Supplying Fence Identifiers

The Microsoft DirectX graphics kernel subsystem supplies an identical fence identifier in the SubmissionFenceId members of the DXGKARG_PATCH andDXGKARG_SUBMITCOMMAND structures
in calls to the display miniport driver's DxgkDdiPatch and DxgkDdiSubmitCommand functions.
Depending on how the graphics hardware is implemented, the driver is only required to use the fence identifier passed to one of either the DxgkDdiPatch or DxgkDdiSubmitCommandfunction for the following reasons:

The driver uses the fence identifier passed to DxgkDdiPatch to write into the end of the direct memory access (DMA) buffer.

The driver uses the fence identifier passed to DxgkDdiSubmitCommand to write into the ring buffer, which is the buffer where DMA buffers are queued for execution by the graphics processing unit (GPU) (most GPU types use a DMA buffer queuing model).

DXGK提供一个fence
id，存在于DXGKARG_PATCH andDXGKARG_SUBMITCOMMAND 结构体成员SubmissionFenceId 。取决于显卡的实现，驱动只需要在以下两种情况下使用fence
id

1.
驱动使用传送到DxgkDdiPatch 的fence
id，写入DMA buffer的结尾。
2.
驱动使用传送到DxgkDdiSubmitCommand 的fence
id，写入环形缓冲区，该缓冲区用于DMA buffer获取GPU处理的结果。