From 264b87fa617e758966108db48db220571ff3d60e Mon Sep 17 00:00:00 2001 From: Andrew Collins Date: Wed, 18 Jan 2017 14:04:28 -0700 Subject: [PATCH] fq_codel: Avoid regenerating skb flow hash unless necessary 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 Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- 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 a5ea0e9b6be4..2f50e4c72fb4 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); } 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);