[PATCH 8/9] drm/amdgpu/userq: add helpers to start/stop scheduling

[Alex Deucher]

On Fri, Apr 11, 2025 at 12:17 PM Khatri, Sunil <sukhatri at amd.com> wrote:
>
>
> On 4/11/2025 7:42 PM, Alex Deucher wrote:
> > This will be used to stop/start user queue scheduling for
> > example when switching between kernel and user queues when
> > enforce isolation is enabled.
> >
> > Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu.h           |  1 +
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 68 ++++++++++++++++---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.h |  3 +
> >   3 files changed, 64 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > index b156e31ac86ac..30c485f529d17 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > @@ -1249,6 +1249,7 @@ struct amdgpu_device {
> >
> >       struct list_head                userq_mgr_list;
> >       struct mutex                    userq_mutex;
> > +     bool                            userq_halt;
> >   };
> >
> >   static inline uint32_t amdgpu_ip_version(const struct amdgpu_device *adev,
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> > index aa7222137c31d..e93e390f4e301 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> > @@ -335,6 +335,7 @@ amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq *args)
> >               goto unlock;
> >       }
> >
> > +
> >       qid = idr_alloc(&uq_mgr->userq_idr, queue, 1, AMDGPU_MAX_USERQ_COUNT, GFP_KERNEL);
> >       if (qid < 0) {
> >               DRM_ERROR("Failed to allocate a queue id\n");
> > @@ -345,15 +346,21 @@ amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq *args)
> >               goto unlock;
> >       }
> >
> > -     r = uq_funcs->map(uq_mgr, queue);
> > -     if (r) {
> > -             DRM_ERROR("Failed to map Queue\n");
> > -             idr_remove(&uq_mgr->userq_idr, qid);
> > -             amdgpu_userq_fence_driver_free(queue);
> > -             uq_funcs->mqd_destroy(uq_mgr, queue);
> > -             kfree(queue);
> > -             goto unlock;
> > +     /* don't map the queue if scheduling is halted */
> > +     mutex_lock(&adev->userq_mutex);
> > +     if (!adev->userq_halt) {
> > +             r = uq_funcs->map(uq_mgr, queue);
> > +             if (r) {
> > +                     DRM_ERROR("Failed to map Queue\n");
> > +                     mutex_unlock(&adev->userq_mutex);
> > +                     idr_remove(&uq_mgr->userq_idr, qid);
> > +                     amdgpu_userq_fence_driver_free(queue);
> > +                     uq_funcs->mqd_destroy(uq_mgr, queue);
> > +                     kfree(queue);
> > +                     goto unlock;
> > +             }
> >       }
> > +     mutex_unlock(&adev->userq_mutex);
> >
> >       args->out.queue_id = qid;
> >
> > @@ -720,3 +727,48 @@ int amdgpu_userq_resume(struct amdgpu_device *adev)
> >       mutex_unlock(&adev->userq_mutex);
> >       return ret;
> >   }
> > +
> > +int amdgpu_userq_stop_sched(struct amdgpu_device *adev, u32 idx)
> Did i miss something of the param "idx" isnt being used in this function
> ? Same is applicable for start shed .

It's only applicable for chips with multiple XCDs,  gfx11 and 12 are
only single XCDs so it's unused for now.

Alex

> Regards
> Sunil
> > +{
> > +     const struct amdgpu_userq_funcs *userq_funcs;
> > +     struct amdgpu_usermode_queue *queue;
> > +     struct amdgpu_userq_mgr *uqm, *tmp;
> > +     int queue_id;
> > +     int ret = 0;
> > +
> > +     mutex_lock(&adev->userq_mutex);
> > +     if (adev->userq_halt)
> > +             dev_warn(adev->dev, "userq scheduling already stopped!\n");
> > +     adev->userq_halt = true;
> > +     list_for_each_entry_safe(uqm, tmp, &adev->userq_mgr_list, list) {
> > +             cancel_delayed_work_sync(&uqm->resume_work);
> > +             idr_for_each_entry(&uqm->userq_idr, queue, queue_id) {
> > +                     userq_funcs = adev->userq_funcs[queue->queue_type];
> > +                     ret |= userq_funcs->unmap(uqm, queue);
> > +             }
> > +     }
> > +     mutex_unlock(&adev->userq_mutex);
> > +     return ret;
> > +}
> > +
> > +int amdgpu_userq_start_sched(struct amdgpu_device *adev, u32 idx)
> > +{
> > +     const struct amdgpu_userq_funcs *userq_funcs;
> > +     struct amdgpu_usermode_queue *queue;
> > +     struct amdgpu_userq_mgr *uqm, *tmp;
> > +     int queue_id;
> > +     int ret = 0;
> > +
> > +     mutex_lock(&adev->userq_mutex);
> > +     if (!adev->userq_halt)
> > +             dev_warn(adev->dev, "userq scheduling already started!\n");
> > +     adev->userq_halt = false;
> > +     list_for_each_entry_safe(uqm, tmp, &adev->userq_mgr_list, list) {
> > +             idr_for_each_entry(&uqm->userq_idr, queue, queue_id) {
> > +                     userq_funcs = adev->userq_funcs[queue->queue_type];
> > +                     ret |= userq_funcs->map(uqm, queue);
> > +             }
> > +     }
> > +     mutex_unlock(&adev->userq_mutex);
> > +     return ret;
> > +}
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.h
> > index 381b9c6f0573d..fd0542f60433b 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.h
> > @@ -114,4 +114,7 @@ uint64_t amdgpu_userqueue_get_doorbell_index(struct amdgpu_userq_mgr *uq_mgr,
> >   int amdgpu_userq_suspend(struct amdgpu_device *adev);
> >   int amdgpu_userq_resume(struct amdgpu_device *adev);
> >
> > +int amdgpu_userq_stop_sched(struct amdgpu_device *adev, u32 idx);
> > +int amdgpu_userq_start_sched(struct amdgpu_device *adev, u32 idx);
> > +
> >   #endif