Re: [PATCH v2 06/08] drm/amdgpu: Add few optimizations to userq fence driver

[Christian König <ckoenig.leichtzumerken@xxxxxxxxx>]

Am 25.09.24 um 21:59 schrieb Arunpravin Paneer Selvam:
> Add few optimizations to userq fence driver.

"Few optimization and fixes for userq fence driver".

> v1:(Christian):
>    - Remove unnecessary comments.
>    - In drm_exec_init call give num_bo_handles as last parameter it would
>      making allocation of the array more efficient
>    - Handle return value of __xa_store() and improve the error handling of
>      amdgpu_userq_fence_driver_alloc().
>
> v2:(Christian):
>     - Revert userq_xa xarray init to XA_FLAGS_LOCK_IRQ.
>     - move the xa_unlock before the error check of the call xa_err(__xa_store())
>       and moved this change to a separate patch as this is adding a missing error
>       handling.
>     - Removed the unnecessary comments.
>
> Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@xxxxxxx>

Reviewed-by: Christian König <christian.koenig@xxxxxxx>

> ---
>   .../gpu/drm/amd/amdgpu/amdgpu_userq_fence.c   | 44 ++++++++++++-------
>   .../gpu/drm/amd/amdgpu/amdgpu_userq_fence.h   |  2 +-
>   drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c |  6 +--
>   .../gpu/drm/amd/include/amdgpu_userqueue.h    |  2 +-
>   4 files changed, 32 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> index 8d2a0331cd96..f3576c31428c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> @@ -76,7 +76,8 @@ int amdgpu_userq_fence_driver_alloc(struct amdgpu_device *adev,
>   	fence_drv = kzalloc(sizeof(*fence_drv), GFP_KERNEL);
>   	if (!fence_drv) {
>   		DRM_ERROR("Failed to allocate memory for fence driver\n");
> -		return -ENOMEM;
> +		r = -ENOMEM;
> +		goto free_fence_drv;
>   	}
>   
>   	/* Acquire seq64 memory */
> @@ -84,7 +85,8 @@ int amdgpu_userq_fence_driver_alloc(struct amdgpu_device *adev,
>   			       &fence_drv->cpu_addr);
>   	if (r) {
>   		kfree(fence_drv);
> -		return -ENOMEM;
> +		r = -ENOMEM;
> +		goto free_seq64;
>   	}
>   
>   	memset(fence_drv->cpu_addr, 0, sizeof(u64));
> @@ -94,7 +96,7 @@ int amdgpu_userq_fence_driver_alloc(struct amdgpu_device *adev,
>   	spin_lock_init(&fence_drv->fence_list_lock);
>   
>   	fence_drv->adev = adev;
> -	fence_drv->uq_fence_drv_xa_ref = &userq->uq_fence_drv_xa;
> +	fence_drv->fence_drv_xa_ptr = &userq->fence_drv_xa;
>   	fence_drv->context = dma_fence_context_alloc(1);
>   	get_task_comm(fence_drv->timeline_name, current);
>   
> @@ -106,6 +108,13 @@ int amdgpu_userq_fence_driver_alloc(struct amdgpu_device *adev,
>   	userq->fence_drv = fence_drv;
>   
>   	return 0;
> +
> +free_seq64:
> +	amdgpu_seq64_free(adev, fence_drv->gpu_addr);
> +free_fence_drv:
> +	kfree(fence_drv);
> +
> +	return r;
>   }
>   
>   void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_drv)
> @@ -147,7 +156,7 @@ void amdgpu_userq_fence_driver_destroy(struct kref *ref)
>   	struct amdgpu_device *adev = fence_drv->adev;
>   	struct amdgpu_userq_fence *fence, *tmp;
>   	struct xarray *xa = &adev->userq_xa;
> -	unsigned long index;
> +	unsigned long index, flags;
>   	struct dma_fence *f;
>   
>   	spin_lock(&fence_drv->fence_list_lock);
> @@ -164,11 +173,11 @@ void amdgpu_userq_fence_driver_destroy(struct kref *ref)
>   	}
>   	spin_unlock(&fence_drv->fence_list_lock);
>   
> -	xa_lock(xa);
> +	xa_lock_irqsave(xa, flags);
>   	xa_for_each(xa, index, xa_fence_drv)
>   		if (xa_fence_drv == fence_drv)
>   			__xa_erase(xa, index);
> -	xa_unlock(xa);
> +	xa_unlock_irqrestore(xa, flags);
>   
>   	/* Free seq64 memory */
>   	amdgpu_seq64_free(adev, fence_drv->gpu_addr);
> @@ -212,12 +221,12 @@ int amdgpu_userq_fence_create(struct amdgpu_usermode_queue *userq,
>   	amdgpu_userq_fence_driver_get(fence_drv);
>   	dma_fence_get(fence);
>   
> -	if (!xa_empty(&userq->uq_fence_drv_xa)) {
> +	if (!xa_empty(&userq->fence_drv_xa)) {
>   		struct amdgpu_userq_fence_driver *stored_fence_drv;
>   		unsigned long index, count = 0;
>   		int i = 0;
>   
> -		xa_for_each(&userq->uq_fence_drv_xa, index, stored_fence_drv)
> +		xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv)
>   			count++;
>   
>   		userq_fence->fence_drv_array =
> @@ -226,9 +235,9 @@ int amdgpu_userq_fence_create(struct amdgpu_usermode_queue *userq,
>   				       GFP_KERNEL);
>   
>   		if (userq_fence->fence_drv_array) {
> -			xa_for_each(&userq->uq_fence_drv_xa, index, stored_fence_drv) {
> +			xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv) {
