concurrently active threads, a mutex can be used
33  legitimately as an `in use' flag. To make the code that is
34  protected by a mutex async-signal safe, these macros would have to
35  be based on atomic test-and-set operations, for example. */
36 typedef int mutex_t;
37 
38 # define mutex_init(m) (*(m) = 0)
39 # define mutex_lock(m) ((*(m) = 1), 0)
40 # define mutex_trylock(m) (*(m) ? 1 : ((*(m) = 1), 0))
41 # define mutex_unlock(m) (*(m) = 0)
42 
43 typedef void *tsd_key_t;
44 # define tsd_key_create(key, destr) do {} while(0)
45 # define tsd_setspecific(key, data) ((key) = (data))
46 # define tsd_getspecific(key, vptr) (vptr = (key))
47 
48 # define thread_atfork(prepare, parent, child) do {} while(0)
49 
50 #endif /* !defined mutex_init */
51 
52 #ifndef atomic_full_barrier
53 # define atomic_full_barrier() __asm ("" ::: "memory")
54 #endif
55 
56 #ifndef atomic_read_barrier
57 # define atomic_read_barrier() atomic_full_barrier ()
58 #endif
59 
60 #ifndef atomic_write_barrier
61 # define atomic_write_barrier() atomic_full_barrier ()
62 #endif
63 
64 #ifndef DEFAULT_TOP_PAD
65 # define DEFAULT_TOP_PAD 131072
66 #endif
67 
68 #endif /* !defined(_GENERIC_MALLOC_MACHINE_H) */