Subject: Re: [PATCH net-next] net: freescale: use ethtool string helpers

From: Simon Horman <[email-masked]>
Date: Fri, 25 Oct 2024 13:57:04 +0100

On Thu, Oct 24, 2024 at 01:52:57PM -0700, Rosen Penev wrote:
> The latter is the preferred way to copy ethtool strings.
> 
> Avoids manually incrementing the pointer. Cleans up the code quite well.
> 
> Signed-off-by: Rosen Penev <[email-masked]>

...

> diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c b/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
> index b0060cf96090..10c5fa4d23d2 100644
> --- a/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
> +++ b/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
> @@ -243,38 +243,24 @@ static void dpaa_get_ethtool_stats(struct net_device *net_dev,
>  static void dpaa_get_strings(struct net_device *net_dev, u32 stringset,
>  			     u8 *data)
>  {
> -	unsigned int i, j, num_cpus, size;
> -	char string_cpu[ETH_GSTRING_LEN];
> -	u8 *strings;
> +	unsigned int i, j, num_cpus;
>  
> -	memset(string_cpu, 0, sizeof(string_cpu));
> -	strings   = data;
> -	num_cpus  = num_online_cpus();
> -	size      = DPAA_STATS_GLOBAL_LEN * ETH_GSTRING_LEN;
> +	num_cpus = num_online_cpus();
>  
>  	for (i = 0; i < DPAA_STATS_PERCPU_LEN; i++) {
> -		for (j = 0; j < num_cpus; j++) {
> -			snprintf(string_cpu, ETH_GSTRING_LEN, "%s [CPU %d]",
> -				 dpaa_stats_percpu[i], j);
> -			memcpy(strings, string_cpu, ETH_GSTRING_LEN);
> -			strings += ETH_GSTRING_LEN;
> -		}
> -		snprintf(string_cpu, ETH_GSTRING_LEN, "%s [TOTAL]",
> -			 dpaa_stats_percpu[i]);
> -		memcpy(strings, string_cpu, ETH_GSTRING_LEN);
> -		strings += ETH_GSTRING_LEN;
> -	}
> -	for (j = 0; j < num_cpus; j++) {
> -		snprintf(string_cpu, ETH_GSTRING_LEN,
> -			 "bpool [CPU %d]", j);
> -		memcpy(strings, string_cpu, ETH_GSTRING_LEN);
> -		strings += ETH_GSTRING_LEN;
> +		for (j = 0; j < num_cpus; j++)
> +			ethtool_sprintf(&data, "%s [CPU %d]",
> +					dpaa_stats_percpu[i], j);
> +
> +		ethtool_sprintf(&data, "%s [TOTAL]", dpaa_stats_percpu[i]);
>  	}
> -	snprintf(string_cpu, ETH_GSTRING_LEN, "bpool [TOTAL]");
> -	memcpy(strings, string_cpu, ETH_GSTRING_LEN);
> -	strings += ETH_GSTRING_LEN;
> +	for (i = 0; j < num_cpus; i++)

Perhaps this should consistently use i, rather than i and j:

	for (i = 0; i < num_cpus; i++)

Flagged by W=1 builds with clang-18.

> +		ethtool_sprintf(&data, "bpool [CPU %d]", i);
> +
> +	ethtool_puts(&data, "bpool [TOTAL]");
>  
> -	memcpy(strings, dpaa_stats_global, size);
> +	for (i = 0; i < DPAA_STATS_GLOBAL_LEN; i++)
> +		ethtool_puts(&data, dpaa_stats_global[i]);
>  }
>  
>  static int dpaa_get_hash_opts(struct net_device *dev,

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