[Intel-gfx] [PATCH 5/6] dma-buf: add dma_fence_chain_contained helper

[Thomas Hellström]

On Fri, 2022-02-04 at 11:04 +0100, Christian König wrote:
> It's a reoccurring pattern that we need to extract the fence
> from a dma_fence_chain object. Add a helper for this.
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>

I thought I'd reviewed this one already, but in case I didn't

Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>


> ---
>  drivers/dma-buf/dma-fence-chain.c |  6 ++----
>  include/linux/dma-fence-chain.h   | 15 +++++++++++++++
>  2 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma-buf/dma-fence-chain.c b/drivers/dma-buf/dma-
> fence-chain.c
> index 084c6927b735..06f8ef97c6e8 100644
> --- a/drivers/dma-buf/dma-fence-chain.c
> +++ b/drivers/dma-buf/dma-fence-chain.c
> @@ -148,8 +148,7 @@ static bool
> dma_fence_chain_enable_signaling(struct dma_fence *fence)
>  
>         dma_fence_get(&head->base);
>         dma_fence_chain_for_each(fence, &head->base) {
> -               struct dma_fence_chain *chain =
> to_dma_fence_chain(fence);
> -               struct dma_fence *f = chain ? chain->fence : fence;
> +               struct dma_fence *f =
> dma_fence_chain_contained(fence);
>  
>                 dma_fence_get(f);
>                 if (!dma_fence_add_callback(f, &head->cb,
> dma_fence_chain_cb)) {
> @@ -165,8 +164,7 @@ static bool
> dma_fence_chain_enable_signaling(struct dma_fence *fence)
>  static bool dma_fence_chain_signaled(struct dma_fence *fence)
>  {
>         dma_fence_chain_for_each(fence, fence) {
> -               struct dma_fence_chain *chain =
> to_dma_fence_chain(fence);
> -               struct dma_fence *f = chain ? chain->fence : fence;
> +               struct dma_fence *f =
> dma_fence_chain_contained(fence);
>  
>                 if (!dma_fence_is_signaled(f)) {
>                         dma_fence_put(fence);
> diff --git a/include/linux/dma-fence-chain.h b/include/linux/dma-
> fence-chain.h
> index ee906b659694..10d51bcdf7b7 100644
> --- a/include/linux/dma-fence-chain.h
> +++ b/include/linux/dma-fence-chain.h
> @@ -66,6 +66,21 @@ to_dma_fence_chain(struct dma_fence *fence)
>         return container_of(fence, struct dma_fence_chain, base);
>  }
>  
> +/**
> + * dma_fence_chain_contained - return the contained fence
> + * @fence: the fence to test
> + *
> + * If the fence is a dma_fence_chain the function returns the fence
> contained
> + * inside the chain object, otherwise it returns the fence itself.
> + */
> +static inline struct dma_fence *
> +dma_fence_chain_contained(struct dma_fence *fence)
> +{
> +       struct dma_fence_chain *chain = to_dma_fence_chain(fence);
> +
> +       return chain ? chain->fence : fence;
> +}
> +
>  /**
>   * dma_fence_chain_alloc
>   *