From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [net-next PATCH 04/15] net: sched: provide per cpu qstat helpers
Date: Tue, 23 Aug 2016 16:25:13 -0700
Message-ID: <1471994713.14381.63.camel@edumazet-glaptop3.roam.corp.google.com>
References: <20160823202135.14368.62466.stgit@john-Precision-Tower-5810>
         <20160823202412.14368.48361.stgit@john-Precision-Tower-5810>
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Cc: jhs@mojatatu.com, davem@davemloft.net, brouer@redhat.com,
        xiyou.wangcong@gmail.com, alexei.starovoitov@gmail.com,
        john.r.fastabend@intel.com, netdev@vger.kernel.org
To: John Fastabend <john.fastabend@gmail.com>
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On Tue, 2016-08-23 at 13:24 -0700, John Fastabend wrote:
> The per cpu qstats support was added with per cpu bstat support which
> is currently used by the ingress qdisc. This patch adds a set of
> helpers needed to make other qdiscs that use qstats per cpu as well.
> 
> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
> ---
>  include/net/sch_generic.h |   39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
> index 3de6a8c..f1b8268 100644
> --- a/include/net/sch_generic.h
> +++ b/include/net/sch_generic.h
> @@ -565,12 +565,43 @@ static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
>  	sch->qstats.backlog -= qdisc_pkt_len(skb);
>  }
>  
> +static inline void qdisc_qstats_cpu_backlog_dec(struct Qdisc *sch,
> +						const struct sk_buff *skb)
> +{
> +	struct gnet_stats_queue *q = this_cpu_ptr(sch->cpu_qstats);
> +
> +	q->backlog -= qdisc_pkt_len(skb);

Probably could use 
	this_cpu_sub(sch->cpu_qstats->backlog, qdisc_pkt_len(skb))


> +}
> +
>  static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
>  					    const struct sk_buff *skb)
>  {
>  	sch->qstats.backlog += qdisc_pkt_len(skb);
>  }
>  
> +static inline void qdisc_qstats_cpu_backlog_inc(struct Qdisc *sch,
> +						const struct sk_buff *skb)
> +{
> +	struct gnet_stats_queue *q = this_cpu_ptr(sch->cpu_qstats);
> +
> +	q->backlog += qdisc_pkt_len(skb);

	this_cpu_add(...)

> +}
> +
> +static inline void qdisc_qstats_cpu_qlen_inc(struct Qdisc *sch)
> +{
> +	this_cpu_ptr(sch->cpu_qstats)->qlen++;

	this_cpu_inc(...)
> +}
> +
> +static inline void qdisc_qstats_cpu_qlen_dec(struct Qdisc *sch)
> +{
> +	this_cpu_ptr(sch->cpu_qstats)->qlen--;

	this_cpu_dec(...)
> +}
> +
> +static inline void qdisc_qstats_cpu_requeues_inc(struct Qdisc *sch)
> +{
> +	this_cpu_ptr(sch->cpu_qstats)->requeues++;

	this_cpu_inc(...)
> +}
> +