Re: [PATCH v3 1/4] drm/ttm: Create pinned list

[Christian König <christian.koenig@xxxxxxx>]

Am 27.08.21 um 22:39 schrieb Andrey Grodzovsky:
> This list will be used to capture all non VRAM BOs not
> on LRU so when device is hot unplugged we can iterate
> the list and unmap DMA mappings before device is removed.
>
> v2: Reanme function to ttm_bo_move_to_pinned
> v3: Move the pinned list to ttm device

As far as I can see there is not list_del() remaining. So this won't 
work correctly.

I suggest to rather rebase on top of the stuff I'm working on for a 
while to move the LRU into the resource instead.

Just send out the latest patch set of this with you in CC.

Christian.

> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
> Suggested-by: Christian König <christian.koenig@xxxxxxx>
> ---
>   drivers/gpu/drm/ttm/ttm_bo.c     | 18 ++++++++++++++----
>   drivers/gpu/drm/ttm/ttm_device.c |  1 +
>   include/drm/ttm/ttm_device.h     |  1 +
>   3 files changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index 1b950b45cf4b..1fedd0eb67ba 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -69,7 +69,17 @@ static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
>   	}
>   }
>   
> -static void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
> +static inline void ttm_bo_move_to_pinned(struct ttm_buffer_object *bo)
> +{
> +	struct ttm_device *bdev = bo->bdev;
> +
> +	list_move_tail(&bo->lru, &bdev->pinned);
> +
> +	if (bdev->funcs->del_from_lru_notify)
> +		bdev->funcs->del_from_lru_notify(bo);
> +}
> +
> +static inline void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
>   {
>   	struct ttm_device *bdev = bo->bdev;
>   
> @@ -98,7 +108,7 @@ void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
>   		dma_resv_assert_held(bo->base.resv);
>   
>   	if (bo->pin_count) {
> -		ttm_bo_del_from_lru(bo);
> +		ttm_bo_move_to_pinned(bo);
>   		return;
>   	}
>   
> @@ -339,7 +349,7 @@ static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
>   		return ret;
>   	}
>   
> -	ttm_bo_del_from_lru(bo);
> +	ttm_bo_move_to_pinned(bo);
>   	list_del_init(&bo->ddestroy);
>   	spin_unlock(&bo->bdev->lru_lock);
>   	ttm_bo_cleanup_memtype_use(bo);
> @@ -1154,7 +1164,7 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
>   		return 0;
>   	}
>   
> -	ttm_bo_del_from_lru(bo);
> +	ttm_bo_move_to_pinned(bo);
>   	/* TODO: Cleanup the locking */
>   	spin_unlock(&bo->bdev->lru_lock);
>   
> diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c
> index 5f31acec3ad7..530a9c36be37 100644
> --- a/drivers/gpu/drm/ttm/ttm_device.c
> +++ b/drivers/gpu/drm/ttm/ttm_device.c
> @@ -208,6 +208,7 @@ int ttm_device_init(struct ttm_device *bdev, struct ttm_device_funcs *funcs,
>   	INIT_DELAYED_WORK(&bdev->wq, ttm_device_delayed_workqueue);
>   	spin_lock_init(&bdev->lru_lock);
>   	INIT_LIST_HEAD(&bdev->ddestroy);
> +	INIT_LIST_HEAD(&bdev->pinned);
>   	bdev->dev_mapping = mapping;
>   	mutex_lock(&ttm_global_mutex);
>   	list_add_tail(&bdev->device_list, &glob->device_list);
> diff --git a/include/drm/ttm/ttm_device.h b/include/drm/ttm/ttm_device.h
> index cd592f8e941b..03fb44d061e0 100644
> --- a/include/drm/ttm/ttm_device.h
> +++ b/include/drm/ttm/ttm_device.h
> @@ -265,6 +265,7 @@ struct ttm_device {
>   	 */
>   	spinlock_t lru_lock;
>   	struct list_head ddestroy;
> +	struct list_head pinned;
>   
>   	/*
>   	 * Protected by load / firstopen / lastclose /unload sync.