On 04/15/16 at 08:28pm, Roopa Prabhu wrote:
> +static size_t inet6_get_link_af_stats_size(const struct net_device *dev,
> + u32 filter_mask)
> +{
> + if (!(filter_mask & IFLA_STATS_FILTER_BIT(IFLA_STATS_LINK_INET6)))
> + return 0;
> +
> + if (!__in6_dev_get(dev))
> + return 0;
> +
> + return nla_total_size(sizeof(struct nlattr)) /* IFLA_STATS_LINK_INET6 */
> + + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
> + + nla_total_size(ICMP6_MIB_MAX * sizeof(u64));/*
> IFLA_INET6_ICMP6STATS */
> +}
I think this is a good example. The above is an expensive way to
figure out whether you have at least one interface with IPv6
statistics. I'd suggest to turn this into:
if (filter_mask & IFLA_STATS_FILTER_BIT(IFLA_STATS_LINK_INET6)) {
size += nla_total_size(sizeof(struct nlattr)) /* IFLA_STATS_LINK_INET6
*/
+ nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
+ nla_total_size(ICMP6_MIB_MAX * sizeof(u64));/*
IFLA_INET6_ICMP6STATS */
}
... and put it into the main calcit function. The user has explicitly opted into
IPv6 statistics so I think it's not a waste to allocate resources for it in the
message. You could also make it depend on "disable_ipv6" to be more accurate but
I think even the above is good enough.
