#include <cafe/os.h> BOOL OSUninterruptibleSpinLock_Acquire(OSSpinLock* inSpinlock);
|inSpinlock||Pointer to uninterruptible spinlock.|
BOOL indicating success or failure.
OSUninterruptibleSpinLock_Acquire busy-waits to acquire an
OSUninterruptibleSpinLock if the spinlock has never been acquired. A thread may acquire an
OSUninterruptibleSpinLock recursively. Upon acquiring an
OSUninterruptibleSpinLock, interrupts are disabled. A thread must not leave interrupts disabled for long periods of time,
typically no longer than 1-2 microseconds to avoid disrupting user-mode COS components.
OSUninterruptibleSpinLock is approximately 5X faster to acquire and release than a regular
OSSpinLock and creates no contention for internal COS locks. The major condition is that between acquiring and releasing the
OSUninterruptibleSpinLock, interrupts are disabled and must remain disabled until the corresponding
OSUninterruptibleSpinLock_Release is called.
OSUninterruptibleSpinLock_Release purposely have the same parameter lists and same-sized data structures as the
OSSpinLock Acquire and Release functions. This is so that
OSUninterruptibleSpinLock can serve as a drop-in replacement for regular
OSSpinLock in many situations.
OSUninterruptibleSpinLocks do not participate in the thread canceling mechanism. If a thread wishes to benefit from both the faster
OSUninterruptibleSpinLock and from the ability to cross-thread cancel a thread,
OSTestThreadCancel should be called before
OSUninterruptibleSpinLock_Acquire and after
Important usage notes while holding a spinlock:
OSUninterruptibleSpinlock is designed to handle thread priority inversion issues. However,
OSUninterruptibleSpinlock still busy-waits. If a thread wants to sleep one needs to use an
2013/05/08 Automated cleanup pass.
2012/08/01 Cleanup Pass.
2012/04/21 Initial version.