Re: [PATCH v1 18/29] cxl/region: Avoid duplicate call of cxl_find_decoder_early()

[Gregory Price <gourry@gourry.net>]

On Tue, Jan 07, 2025 at 03:10:04PM +0100, Robert Richter wrote:
> Function cxl_find_decoder_early() is called twice, in
> alloc_region_ref() and cxl_rr_alloc_decoder(). Move it out there and
> instead pass the decoder as function argument to both.
> 
> Signed-off-by: Robert Richter <rrichter@amd.com>
> ---
>  drivers/cxl/core/region.c | 31 +++++++++++++++----------------
>  1 file changed, 15 insertions(+), 16 deletions(-)
>

Reviewed-by: Gregory Price <gourry@gourry.net>

> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 2bc2028988d3..b7f6d8a83e4e 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -928,7 +928,8 @@ static bool auto_order_ok(struct cxl_port *port, struct cxl_region *cxlr_iter,
>  
>  static struct cxl_region_ref *
>  alloc_region_ref(struct cxl_port *port, struct cxl_region *cxlr,
> -		 struct cxl_endpoint_decoder *cxled)
> +		 struct cxl_endpoint_decoder *cxled,
> +		 struct cxl_decoder *cxld)
>  {
>  	struct cxl_region_params *p = &cxlr->params;
>  	struct cxl_region_ref *cxl_rr, *iter;
> @@ -942,9 +943,6 @@ alloc_region_ref(struct cxl_port *port, struct cxl_region *cxlr,
>  			continue;
>  
>  		if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) {
> -			struct cxl_decoder *cxld;
> -
> -			cxld = cxl_find_decoder_early(port, cxled, cxlr);
>  			if (auto_order_ok(port, iter->region, cxld))
>  				continue;
>  		}
> @@ -1028,17 +1026,9 @@ static int cxl_rr_ep_add(struct cxl_region_ref *cxl_rr,
>  
>  static int cxl_rr_alloc_decoder(struct cxl_port *port, struct cxl_region *cxlr,
>  				struct cxl_endpoint_decoder *cxled,
> -				struct cxl_region_ref *cxl_rr)
> +				struct cxl_region_ref *cxl_rr,
> +				struct cxl_decoder *cxld)
>  {
> -	struct cxl_decoder *cxld;
> -
> -	cxld = cxl_find_decoder_early(port, cxled, cxlr);
> -	if (!cxld) {
> -		dev_dbg(&cxlr->dev, "%s: no decoder available\n",
> -			dev_name(&port->dev));
> -		return -EBUSY;
> -	}
> -
>  	if (cxld->region) {
>  		dev_dbg(&cxlr->dev, "%s: %s already attached to %s\n",
>  			dev_name(&port->dev), dev_name(&cxld->dev),
> @@ -1129,7 +1119,16 @@ static int cxl_port_attach_region(struct cxl_port *port,
>  			nr_targets_inc = true;
>  		}
>  	} else {
> -		cxl_rr = alloc_region_ref(port, cxlr, cxled);
> +		struct cxl_decoder *cxld;
> +
> +		cxld = cxl_find_decoder_early(port, cxled, cxlr);
> +		if (!cxld) {
> +			dev_dbg(&cxlr->dev, "%s: no decoder available\n",
> +				dev_name(&port->dev));
> +			return -EBUSY;
> +		}
> +
> +		cxl_rr = alloc_region_ref(port, cxlr, cxled, cxld);
>  		if (IS_ERR(cxl_rr)) {
>  			dev_dbg(&cxlr->dev,
>  				"%s: failed to allocate region reference\n",
> @@ -1138,7 +1137,7 @@ static int cxl_port_attach_region(struct cxl_port *port,
>  		}
>  		nr_targets_inc = true;
>  
> -		rc = cxl_rr_alloc_decoder(port, cxlr, cxled, cxl_rr);
> +		rc = cxl_rr_alloc_decoder(port, cxlr, cxled, cxl_rr, cxld);
>  		if (rc)
>  			goto out_erase;
>  	}
> -- 
> 2.39.5
>