Subject: Re: [PATCH net-next v11 4/4] net sched actions: add time filter for action dumping

From: Jiri Pirko <[email-masked]>
Date: Mon, 24 Jul 2017 13:34:50 +0200

Mon, Jul 24, 2017 at 03:35:46AM CEST, [email-masked] wrote:
>From: Jamal Hadi Salim <[email-masked]>
>
>This patch adds support for filtering based on time since last used.
>When we are dumping a large number of actions it is useful to
>have the option of filtering based on when the action was last
>used to reduce the amount of data crossing to user space.
>
>With this patch the user space app sets the TCA_ROOT_TIME_DELTA
>attribute with the value in milliseconds with "time of interest
>since now".  The kernel converts this to jiffies and does the
>filtering comparison matching entries that have seen activity
>since then and returns them to user space.
>Old kernels and old tc continue to work in legacy mode since
>they dont specify this attribute.

[...]

>@@ -128,6 +129,11 @@ static int tcf_dump_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
> 			if (index < s_i)
> 				continue;
> 
>+			if (jiffy_since &&
>+			    time_after(jiffy_since,
>+				       (unsigned long)p->tcfa_tm.lastuse))

You don't need to check jiffy_since==0. Also, nicer  ^^ this with a space :)

Other than this, looks fine. Thanks.