VideoPortAcquireSpinLockAtDpcLevel - NtDoc
Native API online documentation, based on the System Informer
(formerly Process Hacker) phnt
headers
// video.h
VIDEOPORT_API VOID VideoPortAcquireSpinLockAtDpcLevel(
[in, out] PVOID HwDeviceExtension,
[in] PSPIN_LOCK SpinLock
);
View the official Windows Driver Kit DDI referenceNo description available.
The VideoPortAcquireSpinLockAtDpcLevel function acquires a spin lock when the caller is already running at IRQL = DISPATCH_LEVEL.
HwDeviceExtension [in, out]Pointer to the miniport driver's device extension.
SpinLock [in]Pointer to a memory location that contains the spin lock.
None
Miniport drivers call VideoPortAcquireSpinLockAtDpcLevel instead of VideoPortAcquireSpinLock for better driver performance if and only if they are already running at IRQL = DISPATCH_LEVEL.
If a miniport driver is running at IRQL < DISPATCH_LEVEL, it should call VideoPortAcquireSpinLock to have IRQL raised by that routine. VideoPortAcquireSpinLockAtDpcLevel requires the caller to be running already at IRQL = DISPATCH_LEVEL, so no raise is necessary.
The caller should release the spin lock with VideoPortReleaseSpinLockFromDpcLevel as quickly as possible.
VideoPortReleaseSpinLockFromDpcLevel