Subject: Re: [Cake] [PATCH net-next v2] Add Common Applications Kept Enhanced (cake) qdisc

From: Stephen Hemminger <[email-masked]>
Date: Tue, 24 Apr 2018 08:11:26 -0700

On Tue, 24 Apr 2018 13:44:06 +0200
Toke Høiland-Jørgensen <[email-masked]> wrote:

> +struct tc_cake_xstats {
> +	__u16 version;
> +	__u16 tin_stats_size; /* == sizeof(struct tc_cake_tin_stats) */
> +	__u32 capacity_estimate;
> +	__u32 memory_limit;
> +	__u32 memory_used;
> +	__u8  tin_cnt;
> +	__u8  avg_trnoff;
> +	__u16 max_netlen;
> +	__u16 max_adjlen;
> +	__u16 min_netlen;
> +	__u16 min_adjlen;
> +
> +	__u16 spare1;
> +	__u32 spare2;
> +
> +	struct tc_cake_tin_stats tin_stats[0]; /* keep last */
> +};

No versioning allowed in userspace API. You need to drop version and make
it permanent.