Re: [RFC PATCH v1 1/2] drm/syncobj: Add DRM_IOCTL_SYNCOBJ_QUERY_ERROR to query fence error status

[Yicong Hui]

On 2/17/26 10:29 AM, Christian König wrote:
> On 2/13/26 13:08, Yicong Hui wrote:
> > Add DRM_IOCTL_SYNCOBJ_QUERY_ERROR to allow userspace to query the error
> > status of a fence held by a timeline/binary syncobj.
>
> Not bad for a first try, but quite a bunch of general comments.
>
> First of all to get that merged you need to point out a Mesa merge request where this interface is actually used in userspace, so that we can look at the full solution.


> My educated guess is that userspace doesn't want to call this IOCTL separately because of performance reasons.
>
> Instead add some additional flag to DRM_SYNCOBJ_WAIT_FLAGS_* so that the IOCTL aborts the wait and returns an error as soon as it sees any fence with an error.
>
> Another DRM_SYNCOBJ_QUERY_FLAGS_* is potentially also useful to query the error on a number of drm_syncobjs at the same time.
>
> But in general since this is not a HW feature the userspace developers need to voice their requirements and explain how they want to have that implemented.
>
> So adding Michel on CC, I've briefly discussed that topic with him on XDC last year.
>
> Thanks,
> Christian.


Hi, thank you for the feedback! :D

Shall I just wait for Michel's input on what interface would work best for Mesa?

Thank you!
-Yicong