HwVidSynchronizeExecutionCallback

BOOLEAN HwVidSynchronizeExecutionCallback(

IN PVOID Context

);

HwVidSynchronizeExecutionCallback is an optional miniport driver function, passed in calls to VideoPortSynchronizeExecution.

Parameters

Context: Points to context data passed to the callback routine through VideoPortSynchronizeExecution. Usually, this is a pointer to the device extension or an offset within the device extension.

Return Value

If the operation succeeds, HwVidSynchronizeExecutionCallback returns TRUE.

Comments

A miniport driver with one or more functions that share memory with its HwVidInterrupt function must have a HwVidSynchronizeExecutionCallback function. Any function that shares memory with HwVidInterrupt must call VideoPortSynchronizeExecution with the HwVidSynchronizeExecutionCallback to maintain the integrity of data in the shared memory area. That is, only one of the HwVidSynchronizeExecutionCallback and HwInterrupt functions can update state in the shared area at any given moment.

The miniport driver of an adapter that does not generate interrupts also can have a HwVidSynchronizeExecutionCallback function to be passed to VideoPortSynchronizeExecution when such a driver needs to get some critical work done at a relatively high runtime priority. For example, VGA-compatible miniport drivers with SvgaHwIoPortXxx functions might have a HwVidSynchronizeExecutionCallback that is responsible for transferring driver-buffered and validated application-issued I/O to the adapter.