[PATCH 0/7] Preemption support for A7XX

[Connor Abbott]

On Fri, Aug 23, 2024 at 9:30 AM <neil.armstrong at linaro.org> wrote:
>
> On 15/08/2024 20:26, Antonino Maniscalco wrote:
> > This series implements preemption for A7XX targets, which allows the GPU to
> > switch to an higher priority ring when work is pushed to it, reducing latency
> > for high priority submissions.
> >
> > This series enables L1 preemption with skip_save_restore which requires
> > the following userspace patches to function:
> >
> > https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30544
> >
> > A flag is added to `msm_gem_submit` to only allow submissions from compatible
> > userspace to be preempted, therefore maintaining compatibility.
> >
> > Some commits from this series are based on a previous series to enable
> > preemption on A6XX targets:
> >
> > https://lkml.kernel.org/1520489185-21828-1-git-send-email-smasetty@codeaurora.org
> >
> > Signed-off-by: Antonino Maniscalco <antomani103 at gmail.com>
> > ---
> > Antonino Maniscalco (7):
> >        drm/msm: Fix bv_fence being used as bv_rptr
> >        drm/msm: Add submitqueue setup and close
> >        drm/msm: Add a `preempt_record_size` field
> >        drm/msm/A6xx: Implement preemption for A7XX targets
> >        drm/msm/A6xx: Add traces for preemption
> >        drm/msm/A6XX: Add a flag to allow preemption to submitqueue_create
> >        drm/msm/A6xx: Enable preemption for A7xx targets
> >
> >   drivers/gpu/drm/msm/Makefile              |   1 +
> >   drivers/gpu/drm/msm/adreno/a6xx_catalog.c |   3 +
> >   drivers/gpu/drm/msm/adreno/a6xx_gpu.c     | 339 ++++++++++++++++++++++-
> >   drivers/gpu/drm/msm/adreno/a6xx_gpu.h     | 168 ++++++++++++
> >   drivers/gpu/drm/msm/adreno/a6xx_preempt.c | 441 ++++++++++++++++++++++++++++++
> >   drivers/gpu/drm/msm/adreno/adreno_gpu.h   |   1 +
> >   drivers/gpu/drm/msm/msm_gpu.h             |   7 +
> >   drivers/gpu/drm/msm/msm_gpu_trace.h       |  28 ++
> >   drivers/gpu/drm/msm/msm_ringbuffer.h      |   8 +
> >   drivers/gpu/drm/msm/msm_submitqueue.c     |  10 +
> >   include/uapi/drm/msm_drm.h                |   5 +-
> >   11 files changed, 995 insertions(+), 16 deletions(-)
> > ---
> > base-commit: 7c626ce4bae1ac14f60076d00eafe71af30450ba
> > change-id: 20240815-preemption-a750-t-fcee9a844b39
> >
> > Best regards,
>
> For what is worth, I've tested it on the SM8650 QRD with the Mesa 30544 MR & vkcube
>
> Tested-by: Neil Armstrong <neil.armstrong at linaro.org> # on SM8650-QRD
>
> If you think of more tests to run, please tell me.
>
> Neil

Hi Neil,

I think it would help to test this on SM8550 and SM8450 too. I don't
have SM8450 to test with. Maybe also worth mentioning that there are
now vulkan CTS tests that try to test L1 preemption:
https://github.com/KhronosGroup/VK-GL-CTS/commit/7e0e4a000f34e748bb527b39f730f78b595140b9
although it's not in a released version yet.

Connor