Mercurial > sdl-ios-xcode

annotate src/atomic/SDL_spinlock.c @ 5048:187d7d446306

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
PS3 Linux is no more...
author Sam Lantinga <slouken@libsdl.org>
date Wed, 19 Jan 2011 22:25:40 -0800
parents fffb33ae85e8
children fd125217f00c
rev   line source
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
1 /*
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
3 Copyright (C) 1997-2010 Sam Lantinga
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
4
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
6 modify it under the terms of the GNU Lesser General Public
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
8 version 2.1 of the License, or (at your option) any later version.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
9
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
13 Lesser General Public License for more details.
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
14
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
15 You should have received a copy of the GNU Lesser General Public
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
16 License along with this library; if not, write to the Free Software
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
18
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
19 Sam Lantinga
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
20 slouken@libsdl.org
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
21 */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
22 #include "SDL_stdinc.h"
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
23
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
24 #include "SDL_atomic.h"
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
25 #include "SDL_timer.h"
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
26
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
27
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
28 /* This function is where all the magic happens... */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
29 SDL_bool
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
30 SDL_AtomicTryLock(SDL_SpinLock *lock)
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
31 {
5028
fffb33ae85e8 Whoops, good catch from Greg Jandl
Sam Lantinga <slouken@libsdl.org>
parents: 5015
diff changeset
32 #if defined(_MSC_VER)
5015
1bf9e38431ec Use compiler intrinsics on Windows
Sam Lantinga <slouken@libsdl.org>
parents: 5004
diff changeset
33 SDL_COMPILE_TIME_ASSERT(locksize, sizeof(*lock) == sizeof(long));
1bf9e38431ec Use compiler intrinsics on Windows
Sam Lantinga <slouken@libsdl.org>
parents: 5004
diff changeset
34 return (_InterlockedExchange((long*)lock, 1) == 0);
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
35
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
36 #elif defined(__MACOSX__)
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
37 return OSAtomicCompareAndSwap32Barrier(0, 1, lock);
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
38
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
39 #elif defined(HAVE_GCC_ATOMICS)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
40 return (__sync_lock_test_and_set(lock, 1) == 0);
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
41
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
42 #elif defined(__GNUC__) && defined(__arm__) && defined(__ARM_ARCH_5__)
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
43 int result;
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
44 __asm__ __volatile__ (
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
45 "swp %0, %1, [%2]\n"
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
46 : "=&r,&r" (result) : "r,0" (1), "r,r" (lock) : "memory");
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
47 return (result == 0);
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
48
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
49 #elif defined(__GNUC__) && defined(__arm__)
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
50 int result;
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
51 __asm__ __volatile__ (
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
52 "ldrex %0, [%2]\nteq %0, #0\nstrexeq %0, %1, [%2]"
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
53 : "=&r" (result) : "r" (1), "r" (lock) : "cc", "memory");
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
54 return (result == 0);
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
55
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
56 #else
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
57 /* Need CPU instructions for spinlock here! */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
58 __need_spinlock_implementation__
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
59 #endif
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
60 }
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
61
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
62 void
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
63 SDL_AtomicLock(SDL_SpinLock *lock)
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
64 {
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
65 /* FIXME: Should we have an eventual timeout? */
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
66 while (!SDL_AtomicTryLock(lock)) {
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
67 SDL_Delay(0);
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
68 }
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
69 }
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
70
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
71 void
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
72 SDL_AtomicUnlock(SDL_SpinLock *lock)
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
73 {
5004
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics.
Sam Lantinga <slouken@libsdl.org>
parents: 5003
diff changeset
74 /* Assuming atomic assignment operation and full memory barrier in lock */
5003
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
75 *lock = 0;
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
76 }
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
77
3a95a2b93eb3 Updated the atomic API for better use cases
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
78 /* vi: set ts=4 sw=4 expandtab: */