Subject: Re: [PATCH iproute2 1/2] tc/taprio: don't print netlink attributes which weren't reported by the kernel

From: Vinicius Costa Gomes <[email-masked]>
Date: Mon, 07 Aug 2023 13:15:45 -0700

Vladimir Oltean <[email-masked]> writes:

> When an admin schedule is pending and hasn't yet become operational, the
> kernel will report only the parameters of the admin schedule in a nested
> TCA_TAPRIO_ATTR_ADMIN_SCHED attribute.
>
> However, we default to printing zeroes even for the parameters of the
> operational base time, when that doesn't exist.
>
> Link: https://lore.kernel.org/netdev/[email-masked]/
> Fixes: 0dd16449356f ("tc: Add support for configuring the taprio scheduler")
> Signed-off-by: Vladimir Oltean <[email-masked]>
> ---
>  tc/q_taprio.c | 91 ++++++++++++++++++++++++++++++---------------------
>  1 file changed, 53 insertions(+), 38 deletions(-)
>
> diff --git a/tc/q_taprio.c b/tc/q_taprio.c
> index 913197f68caa..795c013c1c2a 100644
> --- a/tc/q_taprio.c
> +++ b/tc/q_taprio.c
> @@ -416,14 +416,11 @@ static int taprio_parse_opt(struct qdisc_util *qu, int argc,
>  	return 0;
>  }
>  
> -static int print_sched_list(FILE *f, struct rtattr *list)
> +static void print_sched_list(FILE *f, struct rtattr *list)
>  {
> -	struct rtattr *item;
> +	struct rtattr *item, *nla;
>  	int rem;
>  
> -	if (list == NULL)
> -		return 0;
> -
>  	rem = RTA_PAYLOAD(list);
>  
>  	open_json_array(PRINT_JSON, "schedule");
> @@ -432,60 +429,78 @@ static int print_sched_list(FILE *f, struct rtattr *list)
>  
>  	for (item = RTA_DATA(list); RTA_OK(item, rem); item = RTA_NEXT(item, rem)) {
>  		struct rtattr *tb[TCA_TAPRIO_SCHED_ENTRY_MAX + 1];
> -		__u32 index = 0, gatemask = 0, interval = 0;
> -		__u8 command = 0;
> +		__u32 index, gatemask, interval;
> +		__u8 command;

nitpick, optional: as you are already opening blocks for each of the
fields, you could move these declarations there. (same comment for the
next patch)

For the series:

Acked-by: Vinicius Costa Gomes <[email-masked]>

Cheers,
-- 
Vinicius