From: Baowen Zheng <baowen.zh...@corigine.com>
Allow a policer action to enforce a rate-limit based on packets-per-second,
configurable using a packet-per-second rate and burst parameters. This may
be used in conjunction with existing byte-per-second rate limiting in the
same policer action.
e.g.
tc filter add dev tap1 parent ffff: u32 match \
u32 0 0 police pkts_rate 3000 pkts_burst 1000
Testing was unable to uncover a performance impact of this change on
existing features.
Signed-off-by: Baowen Zheng <baowen.zh...@corigine.com>
Signed-off-by: Simon Horman <simon.hor...@netronome.com>
Signed-off-by: Louis Peens <louis.pe...@netronome.com>
---
include/net/sch_generic.h | 15 ++++++++++++++
include/net/tc_act/tc_police.h | 4 ++++
include/uapi/linux/pkt_cls.h | 2 ++
net/sched/act_police.c | 37 +++++++++++++++++++++++++++++++---
net/sched/sch_generic.c | 32 +++++++++++++++++++++++++++++
5 files changed, 87 insertions(+), 3 deletions(-)
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 639e465a108f..1a93ad634fee 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -1234,6 +1234,21 @@ static inline void psched_ratecfg_getrate(struct
tc_ratespec *res,
res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
}
+struct psched_pktrate {
+ u64 rate_pkts_ps; /* packets per second */
+ u32 mult;
+ u8 shift;
+};
+
+static inline u64 psched_pkt2t_ns(const struct psched_pktrate *r,
+ unsigned int pkt_num)
+{
+ return ((u64)pkt_num * r->mult) >> r->shift;
+}
+
+void psched_ppscfg_precompute(struct psched_pktrate *r,
+ u64 pktrate64);
+
/* Mini Qdisc serves for specific needs of ingress/clsact Qdisc.
* The fast path only needs to access filter list and to update stats
*/
diff --git a/include/net/tc_act/tc_police.h b/include/net/tc_act/tc_police.h
index 6d1e26b709b5..b106460a8d66 100644
--- a/include/net/tc_act/tc_police.h
+++ b/include/net/tc_act/tc_police.h
@@ -10,10 +10,13 @@ struct tcf_police_params {
s64 tcfp_burst;
u32 tcfp_mtu;
s64 tcfp_mtu_ptoks;
+ s64 tcfp_pkt_burst;
struct psched_ratecfg rate;
bool rate_present;
struct psched_ratecfg peak;
bool peak_present;
+ struct psched_pktrate ppsrate;
+ bool pps_present;
struct rcu_head rcu;
};
@@ -24,6 +27,7 @@ struct tcf_police {
spinlock_t tcfp_lock ____cacheline_aligned_in_smp;
s64 tcfp_toks;
s64 tcfp_ptoks;
+ s64 tcfp_pkttoks;
s64 tcfp_t_c;
};
diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index ee95f42fb0ec..bffa54e73785 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -190,6 +190,8 @@ enum {
TCA_POLICE_PAD,
TCA_POLICE_RATE64,
TCA_POLICE_PEAKRATE64,
+ TCA_POLICE_PKTRATE64,
+ TCA_POLICE_PKTBURST64,
__TCA_POLICE_MAX
#define TCA_POLICE_RESULT TCA_POLICE_RESULT
};
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 8d8452b1cdd4..d700b2105535 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -42,6 +42,8 @@ static const struct nla_policy police_policy[TCA_POLICE_MAX +
1] = {
[TCA_POLICE_RESULT] = { .type = NLA_U32 },
[TCA_POLICE_RATE64] = { .type = NLA_U64 },
[TCA_POLICE_PEAKRATE64] = { .type = NLA_U64 },
+ [TCA_POLICE_PKTRATE64] = { .type = NLA_U64 },
+ [TCA_POLICE_PKTBURST64] = { .type = NLA_U64 },
};
static int tcf_police_init(struct net *net, struct nlattr *nla,
@@ -61,6 +63,7 @@ static int tcf_police_init(struct net *net, struct nlattr
*nla,
bool exists = false;
u32 index;
u64 rate64, prate64;
+ u64 pps, ppsburst;
if (nla == NULL)
return -EINVAL;
@@ -183,6 +186,16 @@ static int tcf_police_init(struct net *net, struct nlattr
*nla,
if (tb[TCA_POLICE_AVRATE])
