Re: [bpf-next, v2] samples: bpf: add max_pckt_size option at xdp_adjust_tail

[Song Liu]

On Mon, Aug 26, 2019 at 9:52 AM Daniel T. Lee <danieltim...@gmail.com> wrote:
>
> Currently, at xdp_adjust_tail_kern.c, MAX_PCKT_SIZE is limited
> to 600. To make this size flexible, a new map 'pcktsz' is added.
>
> By updating new packet size to this map from the userland,
> xdp_adjust_tail_kern.o will use this value as a new max_pckt_size.
>
> If no '-P <MAX_PCKT_SIZE>' option is used, the size of maximum packet
> will be 600 as a default.

Please also cc b...@vger.kernel.org for bpf patches.

>
> Signed-off-by: Daniel T. Lee <danieltim...@gmail.com>

Acked-by: Song Liu <songliubrav...@fb.com>

With a nit below.

[...]

> diff --git a/samples/bpf/xdp_adjust_tail_user.c 
> b/samples/bpf/xdp_adjust_tail_user.c
> index a3596b617c4c..29ade7caf841 100644
> --- a/samples/bpf/xdp_adjust_tail_user.c
> +++ b/samples/bpf/xdp_adjust_tail_user.c
> @@ -72,6 +72,7 @@ static void usage(const char *cmd)
>         printf("Usage: %s [...]\n", cmd);
>         printf("    -i <ifname|ifindex> Interface\n");
>         printf("    -T <stop-after-X-seconds> Default: 0 (forever)\n");
> +       printf("    -P <MAX_PCKT_SIZE> Default: 600\n");

nit: printf("    -P <MAX_PCKT_SIZE> Default: %u\n", MAX_PCKT_SIZE);