OSDecAtomic64

Syntax

#include <cafe/os.h>

#define OSDecAtomic64(ptr) OSAddAtomic64(ptr, -1)

Parameters

ptr Pointer to data to decrement atomically.

Return Values

s64 with the previous value.

Description

OSDecAtomic64 performs an atomic decrement by 1 with a 64-bit value in memory. This is useful if the value needs to be atomically manipulated by multiple processors.

It does not act as a memory barrier.

CAUTION:
This 64-bit API implementation is much slower than its equivalent 32-bit atomic API version. If 64-bit values are not needed, use the 32-bit atomic API version instead. The 32-bit version is listed in the See Also section of this topic. For more information, see Synchronization and Atomics in the Espresso CPU Performance Guide.

Do Not Call From

None.

See Also

OSAddAtomic64
OSAndAtomic64
OSCompareAndSwapAtomic64
OSCompareAndSwapAtomicEx64
OSDecAtomic (32-bit)
OSGetAtomic64
OSIncAtomic64
OSOrAtomic64
OSSetAtomic64
OSSwapAtomic64
OSTestAndClearAtomic64
OSTestAndSetAtomic64
OSXorAtomic64

Revision History

2014/07/08 Added 64-bit caution.
2013/05/08 Automated cleanup pass.
2012/07/30 Cleanup Pass.
2010/08/30 Initial version.


CONFIDENTIAL