new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
+ if (tb[TCA_POLICE_PKTRATE64] && tb[TCA_POLICE_PKTBURST64]) {
+ pps = nla_get_u64(tb[TCA_POLICE_PKTRATE64]);
+ ppsburst = nla_get_u64(tb[TCA_POLICE_PKTBURST64]);
+ if (pps) {
+ new->pps_present = true;
+ new->tcfp_pkt_burst = PSCHED_TICKS2NS(ppsburst);
+ psched_ppscfg_precompute(&new->ppsrate, pps);
+ }
+ }
+
spin_lock_bh(&police->tcf_lock);
spin_lock_bh(&police->tcfp_lock);
police->tcfp_t_c = ktime_get_ns();
@@ -217,8 +230,8 @@ static int tcf_police_act(struct sk_buff *skb, const struct
tc_action *a,
struct tcf_result *res)
{
struct tcf_police *police = to_police(a);
+ s64 now, toks, ppstoks = 0, ptoks = 0;
struct tcf_police_params *p;
- s64 now, toks, ptoks = 0;
int ret;
tcf_lastuse_update(&police->tcf_tm);
@@ -236,7 +249,7 @@ static int tcf_police_act(struct sk_buff *skb, const struct
tc_action *a,
}
if (qdisc_pkt_len(skb) <= p->tcfp_mtu) {
- if (!p->rate_present) {
+ if (!p->rate_present && !p->pps_present) {
ret = p->tcfp_result;
goto end;
}
@@ -251,14 +264,22 @@ static int tcf_police_act(struct sk_buff *skb, const
struct tc_action *a,
ptoks -= (s64)psched_l2t_ns(&p->peak,
qdisc_pkt_len(skb));
}
+ if (p->pps_present) {
+ ppstoks = min_t(s64, now - police->tcfp_t_c,
p->tcfp_pkt_burst);
+ ppstoks += police->tcfp_pkttoks;
+ if (ppstoks > p->tcfp_pkt_burst)
+ ppstoks = p->tcfp_pkt_burst;
+ ppstoks -= (s64)psched_pkt2t_ns(&p->ppsrate, 1);
+ }
toks += police->tcfp_toks;
if (toks > p->tcfp_burst)
toks = p->tcfp_burst;
toks -= (s64)psched_l2t_ns(&p->rate, qdisc_pkt_len(skb));
- if ((toks|ptoks) >= 0) {
+ if ((toks | ptoks | ppstoks) >= 0) {
police->tcfp_t_c = now;
police->tcfp_toks = toks;
police->tcfp_ptoks = ptoks;
+ police->tcfp_pkttoks = ppstoks;
spin_unlock_bh(&police->tcfp_lock);
ret = p->tcfp_result;
goto inc_drops;
@@ -331,6 +352,16 @@ static int tcf_police_dump(struct sk_buff *skb, struct
tc_action *a,
TCA_POLICE_PAD))
goto nla_put_failure;
}
+ if (p->pps_present) {
+ if (nla_put_u64_64bit(skb, TCA_POLICE_PKTRATE64,
+ police->params->ppsrate.rate_pkts_ps,
+ TCA_POLICE_PAD))
+ goto nla_put_failure;
+ if (nla_put_u64_64bit(skb, TCA_POLICE_PKTBURST64,
+ PSCHED_NS2TICKS(p->tcfp_pkt_burst),
+ TCA_POLICE_PAD))
+ goto nla_put_failure;
+ }
if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
goto nla_put_failure;
if (p->tcfp_result &&
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 49eae93d1489..209e34ee4bd3 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -1361,6 +1361,38 @@ void psched_ratecfg_precompute(struct psched_ratecfg *r,
}
EXPORT_SYMBOL(psched_ratecfg_precompute);
+void psched_ppscfg_precompute(struct psched_pktrate *r,
+ u64 pktrate64)
+{
+ memset(r, 0, sizeof(*r));
+ r->rate_pkts_ps = pktrate64;
+ r->mult = 1;
+ /* The deal here is to replace a divide by a reciprocal one
+ * in fast path (a reciprocal divide is a multiply and a shift)
+ *
+ * Normal formula would be :
+ * time_in_ns = (NSEC_PER_SEC * pkt_num) / pktrate64
+ *
+ * We compute mult/shift to use instead :
+ * time_in_ns = (len * mult) >> shift;
+ *
+ * We try to get the highest possible mult value for accuracy,
+ * but have to make sure no overflows will ever happen.
+ */
+ if (r->rate_pkts_ps > 0) {
+ u64 factor = NSEC_PER_SEC;
+
+ for (;;) {
+ r->mult = div64_u64(factor, r->rate_pkts_ps);
+ if (r->mult & (1U << 31) || factor & (1ULL << 63))
+ break;
+ factor <<= 1;
+ r->shift++;
+ }
+ }
+}
+EXPORT_SYMBOL(psched_ppscfg_precompute);
+
static void mini_qdisc_rcu_func(struct rcu_head *head)
{
}
--
2.20.1
