From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v2] net_sched: sch_sfq: fix allot handling
Date: Wed, 15 Dec 2010 17:55:20 +0100
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Cc: David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Jarek Poplawski <jarkao2@gmail.com>
To: Patrick McHardy <kaber@trash.net>
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Le mercredi 15 d=C3=A9cembre 2010 =C3=A0 17:43 +0100, Patrick McHardy a=
 =C3=A9crit :

> Now we could remove the allot increase in sfq_dequeue for
> the case that the flow becomes inactive. It is incorrect
> anyways.

Hmm, we increase the allot for the next slot, not for the slot now
empty.


        /* Is the slot empty? */
        if (q->qs[a].qlen =3D=3D 0) {
                q->ht[q->hash[a]] =3D SFQ_DEPTH;
                a =3D q->next[a]; // a =3D next slot index
                if (a =3D=3D old_a) {
                        q->tail =3D SFQ_DEPTH;
                        return skb;
                }
                q->next[q->tail] =3D a;
                q->allot[a] +=3D q->quantum;
// HERE, q->allot[a] is for next slot, we give it its quantum for being
activated

        } else if ((q->allot[a] -=3D qdisc_pkt_len(skb)) <=3D 0) {

Maybe we should rename (a / old_a) by (a / next_a) to avoid confusion :=
)

I was thinking in allowing more packets per SFQ (but keep the 126 activ=
e
flows limit), what do you think ?