WdfRequestSend on Vista

NTDEV
1

Hi All,

I want to know whether the completion routine of WdfRequestSend(req, target,
WDF_NO_SEND_OPTIONS) gets called in serialized way on Vista. In other words
is there any chance that WDF calls the completion routine of second call
to WdfRequestSend prior to first.

–
Thanks
Amit

2

amit poona wrote:

I want to know whether the completion routine of WdfRequestSend(req,
target, WDF_NO_SEND_OPTIONS) gets called in serialized way on Vista.
In other words is there any chance that WDF calls the completion
routine of second call to WdfRequestSend prior to first.

It depends entirely on the driver you are calling. For example, if you
send a big USB bulk request followed by a short control message, the
control message will complete while the bulk request waits for its data.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.

3

The WDFREQUEST completion routine is not serialized with anything on
Vista (or any OS or version of KMDF). So, yes, the completion routines
can be invoked in any order (depending on who you are sending the io
to). I would assume you are using 2 different WDFREQUESTs here, right?

d

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of amit poona
Sent: Thursday, August 23, 2007 1:39 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] WdfRequestSend on Vista

Hi All,

I want to know whether the completion routine of WdfRequestSend(req,
target, WDF_NO_SEND_OPTIONS) gets called in serialized way on Vista. In
other words is there any chance that WDF calls the completion routine of
second call to WdfRequestSend prior to first.

–
Thanks
Amit

— NTDEV is sponsored by OSR For our schedule of WDF, WDM, debugging
and other seminars visit: http://www.osr.com/seminars To unsubscribe,
visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

4

Yes I am using 2 different WDFREQUEST both to Lower driver which in-turn
sends it out on a single USB bulk out endpoint. And what I observe (through
dbgprints) is that my second requests completion handler gets called priort
to the first.

Thanks
Gautam

On 8/23/07, Doron Holan wrote:
>
> The WDFREQUEST completion routine is not serialized with anything on
> Vista (or any OS or version of KMDF). So, yes, the completion routines can
> be invoked in any order (depending on who you are sending the io to). I
> would assume you are using 2 different WDFREQUESTs here, right?
>
>
>
> d
>
>
>
> From: xxxxx@lists.osr.com [mailto:
> xxxxx@lists.osr.com] *On Behalf Of *amit poona
> Sent: Thursday, August 23, 2007 1:39 PM
> To: Windows System Software Devs Interest List
> Subject: [ntdev] WdfRequestSend on Vista
>
>
>
> Hi All,
>
>
>
> I want to know whether the completion routine of WdfRequestSend(req,
> target, WDF_NO_SEND_OPTIONS) gets called in serialized way on Vista. In
> other words is there any chance that WDF calls the completion routine
> of second call to WdfRequestSend prior to first.
>
>
> –
> Thanks
> Amit
>
> — NTDEV is sponsored by OSR For our schedule of WDF, WDM, debugging and
> other seminars visit: http://www.osr.com/seminars To unsubscribe, visit
> the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer
>
> —
> NTDEV is sponsored by OSR
>
> For our schedule of WDF, WDM, debugging and other seminars visit:
> http://www.osr.com/seminars
>
> To unsubscribe, visit the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer
>

–
Thanks
Amit

5

amit poona wrote:

Yes I am using 2 different WDFREQUEST both to Lower driver which
in-turn sends it out on a single USB bulk out endpoint. And what I
observe (through dbgprints) is that my second requests completion
handler gets called priort to the first.

Requests for a single pipe will always come back in the order they were
sent. There must be something else going on here.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.