Subject: Re: [PATCH net-next 6/6] net_sched: act: remove spinlock in fast path

From: Jamal Hadi Salim <[email-masked]>
Date: Fri, 03 Jul 2015 07:07:27 -0400

On 07/02/15 09:07, Eric Dumazet wrote:
> Final step for gact RCU operation :
>
> 1) Use percpu stats
> 2) update lastuse only every clock tick
> 3) Remove spinlock acquisition, as it is no longer needed.
>
> Since this is the last contended lock in packet RX when tc gact is used,
> this gives impressive gain.
>
> My host with 8 RX queues was handling 5 Mpps before the patch,
> and more than 10 Mpps after patch.
>
> Tested:
>
> On receiver :
> IP=ip
> TC=tc
> dev=eth0
>
> $TC qdisc del dev $dev ingress 2>/dev/null
> $TC qdisc add dev $dev ingress
> $TC filter del dev $dev root pref 10 2>/dev/null
> $TC filter del dev $dev pref 10 2>/dev/null
> tc filter add dev $dev est 1sec 4sec parent ffff: protocol ip prio 1 \
> 	u32 match ip src 7.0.0.0/8 flowid 1:15 action drop
>
> Sender sends packets flood from 7/8 network
>

Very nice Eric;-> thanks.
So now basic accept/drop should be flying ;->
Other really low hanging fruit is act_csum, vlan and skbedit.
CCing the respective authors.

> Signed-off-by: Eric Dumazet <[email-masked]>
> Cc: Alexei Starovoitov <[email-masked]>
> Cc: Jamal Hadi Salim <[email-masked]>

Acked-by: Jamal Hadi Salim <[email-masked]>

cheers,
jamal