1 /* 2 Copyright (c) 2003-2014 Erwin Coumans http://bullet.googlecode.com 3 4 This software is provided 'as-is', without any express or implied warranty. 5 In no event will the authors be held liable for any damages arising from the use of this software. 6 Permission is granted to anyone to use this software for any purpose, 7 including commercial applications, and to alter it and redistribute it freely, 8 subject to the following restrictions: 9 10 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 11 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 12 3. This notice may not be removed or altered from any source distribution. 13 */ 14 15 16 17 #ifndef BT_THREADS_H 18 #define BT_THREADS_H 19 20 #include "btScalar.h" // has definitions like SIMD_FORCE_INLINE 21 22 /// 23 /// btSpinMutex -- lightweight spin-mutex implemented with atomic ops, never puts 24 /// a thread to sleep because it is designed to be used with a task scheduler 25 /// which has one thread per core and the threads don't sleep until they 26 /// run out of tasks. Not good for general purpose use. 27 /// 28 class btSpinMutex 29 { 30 int mLock; 31 32 public: btSpinMutex()33 btSpinMutex() 34 { 35 mLock = 0; 36 } 37 void lock(); 38 void unlock(); 39 bool tryLock(); 40 }; 41 42 #if BT_THREADSAFE 43 44 // for internal Bullet use only btMutexLock(btSpinMutex * mutex)45SIMD_FORCE_INLINE void btMutexLock( btSpinMutex* mutex ) 46 { 47 mutex->lock(); 48 } 49 btMutexUnlock(btSpinMutex * mutex)50SIMD_FORCE_INLINE void btMutexUnlock( btSpinMutex* mutex ) 51 { 52 mutex->unlock(); 53 } 54 btMutexTryLock(btSpinMutex * mutex)55SIMD_FORCE_INLINE bool btMutexTryLock( btSpinMutex* mutex ) 56 { 57 return mutex->tryLock(); 58 } 59 60 // for internal use only 61 bool btIsMainThread(); 62 unsigned int btGetCurrentThreadIndex(); 63 const unsigned int BT_MAX_THREAD_COUNT = 64; 64 65 #else 66 67 // for internal Bullet use only 68 // if BT_THREADSAFE is undefined or 0, should optimize away to nothing btMutexLock(btSpinMutex *)69SIMD_FORCE_INLINE void btMutexLock( btSpinMutex* ) {} btMutexUnlock(btSpinMutex *)70SIMD_FORCE_INLINE void btMutexUnlock( btSpinMutex* ) {} btMutexTryLock(btSpinMutex *)71SIMD_FORCE_INLINE bool btMutexTryLock( btSpinMutex* ) {return true;} 72 #endif 73 74 75 #endif //BT_THREADS_H 76