Re: WinXPSP2, Intel Core2Duo, Kernel drivers

Hi Calvin

once the driver works fine on SMP machine, it
automatically implies it will work fine on UP one as well.

Believe it or not, this is not true.

My statement is based upon the "bold" assumption that the driver in
question relies only upon the "supported" stuff. Certainly, if it, say,
uses SYNCH_LEVEL directly (i.e. does something that drivers are not
supposed to do), then it may work fine on MP kernel and fail on UP one
- on UP kernel SYNCH_LEVEL equals DISPATCH_LEVEL, although on MP one it
equals CLOCK2_LEVEL. Similarly, if it uses KeQueryPerformanceCounter()
in order to measure the elapsed time(again, something drivers are not
supposed to do), implications may be quite different for UP and MP
kernels. However, as long as it plays by the rules, my statement
holds....



Anton Bassov

Calvin Guan wrote:
<soviet_bloke@xxxxxxxxxxx> wrote in message
news:1157600038.483526.248840@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
In fact, it just does not make sense to write "non-SMP aware" drivers,
in the first place

well said.

once the driver works fine on SMP machine, it
automatically implies it will work fine on UP one as well.

Believe it or not, this is not true.

--
Calvin Guan (DDK MVP)
Sr. Staff Engineer
NetXtreme Vista/Longhorn Server Miniport
Broadcom Corporation
Connecting Everything(r)

.

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