Log an ETW event from your Create and Close callbacks.
Author a .wprp which listens for these events and grabs stacks at the time they
happen (see
https://blogs.msdn.microsoft.com/matthew_van_eerde/2018/11/12/what-api-is-being-used-to-play-or-record-audio/)
Record the 2000 calls into an .etl.
Share the .etl.
This will reveal who is instantiating the filters (and, hopefully, why.)
________________________________
From: wdmaudiodev-bounce@xxxxxxxxxxxxx <wdmaudiodev-bounce@xxxxxxxxxxxxx> on
behalf of Gatos, Cobey <cgatos@xxxxxxxxxxxxxxxxx>
Sent: Wednesday, May 15, 2019 10:29:38 AM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Excessive AVStream Driver Filter Creation
I have an AVStream driver for a 10 x 8 USB audio device. The driver exposes
both multi-channel input and output audio devices to Windows, and additionally
stereo pair audio devices for each available audio channel pair. There is a
separate filter factory for each of these (11 total).
When I plug my device in, the driver receives hundreds of filter Create and
Close calls - on one of my machines the number approaches 2000 create calls.
This happens without any audio applications open, and without any pins being
created. These calls can continue for a period of 5 - 10 minutes before they
diminish in frequency and stop. When the calls stop, there will be 50 - 60
filters remaining open, and they remain open until I disconnect the device, at
which point they will all be closed. If the driver exposes only multi-channel
input and output devices (2 filter factories), the number of filter Create
calls will decrease to 60 - 80.
I am curious as to why this is happening. Is this normal behavior for Windows?
I have examined the filter using KS Studio, and compared it to filters created
by Windows USB audio class driver, and I am not noticing any significant issues
or differences.
Thanks.
Cobey******************
WDMAUDIODEV addresses:
Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx
Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe
Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe
Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx
URL to WDMAUDIODEV page:
https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.wdmaudiodev.com%2F&data=01%7C01%7Cmatthew.van.eerde%40microsoft.com%7Ccb8b9c4726114e89a65a08d6d95aff76%7C72f988bf86f141af91ab2d7cd011db47%7C1&sdata=XdiNC4umPLq%2BCIQqCbEuVRrltNfQ1YPI%2FHvTUXnT3zk%3D&reserved=0
