Re: [PATCH RFC net-next 1/2] netconsole: extract message fragmentation into write_msg_target()

[Petr Mladek <pmladek@suse.com>]

On Fri 2025-11-21 03:26:07, Breno Leitao wrote:
> Refactor the message fragmentation logic in write_msg() by extracting it
> into a separate write_msg_target() helper function. This makes the code
> more maintainable and prepares for future reuse in nbcon support for
> non-extended consoles.
> 
> The helper function takes a target, message, and length, then handles
> splitting the message into MAX_PRINT_CHUNK-sized fragments for sending
> via send_udp().
> 
> No functional change intended.

> --- a/drivers/net/netconsole.c
> +++ b/drivers/net/netconsole.c
> @@ -1559,6 +1559,20 @@ static void append_release(char *buf)
>  	scnprintf(buf, MAX_PRINT_CHUNK, "%s,", release);
>  }
>  
> +static void write_msg_target(struct netconsole_target *nt, const char *msg,
> +			     unsigned int len)
> +{
> +	const char *tmp = msg;
> +	int frag, left = len;
> +
> +	while (left > 0) {
> +		frag = min(left, MAX_PRINT_CHUNK);
> +		send_udp(nt, tmp, frag);
> +		tmp += frag;
> +		left -= frag;
> +	}
> +}
> +
>  static void send_fragmented_body(struct netconsole_target *nt,
>  				 const char *msgbody, int header_len,
>  				 int msgbody_len, int extradata_len)
> @@ -1748,13 +1760,7 @@ static void write_msg(struct console *con, const char *msg, unsigned int len)
>  			 * at least one target if we die inside here, instead
>  			 * of unnecessarily keeping all targets in lock-step.
>  			 */
> -			tmp = msg;
> -			for (left = len; left;) {
> -				frag = min(left, MAX_PRINT_CHUNK);
> -				send_udp(nt, tmp, frag);
> -				tmp += frag;
> -				left -= frag;
> -			}
> +			write_msg_target(nt, msg, len);

I would call the new function send_msg_udp() to make it symetric with:

static void write_ext_msg(struct console *con, const char *msg,
			  unsigned int len)
{
[...]
			send_ext_msg_udp(nt, msg, len);
[...]
}

By other words, use "write_*()" when struct console * is passed
and send_*_udp() when struct netconsole_target * is passed.

The inconsistence confused me... ;-)

Note that write_msg()/write_ext_msg() are cut&pasted.
The only difference would be send_msg_udp()/send_ext_msg_udp().

>  		}
>  	}
>  	spin_unlock_irqrestore(&target_list_lock, flags);

Otherwise, I confirm that it is just a refactoring with no
functional change.

Feel free to use, ideally after the renaming function:

Reviewed-by: Petr Mladek <pmladek@suse.com>

Best Regards,
Petr