Subject: Re: [PATCH net-next v3 10/12] selftests: ncdevmem: Run selftest when none of the -s or -c has been provided

From: Stanislav Fomichev <[email-masked]>
Date: Wed, 9 Oct 2024 21:19:44 -0700

On 10/09, Stanislav Fomichev wrote:
> This will be used as a 'probe' mode in the selftest to check whether
> the device supports the devmem or not. Use hard-coded queue layout
> (two last queues) and prevent user from passing custom -q and/or -t.
> 
> Cc: Mina Almasry <[email-masked]>
> Signed-off-by: Stanislav Fomichev <[email-masked]>
> ---
>  tools/testing/selftests/net/ncdevmem.c | 42 ++++++++++++++++++++------
>  1 file changed, 32 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/testing/selftests/net/ncdevmem.c b/tools/testing/selftests/net/ncdevmem.c
> index 90aacfb3433f..3a456c058241 100644
> --- a/tools/testing/selftests/net/ncdevmem.c
> +++ b/tools/testing/selftests/net/ncdevmem.c
> @@ -64,7 +64,7 @@ static char *client_ip;
>  static char *port;
>  static size_t do_validation;
>  static int start_queue = -1;
> -static int num_queues = 1;
> +static int num_queues = -1;
>  static char *ifname;
>  static unsigned int ifindex;
>  static unsigned int dmabuf_id;
> @@ -706,19 +706,31 @@ int main(int argc, char *argv[])
>  		}
>  	}
>  
> -	if (!server_ip)
> -		error(1, 0, "Missing -s argument\n");
> -
> -	if (!port)
> -		error(1, 0, "Missing -p argument\n");
> -
>  	if (!ifname)
>  		error(1, 0, "Missing -f argument\n");
>  
>  	ifindex = if_nametoindex(ifname);
>  
> -	if (start_queue < 0) {
> -		start_queue = rxq_num(ifindex) - 1;
> +	if (!server_ip && !client_ip) {
> +		if (start_queue < 0 && num_queues < 0) {
> +			num_queues = rxq_num(ifindex);
> +			if (num_queues < 0)
> +				error(1, 0, "couldn't detect number of queues\n");
> +			/* make sure can bind to multiple queues */

[..]

> +			start_queues = num_queues / 2;

Should have been start_queue, not start_queues. Not sure how I missed
that. Also means I haven't run this for real..