DRM IOCTLS come regularly(every minute) still even after screen off

[Michel Dänzer]

On 2021-09-16 08:27, Christian König wrote:
> Good morning,
> 
> for the background I advised to contact you Michel since we couldn't find an explanation.
> 
> Alex explanation might be correct, but the CS seems to come from the X server and is always roughly 60 seconds after going into power save.
> 
> Any idea what that could be?

For the DRM_IOCTL_MODE_* ioctls, attaching gdb to Xorg and setting a breakpoint on drmIoctl should show where they're coming from.

The AMDGPU_CS ioctls are probably from glamor calling OpenGL, most likely for X11 drawing protocol requests. Note that in this case drmIoctl/ioctl will likely be called from a separate thread. Pierre / Marek should be able to help you find out where the OpenGL calls are coming from.


In general, Xorg only ever does anything in response to:

* X11 protocol requests, i.e. on behalf of clients.
* Input events, i.e. on behalf of the user.
* Other kernel events, e.g. hotplug events.


FWIW, with only xfwm4 & xterm running on Xorg, I'm not seeing any drmIoctl calls during DPMS off. So the ioctls you're seeing are most likely triggered by clients.


-- 
Earthling Michel Dänzer               |               https://redhat.com
Libre software enthusiast             |             Mesa and X developer