From 7b808fcab731759c6880d554f69bc73f7fd5387f Mon Sep 17 00:00:00 2001 From: Bob Pendleton Date: Thu, 17 Sep 2009 20:35:12 +0000 Subject: [PATCH] The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. The linux code appears to be complete and *should* be the base of all Unix and GCC based versions. The macosx and win32 versions are currently just copies of the dummy code. I will begin working on the windows version as soon as this check in is done. I need someone to work on the Mac OS X version. I'm afraid that this check in will break QNX (Sorry!) --- include/SDL_atomic.h | 53 +- src/atomic/dummy/SDL_atomic.c | 821 ++++++------------------------- src/atomic/linux/SDL_atomic.c | 815 +++++++------------------------ src/atomic/macosx/SDL_atomic.c | 821 ++++++------------------------- src/atomic/win32/SDL_atomic.c | 861 +++++++-------------------------- test/testatomic.c | 33 +- 6 files changed, 656 insertions(+), 2748 deletions(-) diff --git a/include/SDL_atomic.h b/include/SDL_atomic.h index ceddf8974..6fa97d499 100644 --- a/include/SDL_atomic.h +++ b/include/SDL_atomic.h @@ -18,6 +18,8 @@ Sam Lantinga slouken@libsdl.org + + Contributed by Bob Pendleton, bob@pendleton.com */ /** @@ -46,48 +48,50 @@ extern "C" { * processor specific atomic operations. When possible they are * implemented as true processor specific atomic operations. When that * is not possible the are implemented using locks that *do* use the - * available atomic operations. In rare cases they may be implemented - * using SDL's mutex fuctions. + * available atomic operations. + * + * At the very minimum spin locks must be implemented. Without spin + * locks it is not possible (AFAICT) to emulate the rest of the atomic + * operations. */ /* Function prototypes */ -/* 32 bit atomic operations */ +/** + * SDL AtomicLock. + * + * The spin lock functions and type are required and can not be + * emulated because they are used in the emulation code. + */ + +typedef volatile Uint32 SDL_SpinLock; /** - * \fn int SDL_AtomicExchange32(volatile Uint32 * ptr, Uint32 value) + * \fn void SDL_AtomicLock(SDL_SpinLock *lock); * - * \brief Atomically exchange two 32 bit values. + * \brief Lock a spin lock by setting it to a none zero value. * - * \return the value point to by ptr. - * - * \param ptr points to the value to be fetched from *ptr. - * \param value is value to be stored at *ptr. - * - * The current value stored at *ptr is returned and it is replaced - * with value. This function can be used to implement SDL_TestThenSet. + * \param lock points to the lock. * */ -extern DECLSPEC Uint32 SDLCALL SDL_AtomicExchange32(volatile Uint32 * ptr, Uint32 value); +extern DECLSPEC void SDLCALL SDL_AtomicLock(SDL_SpinLock *lock); /** - * \fn int SDL_AtomicCompareThenSet32(volatile Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue) - * - * \brief If *ptr == oldvalue then replace the contents of *ptr by new value. + * \fn void SDL_AtomicUnlock(SDL_SpinLock *lock); * - * \return true if the newvalue was stored. + * \brief Unlock a spin lock by setting it to 0. Always returns immediately * - * \param *ptr is the value to be compared and replaced. - * \param oldvalue is value to be compared to *ptr. - * \param newvalue is value to be stored at *ptr. + * \param lock points to the lock. * */ -extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCompareThenSet32(volatile Uint32 * ptr, - Uint32 oldvalue, Uint32 newvalue); +extern DECLSPEC void SDLCALL SDL_AtomicUnlock(SDL_SpinLock *lock); + +/* 32 bit atomic operations */ + /** * \fn SDL_bool SDL_AtomicTestThenSet32(volatile Uint32 * ptr); * - * \brief Check to see if *ptr == 0 and set it to non-zero. + * \brief Check to see if *ptr == 0 and set it to 1. * * \return SDL_True if the value pointed to by ptr was zero and * SDL_False if it was not zero @@ -211,9 +215,6 @@ extern DECLSPEC Uint32 SDLCALL SDL_AtomicSubtractThenFetch32(volatile Uint32 * p /* 64 bit atomic operations */ #ifdef SDL_HAS_64BIT_TYPE -extern DECLSPEC Uint64 SDLCALL SDL_AtomicExchange64(volatile Uint64 * ptr, Uint64 value); -extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCompareThenSet64(volatile Uint64 * ptr, - Uint64 oldvalue, Uint64 newvalue); extern DECLSPEC SDL_bool SDLCALL SDL_AtomicTestThenSet64(volatile Uint64 * ptr); extern DECLSPEC void SDLCALL SDL_AtomicClear64(volatile Uint64 * ptr); extern DECLSPEC Uint64 SDLCALL SDL_AtomicFetchThenIncrement64(volatile Uint64 * ptr); diff --git a/src/atomic/dummy/SDL_atomic.c b/src/atomic/dummy/SDL_atomic.c index de3e52170..b2a7e7a7c 100644 --- a/src/atomic/dummy/SDL_atomic.c +++ b/src/atomic/dummy/SDL_atomic.c @@ -1,639 +1,162 @@ /* - SDL - Simple DirectMedia Layer - Copyright (C) 1997-2009 Sam Lantinga + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2009 Sam Lantinga - This library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - Sam Lantinga - slouken@libsdl.org + Sam Lantinga + slouken@libsdl.org + + Contributed by Bob Pendleton, bob@pendleton.com */ #include "SDL_stdinc.h" #include "SDL_atomic.h" +#include "SDL_error.h" + /* - This file provides 8, 16, 32, and 64 bit atomic operations. If the + This file provides 32, and 64 bit atomic operations. If the operations are provided by the native hardware and operating system they are used. If they are not then the operations are emulated - using the SDL mutex operations. - */ - -/* - First, detect whether the operations are supported and create - #defines that indicate that they do exist. The goal is to have all - the system dependent code in the top part of the file so that the - bottom can be use unchanged across all platforms. - - Second, #define all the operations in each size class that are - supported. Doing this allows supported operations to be used along - side of emulated operations. + using the SDL spin lock operations. If spin lock can not be + implemented then these functions must fail. */ /* - Emmulated version. - - Assume there is no support for atomic operations. All such - operations are implemented using SDL mutex operations. - */ - -#ifdef EMULATED_ATOMIC_OPERATIONS -#undef EMULATED_ATOMIC_OPERATIONS -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_8_BIT_OPS - -#define nativeExchange8(ptr, value) () -#define nativeCompareThenSet8(ptr, oldvalue, newvalue) () -#define nativeTestThenSet8(ptr) () -#define nativeClear8(ptr) () -#define nativeFetchThenIncrement8(ptr) () -#define nativeFetchThenDecrement8(ptr) () -#define nativeFetchThenAdd8(ptr, value) () -#define nativeFetchThenSubtract8(ptr, value) () -#define nativeIncrementThenFetch8(ptr) () -#define nativeDecrementThenFetch8(ptr) () -#define nativeAddThenFetch8(ptr, value) () -#define nativeSubtractThenFetch8(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_16_BIT_OPS - -#define nativeExchange16(ptr, value) () -#define nativeCompareThenSet16(ptr, oldvalue, newvalue) () -#define nativeTestThenSet16(ptr) () -#define nativeClear16(ptr) () -#define nativeFetchThenIncrement16(ptr) () -#define nativeFetchThenDecrement16(ptr) () -#define nativeFetchThenAdd16(ptr, value) () -#define nativeFetchThenSubtract16(ptr, value) () -#define nativeIncrementThenFetch16(ptr) () -#define nativeDecrementThenFetch16(ptr) () -#define nativeAddThenFetch16(ptr, value) () -#define nativeSubtractThenFetch16(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_32_BIT_OPS - -#define nativeExchange32(ptr, value) () -#define nativeCompareThenSet32(ptr, oldvalue, newvalue) () -#define nativeTestThenSet32(ptr) () -#define nativeClear32(ptr) () -#define nativeFetchThenIncrement32(ptr) () -#define nativeFetchThenDecrement32(ptr) () -#define nativeFetchThenAdd32(ptr, value) () -#define nativeFetchThenSubtract32(ptr, value) () -#define nativeIncrementThenFetch32(ptr) () -#define nativeDecrementThenFetch32(ptr) () -#define nativeAddThenFetch32(ptr, value) () -#define nativeSubtractThenFetch32(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_64_BIT_OPS - -#define nativeExchange64(ptr, value) () -#define nativeCompareThenSet64(ptr, oldvalue, newvalue) () -#define nativeTestThenSet64(ptr) () -#define nativeClear64(ptr) () -#define nativeFetchThenIncrement64(ptr) () -#define nativeFetchThenDecrement64(ptr) () -#define nativeFetchThenAdd64(ptr, value) () -#define nativeFetchThenSubtract64(ptr, value) () -#define nativeIncrementThenFetch64(ptr) () -#define nativeDecrementThenFetch64(ptr) () -#define nativeAddThenFetch64(ptr, value) () -#define nativeSubtractThenFetch64(ptr, value) () -#endif - -/* -If any of the operations are not provided then we must emulate some of -them. - */ - -#if !defined(HAVE_ALL_8_BIT_OPS) || !defined(HAVE_ALL_16_BIT_OPS) || !defined(HAVE_ALL_32_BIT_OPS) || !defined(HAVE_ALL_64_BIT_OPS) - -#include "SDL_mutex.h" -#include "SDL_error.h" - -static SDL_mutex * lock = NULL; - -static __inline__ void -privateWaitLock() -{ - if(NULL == lock) - { - lock = SDL_CreateMutex(); - if (NULL == lock) - { - SDL_SetError("SDL_atomic.c: can't create a mutex"); - return; - } - } - - if (-1 == SDL_LockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't lock mutex"); - } -} - -static __inline__ void -privateUnlock() -{ - if (-1 == SDL_UnlockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't unlock mutex"); - } -} - -#endif - -/* 8 bit atomic operations */ - -Uint8 -SDL_AtomicExchange8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeExchange8 - return nativeExchange8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet8(volatile Uint8 * ptr, Uint8 oldvalue, Uint8 newvalue) -{ -#ifdef nativeCompareThenSet8 - return (SDL_bool)nativeCompareThenSet8(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet8(volatile Uint8 * ptr) -{ -#ifdef nativeTestThenSet8 - return (SDL_bool)nativeTestThenSet8(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear8(volatile Uint8 * ptr) -{ -#ifdef nativeClear8 - nativeClear8(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); - - return; -#endif -} - -Uint8 -SDL_AtomicFetchThenIncrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenIncrement8 - return nativeFetchThenIncrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenDecrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenDecrement8 - return nativeFetchThenDecrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenAdd8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenAdd8 - return nativeFetchThenAdd8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenSubtract8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenSubtract8 - return nativeFetchThenSubtract8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicIncrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeIncrementThenFetch8 - return nativeIncrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicDecrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeDecrementThenFetch8 - return nativeDecrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicAddThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeAddThenFetch8 - return nativeAddThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicSubtractThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeSubtractThenFetch8 - return nativeSubtractThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -/* 16 bit atomic operations */ - -Uint16 -SDL_AtomicExchange16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeExchange16 - return nativeExchange16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet16(volatile Uint16 * ptr, Uint16 oldvalue, Uint16 newvalue) -{ -#ifdef nativeCompareThenSet16 - return (SDL_bool)nativeCompareThenSet16(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); + DUMMY VERSION. - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet16(volatile Uint16 * ptr) -{ -#ifdef nativeTestThenSet16 - return (SDL_bool)nativeTestThenSet16(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear16(volatile Uint16 * ptr) -{ -#ifdef nativeClear16 - nativeClear16(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); + This version of the code assumes there is no support for atomic + operations. Therefore, every function sets the SDL error + message. Oddly enough, if you only have one thread then this + version actuallys works. +*/ - return; -#endif -} +/* + Native spinlock routines. Because this is the dummy implementation + these will always call SDL_SetError() and do nothing. +*/ -Uint16 -SDL_AtomicFetchThenIncrement16(volatile Uint16 * ptr) +void +SDL_AtomicLock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenIncrement16 - return nativeFetchThenIncrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenDecrement16(volatile Uint16 * ptr) +void +SDL_AtomicUnlock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenDecrement16 - return nativeFetchThenDecrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenAdd16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenAdd16 - return nativeFetchThenAdd16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} +/* + Note that platform specific versions can be built from this version + by changing the #undefs to #defines and adding platform specific + code. +*/ -Uint16 -SDL_AtomicFetchThenSubtract16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenSubtract16 - return nativeFetchThenSubtract16(ptr, value); -#else - Uint16 tmp = 0; +#undef nativeTestThenSet32 +#undef nativeClear32 +#undef nativeFetchThenIncrement32 +#undef nativeFetchThenDecrement32 +#undef nativeFetchThenAdd32 +#undef nativeFetchThenSubtract32 +#undef nativeIncrementThenFetch32 +#undef nativeDecrementThenFetch32 +#undef nativeAddThenFetch32 +#undef nativeSubtractThenFetch32 + +#undef nativeTestThenSet64 +#undef nativeClear64 +#undef nativeFetchThenIncrement64 +#undef nativeFetchThenDecrement64 +#undef nativeFetchThenAdd64 +#undef nativeFetchThenSubtract64 +#undef nativeIncrementThenFetch64 +#undef nativeDecrementThenFetch64 +#undef nativeAddThenFetch64 +#undef nativeSubtractThenFetch64 - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); +/* + If any of the operations are not provided then we must emulate some + of them. That means we need a nice implementation of spin locks + that avoids the "one big lock" problem. We use a vector of spin + locks and pick which one to use based on the address of the operand + of the function. + + To generate the index of the lock we first shift by 3 bits to get + rid on the zero bits that result from 32 and 64 bit allignment of + data. We then mask off all but 5 bits and use those 5 bits as an + index into the table. + + Picking the lock this way insures that accesses to the same data at + the same time will go to the same lock. OTOH, accesses to different + data have only a 1/32 chance of hitting the same lock. That should + pretty much eliminate the chances of several atomic operations on + different data from waiting on the same "big lock". If it isn't + then the table of locks can be expanded to a new size so long as + the new size if a power of two. +*/ - return tmp; -#endif -} +static SDL_SpinLock locks[32] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, +}; -Uint16 -SDL_AtomicIncrementThenFetch16(volatile Uint16 * ptr) +static __inline__ void +privateWaitLock(volatile void *ptr) { -#ifdef nativeIncrementThenFetch16 - return nativeIncrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} -Uint16 -SDL_AtomicDecrementThenFetch16(volatile Uint16 * ptr) -{ -#ifdef nativeDecrementThenFetch16 - return nativeDecrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif + SDL_AtomicLock(&locks[index]); } -Uint16 -SDL_AtomicAddThenFetch16(volatile Uint16 * ptr, Uint16 value) +static __inline__ void +privateUnlock(volatile void *ptr) { -#ifdef nativeAddThenFetch16 - return nativeAddThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} - -Uint16 -SDL_AtomicSubtractThenFetch16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeSubtractThenFetch16 - return nativeSubtractThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - return tmp; -#endif + SDL_AtomicUnlock(&locks[index]); } /* 32 bit atomic operations */ -Uint32 -SDL_AtomicExchange32(volatile Uint32 * ptr, Uint32 value) -{ -#ifdef nativeExchange32 - return nativeExchange32(ptr, value); -#else - Uint32 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet32(volatile Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue) -{ -#ifdef nativeCompareThenSet32 - return (SDL_bool)nativeCompareThenSet32(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet32(volatile Uint32 * ptr) { #ifdef nativeTestThenSet32 - return (SDL_bool)nativeTestThenSet32(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -643,11 +166,10 @@ void SDL_AtomicClear32(volatile Uint32 * ptr) { #ifdef nativeClear32 - nativeClear32(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -657,14 +179,13 @@ Uint32 SDL_AtomicFetchThenIncrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenIncrement32 - return nativeFetchThenIncrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -674,14 +195,13 @@ Uint32 SDL_AtomicFetchThenDecrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenDecrement32 - return nativeFetchThenDecrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -691,14 +211,13 @@ Uint32 SDL_AtomicFetchThenAdd32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenAdd32 - return nativeFetchThenAdd32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -708,14 +227,13 @@ Uint32 SDL_AtomicFetchThenSubtract32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenSubtract32 - return nativeFetchThenSubtract32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -725,14 +243,13 @@ Uint32 SDL_AtomicIncrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeIncrementThenFetch32 - return nativeIncrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -742,14 +259,13 @@ Uint32 SDL_AtomicDecrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeDecrementThenFetch32 - return nativeDecrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -759,14 +275,13 @@ Uint32 SDL_AtomicAddThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeAddThenFetch32 - return nativeAddThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -776,14 +291,13 @@ Uint32 SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeSubtractThenFetch32 - return nativeSubtractThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -792,58 +306,20 @@ SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) /* 64 bit atomic operations */ #ifdef SDL_HAS_64BIT_TYPE -Uint64 -SDL_AtomicExchange64(volatile Uint64 * ptr, Uint64 value) -{ -#ifdef nativeExchange64 - return nativeExchange64(ptr, value); -#else - Uint64 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet64(volatile Uint64 * ptr, Uint64 oldvalue, Uint64 newvalue) -{ -#ifdef nativeCompareThenSet64 - return (SDL_bool)nativeCompareThenSet64(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet64(volatile Uint64 * ptr) { #ifdef nativeTestThenSet64 - return (SDL_bool)nativeTestThenSet64(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -853,11 +329,10 @@ void SDL_AtomicClear64(volatile Uint64 * ptr) { #ifdef nativeClear64 - nativeClear64(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -867,14 +342,13 @@ Uint64 SDL_AtomicFetchThenIncrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenIncrement64 - return nativeFetchThenIncrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -884,14 +358,13 @@ Uint64 SDL_AtomicFetchThenDecrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenDecrement64 - return nativeFetchThenDecrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -901,14 +374,13 @@ Uint64 SDL_AtomicFetchThenAdd64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenAdd64 - return nativeFetchThenAdd64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -918,14 +390,13 @@ Uint64 SDL_AtomicFetchThenSubtract64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenSubtract64 - return nativeFetchThenSubtract64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -935,14 +406,13 @@ Uint64 SDL_AtomicIncrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeIncrementThenFetch64 - return nativeIncrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -952,14 +422,13 @@ Uint64 SDL_AtomicDecrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeDecrementThenFetch64 - return nativeDecrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -969,14 +438,13 @@ Uint64 SDL_AtomicAddThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeAddThenFetch64 - return nativeAddThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -986,14 +454,13 @@ Uint64 SDL_AtomicSubtractThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeSubtractThenFetch64 - return nativeSubtractThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif diff --git a/src/atomic/linux/SDL_atomic.c b/src/atomic/linux/SDL_atomic.c index 094e49666..5050191d4 100644 --- a/src/atomic/linux/SDL_atomic.c +++ b/src/atomic/linux/SDL_atomic.c @@ -1,611 +1,167 @@ /* - SDL - Simple DirectMedia Layer - Copyright (C) 1997-2009 Sam Lantinga + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2009 Sam Lantinga - This library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - Sam Lantinga - slouken@libsdl.org + Sam Lantinga + slouken@libsdl.org + + Contributed by Bob Pendleton, bob@pendleton.com */ #include "SDL_stdinc.h" #include "SDL_atomic.h" +#include "SDL_error.h" + /* - This file provides 8, 16, 32, and 64 bit atomic operations. If the + This file provides 32, and 64 bit atomic operations. If the operations are provided by the native hardware and operating system they are used. If they are not then the operations are emulated - using the SDL mutex operations. - */ - -/* - First, detect whether the operations are supported and create - #defines that indicate that they do exist. The goal is to have all - the system dependent code in the top part of the file so that the - bottom can be use unchanged across all platforms. - - Second, #define all the operations in each size class that are - supported. Doing this allows supported operations to be used along - side of emulated operations. + using the SDL spin lock operations. If spin lock can not be + implemented then these functions must fail. */ /* - Linux version. - - Test for gnu C builtin support for atomic operations. The only way - I know of is to check to see if the - __GCC_HAVE_SYNC_COMPARE_AND_SWAP_* macros are defined. - */ - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 -#define HAVE_ALL_8_BIT_OPS - -#define nativeExchange8(ptr, value) (__sync_lock_test_and_set(ptr, value)) -#define nativeCompareThenSet8(ptr, oldvalue, newvalue) (oldvalue == __sync_val_compare_and_swap(ptr, oldvalue, newvalue)) -#define nativeTestThenSet8(ptr) (0 == __sync_lock_test_and_set(ptr, 1)) -#define nativeClear8(ptr) (__sync_lock_release(ptr)) -#define nativeFetchThenIncrement8(ptr) (__sync_fetch_and_add(ptr, 1)) -#define nativeFetchThenDecrement8(ptr) (__sync_fetch_and_sub(ptr, 1)) -#define nativeFetchThenAdd8(ptr, value) (__sync_fetch_and_add(ptr, value)) -#define nativeFetchThenSubtract8(ptr, value) (__sync_fetch_and_sub(ptr, value)) -#define nativeIncrementThenFetch8(ptr) (__sync_add_and_fetch(ptr, 1)) -#define nativeDecrementThenFetch8(ptr) (__sync_sub_and_fetch(ptr, 1)) -#define nativeAddThenFetch8(ptr, value) (__sync_add_and_fetch(ptr, value)) -#define nativeSubtractThenFetch8(ptr, value) (__sync_sub_and_fetch(ptr, value)) -#endif - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 -#define HAVE_ALL_16_BIT_OPS - -#define nativeExchange16(ptr, value) (__sync_lock_test_and_set(ptr, value)) -#define nativeCompareThenSet16(ptr, oldvalue, newvalue) (oldvalue == __sync_val_compare_and_swap(ptr, oldvalue, newvalue)) -#define nativeTestThenSet16(ptr) (0 == __sync_lock_test_and_set(ptr, 1)) -#define nativeClear16(ptr) (__sync_lock_release(ptr)) -#define nativeFetchThenIncrement16(ptr) (__sync_fetch_and_add(ptr, 1)) -#define nativeFetchThenDecrement16(ptr) (__sync_fetch_and_sub(ptr, 1)) -#define nativeFetchThenAdd16(ptr, value) (__sync_fetch_and_add(ptr, value)) -#define nativeFetchThenSubtract16(ptr, value) (__sync_fetch_and_sub(ptr, value)) -#define nativeIncrementThenFetch16(ptr) (__sync_add_and_fetch(ptr, 1)) -#define nativeDecrementThenFetch16(ptr) (__sync_sub_and_fetch(ptr, 1)) -#define nativeAddThenFetch16(ptr, value) (__sync_add_and_fetch(ptr, value)) -#define nativeSubtractThenFetch16(ptr, value) (__sync_sub_and_fetch(ptr, value)) -#endif - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 -#define HAVE_ALL_32_BIT_OPS - -#define nativeExchange32(ptr, value) (__sync_lock_test_and_set(ptr, value)) -#define nativeCompareThenSet32(ptr, oldvalue, newvalue) (oldvalue == __sync_val_compare_and_swap(ptr, oldvalue, newvalue)) -#define nativeTestThenSet32(ptr) (0 == __sync_lock_test_and_set(ptr, 1)) -#define nativeClear32(ptr) (__sync_lock_release(ptr)) -#define nativeFetchThenIncrement32(ptr) (__sync_fetch_and_add(ptr, 1)) -#define nativeFetchThenDecrement32(ptr) (__sync_fetch_and_sub(ptr, 1)) -#define nativeFetchThenAdd32(ptr, value) (__sync_fetch_and_add(ptr, value)) -#define nativeFetchThenSubtract32(ptr, value) (__sync_fetch_and_sub(ptr, value)) -#define nativeIncrementThenFetch32(ptr) (__sync_add_and_fetch(ptr, 1)) -#define nativeDecrementThenFetch32(ptr) (__sync_sub_and_fetch(ptr, 1)) -#define nativeAddThenFetch32(ptr, value) (__sync_add_and_fetch(ptr, value)) -#define nativeSubtractThenFetch32(ptr, value) (__sync_sub_and_fetch(ptr, value)) -#endif - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 -#define HAVE_ALL_64_BIT_OPS - -#define nativeExchange64(ptr, value) (__sync_lock_test_and_set(ptr, value)) -#define nativeCompareThenSet64(ptr, oldvalue, newvalue) (oldvalue == __sync_val_compare_and_swap(ptr, oldvalue, newvalue)) -#define nativeTestThenSet64(ptr) (0 == __sync_lock_test_and_set(ptr, 1)) -#define nativeClear64(ptr) (__sync_lock_release(ptr)) -#define nativeFetchThenIncrement64(ptr) (__sync_fetch_and_add(ptr, 1)) -#define nativeFetchThenDecrement64(ptr) (__sync_fetch_and_sub(ptr, 1)) -#define nativeFetchThenAdd64(ptr, value) (__sync_fetch_and_add(ptr, value)) -#define nativeFetchThenSubtract64(ptr, value) (__sync_fetch_and_sub(ptr, value)) -#define nativeIncrementThenFetch64(ptr) (__sync_add_and_fetch(ptr, 1)) -#define nativeDecrementThenFetch64(ptr) (__sync_sub_and_fetch(ptr, 1)) -#define nativeAddThenFetch64(ptr, value) (__sync_add_and_fetch(ptr, value)) -#define nativeSubtractThenFetch64(ptr, value) (__sync_sub_and_fetch(ptr, value)) -#endif - -/* -If any of the operations are not provided then we must emulate some of -them. - */ - -#if !defined(HAVE_ALL_8_BIT_OPS) || !defined(HAVE_ALL_16_BIT_OPS) || !defined(HAVE_ALL_32_BIT_OPS) || !defined(HAVE_ALL_64_BIT_OPS) - -static Uint32 lock = 0; + LINUX/GCC VERSION. -#define privateWaitLock() \ - while (nativeTestThenSet32(&lock)) \ - { \ - }; - -#define privateUnlock() (nativeClear32(&lock)) -#endif - -/* 8 bit atomic operations */ - -Uint8 -SDL_AtomicExchange8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeExchange8 - return nativeExchange8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet8(volatile Uint8 * ptr, Uint8 oldvalue, Uint8 newvalue) -{ -#ifdef nativeCompareThenSet8 - return (SDL_bool)nativeCompareThenSet8(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet8(volatile Uint8 * ptr) -{ -#ifdef nativeTestThenSet8 - return (SDL_bool)nativeTestThenSet8(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear8(volatile Uint8 * ptr) -{ -#ifdef nativeClear8 - nativeClear8(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); - - return; -#endif -} - -Uint8 -SDL_AtomicFetchThenIncrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenIncrement8 - return nativeFetchThenIncrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenDecrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenDecrement8 - return nativeFetchThenDecrement8(ptr); -#else - Uint8 tmp = 0; + This version of the code assumes support of the atomic builtins as + documented at gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html This + code should work on any modern x86 or other processor supported by + GCC. - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenAdd8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenAdd8 - return nativeFetchThenAdd8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenSubtract8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenSubtract8 - return nativeFetchThenSubtract8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicIncrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeIncrementThenFetch8 - return nativeIncrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicDecrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeDecrementThenFetch8 - return nativeDecrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicAddThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeAddThenFetch8 - return nativeAddThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicSubtractThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeSubtractThenFetch8 - return nativeSubtractThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -/* 16 bit atomic operations */ - -Uint16 -SDL_AtomicExchange16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeExchange16 - return nativeExchange16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet16(volatile Uint16 * ptr, Uint16 oldvalue, Uint16 newvalue) -{ -#ifdef nativeCompareThenSet16 - return (SDL_bool)nativeCompareThenSet16(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); + Some processors will only support some of these operations so + #ifdefs will have to be added as incompatibilities are discovered +*/ - return result; -#endif -} +/* + Native spinlock routines. +*/ -SDL_bool -SDL_AtomicTestThenSet16(volatile Uint16 * ptr) +void +SDL_AtomicLock(SDL_SpinLock *lock) { -#ifdef nativeTestThenSet16 - return (SDL_bool)nativeTestThenSet16(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) + while (0 != __sync_lock_test_and_set(lock, 1)) { - *ptr = 1; } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear16(volatile Uint16 * ptr) -{ -#ifdef nativeClear16 - nativeClear16(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); - - return; -#endif -} - -Uint16 -SDL_AtomicFetchThenIncrement16(volatile Uint16 * ptr) -{ -#ifdef nativeFetchThenIncrement16 - return nativeFetchThenIncrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif } -Uint16 -SDL_AtomicFetchThenDecrement16(volatile Uint16 * ptr) +void +SDL_AtomicUnlock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenDecrement16 - return nativeFetchThenDecrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif + __sync_lock_test_and_set(lock, 0); } -Uint16 -SDL_AtomicFetchThenAdd16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenAdd16 - return nativeFetchThenAdd16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} +/* + Note that platform specific versions can be built from this version + by changing the #undefs to #defines and adding platform specific + code. +*/ -Uint16 -SDL_AtomicFetchThenSubtract16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenSubtract16 - return nativeFetchThenSubtract16(ptr, value); -#else - Uint16 tmp = 0; +#define nativeTestThenSet32 +#define nativeClear32 +#define nativeFetchThenIncrement32 +#define nativeFetchThenDecrement32 +#define nativeFetchThenAdd32 +#define nativeFetchThenSubtract32 +#define nativeIncrementThenFetch32 +#define nativeDecrementThenFetch32 +#define nativeAddThenFetch32 +#define nativeSubtractThenFetch32 + +#define nativeTestThenSet64 +#define nativeClear64 +#define nativeFetchThenIncrement64 +#define nativeFetchThenDecrement64 +#define nativeFetchThenAdd64 +#define nativeFetchThenSubtract64 +#define nativeIncrementThenFetch64 +#define nativeDecrementThenFetch64 +#define nativeAddThenFetch64 +#define nativeSubtractThenFetch64 - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); +/* + If any of the operations are not provided then we must emulate some + of them. That means we need a nice implementation of spin locks + that avoids the "one big lock" problem. We use a vector of spin + locks and pick which one to use based on the address of the operand + of the function. + + To generate the index of the lock we first shift by 3 bits to get + rid on the zero bits that result from 32 and 64 bit allignment of + data. We then mask off all but 5 bits and use those 5 bits as an + index into the table. + + Picking the lock this way insures that accesses to the same data at + the same time will go to the same lock. OTOH, accesses to different + data have only a 1/32 chance of hitting the same lock. That should + pretty much eliminate the chances of several atomic operations on + different data from waiting on the same "big lock". If it isn't + then the table of locks can be expanded to a new size so long as + the new size if a power of two. +*/ - return tmp; -#endif -} +static SDL_SpinLock locks[32] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, +}; -Uint16 -SDL_AtomicIncrementThenFetch16(volatile Uint16 * ptr) +static __inline__ void +privateWaitLock(volatile void *ptr) { -#ifdef nativeIncrementThenFetch16 - return nativeIncrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} - -Uint16 -SDL_AtomicDecrementThenFetch16(volatile Uint16 * ptr) -{ -#ifdef nativeDecrementThenFetch16 - return nativeDecrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif + SDL_AtomicLock(&locks[index]); } -Uint16 -SDL_AtomicAddThenFetch16(volatile Uint16 * ptr, Uint16 value) +static __inline__ void +privateUnlock(volatile void *ptr) { -#ifdef nativeAddThenFetch16 - return nativeAddThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} - -Uint16 -SDL_AtomicSubtractThenFetch16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeSubtractThenFetch16 - return nativeSubtractThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif + SDL_AtomicUnlock(&locks[index]); } /* 32 bit atomic operations */ -Uint32 -SDL_AtomicExchange32(volatile Uint32 * ptr, Uint32 value) -{ -#ifdef nativeExchange32 - return nativeExchange32(ptr, value); -#else - Uint32 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet32(volatile Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue) -{ -#ifdef nativeCompareThenSet32 - return (SDL_bool)nativeCompareThenSet32(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet32(volatile Uint32 * ptr) { #ifdef nativeTestThenSet32 - return (SDL_bool)nativeTestThenSet32(ptr); + return 0 == __sync_lock_test_and_set(ptr, 1); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -615,11 +171,12 @@ void SDL_AtomicClear32(volatile Uint32 * ptr) { #ifdef nativeClear32 - nativeClear32(ptr); + __sync_lock_test_and_set(ptr, 0); + return; #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -629,14 +186,14 @@ Uint32 SDL_AtomicFetchThenIncrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenIncrement32 - return nativeFetchThenIncrement32(ptr); + return __sync_fetch_and_add(ptr, 1); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -646,14 +203,14 @@ Uint32 SDL_AtomicFetchThenDecrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenDecrement32 - return nativeFetchThenDecrement32(ptr); + return __sync_fetch_and_sub(ptr, 1); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -663,14 +220,14 @@ Uint32 SDL_AtomicFetchThenAdd32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenAdd32 - return nativeFetchThenAdd32(ptr, value); + return __sync_fetch_and_add(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -680,14 +237,14 @@ Uint32 SDL_AtomicFetchThenSubtract32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenSubtract32 - return nativeFetchThenSubtract32(ptr, value); + return __sync_fetch_and_sub(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -697,14 +254,14 @@ Uint32 SDL_AtomicIncrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeIncrementThenFetch32 - return nativeIncrementThenFetch32(ptr); + return __sync_add_and_fetch(ptr, 1); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -714,14 +271,14 @@ Uint32 SDL_AtomicDecrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeDecrementThenFetch32 - return nativeDecrementThenFetch32(ptr); + return __sync_sub_and_fetch(ptr, 1); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -731,14 +288,14 @@ Uint32 SDL_AtomicAddThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeAddThenFetch32 - return nativeAddThenFetch32(ptr, value); + return __sync_add_and_fetch(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -748,14 +305,14 @@ Uint32 SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeSubtractThenFetch32 - return nativeSubtractThenFetch32(ptr, value); + return __sync_sub_and_fetch(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -764,58 +321,21 @@ SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) /* 64 bit atomic operations */ #ifdef SDL_HAS_64BIT_TYPE -Uint64 -SDL_AtomicExchange64(volatile Uint64 * ptr, Uint64 value) -{ -#ifdef nativeExchange64 - return nativeExchange64(ptr, value); -#else - Uint64 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet64(volatile Uint64 * ptr, Uint64 oldvalue, Uint64 newvalue) -{ -#ifdef nativeCompareThenSet64 - return (SDL_bool)nativeCompareThenSet64(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet64(volatile Uint64 * ptr) { #ifdef nativeTestThenSet64 - return (SDL_bool)nativeTestThenSet64(ptr); + return 0 == __sync_lock_test_and_set(ptr, 1); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -825,11 +345,12 @@ void SDL_AtomicClear64(volatile Uint64 * ptr) { #ifdef nativeClear64 - nativeClear64(ptr); + __sync_lock_test_and_set(ptr, 0); + return; #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -839,14 +360,14 @@ Uint64 SDL_AtomicFetchThenIncrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenIncrement64 - return nativeFetchThenIncrement64(ptr); + return __sync_fetch_and_add(ptr, 1); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -856,14 +377,14 @@ Uint64 SDL_AtomicFetchThenDecrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenDecrement64 - return nativeFetchThenDecrement64(ptr); + return __sync_fetch_and_sub(ptr, 1); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -873,14 +394,14 @@ Uint64 