OSAtomicOperations.c [plain text]
#include <libkern/OSAtomic.h>
#include <kern/debug.h>
#include <machine/atomic.h>
enum {
false = 0,
true = 1
};
#ifndef NULL
#define NULL ((void *)0)
#endif
#define ATOMIC_DEBUG DEBUG
#if ATOMIC_DEBUG
#define ALIGN_TEST(p, t) do{if((uintptr_t)p&(sizeof(t)-1)) panic("Unaligned atomic pointer %p\n",p);}while(0)
#else
#define ALIGN_TEST(p, t) do{}while(0)
#endif
#undef OSCompareAndSwap8
Boolean
OSCompareAndSwap8(UInt8 oldValue, UInt8 newValue, volatile UInt8 *address)
{
return os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
#undef OSCompareAndSwap16
Boolean
OSCompareAndSwap16(UInt16 oldValue, UInt16 newValue, volatile UInt16 *address)
{
return os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
#undef OSCompareAndSwap
Boolean
OSCompareAndSwap(UInt32 oldValue, UInt32 newValue, volatile UInt32 *address)
{
ALIGN_TEST(address, UInt32);
return os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
#undef OSCompareAndSwap64
Boolean
OSCompareAndSwap64(UInt64 oldValue, UInt64 newValue, volatile UInt64 *address)
{
_Atomic UInt64 *aligned_addr = (_Atomic UInt64 *)(uintptr_t)address;
ALIGN_TEST(address, UInt64);
return os_atomic_cmpxchg(aligned_addr, oldValue, newValue, acq_rel);
}
#undef OSCompareAndSwapPtr
Boolean
OSCompareAndSwapPtr(void *oldValue, void *newValue, void * volatile *address)
{
return os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
SInt8
OSAddAtomic8(SInt32 amount, volatile SInt8 *address)
{
return os_atomic_add_orig(address, amount, relaxed);
}
SInt16
OSAddAtomic16(SInt32 amount, volatile SInt16 *address)
{
return os_atomic_add_orig(address, amount, relaxed);
}
#undef OSAddAtomic
SInt32
OSAddAtomic(SInt32 amount, volatile SInt32 *address)
{
ALIGN_TEST(address, UInt32);
return os_atomic_add_orig(address, amount, relaxed);
}
#undef OSAddAtomic64
SInt64
OSAddAtomic64(SInt64 amount, volatile SInt64 *address)
{
_Atomic SInt64* aligned_address = (_Atomic SInt64*)(uintptr_t)address;
ALIGN_TEST(address, SInt64);
return os_atomic_add_orig(aligned_address, amount, relaxed);
}
#undef OSAddAtomicLong
long
OSAddAtomicLong(long theAmount, volatile long *address)
{
return os_atomic_add_orig(address, theAmount, relaxed);
}
#undef OSIncrementAtomic
SInt32
OSIncrementAtomic(volatile SInt32 * value)
{
return os_atomic_inc_orig(value, relaxed);
}
#undef OSDecrementAtomic
SInt32
OSDecrementAtomic(volatile SInt32 * value)
{
return os_atomic_dec_orig(value, relaxed);
}
#undef OSBitAndAtomic
UInt32
OSBitAndAtomic(UInt32 mask, volatile UInt32 * value)
{
return os_atomic_and_orig(value, mask, relaxed);
}
#undef OSBitOrAtomic
UInt32
OSBitOrAtomic(UInt32 mask, volatile UInt32 * value)
{
return os_atomic_or_orig(value, mask, relaxed);
}
#undef OSBitXorAtomic
UInt32
OSBitXorAtomic(UInt32 mask, volatile UInt32 * value)
{
return os_atomic_xor_orig(value, mask, relaxed);
}
static Boolean
OSTestAndSetClear(UInt32 bit, Boolean wantSet, volatile UInt8 * startAddress)
{
UInt8 mask = 1;
UInt8 oldValue, newValue;
UInt8 wantValue;
UInt8 *address;
address = (UInt8 *)(uintptr_t)(startAddress + (bit / 8));
mask <<= (7 - (bit % 8));
wantValue = wantSet ? mask : 0;
return !os_atomic_rmw_loop(address, oldValue, newValue, relaxed, {
if ((oldValue & mask) == wantValue) {
os_atomic_rmw_loop_give_up(break);
}
newValue = (oldValue & ~mask) | wantValue;
});
}
Boolean
OSTestAndSet(UInt32 bit, volatile UInt8 * startAddress)
{
return OSTestAndSetClear(bit, true, startAddress);
}
Boolean
OSTestAndClear(UInt32 bit, volatile UInt8 * startAddress)
{
return OSTestAndSetClear(bit, false, startAddress);
}
SInt8
OSIncrementAtomic8(volatile SInt8 * value)
{
return os_atomic_inc_orig(value, relaxed);
}
SInt8
OSDecrementAtomic8(volatile SInt8 * value)
{
return os_atomic_dec_orig(value, relaxed);
}
UInt8
OSBitAndAtomic8(UInt32 mask, volatile UInt8 * value)
{
return os_atomic_and_orig(value, mask, relaxed);
}
UInt8
OSBitOrAtomic8(UInt32 mask, volatile UInt8 * value)
{
return os_atomic_or_orig(value, mask, relaxed);
}
UInt8
OSBitXorAtomic8(UInt32 mask, volatile UInt8 * value)
{
return os_atomic_xor_orig(value, mask, relaxed);
}
SInt16
OSIncrementAtomic16(volatile SInt16 * value)
{
return OSAddAtomic16(1, value);
}
SInt16
OSDecrementAtomic16(volatile SInt16 * value)
{
return OSAddAtomic16(-1, value);
}
UInt16
OSBitAndAtomic16(UInt32 mask, volatile UInt16 * value)
{
return os_atomic_and_orig(value, mask, relaxed);
}
UInt16
OSBitOrAtomic16(UInt32 mask, volatile UInt16 * value)
{
return os_atomic_or_orig(value, mask, relaxed);
}
UInt16
OSBitXorAtomic16(UInt32 mask, volatile UInt16 * value)
{
return os_atomic_xor_orig(value, mask, relaxed);
}