[Intel-gfx] [PATCH 1/2] Revert "dma-buf: Report signaled links inside dma-fence-chain"

[Christian König]

Am 25.06.20 um 14:34 schrieb Lionel Landwerlin:
> This reverts commit 5de376bb434f80a13138f0ebedc8351ab73d8b0d.
>
> This change breaks synchronization of a timeline.
> dma_fence_chain_find_seqno() might be a bit of a confusing name but
> this function is not trying to find a particular seqno, is supposed to
> give a fence to wait on for a particular point in the timeline.
>
> In a timeline, a particular value is reached when all the points up to
> and including that value have signaled.
>
> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>

Reviewed-by: Christian König <christian.koenig at amd.com>

> ---
>   drivers/dma-buf/dma-fence-chain.c | 7 -------
>   1 file changed, 7 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-fence-chain.c b/drivers/dma-buf/dma-fence-chain.c
> index c435bbba851c..3d123502ff12 100644
> --- a/drivers/dma-buf/dma-fence-chain.c
> +++ b/drivers/dma-buf/dma-fence-chain.c
> @@ -99,12 +99,6 @@ int dma_fence_chain_find_seqno(struct dma_fence **pfence, uint64_t seqno)
>   		return -EINVAL;
>   
>   	dma_fence_chain_for_each(*pfence, &chain->base) {
> -		if ((*pfence)->seqno < seqno) { /* already signaled */
> -			dma_fence_put(*pfence);
> -			*pfence = NULL;
> -			break;
> -		}
> -
>   		if ((*pfence)->context != chain->base.context ||
>   		    to_dma_fence_chain(*pfence)->prev_seqno < seqno)
>   			break;
> @@ -228,7 +222,6 @@ EXPORT_SYMBOL(dma_fence_chain_ops);
>    * @chain: the chain node to initialize
>    * @prev: the previous fence
>    * @fence: the current fence
> - * @seqno: the sequence number (syncpt) of the fence within the chain
>    *
>    * Initialize a new chain node and either start a new chain or add the node to
>    * the existing chain of the previous fence.