SDL_AtomicFetchThenAdd64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenAdd64 - return nativeFetchThenAdd64(ptr, value); + return __sync_fetch_and_add(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -890,14 +411,14 @@ Uint64 SDL_AtomicFetchThenSubtract64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenSubtract64 - return nativeFetchThenSubtract64(ptr, value); + return __sync_fetch_and_sub(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -907,14 +428,14 @@ Uint64 SDL_AtomicIncrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeIncrementThenFetch64 - return nativeIncrementThenFetch64(ptr); + return __sync_add_and_fetch(ptr, 1); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -924,14 +445,14 @@ Uint64 SDL_AtomicDecrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeDecrementThenFetch64 - return nativeDecrementThenFetch64(ptr); + return __sync_sub_and_fetch(ptr, 1); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -941,14 +462,14 @@ Uint64 SDL_AtomicAddThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeAddThenFetch64 - return nativeAddThenFetch64(ptr, value); + return __sync_add_and_fetch(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -958,17 +479,17 @@ Uint64 SDL_AtomicSubtractThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeSubtractThenFetch64 - return nativeSubtractThenFetch64(ptr, value); + return __sync_sub_and_fetch(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } -#endif +#endif /* SDL_HAS_64BIT_TYPE */ diff --git a/src/atomic/macosx/SDL_atomic.c b/src/atomic/macosx/SDL_atomic.c index de3e52170..b2a7e7a7c 100644 --- a/src/atomic/macosx/SDL_atomic.c +++ b/src/atomic/macosx/SDL_atomic.c @@ -1,639 +1,162 @@ /* - SDL - Simple DirectMedia Layer - Copyright (C) 1997-2009 Sam Lantinga + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2009 Sam Lantinga - This library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - Sam Lantinga - slouken@libsdl.org + Sam Lantinga + slouken@libsdl.org + + Contributed by Bob Pendleton, bob@pendleton.com */ #include "SDL_stdinc.h" #include "SDL_atomic.h" +#include "SDL_error.h" + /* - This file provides 8, 16, 32, and 64 bit atomic operations. If the + This file provides 32, and 64 bit atomic operations. If the operations are provided by the native hardware and operating system they are used. If they are not then the operations are emulated - using the SDL mutex operations. - */ - -/* - First, detect whether the operations are supported and create - #defines that indicate that they do exist. The goal is to have all - the system dependent code in the top part of the file so that the - bottom can be use unchanged across all platforms. - - Second, #define all the operations in each size class that are - supported. Doing this allows supported operations to be used along - side of emulated operations. + using the SDL spin lock operations. If spin lock can not be + implemented then these functions must fail. */ /* - Emmulated version. - - Assume there is no support for atomic operations. All such - operations are implemented using SDL mutex operations. - */ - -#ifdef EMULATED_ATOMIC_OPERATIONS -#undef EMULATED_ATOMIC_OPERATIONS -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_8_BIT_OPS - -#define nativeExchange8(ptr, value) () -#define nativeCompareThenSet8(ptr, oldvalue, newvalue) () -#define nativeTestThenSet8(ptr) () -#define nativeClear8(ptr) () -#define nativeFetchThenIncrement8(ptr) () -#define nativeFetchThenDecrement8(ptr) () -#define nativeFetchThenAdd8(ptr, value) () -#define nativeFetchThenSubtract8(ptr, value) () -#define nativeIncrementThenFetch8(ptr) () -#define nativeDecrementThenFetch8(ptr) () -#define nativeAddThenFetch8(ptr, value) () -#define nativeSubtractThenFetch8(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_16_BIT_OPS - -#define nativeExchange16(ptr, value) () -#define nativeCompareThenSet16(ptr, oldvalue, newvalue) () -#define nativeTestThenSet16(ptr) () -#define nativeClear16(ptr) () -#define nativeFetchThenIncrement16(ptr) () -#define nativeFetchThenDecrement16(ptr) () -#define nativeFetchThenAdd16(ptr, value) () -#define nativeFetchThenSubtract16(ptr, value) () -#define nativeIncrementThenFetch16(ptr) () -#define nativeDecrementThenFetch16(ptr) () -#define nativeAddThenFetch16(ptr, value) () -#define nativeSubtractThenFetch16(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_32_BIT_OPS - -#define nativeExchange32(ptr, value) () -#define nativeCompareThenSet32(ptr, oldvalue, newvalue) () -#define nativeTestThenSet32(ptr) () -#define nativeClear32(ptr) () -#define nativeFetchThenIncrement32(ptr) () -#define nativeFetchThenDecrement32(ptr) () -#define nativeFetchThenAdd32(ptr, value) () -#define nativeFetchThenSubtract32(ptr, value) () -#define nativeIncrementThenFetch32(ptr) () -#define nativeDecrementThenFetch32(ptr) () -#define nativeAddThenFetch32(ptr, value) () -#define nativeSubtractThenFetch32(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_64_BIT_OPS - -#define nativeExchange64(ptr, value) () -#define nativeCompareThenSet64(ptr, oldvalue, newvalue) () -#define nativeTestThenSet64(ptr) () -#define nativeClear64(ptr) () -#define nativeFetchThenIncrement64(ptr) () -#define nativeFetchThenDecrement64(ptr) () -#define nativeFetchThenAdd64(ptr, value) () -#define nativeFetchThenSubtract64(ptr, value) () -#define nativeIncrementThenFetch64(ptr) () -#define nativeDecrementThenFetch64(ptr) () -#define nativeAddThenFetch64(ptr, value) () -#define nativeSubtractThenFetch64(ptr, value) () -#endif - -/* -If any of the operations are not provided then we must emulate some of -them. - */ - -#if !defined(HAVE_ALL_8_BIT_OPS) || !defined(HAVE_ALL_16_BIT_OPS) || !defined(HAVE_ALL_32_BIT_OPS) || !defined(HAVE_ALL_64_BIT_OPS) - -#include "SDL_mutex.h" -#include "SDL_error.h" - -static SDL_mutex * lock = NULL; - -static __inline__ void -privateWaitLock() -{ - if(NULL == lock) - { - lock = SDL_CreateMutex(); - if (NULL == lock) - { - SDL_SetError("SDL_atomic.c: can't create a mutex"); - return; - } - } - - if (-1 == SDL_LockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't lock mutex"); - } -} - -static __inline__ void -privateUnlock() -{ - if (-1 == SDL_UnlockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't unlock mutex"); - } -} - -#endif - -/* 8 bit atomic operations */ - -Uint8 -SDL_AtomicExchange8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeExchange8 - return nativeExchange8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet8(volatile Uint8 * ptr, Uint8 oldvalue, Uint8 newvalue) -{ -#ifdef nativeCompareThenSet8 - return (SDL_bool)nativeCompareThenSet8(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet8(volatile Uint8 * ptr) -{ -#ifdef nativeTestThenSet8 - return (SDL_bool)nativeTestThenSet8(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear8(volatile Uint8 * ptr) -{ -#ifdef nativeClear8 - nativeClear8(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); - - return; -#endif -} - -Uint8 -SDL_AtomicFetchThenIncrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenIncrement8 - return nativeFetchThenIncrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenDecrement8(volatile Uint8 * ptr) -{ -#ifdef nativeFetchThenDecrement8 - return nativeFetchThenDecrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenAdd8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenAdd8 - return nativeFetchThenAdd8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenSubtract8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenSubtract8 - return nativeFetchThenSubtract8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicIncrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeIncrementThenFetch8 - return nativeIncrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicDecrementThenFetch8(volatile Uint8 * ptr) -{ -#ifdef nativeDecrementThenFetch8 - return nativeDecrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicAddThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeAddThenFetch8 - return nativeAddThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicSubtractThenFetch8(volatile Uint8 * ptr, Uint8 value) -{ -#ifdef nativeSubtractThenFetch8 - return nativeSubtractThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -/* 16 bit atomic operations */ - -Uint16 -SDL_AtomicExchange16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeExchange16 - return nativeExchange16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet16(volatile Uint16 * ptr, Uint16 oldvalue, Uint16 newvalue) -{ -#ifdef nativeCompareThenSet16 - return (SDL_bool)nativeCompareThenSet16(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); + DUMMY VERSION. - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet16(volatile Uint16 * ptr) -{ -#ifdef nativeTestThenSet16 - return (SDL_bool)nativeTestThenSet16(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear16(volatile Uint16 * ptr) -{ -#ifdef nativeClear16 - nativeClear16(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); + This version of the code assumes there is no support for atomic + operations. Therefore, every function sets the SDL error + message. Oddly enough, if you only have one thread then this + version actuallys works. +*/ - return; -#endif -} +/* + Native spinlock routines. Because this is the dummy implementation + these will always call SDL_SetError() and do nothing. +*/ -Uint16 -SDL_AtomicFetchThenIncrement16(volatile Uint16 * ptr) +void +SDL_AtomicLock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenIncrement16 - return nativeFetchThenIncrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenDecrement16(volatile Uint16 * ptr) +void +SDL_AtomicUnlock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenDecrement16 - return nativeFetchThenDecrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenAdd16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenAdd16 - return nativeFetchThenAdd16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} +/* + Note that platform specific versions can be built from this version + by changing the #undefs to #defines and adding platform specific + code. +*/ -Uint16 -SDL_AtomicFetchThenSubtract16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenSubtract16 - return nativeFetchThenSubtract16(ptr, value); -#else - Uint16 tmp = 0; +#undef nativeTestThenSet32 +#undef nativeClear32 +#undef nativeFetchThenIncrement32 +#undef nativeFetchThenDecrement32 +#undef nativeFetchThenAdd32 +#undef nativeFetchThenSubtract32 +#undef nativeIncrementThenFetch32 +#undef nativeDecrementThenFetch32 +#undef nativeAddThenFetch32 +#undef nativeSubtractThenFetch32 + +#undef nativeTestThenSet64 +#undef nativeClear64 +#undef nativeFetchThenIncrement64 +#undef nativeFetchThenDecrement64 +#undef nativeFetchThenAdd64 +#undef nativeFetchThenSubtract64 +#undef nativeIncrementThenFetch64 +#undef nativeDecrementThenFetch64 +#undef nativeAddThenFetch64 +#undef nativeSubtractThenFetch64 - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); +/* + If any of the operations are not provided then we must emulate some + of them. That means we need a nice implementation of spin locks + that avoids the "one big lock" problem. We use a vector of spin + locks and pick which one to use based on the address of the operand + of the function. + + To generate the index of the lock we first shift by 3 bits to get + rid on the zero bits that result from 32 and 64 bit allignment of + data. We then mask off all but 5 bits and use those 5 bits as an + index into the table. + + Picking the lock this way insures that accesses to the same data at + the same time will go to the same lock. OTOH, accesses to different + data have only a 1/32 chance of hitting the same lock. That should + pretty much eliminate the chances of several atomic operations on + different data from waiting on the same "big lock". If it isn't + then the table of locks can be expanded to a new size so long as + the new size if a power of two. +*/ - return tmp; -#endif -} +static SDL_SpinLock locks[32] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, +}; -Uint16 -SDL_AtomicIncrementThenFetch16(volatile Uint16 * ptr) +static __inline__ void +privateWaitLock(volatile void *ptr) { -#ifdef nativeIncrementThenFetch16 - return nativeIncrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} -Uint16 -SDL_AtomicDecrementThenFetch16(volatile Uint16 * ptr) -{ -#ifdef nativeDecrementThenFetch16 - return nativeDecrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif + SDL_AtomicLock(&locks[index]); } -Uint16 -SDL_AtomicAddThenFetch16(volatile Uint16 * ptr, Uint16 value) +static __inline__ void +privateUnlock(volatile void *ptr) { -#ifdef nativeAddThenFetch16 - return nativeAddThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} - -Uint16 -SDL_AtomicSubtractThenFetch16(volatile Uint16 * ptr, Uint16 value) -{ -#ifdef nativeSubtractThenFetch16 - return nativeSubtractThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - return tmp; -#endif + SDL_AtomicUnlock(&locks[index]); } /* 32 bit atomic operations */ -Uint32 -SDL_AtomicExchange32(volatile Uint32 * ptr, Uint32 value) -{ -#ifdef nativeExchange32 - return nativeExchange32(ptr, value); -#else - Uint32 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet32(volatile Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue) -{ -#ifdef nativeCompareThenSet32 - return (SDL_bool)nativeCompareThenSet32(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet32(volatile Uint32 * ptr) { #ifdef nativeTestThenSet32 - return (SDL_bool)nativeTestThenSet32(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -643,11 +166,10 @@ void SDL_AtomicClear32(volatile Uint32 * ptr) { #ifdef nativeClear32 - nativeClear32(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -657,14 +179,13 @@ Uint32 SDL_AtomicFetchThenIncrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenIncrement32 - return nativeFetchThenIncrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -674,14 +195,13 @@ Uint32 SDL_AtomicFetchThenDecrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenDecrement32 - return nativeFetchThenDecrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -691,14 +211,13 @@ Uint32 SDL_AtomicFetchThenAdd32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenAdd32 - return nativeFetchThenAdd32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -708,14 +227,13 @@ Uint32 SDL_AtomicFetchThenSubtract32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenSubtract32 - return nativeFetchThenSubtract32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -725,14 +243,13 @@ Uint32 SDL_AtomicIncrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeIncrementThenFetch32 - return nativeIncrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -742,14 +259,13 @@ Uint32 SDL_AtomicDecrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeDecrementThenFetch32 - return nativeDecrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -759,14 +275,13 @@ Uint32 SDL_AtomicAddThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeAddThenFetch32 - return nativeAddThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -776,14 +291,13 @@ Uint32 SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeSubtractThenFetch32 - return nativeSubtractThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -792,58 +306,20 @@ SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) /* 64 bit atomic operations */ #ifdef SDL_HAS_64BIT_TYPE -Uint64 -SDL_AtomicExchange64(volatile Uint64 * ptr, Uint64 value) -{ -#ifdef nativeExchange64 - return nativeExchange64(ptr, value); -#else - Uint64 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet64(volatile Uint64 * ptr, Uint64 oldvalue, Uint64 newvalue) -{ -#ifdef nativeCompareThenSet64 - return (SDL_bool)nativeCompareThenSet64(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool SDL_AtomicTestThenSet64(volatile Uint64 * ptr) { #ifdef nativeTestThenSet64 - return (SDL_bool)nativeTestThenSet64(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif @@ -853,11 +329,10 @@ void SDL_AtomicClear64(volatile Uint64 * ptr) { #ifdef nativeClear64 - nativeClear64(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif @@ -867,14 +342,13 @@ Uint64 SDL_AtomicFetchThenIncrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenIncrement64 - return nativeFetchThenIncrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -884,14 +358,13 @@ Uint64 SDL_AtomicFetchThenDecrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenDecrement64 - return nativeFetchThenDecrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -901,14 +374,13 @@ Uint64 SDL_AtomicFetchThenAdd64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenAdd64 - return nativeFetchThenAdd64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -918,14 +390,13 @@ Uint64 SDL_AtomicFetchThenSubtract64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenSubtract64 - return nativeFetchThenSubtract64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -935,14 +406,13 @@ Uint64 SDL_AtomicIncrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeIncrementThenFetch64 - return nativeIncrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -952,14 +422,13 @@ Uint64 SDL_AtomicDecrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeDecrementThenFetch64 - return nativeDecrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -969,14 +438,13 @@ Uint64 SDL_AtomicAddThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeAddThenFetch64 - return nativeAddThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -986,14 +454,13 @@ Uint64 SDL_AtomicSubtractThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeSubtractThenFetch64 - return nativeSubtractThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif diff --git a/src/atomic/win32/SDL_atomic.c b/src/atomic/win32/SDL_atomic.c index c97f6ba1a..b2a7e7a7c 100644 --- a/src/atomic/win32/SDL_atomic.c +++ b/src/atomic/win32/SDL_atomic.c @@ -1,789 +1,303 @@ /* - SDL - Simple DirectMedia Layer - Copyright (C) 1997-2009 Sam Lantinga + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2009 Sam Lantinga - This library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - Sam Lantinga - slouken@libsdl.org + Sam Lantinga + slouken@libsdl.org + + Contributed by Bob Pendleton, bob@pendleton.com */ #include "SDL_stdinc.h" #include "SDL_atomic.h" +#include "SDL_error.h" + /* - This file provides 8, 16, 32, and 64 bit atomic operations. If the + This file provides 32, and 64 bit atomic operations. If the operations are provided by the native hardware and operating system they are used. If they are not then the operations are emulated - using the SDL mutex operations. - */ - -/* - First, detect whether the operations are supported and create - #defines that indicate that they do exist. The goal is to have all - the system dependent code in the top part of the file so that the - bottom can be use unchanged across all platforms. - - Second, #define all the operations in each size class that are - supported. Doing this allows supported operations to be used along - side of emulated operations. + using the SDL spin lock operations. If spin lock can not be + implemented then these functions must fail. */ /* - Emmulated version. - - Assume there is no support for atomic operations. All such - operations are implemented using SDL mutex operations. - */ - -#ifdef EMULATED_ATOMIC_OPERATIONS -#undef EMULATED_ATOMIC_OPERATIONS -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_8_BIT_OPS - -#define nativeExchange8(ptr, value) () -#define nativeCompareThenSet8(ptr, oldvalue, newvalue) () -#define nativeTestThenSet8(ptr) () -#define nativeClear8(ptr) () -#define nativeFetchThenIncrement8(ptr) () -#define nativeFetchThenDecrement8(ptr) () -#define nativeFetchThenAdd8(ptr, value) () -#define nativeFetchThenSubtract8(ptr, value) () -#define nativeIncrementThenFetch8(ptr) () -#define nativeDecrementThenFetch8(ptr) () -#define nativeAddThenFetch8(ptr, value) () -#define nativeSubtractThenFetch8(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_16_BIT_OPS - -#define nativeExchange16(ptr, value) () -#define nativeCompareThenSet16(ptr, oldvalue, newvalue) () -#define nativeTestThenSet16(ptr) () -#define nativeClear16(ptr) () -#define nativeFetchThenIncrement16(ptr) () -#define nativeFetchThenDecrement16(ptr) () -#define nativeFetchThenAdd16(ptr, value) () -#define nativeFetchThenSubtract16(ptr, value) () -#define nativeIncrementThenFetch16(ptr) () -#define nativeDecrementThenFetch16(ptr) () -#define nativeAddThenFetch16(ptr, value) () -#define nativeSubtractThenFetch16(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_32_BIT_OPS - -#define nativeExchange32(ptr, value) () -#define nativeCompareThenSet32(ptr, oldvalue, newvalue) () -#define nativeTestThenSet32(ptr) () -#define nativeClear32(ptr) () -#define nativeFetchThenIncrement32(ptr) () -#define nativeFetchThenDecrement32(ptr) () -#define nativeFetchThenAdd32(ptr, value) () -#define nativeFetchThenSubtract32(ptr, value) () -#define nativeIncrementThenFetch32(ptr) () -#define nativeDecrementThenFetch32(ptr) () -#define nativeAddThenFetch32(ptr, value) () -#define nativeSubtractThenFetch32(ptr, value) () -#endif - -#ifdef EMULATED_ATOMIC_OPERATIONS -#define HAVE_ALL_64_BIT_OPS - -#define nativeExchange64(ptr, value) () -#define nativeCompareThenSet64(ptr, oldvalue, newvalue) () -#define nativeTestThenSet64(ptr) () -#define nativeClear64(ptr) () -#define nativeFetchThenIncrement64(ptr) () -#define nativeFetchThenDecrement64(ptr) () -#define nativeFetchThenAdd64(ptr, value) () -#define nativeFetchThenSubtract64(ptr, value) () -#define nativeIncrementThenFetch64(ptr) () -#define nativeDecrementThenFetch64(ptr) () -#define nativeAddThenFetch64(ptr, value) () -#define nativeSubtractThenFetch64(ptr, value) () -#endif - -/* -If any of the operations are not provided then we must emulate some of -them. - */ - -#if !defined(HAVE_ALL_8_BIT_OPS) || !defined(HAVE_ALL_16_BIT_OPS) || !defined(HAVE_ALL_32_BIT_OPS) || !defined(HAVE_ALL_64_BIT_OPS) - -#include "SDL_mutex.h" -#include "SDL_error.h" - -static SDL_mutex * lock = NULL; - -static __inline__ void -privateWaitLock() -{ - if(NULL == lock) - { - lock = SDL_CreateMutex(); - if (NULL == lock) - { - SDL_SetError("SDL_atomic.c: can't create a mutex"); - return; - } - } - - if (-1 == SDL_LockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't lock mutex"); - } -} - -static __inline__ void -privateUnlock() -{ - if (-1 == SDL_UnlockMutex(lock)) - { - SDL_SetError("SDL_atomic.c: can't unlock mutex"); - } -} - -#endif - -/* 8 bit atomic operations */ - -Uint8 -SDL_AtomicExchange8(Uint8 * ptr, Uint8 value) -{ -#ifdef nativeExchange8 - return nativeExchange8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet8(Uint8 * ptr, Uint8 oldvalue, Uint8 newvalue) -{ -#ifdef nativeCompareThenSet8 - return (SDL_bool)nativeCompareThenSet8(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet8(Uint8 * ptr) -{ -#ifdef nativeTestThenSet8 - return (SDL_bool)nativeTestThenSet8(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear8(Uint8 * ptr) -{ -#ifdef nativeClear8 - nativeClear8(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); - - return; -#endif -} - -Uint8 -SDL_AtomicFetchThenIncrement8(Uint8 * ptr) -{ -#ifdef nativeFetchThenIncrement8 - return nativeFetchThenIncrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenDecrement8(Uint8 * ptr) -{ -#ifdef nativeFetchThenDecrement8 - return nativeFetchThenDecrement8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenAdd8(Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenAdd8 - return nativeFetchThenAdd8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicFetchThenSubtract8(Uint8 * ptr, Uint8 value) -{ -#ifdef nativeFetchThenSubtract8 - return nativeFetchThenSubtract8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicIncrementThenFetch8(Uint8 * ptr) -{ -#ifdef nativeIncrementThenFetch8 - return nativeIncrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicDecrementThenFetch8(Uint8 * ptr) -{ -#ifdef nativeDecrementThenFetch8 - return nativeDecrementThenFetch8(ptr); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicAddThenFetch8(Uint8 * ptr, Uint8 value) -{ -#ifdef nativeAddThenFetch8 - return nativeAddThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -Uint8 -SDL_AtomicSubtractThenFetch8(Uint8 * ptr, Uint8 value) -{ -#ifdef nativeSubtractThenFetch8 - return nativeSubtractThenFetch8(ptr, value); -#else - Uint8 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif -} - -/* 16 bit atomic operations */ - -Uint16 -SDL_AtomicExchange16(Uint16 * ptr, Uint16 value) -{ -#ifdef nativeExchange16 - return nativeExchange16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet16(Uint16 * ptr, Uint16 oldvalue, Uint16 newvalue) -{ -#ifdef nativeCompareThenSet16 - return (SDL_bool)nativeCompareThenSet16(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); + DUMMY VERSION. - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet16(Uint16 * ptr) -{ -#ifdef nativeTestThenSet16 - return (SDL_bool)nativeTestThenSet16(ptr); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == 0); - if (result) - { - *ptr = 1; - } - privateUnlock(); - - return result; -#endif -} - -void -SDL_AtomicClear16(Uint16 * ptr) -{ -#ifdef nativeClear16 - nativeClear16(ptr); -#else - privateWaitLock(); - *ptr = 0; - privateUnlock(); + This version of the code assumes there is no support for atomic + operations. Therefore, every function sets the SDL error + message. Oddly enough, if you only have one thread then this + version actuallys works. +*/ - return; -#endif -} +/* + Native spinlock routines. Because this is the dummy implementation + these will always call SDL_SetError() and do nothing. +*/ -Uint16 -SDL_AtomicFetchThenIncrement16(Uint16 * ptr) +void +SDL_AtomicLock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenIncrement16 - return nativeFetchThenIncrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenDecrement16(Uint16 * ptr) +void +SDL_AtomicUnlock(SDL_SpinLock *lock) { -#ifdef nativeFetchThenDecrement16 - return nativeFetchThenDecrement16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr) -= 1; - privateUnlock(); - - return tmp; -#endif + SDL_SetError("SDL_atomic.c: is not implemented on this platform"); } -Uint16 -SDL_AtomicFetchThenAdd16(Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenAdd16 - return nativeFetchThenAdd16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - (*ptr)+= value; - privateUnlock(); - - return tmp; -#endif -} +/* + Note that platform specific versions can be built from this version + by changing the #undefs to #defines and adding platform specific + code. +*/ -Uint16 -SDL_AtomicFetchThenSubtract16(Uint16 * ptr, Uint16 value) -{ -#ifdef nativeFetchThenSubtract16 - return nativeFetchThenSubtract16(ptr, value); -#else - Uint16 tmp = 0; +#undef nativeTestThenSet32 +#undef nativeClear32 +#undef nativeFetchThenIncrement32 +#undef nativeFetchThenDecrement32 +#undef nativeFetchThenAdd32 +#undef nativeFetchThenSubtract32 +#undef nativeIncrementThenFetch32 +#undef nativeDecrementThenFetch32 +#undef nativeAddThenFetch32 +#undef nativeSubtractThenFetch32 + +#undef nativeTestThenSet64 +#undef nativeClear64 +#undef nativeFetchThenIncrement64 +#undef nativeFetchThenDecrement64 +#undef nativeFetchThenAdd64 +#undef nativeFetchThenSubtract64 +#undef nativeIncrementThenFetch64 +#undef nativeDecrementThenFetch64 +#undef nativeAddThenFetch64 +#undef nativeSubtractThenFetch64 - privateWaitLock(); - tmp = *ptr; - (*ptr)-= value; - privateUnlock(); +/* + If any of the operations are not provided then we must emulate some + of them. That means we need a nice implementation of spin locks + that avoids the "one big lock" problem. We use a vector of spin + locks and pick which one to use based on the address of the operand + of the function. + + To generate the index of the lock we first shift by 3 bits to get + rid on the zero bits that result from 32 and 64 bit allignment of + data. We then mask off all but 5 bits and use those 5 bits as an + index into the table. + + Picking the lock this way insures that accesses to the same data at + the same time will go to the same lock. OTOH, accesses to different + data have only a 1/32 chance of hitting the same lock. That should + pretty much eliminate the chances of several atomic operations on + different data from waiting on the same "big lock". If it isn't + then the table of locks can be expanded to a new size so long as + the new size if a power of two. +*/ - return tmp; -#endif -} +static