>   				userq_fence->fence_drv_array[i] = stored_fence_drv;
> -				xa_erase(&userq->uq_fence_drv_xa, index);
> +				xa_erase(&userq->fence_drv_xa, index);
>   				i++;
>   			}
>   		}
> @@ -378,7 +387,6 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data,
>   	struct drm_exec exec;
>   	u64 wptr;
>   
> -	/* Array of syncobj handles */
>   	num_syncobj_handles = args->num_syncobj_handles;
>   	syncobj_handles = memdup_user(u64_to_user_ptr(args->syncobj_handles_array),
>   				      sizeof(u32) * num_syncobj_handles);
> @@ -400,7 +408,6 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data,
>   		}
>   	}
>   
> -	/* Array of bo handles */
>   	num_bo_handles = args->num_bo_handles;
>   	bo_handles = memdup_user(u64_to_user_ptr(args->bo_handles_array),
>   				 sizeof(u32) * num_bo_handles);
> @@ -422,7 +429,9 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data,
>   		}
>   	}
>   
> -	drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, 0);
> +	drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, num_bo_handles);
> +
> +	/* Lock all BOs with retry handling */
>   	drm_exec_until_all_locked(&exec) {
>   		r = drm_exec_prepare_array(&exec, gobj, num_bo_handles, 1);
>   		drm_exec_retry_on_contention(&exec);
> @@ -527,7 +536,6 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
>   		goto free_timeline_handles;
>   	}
>   
> -	/* Array of GEM object handles */
>   	gobj = kmalloc_array(num_bo_handles, sizeof(*gobj), GFP_KERNEL);
>   	if (!gobj) {
>   		r = -ENOMEM;
> @@ -542,7 +550,9 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
>   		}
>   	}
>   
> -	drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, 0);
> +	drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, num_bo_handles);
> +
> +	/* Lock all BOs with retry handling */
>   	drm_exec_until_all_locked(&exec) {
>   		r = drm_exec_prepare_array(&exec, gobj, num_bo_handles, 0);
>   		drm_exec_retry_on_contention(&exec);
> @@ -702,8 +712,8 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
>   			 * Otherwise, we would gather those references until we don't
>   			 * have any more space left and crash.
>   			 */
> -			if (fence_drv->uq_fence_drv_xa_ref) {
> -				r = xa_alloc(fence_drv->uq_fence_drv_xa_ref, &index, fence_drv,
> +			if (fence_drv->fence_drv_xa_ptr) {
> +				r = xa_alloc(fence_drv->fence_drv_xa_ptr, &index, fence_drv,
>   					     xa_limit_32b, GFP_KERNEL);
>   				if (r)
>   					goto free_fences;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h
> index f72424248cc5..89c82ba38b50 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h
> @@ -54,7 +54,7 @@ struct amdgpu_userq_fence_driver {
>   	spinlock_t fence_list_lock;
>   	struct list_head fences;
>   	struct amdgpu_device *adev;
> -	struct xarray *uq_fence_drv_xa_ref;
> +	struct xarray *fence_drv_xa_ptr;
>   	char timeline_name[TASK_COMM_LEN];
>   };
>   
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> index e7f7354e0c0e..9b24218f7ad2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
> @@ -48,8 +48,8 @@ static void amdgpu_userq_walk_and_drop_fence_drv(struct xarray *xa)
>   static void
>   amdgpu_userq_fence_driver_free(struct amdgpu_usermode_queue *userq)
>   {
> -	amdgpu_userq_walk_and_drop_fence_drv(&userq->uq_fence_drv_xa);
> -	xa_destroy(&userq->uq_fence_drv_xa);
> +	amdgpu_userq_walk_and_drop_fence_drv(&userq->fence_drv_xa);
> +	xa_destroy(&userq->fence_drv_xa);
>   	/* Drop the fence_drv reference held by user queue */
>   	amdgpu_userq_fence_driver_put(userq->fence_drv);
>   }
> @@ -348,7 +348,7 @@ amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq *args)
>   	}
>   	queue->doorbell_index = index;
>   
> -	xa_init_flags(&queue->uq_fence_drv_xa, XA_FLAGS_ALLOC);
> +	xa_init_flags(&queue->fence_drv_xa, XA_FLAGS_ALLOC);
>   	r = amdgpu_userq_fence_driver_alloc(adev, queue);
>   	if (r) {
>   		DRM_ERROR("Failed to alloc fence driver\n");
> diff --git a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
> index d035b5c2b14b..6eb094a54f4b 100644
> --- a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
> +++ b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
> @@ -52,7 +52,7 @@ struct amdgpu_usermode_queue {
>   	struct amdgpu_userq_obj	db_obj;
>   	struct amdgpu_userq_obj fw_obj;
>   	struct amdgpu_userq_obj wptr_obj;
> -	struct xarray		uq_fence_drv_xa;
> +	struct xarray		fence_drv_xa;
>   	struct amdgpu_userq_fence_driver *fence_drv;
>   	struct dma_fence	*last_fence;
>   };