On 4/8/26 07:36, Sunil Khatri wrote:
> Reorganise code to avoid holding mutex userq_mutex while
> also trying to grab exec lock ww_mutex where its not needed
> for function amdgpu_userq_input_va_validate
>
> Signed-off-by: Sunil Khatri <[email protected]>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 33 +++++++++++------------
> 1 file changed, 15 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
> index 3a6e7a569c78..3f502c18879a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
> @@ -737,28 +737,17 @@ amdgpu_userq_create(struct drm_file *filp, union
> drm_amdgpu_userq *args)
> return r;
> }
>
> - /*
> - * There could be a situation that we are creating a new queue while
> - * the other queues under this UQ_mgr are suspended. So if there is any
> - * resume work pending, wait for it to get done.
> - *
> - * This will also make sure we have a valid eviction fence ready to be
> used.
> - */
> - amdgpu_userq_ensure_ev_fence(&fpriv->userq_mgr, &fpriv->evf_mgr);
> -
> uq_funcs = adev->userq_funcs[args->in.ip_type];
> if (!uq_funcs) {
> drm_file_err(uq_mgr->file, "Usermode queue is not supported for
> this IP (%u)\n",
> args->in.ip_type);
> - r = -EINVAL;
> - goto unlock;
> + return -EINVAL;
> }
>
> queue = kzalloc(sizeof(struct amdgpu_usermode_queue), GFP_KERNEL);
> if (!queue) {
> drm_file_err(uq_mgr->file, "Failed to allocate memory for
> queue\n");
> - r = -ENOMEM;
> - goto unlock;
> + return -ENOMEM;
> }
>
> INIT_LIST_HEAD(&queue->userq_va_list);
> @@ -781,12 +770,21 @@ amdgpu_userq_create(struct drm_file *filp, union
> drm_amdgpu_userq *args)
> goto free_queue;
> }
>
> + /*
> + * There could be a situation that we are creating a new queue while
> + * the other queues under this UQ_mgr are suspended. So if there is any
> + * resume work pending, wait for it to get done.
> + *
> + * This will also make sure we have a valid eviction fence ready to be
> used.
> + */
> + amdgpu_userq_ensure_ev_fence(&fpriv->userq_mgr, &fpriv->evf_mgr);
Even that position is not correct. After grabbing the userq_mutex we can't
allocate memory any more.
> +
> /* Convert relative doorbell offset into absolute doorbell index */
> index = amdgpu_userq_get_doorbell_index(uq_mgr, &db_info, filp);
> if (index == (uint64_t)-EINVAL) {
> drm_file_err(uq_mgr->file, "Failed to get doorbell for
> queue\n");
> r = -EINVAL;
> - goto free_queue;
> + goto unlock;
> }
>
> queue->doorbell_index = index;
> @@ -794,7 +792,7 @@ amdgpu_userq_create(struct drm_file *filp, union
> drm_amdgpu_userq *args)
> r = amdgpu_userq_fence_driver_alloc(adev, &queue->fence_drv);
So doing that here is also forbidden.
Regards,
Christian.
> if (r) {
> drm_file_err(uq_mgr->file, "Failed to alloc fence driver\n");
> - goto free_queue;
> + goto unlock;
> }
>
> r = uq_funcs->mqd_create(queue, &args->in);
> @@ -858,11 +856,10 @@ amdgpu_userq_create(struct drm_file *filp, union
> drm_amdgpu_userq *args)
> up_read(&adev->reset_domain->sem);
> clean_fence_driver:
> amdgpu_userq_fence_driver_free(queue);
> -free_queue:
> - kfree(queue);
> unlock:
> mutex_unlock(&uq_mgr->userq_mutex);
> -
> +free_queue:
> + kfree(queue);
> return r;
> }
>