SDL_SpinLock locks[32] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, +}; -Uint16 -SDL_AtomicIncrementThenFetch16(Uint16 * ptr) +static __inline__ void +privateWaitLock(volatile void *ptr) { -#ifdef nativeIncrementThenFetch16 - return nativeIncrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} -Uint16 -SDL_AtomicDecrementThenFetch16(Uint16 * ptr) -{ -#ifdef nativeDecrementThenFetch16 - return nativeDecrementThenFetch16(ptr); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= 1; - tmp = *ptr; - privateUnlock(); - - return tmp; -#endif + SDL_AtomicLock(&locks[index]); } -Uint16 -SDL_AtomicAddThenFetch16(Uint16 * ptr, Uint16 value) +static __inline__ void +privateUnlock(volatile void *ptr) { -#ifdef nativeAddThenFetch16 - return nativeAddThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)+= value; - tmp = *ptr; - privateUnlock(); - - return tmp; +#if SIZEOF_VOIDP == 4 + Uint32 index = ((((Uint32)ptr) >> 3) & 0x1f); +#elif SIZEOF_VOIDP == 8 + Uint64 index = ((((Uint64)ptr) >> 3) & 0x1f); #endif -} - -Uint16 -SDL_AtomicSubtractThenFetch16(Uint16 * ptr, Uint16 value) -{ -#ifdef nativeSubtractThenFetch16 - return nativeSubtractThenFetch16(ptr, value); -#else - Uint16 tmp = 0; - - privateWaitLock(); - (*ptr)-= value; - tmp = *ptr; - privateUnlock(); - return tmp; -#endif + SDL_AtomicUnlock(&locks[index]); } /* 32 bit atomic operations */ -Uint32 -SDL_AtomicExchange32(Uint32 * ptr, Uint32 value) -{ -#ifdef nativeExchange32 - return nativeExchange32(ptr, value); -#else - Uint32 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - SDL_bool -SDL_AtomicCompareThenSet32(Uint32 * ptr, Uint32 oldvalue, Uint32 newvalue) -{ -#ifdef nativeCompareThenSet32 - return (SDL_bool)nativeCompareThenSet32(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - -SDL_bool -SDL_AtomicTestThenSet32(Uint32 * ptr) +SDL_AtomicTestThenSet32(volatile Uint32 * ptr) { #ifdef nativeTestThenSet32 - return (SDL_bool)nativeTestThenSet32(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif } void -SDL_AtomicClear32(Uint32 * ptr) +SDL_AtomicClear32(volatile Uint32 * ptr) { #ifdef nativeClear32 - nativeClear32(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif } Uint32 -SDL_AtomicFetchThenIncrement32(Uint32 * ptr) +SDL_AtomicFetchThenIncrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenIncrement32 - return nativeFetchThenIncrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicFetchThenDecrement32(Uint32 * ptr) +SDL_AtomicFetchThenDecrement32(volatile Uint32 * ptr) { #ifdef nativeFetchThenDecrement32 - return nativeFetchThenDecrement32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicFetchThenAdd32(Uint32 * ptr, Uint32 value) +SDL_AtomicFetchThenAdd32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenAdd32 - return nativeFetchThenAdd32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicFetchThenSubtract32(Uint32 * ptr, Uint32 value) +SDL_AtomicFetchThenSubtract32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeFetchThenSubtract32 - return nativeFetchThenSubtract32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicIncrementThenFetch32(Uint32 * ptr) +SDL_AtomicIncrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeIncrementThenFetch32 - return nativeIncrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicDecrementThenFetch32(Uint32 * ptr) +SDL_AtomicDecrementThenFetch32(volatile Uint32 * ptr) { #ifdef nativeDecrementThenFetch32 - return nativeDecrementThenFetch32(ptr); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicAddThenFetch32(Uint32 * ptr, Uint32 value) +SDL_AtomicAddThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeAddThenFetch32 - return nativeAddThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint32 -SDL_AtomicSubtractThenFetch32(Uint32 * ptr, Uint32 value) +SDL_AtomicSubtractThenFetch32(volatile Uint32 * ptr, Uint32 value) { #ifdef nativeSubtractThenFetch32 - return nativeSubtractThenFetch32(ptr, value); #else Uint32 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif @@ -792,208 +306,161 @@ SDL_AtomicSubtractThenFetch32(Uint32 * ptr, Uint32 value) /* 64 bit atomic operations */ #ifdef SDL_HAS_64BIT_TYPE -Uint64 -SDL_AtomicExchange64(Uint64 * ptr, Uint64 value) -{ -#ifdef nativeExchange64 - return nativeExchange64(ptr, value); -#else - Uint64 tmp = 0; - - privateWaitLock(); - tmp = *ptr; - *ptr = value; - privateUnlock(); - - return tmp; -#endif -} - -SDL_bool -SDL_AtomicCompareThenSet64(Uint64 * ptr, Uint64 oldvalue, Uint64 newvalue) -{ -#ifdef nativeCompareThenSet64 - return (SDL_bool)nativeCompareThenSet64(ptr, oldvalue, newvalue); -#else - SDL_bool result = SDL_FALSE; - - privateWaitLock(); - result = (*ptr == oldvalue); - if (result) - { - *ptr = newvalue; - } - privateUnlock(); - - return result; -#endif -} - SDL_bool -SDL_AtomicTestThenSet64(Uint64 * ptr) +SDL_AtomicTestThenSet64(volatile Uint64 * ptr) { #ifdef nativeTestThenSet64 - return (SDL_bool)nativeTestThenSet64(ptr); #else SDL_bool result = SDL_FALSE; - privateWaitLock(); + privateWaitLock(ptr); result = (*ptr == 0); if (result) { *ptr = 1; } - privateUnlock(); + privateUnlock(ptr); return result; #endif } void -SDL_AtomicClear64(Uint64 * ptr) +SDL_AtomicClear64(volatile Uint64 * ptr) { #ifdef nativeClear64 - nativeClear64(ptr); #else - privateWaitLock(); + privateWaitLock(ptr); *ptr = 0; - privateUnlock(); + privateUnlock(ptr); return; #endif } Uint64 -SDL_AtomicFetchThenIncrement64(Uint64 * ptr) +SDL_AtomicFetchThenIncrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenIncrement64 - return nativeFetchThenIncrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicFetchThenDecrement64(Uint64 * ptr) +SDL_AtomicFetchThenDecrement64(volatile Uint64 * ptr) { #ifdef nativeFetchThenDecrement64 - return nativeFetchThenDecrement64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr) -= 1; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicFetchThenAdd64(Uint64 * ptr, Uint64 value) +SDL_AtomicFetchThenAdd64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenAdd64 - return nativeFetchThenAdd64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)+= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicFetchThenSubtract64(Uint64 * ptr, Uint64 value) +SDL_AtomicFetchThenSubtract64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeFetchThenSubtract64 - return nativeFetchThenSubtract64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); tmp = *ptr; (*ptr)-= value; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicIncrementThenFetch64(Uint64 * ptr) +SDL_AtomicIncrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeIncrementThenFetch64 - return nativeIncrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicDecrementThenFetch64(Uint64 * ptr) +SDL_AtomicDecrementThenFetch64(volatile Uint64 * ptr) { #ifdef nativeDecrementThenFetch64 - return nativeDecrementThenFetch64(ptr); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= 1; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicAddThenFetch64(Uint64 * ptr, Uint64 value) +SDL_AtomicAddThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeAddThenFetch64 - return nativeAddThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)+= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif } Uint64 -SDL_AtomicSubtractThenFetch64(Uint64 * ptr, Uint64 value) +SDL_AtomicSubtractThenFetch64(volatile Uint64 * ptr, Uint64 value) { #ifdef nativeSubtractThenFetch64 - return nativeSubtractThenFetch64(ptr, value); #else Uint64 tmp = 0; - privateWaitLock(); + privateWaitLock(ptr); (*ptr)-= value; tmp = *ptr; - privateUnlock(); + privateUnlock(ptr); return tmp; #endif diff --git a/test/testatomic.c b/test/testatomic.c index cc6429af9..dc97b7e3c 100644 --- a/test/testatomic.c +++ b/test/testatomic.c @@ -29,21 +29,18 @@ main(int argc, char **argv) volatile Uint64 val64 = 0; Uint64 ret64 = 0; + SDL_SpinLock lock = 0; + SDL_bool tfret = SDL_FALSE; - printf("32 bit -----------------------------------------\n\n"); + printf("\nspin lock---------------------------------------\n\n"); - ret32 = SDL_AtomicExchange32(&val32, 10); - printf("Exchange32 ret=%d val=%d\n", ret32, val32); - ret32 = SDL_AtomicExchange32(&val32, 0); - printf("Exchange32 ret=%d val=%d\n", ret32, val32); + SDL_AtomicLock(&lock); + printf("AtomicLock lock=%d\n", lock); + SDL_AtomicUnlock(&lock); + printf("AtomicUnlock lock=%d\n", lock); - val32 = 10; - tfret = SDL_AtomicCompareThenSet32(&val32, 10, 20); - printf("CompareThenSet32 tfret=%s val=%d\n", tf(tfret), val32); - val32 = 10; - tfret = SDL_AtomicCompareThenSet32(&val32, 0, 20); - printf("CompareThenSet32 tfret=%s val=%d\n", tf(tfret), val32); + printf("\n32 bit -----------------------------------------\n\n"); val32 = 0; tfret = SDL_AtomicTestThenSet32(&val32); @@ -79,19 +76,7 @@ main(int argc, char **argv) printf("SubtractThenFetch32 ret=%d val=%d\n", ret32, val32); #ifdef SDL_HAS_64BIT_TYPE - printf("64 bit -----------------------------------------\n\n"); - - ret64 = SDL_AtomicExchange64(&val64, 10); - printf("Exchange64 ret=%lld val=%lld\n", ret64, val64); - ret64 = SDL_AtomicExchange64(&val64, 0); - printf("Exchange64 ret=%lld val=%lld\n", ret64, val64); - - val64 = 10; - tfret = SDL_AtomicCompareThenSet64(&val64, 10, 20); - printf("CompareThenSet64 tfret=%s val=%lld\n", tf(tfret), val64); - val64 = 10; - tfret = SDL_AtomicCompareThenSet64(&val64, 0, 20); - printf("CompareThenSet64 tfret=%s val=%lld\n", tf(tfret), val64); + printf("\n64 bit -----------------------------------------\n\n"); val64 = 0; tfret = SDL_AtomicTestThenSet64(&val64);