Re: [PATCH 16/24] drm/nouveau: support more than one write fence in fenv50_wndw_prepare_fb

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, Dec 07, 2021 at 01:34:03PM +0100, Christian König wrote:
> Use dma_resv_get_singleton() here to eventually get more than one write
> fence as single fence.
> 
> Signed-off-by: Christian König <christian.koenig@amd.com>
> ---
>  drivers/gpu/drm/nouveau/dispnv50/wndw.c | 14 +++++---------
>  1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/wndw.c b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
> index 133c8736426a..b55a8a723581 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/wndw.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
> @@ -536,8 +536,6 @@ nv50_wndw_prepare_fb(struct drm_plane *plane, struct drm_plane_state *state)
>  	struct nouveau_bo *nvbo;
>  	struct nv50_head_atom *asyh;
>  	struct nv50_wndw_ctxdma *ctxdma;
> -	struct dma_resv_iter cursor;
> -	struct dma_fence *fence;
>  	int ret;
>  
>  	NV_ATOMIC(drm, "%s prepare: %p\n", plane->name, fb);
> @@ -560,13 +558,11 @@ nv50_wndw_prepare_fb(struct drm_plane *plane, struct drm_plane_state *state)
>  			asyw->image.handle[0] = ctxdma->object.handle;
>  	}
>  
> -	dma_resv_iter_begin(&cursor, nvbo->bo.base.resv, false);
> -	dma_resv_for_each_fence_unlocked(&cursor, fence) {
> -		/* TODO: We only use the first writer here */
> -		asyw->state.fence = dma_fence_get(fence);
> -		break;
> -	}
> -	dma_resv_iter_end(&cursor);
> +	ret = dma_resv_get_singleton(nvbo->bo.base.resv, false,
> +				     &asyw->state.fence);

Needs nouveau-ack, but otherwise lgtm.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> +	if (ret)
> +		return ret;
> +
>  	asyw->image.offset[0] = nvbo->offset;
>  
>  	if (wndw->func->prepare) {
> -- 
> 2.25.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch