From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC PATCH 08/13] net: sched: support skb_bad_tx with lockless
 qdisc
Date: Wed, 17 Aug 2016 15:58:06 -0700
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To: John Fastabend <john.fastabend@gmail.com>
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On Wed, 2016-08-17 at 12:36 -0700, John Fastabend wrote:
> Similar to how gso is handled skb_bad_tx needs to be per cpu to handle
> lockless qdisc with multiple writer/producers.
\
> @@ -1021,6 +1026,7 @@ err_out4:
>  	free_percpu(sch->cpu_bstats);
>  	free_percpu(sch->cpu_qstats);
>  	free_percpu(sch->gso_cpu_skb);
> +	free_percpu(sch->skb_bad_txq_cpu);


This might be the time to group all these per cpu allocations to a
single one, to help data locality and decrease overhead of having XX
pointers.