On Wed, Jan 18, 2017 at 1:04 PM, Andrew Collins
<acoll...@cradlepoint.com> wrote:
> The fq_codel qdisc currently always regenerates the skb flow hash.
> This wastes some cycles and prevents flow seperation in cases where
> the traffic has been encrypted and can no longer be understood by the
> flow dissector.
>
> Change it to use the prexisting flow hash if one exists, and only
> regenerate if necessary.
>
> Signed-off-by: Andrew Collins <acoll...@cradlepoint.com>
> ---
> net/sched/sch_fq_codel.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
> index a5ea0e9..2f50e4c 100644
> --- a/net/sched/sch_fq_codel.c
> +++ b/net/sched/sch_fq_codel.c
> @@ -57,7 +57,6 @@ struct fq_codel_sched_data {
> struct fq_codel_flow *flows; /* Flows table [flows_cnt] */
> u32 *backlogs; /* backlog table [flows_cnt] */
> u32 flows_cnt; /* number of flows */
> - u32 perturbation; /* hash perturbation */
> u32 quantum; /* psched_mtu(qdisc_dev(sch)); */
> u32 drop_batch_size;
> u32 memory_limit;
> @@ -75,9 +74,7 @@ struct fq_codel_sched_data {
> static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
> struct sk_buff *skb)
> {
> - u32 hash = skb_get_hash_perturb(skb, q->perturbation);
> -
> - return reciprocal_scale(hash, q->flows_cnt);
> + return reciprocal_scale(skb_get_hash(skb), q->flows_cnt);
So the perturbing of the hash is no longer needed for fq_codel?
> }
>
> static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
> @@ -482,7 +479,6 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr
> *opt)
> q->memory_limit = 32 << 20; /* 32 MBytes */
> q->drop_batch_size = 64;
> q->quantum = psched_mtu(qdisc_dev(sch));
> - q->perturbation = prandom_u32();
> INIT_LIST_HEAD(&q->new_flows);
> INIT_LIST_HEAD(&q->old_flows);
> codel_params_init(&q->cparams);
> --
> 2.9.3
>
