How to produce the race condition by DDK.3790?

There are so much dualcore/hyperthreading platforms.
Does the DDK can build out the real multi-treading supported driver?
I maintain the vga driver. In WinXP, the vga driver own 2 parts, miniport
and display. I made 2 tests, the 1st can overlap display/miniport function;
the other can't. I don't know why the 2nd test can't produce the race
condition.

case 1) This can make it.
T1: The pc-cam call directdraw function repeatly.
T2: The miniport interrupt function check this interrupt belong to
repeatly?

case 2) I confused this.
T1: One AP fired IRP to the IRP handle of miniport function. It's fireing
repeatly.
T2: The dvd player use directdraw function play the video file.

Why the case 2 can't produce the race condition?? Does the ddk3790 support
multi-threading? Or I got the mistake. The display and miniport part never
overlap, they are sequential except the isolation level is high.

-william

WilliamW
Wed Apr 12 07:12:01 CDT 2006

I tried
Pentium4 single core with hyperthreading;
PentiumD 820 dual core with no-hyperthreading;
PentiumD 920 dual core with no-hyperthreading;
Can I say the architecture of xp vga driver is sequential running mode
except the interrupt handle function? In my test2, even
display/directdraw/video part is very very busy. But the utility --> IRP
-->display's DriverEscape(...) never overlapped display directdraw function.
Is it the correct rule?


"William W" ���

> There are so much dualcore/hyperthreading platforms.
> Does the DDK can build out the real multi-treading supported driver?
> I maintain the vga driver. In WinXP, the vga driver own 2 parts, miniport
> and display. I made 2 tests, the 1st can overlap display/miniport function;
> the other can't. I don't know why the 2nd test can't produce the race
> condition.
>
> case 1) This can make it.
> T1: The pc-cam call directdraw function repeatly.
> T2: The miniport interrupt function check this interrupt belong to
> repeatly?
>
> case 2) I confused this.
> T1: One AP fired IRP to the IRP handle of miniport function. It's fireing
> repeatly.
> T2: The dvd player use directdraw function play the video file.
>
> Why the case 2 can't produce the race condition?? Does the ddk3790 support
> multi-threading? Or I got the mistake. The display and miniport part never
> overlap, they are sequential except the isolation level is high.
>
> -william
>