[RFC PATCH 0/6] drm/sched: Avoid memory leaks by canceling job-by-job

[Tvrtko Ursulin]

On 03/06/2025 10:31, Philipp Stanner wrote:
> An alternative version to [1], based on Tvrtko's suggestion from [2].
> 
> I tested this for Nouveau. Works.
> 
> I'm having, however, bigger problems properly porting the unit tests and
> have seen various explosions. In the process I noticed that some things
> in the unit tests aren't right and a bit of a larger rework will be
> necessary (for example, the timedout job callback must signal the
> timedout fence, remove it from the list and so on).

General approach I follow when implementing any mock component is to 
implement only as much is needed for a test to pass. Only add more and 
rework when a test/functionality is added which requires it.

Specifically for timedout callback signaling I see that I had exactly 
that added in the patch you linked as [2].
  > Anyways. Please comment on the general idea.

I am obviously okay with it. :) Especially now that you verified it 
works well for nouveau.

What I am not that ecstatic about is only getting the Suggested-by 
credit in 1/6. Given it is basically my patch with some cosmetic changes 
like the kernel doc and the cancel loop extracted to a helper.

> @Tvrtko: As briefly brainstormed about on IRC, if you'd be willing to
> take care of the unit tests patch, I could remove that one (and,
> maaaaybe, the warning print patch) from the series and we could merge
> this RFC's successor version %N once it's ready. What do you think?

Okay in principle but the first thing I would suggest you could try is 
to take my unit tests adaptations from [2] verbatim. Benefit of keeping 
everything in one series is more confidence we are merging a solid 
thing. But I can take it on myself as a follow up too if you want.

Regards,

Tvrtko

> 
> P.
> 
> [1] https://lore.kernel.org/dri-devel/20250522082742.148191-2-phasta@kernel.org/
> [2] https://lore.kernel.org/dri-devel/20250418113211.69956-1-tvrtko.ursulin@igalia.com/
> 
> Philipp Stanner (6):
>    drm/sched: Avoid memory leaks with cancel_job() callback
>    drm/sched/tests: Implement cancel_job()
>    drm/sched: Warn if pending list is not empty
>    drm/nouveau: Make fence container helper usable driver-wide
>    drm/nouveau: Add new callback for scheduler teardown
>    drm/nouveau: Remove waitque for sched teardown
> 
>   drivers/gpu/drm/nouveau/nouveau_fence.c       | 35 +++++----
>   drivers/gpu/drm/nouveau/nouveau_fence.h       |  7 ++
>   drivers/gpu/drm/nouveau/nouveau_sched.c       | 35 +++++----
>   drivers/gpu/drm/nouveau/nouveau_sched.h       |  9 +--
>   drivers/gpu/drm/nouveau/nouveau_uvmm.c        |  8 +--
>   drivers/gpu/drm/scheduler/sched_main.c        | 37 ++++++----
>   .../gpu/drm/scheduler/tests/mock_scheduler.c  | 71 +++++++------------
>   drivers/gpu/drm/scheduler/tests/sched_tests.h |  4 +-
>   include/drm/gpu_scheduler.h                   |  9 +++
>   9 files changed, 115 insertions(+), 100 deletions(-)
>