Re: [PATCH net-next 09/18] ravb: Factorise ravb_ring_free function

From: Sergei Shtylyov <sergei.shtylyov@gmail.com>
To: Biju Das <biju.das.jz@bp.renesas.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>,
	Sergey Shtylyov <s.shtylyov@omprussia.ru>,
	Adam Ford <aford173@gmail.com>, Andrew Lunn <andrew@lunn.ch>,
	Yuusuke Ashizuka <ashiduka@fujitsu.com>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	Chris Paterson <Chris.Paterson2@renesas.com>,
	Biju Das <biju.das@bp.renesas.com>,
	Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Subject: Re: [PATCH net-next 09/18] ravb: Factorise ravb_ring_free function
Date: Thu, 29 Jul 2021 21:02:45 +0300	[thread overview]
Message-ID: <a0d1bb7e-0e0a-8237-c30a-e4533b5580dd@gmail.com> (raw)
In-Reply-To: <20210722141351.13668-10-biju.das.jz@bp.renesas.com>

Hello!

On 7/22/21 5:13 PM, Biju Das wrote:

> Extended descriptor support in RX is available for R-Car where as it
> is a normal descriptor for RZ/G2L. Factorise ravb_ring_free function
> so that it can support later SoC.
> 
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>  drivers/net/ethernet/renesas/ravb.h      |  5 +++
>  drivers/net/ethernet/renesas/ravb_main.c | 49 ++++++++++++++++--------
>  2 files changed, 37 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
> index a474ed68db22..3a9cf6e8671a 100644
> --- a/drivers/net/ethernet/renesas/ravb.h
> +++ b/drivers/net/ethernet/renesas/ravb.h
> @@ -988,7 +988,12 @@ enum ravb_chip_id {
>  	RCAR_GEN3,
>  };
>  
> +struct ravb_ops {
> +	void (*ring_free)(struct net_device *ndev, int q);

   Hmm, why not store it right in the *struct* ravb_drv_data?

> +};
> +
>  struct ravb_drv_data {
> +	const struct ravb_ops *ravb_ops;
>  	netdev_features_t net_features;
>  	netdev_features_t net_hw_features;
>  	const char (*gstrings_stats)[ETH_GSTRING_LEN];
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 4ef2565534d2..a3b8b243fd54 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -247,30 +247,39 @@ static int ravb_tx_free(struct net_device *ndev, int q, bool free_txed_only)
>  }
>  
>  /* Free skb's and DMA buffers for Ethernet AVB */
> -static void ravb_ring_free(struct net_device *ndev, int q)
> +static void ravb_ring_free_rx(struct net_device *ndev, int q)

   How about ravb_rx_ring_free() instead?

>  {
>  	struct ravb_private *priv = netdev_priv(ndev);
> -	int num_tx_desc = priv->num_tx_desc;
>  	int ring_size;
>  	int i;
>  
> -	if (priv->rx_ring[q]) {
> -		for (i = 0; i < priv->num_rx_ring[q]; i++) {
> -			struct ravb_ex_rx_desc *desc = &priv->rx_ring[q][i];
> +	for (i = 0; i < priv->num_rx_ring[q]; i++) {
> +		struct ravb_ex_rx_desc *desc = &priv->rx_ring[q][i];
>  
> -			if (!dma_mapping_error(ndev->dev.parent,
> -					       le32_to_cpu(desc->dptr)))
> -				dma_unmap_single(ndev->dev.parent,
> -						 le32_to_cpu(desc->dptr),
> -						 RX_BUF_SZ,
> -						 DMA_FROM_DEVICE);
> -		}
> -		ring_size = sizeof(struct ravb_ex_rx_desc) *
> -			    (priv->num_rx_ring[q] + 1);
> -		dma_free_coherent(ndev->dev.parent, ring_size, priv->rx_ring[q],
> -				  priv->rx_desc_dma[q]);
> -		priv->rx_ring[q] = NULL;
> +		if (!dma_mapping_error(ndev->dev.parent,
> +				       le32_to_cpu(desc->dptr)))
> +			dma_unmap_single(ndev->dev.parent,
> +					 le32_to_cpu(desc->dptr),
> +					 RX_BUF_SZ,
> +					 DMA_FROM_DEVICE);
>  	}
> +	ring_size = sizeof(struct ravb_ex_rx_desc) *
> +		    (priv->num_rx_ring[q] + 1);
> +	dma_free_coherent(ndev->dev.parent, ring_size, priv->rx_ring[q],
> +			  priv->rx_desc_dma[q]);
> +	priv->rx_ring[q] = NULL;

   Couldn't this be moved into the new ravb_ring_free(), like the initial NULL check?

> +}
> +
> +static void ravb_ring_free(struct net_device *ndev, int q)
> +{
> +	struct ravb_private *priv = netdev_priv(ndev);
> +	const struct ravb_drv_data *info = priv->info;
> +	int num_tx_desc = priv->num_tx_desc;
> +	int ring_size;
> +	int i;
> +
> +	if (priv->rx_ring[q])
> +		info->ravb_ops->ring_free(ndev, q);

   ... here?

[...]

MBR, Sergei