Re: [PATCH net-next v3 2/3] net: ti: icssg-prueth: introduce and use prueth_swdata struct for SWDATA

[Dan Carpenter <dan.carpenter@linaro.org>]

On Mon, Feb 24, 2025 at 04:31:01PM +0530, Meghana Malladi wrote:
> From: Roger Quadros <rogerq@kernel.org>
> 
> We have different cases for SWDATA (skb, page, cmd, etc)
> so it is better to have a dedicated data structure for that.
> We can embed the type field inside the struct and use it
> to interpret the data in completion handlers.
> 
> Increase SWDATA size to 48 so we have some room to add
> more data if required.

What is the "SWDATA size"?  Where is that specified?  Is
that a variable or a define or the size of a struct or
what?

> 
> Signed-off-by: Roger Quadros <rogerq@kernel.org>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> Signed-off-by: Meghana Malladi <m-malladi@ti.com>
> ---
> Changes since v2 (v3-v2):
> - Fix leaking tx descriptor in emac_tx_complete_packets()
> - Free rx descriptor if swdata type is not page in emac_rx_packet()
> - Revert back the size of PRUETH_NAV_SW_DATA_SIZE
> - Use build time check for prueth_swdata size
> - re-write prueth_swdata to have enum type as first member in the struct
> and prueth_data union embedded in the struct
> 
> All the above changes have been suggested by Roger Quadros <rogerq@kernel.org>
> 
>  drivers/net/ethernet/ti/icssg/icssg_common.c  | 52 +++++++++++++------
>  drivers/net/ethernet/ti/icssg/icssg_prueth.c  |  3 ++
>  drivers/net/ethernet/ti/icssg/icssg_prueth.h  | 16 ++++++
>  .../net/ethernet/ti/icssg/icssg_prueth_sr1.c  |  4 +-
>  4 files changed, 57 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_common.c b/drivers/net/ethernet/ti/icssg/icssg_common.c
> index acbb79ad8b0c..01eeabe83eff 100644
> --- a/drivers/net/ethernet/ti/icssg/icssg_common.c
> +++ b/drivers/net/ethernet/ti/icssg/icssg_common.c
> @@ -136,12 +136,12 @@ int emac_tx_complete_packets(struct prueth_emac *emac, int chn,
>  	struct net_device *ndev = emac->ndev;
>  	struct cppi5_host_desc_t *desc_tx;
>  	struct netdev_queue *netif_txq;
> +	struct prueth_swdata *swdata;
>  	struct prueth_tx_chn *tx_chn;
>  	unsigned int total_bytes = 0;
>  	struct sk_buff *skb;
>  	dma_addr_t desc_dma;
>  	int res, num_tx = 0;
> -	void **swdata;
>  
>  	tx_chn = &emac->tx_chns[chn];
>  
> @@ -163,12 +163,19 @@ int emac_tx_complete_packets(struct prueth_emac *emac, int chn,
>  		swdata = cppi5_hdesc_get_swdata(desc_tx);
>  
>  		/* was this command's TX complete? */
> -		if (emac->is_sr1 && *(swdata) == emac->cmd_data) {
> +		if (emac->is_sr1 && (void *)(swdata) == emac->cmd_data) {

I don't think this conversion is correct.  You still need to say:

		if (emac->is_sr1 && swdata->data.something == emac->cmd_data) {

Where something is probably "page".

regards,
dan carpenter

>  			prueth_xmit_free(tx_chn, desc_tx);
>  			continue;
>  		}
>  
> -		skb = *(swdata);
> +		if (swdata->type != PRUETH_SWDATA_SKB) {
> +			netdev_err(ndev, "tx_complete: invalid swdata type %d\n", swdata->type);
> +			prueth_xmit_free(tx_chn, desc_tx);
> +			budget++;
> +			continue;
> +		}