forked from mirrors/linux
fq_codel: Fair Queue Codel AQM
Fair Queue Codel packet scheduler
Principles :
- Packets are classified (internal classifier or external) on flows.
- This is a Stochastic model (as we use a hash, several flows might
be hashed on same slot)
- Each flow has a CoDel managed queue.
- Flows are linked onto two (Round Robin) lists,
so that new flows have priority on old ones.
- For a given flow, packets are not reordered (CoDel uses a FIFO)
- head drops only.
- ECN capability is on by default.
- Very low memory footprint (64 bytes per flow)
tc qdisc ... fq_codel [ limit PACKETS ] [ flows number ]
[ target TIME ] [ interval TIME ] [ noecn ]
[ quantum BYTES ]
defaults : 1024 flows, 10240 packets limit, quantum : device MTU
target : 5ms (CoDel default)
interval : 100ms (CoDel default)
Impressive results on load :
class htb 1:1 root leaf 10: prio 0 quantum 1514 rate 200000Kbit ceil 200000Kbit burst 1475b/8 mpu 0b overhead 0b cburst 1475b/8 mpu 0b overhead 0b level 0
Sent 43304920109 bytes 33063109 pkt (dropped 0, overlimits 0 requeues 0)
rate 201691Kbit 28595pps backlog 0b 312p requeues 0
lended: 33063109 borrowed: 0 giants: 0
tokens: -912 ctokens: -912
class fq_codel 10:1735 parent 10:
(dropped 1292, overlimits 0 requeues 0)
backlog 15140b 10p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:4524 parent 10:
(dropped 1291, overlimits 0 requeues 0)
backlog 16654b 11p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:4e74 parent 10:
(dropped 1290, overlimits 0 requeues 0)
backlog 6056b 4p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 6.4ms dropping drop_next 92.0ms
class fq_codel 10:628a parent 10:
(dropped 1289, overlimits 0 requeues 0)
backlog 7570b 5p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 5.4ms dropping drop_next 90.9ms
class fq_codel 10:a4b3 parent 10:
(dropped 302, overlimits 0 requeues 0)
backlog 16654b 11p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:c3c2 parent 10:
(dropped 1284, overlimits 0 requeues 0)
backlog 13626b 9p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 5.9ms
class fq_codel 10:d331 parent 10:
(dropped 299, overlimits 0 requeues 0)
backlog 15140b 10p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.0ms
class fq_codel 10:d526 parent 10:
(dropped 12160, overlimits 0 requeues 0)
backlog 35870b 211p requeues 0
deficit 1508 count 12160 lastcount 1 ldelay 15.3ms dropping drop_next 247us
class fq_codel 10:e2c6 parent 10:
(dropped 1288, overlimits 0 requeues 0)
backlog 15140b 10p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:eab5 parent 10:
(dropped 1285, overlimits 0 requeues 0)
backlog 16654b 11p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 5.9ms
class fq_codel 10:f220 parent 10:
(dropped 1289, overlimits 0 requeues 0)
backlog 15140b 10p requeues 0
deficit 1514 count 1 lastcount 1 ldelay 7.1ms
qdisc htb 1: root refcnt 6 r2q 10 default 1 direct_packets_stat 0 ver 3.17
Sent 43331086547 bytes 33092812 pkt (dropped 0, overlimits 66063544 requeues 71)
rate 201697Kbit 28602pps backlog 0b 260p requeues 71
qdisc fq_codel 10: parent 1:1 limit 10240p flows 65536 target 5.0ms interval 100.0ms ecn
Sent 43331086547 bytes 33092812 pkt (dropped 949359, overlimits 0 requeues 0)
rate 201697Kbit 28602pps backlog 189352b 260p requeues 0
maxpacket 1514 drop_overlimit 0 new_flow_count 5582 ecn_mark 125593
new_flows_len 0 old_flows_len 11
PING 172.30.42.18 (172.30.42.18) 56(84) bytes of data.
64 bytes from 172.30.42.18: icmp_req=1 ttl=64 time=0.227 ms
64 bytes from 172.30.42.18: icmp_req=2 ttl=64 time=0.165 ms
64 bytes from 172.30.42.18: icmp_req=3 ttl=64 time=0.166 ms
64 bytes from 172.30.42.18: icmp_req=4 ttl=64 time=0.151 ms
64 bytes from 172.30.42.18: icmp_req=5 ttl=64 time=0.164 ms
64 bytes from 172.30.42.18: icmp_req=6 ttl=64 time=0.172 ms
64 bytes from 172.30.42.18: icmp_req=7 ttl=64 time=0.175 ms
64 bytes from 172.30.42.18: icmp_req=8 ttl=64 time=0.183 ms
64 bytes from 172.30.42.18: icmp_req=9 ttl=64 time=0.158 ms
64 bytes from 172.30.42.18: icmp_req=10 ttl=64 time=0.200 ms
10 packets transmitted, 10 received, 0% packet loss, time 8999ms
rtt min/avg/max/mdev = 0.151/0.176/0.227/0.022 ms
Much better than SFQ because of priority given to new flows, and fast
path dirtying less cache lines.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
David S. Miller
parent
536edd6710
commit
4b549a2ef4
4 changed files with 690 additions and 0 deletions
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@ -681,4 +681,58 @@ struct tc_codel_xstats {
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__u32 dropping; /* are we in dropping state ? */
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__u32 dropping; /* are we in dropping state ? */
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};
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};
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/* FQ_CODEL */
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enum {
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TCA_FQ_CODEL_UNSPEC,
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TCA_FQ_CODEL_TARGET,
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TCA_FQ_CODEL_LIMIT,
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TCA_FQ_CODEL_INTERVAL,
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TCA_FQ_CODEL_ECN,
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TCA_FQ_CODEL_FLOWS,
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TCA_FQ_CODEL_QUANTUM,
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__TCA_FQ_CODEL_MAX
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};
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#define TCA_FQ_CODEL_MAX (__TCA_FQ_CODEL_MAX - 1)
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enum {
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TCA_FQ_CODEL_XSTATS_QDISC,
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TCA_FQ_CODEL_XSTATS_CLASS,
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};
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struct tc_fq_codel_qd_stats {
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__u32 maxpacket; /* largest packet we've seen so far */
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__u32 drop_overlimit; /* number of time max qdisc
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* packet limit was hit
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*/
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__u32 ecn_mark; /* number of packets we ECN marked
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* instead of being dropped
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*/
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__u32 new_flow_count; /* number of time packets
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* created a 'new flow'
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*/
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__u32 new_flows_len; /* count of flows in new list */
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__u32 old_flows_len; /* count of flows in old list */
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};
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struct tc_fq_codel_cl_stats {
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__s32 deficit;
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__u32 ldelay; /* in-queue delay seen by most recently
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* dequeued packet
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*/
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__u32 count;
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__u32 lastcount;
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__u32 dropping;
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__s32 drop_next;
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};
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struct tc_fq_codel_xstats {
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__u32 type;
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union {
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struct tc_fq_codel_qd_stats qdisc_stats;
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struct tc_fq_codel_cl_stats class_stats;
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};
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};
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#endif
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#endif
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@ -261,6 +261,17 @@ config NET_SCH_CODEL
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If unsure, say N.
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If unsure, say N.
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config NET_SCH_FQ_CODEL
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tristate "Fair Queue Controlled Delay AQM (FQ_CODEL)"
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help
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Say Y here if you want to use the FQ Controlled Delay (FQ_CODEL)
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packet scheduling algorithm.
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To compile this driver as a module, choose M here: the module
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will be called sch_fq_codel.
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If unsure, say N.
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config NET_SCH_INGRESS
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config NET_SCH_INGRESS
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tristate "Ingress Qdisc"
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tristate "Ingress Qdisc"
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depends on NET_CLS_ACT
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depends on NET_CLS_ACT
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@ -38,6 +38,7 @@ obj-$(CONFIG_NET_SCH_MQPRIO) += sch_mqprio.o
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obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o
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obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o
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obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o
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obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o
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obj-$(CONFIG_NET_SCH_CODEL) += sch_codel.o
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obj-$(CONFIG_NET_SCH_CODEL) += sch_codel.o
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obj-$(CONFIG_NET_SCH_FQ_CODEL) += sch_fq_codel.o
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obj-$(CONFIG_NET_CLS_U32) += cls_u32.o
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obj-$(CONFIG_NET_CLS_U32) += cls_u32.o
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obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o
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obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o
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624
net/sched/sch_fq_codel.c
Normal file
624
net/sched/sch_fq_codel.c
Normal file
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@ -0,0 +1,624 @@
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/*
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* Fair Queue CoDel discipline
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/jiffies.h>
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#include <linux/string.h>
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#include <linux/in.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/skbuff.h>
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#include <linux/jhash.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <net/netlink.h>
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#include <net/pkt_sched.h>
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#include <net/flow_keys.h>
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#include <net/codel.h>
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/* Fair Queue CoDel.
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*
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* Principles :
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* Packets are classified (internal classifier or external) on flows.
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* This is a Stochastic model (as we use a hash, several flows
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* might be hashed on same slot)
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* Each flow has a CoDel managed queue.
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* Flows are linked onto two (Round Robin) lists,
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* so that new flows have priority on old ones.
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*
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* For a given flow, packets are not reordered (CoDel uses a FIFO)
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* head drops only.
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* ECN capability is on by default.
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* Low memory footprint (64 bytes per flow)
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*/
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struct fq_codel_flow {
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struct sk_buff *head;
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struct sk_buff *tail;
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struct list_head flowchain;
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int deficit;
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u32 dropped; /* number of drops (or ECN marks) on this flow */
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struct codel_vars cvars;
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}; /* please try to keep this structure <= 64 bytes */
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struct fq_codel_sched_data {
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struct tcf_proto *filter_list; /* optional external classifier */
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struct fq_codel_flow *flows; /* Flows table [flows_cnt] */
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u32 *backlogs; /* backlog table [flows_cnt] */
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u32 flows_cnt; /* number of flows */
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u32 perturbation; /* hash perturbation */
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u32 quantum; /* psched_mtu(qdisc_dev(sch)); */
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struct codel_params cparams;
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struct codel_stats cstats;
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u32 drop_overlimit;
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u32 new_flow_count;
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struct list_head new_flows; /* list of new flows */
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struct list_head old_flows; /* list of old flows */
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};
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static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
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const struct sk_buff *skb)
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{
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struct flow_keys keys;
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unsigned int hash;
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skb_flow_dissect(skb, &keys);
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hash = jhash_3words((__force u32)keys.dst,
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(__force u32)keys.src ^ keys.ip_proto,
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(__force u32)keys.ports, q->perturbation);
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return ((u64)hash * q->flows_cnt) >> 32;
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}
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static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
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int *qerr)
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{
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struct fq_codel_sched_data *q = qdisc_priv(sch);
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struct tcf_result res;
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int result;
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if (TC_H_MAJ(skb->priority) == sch->handle &&
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TC_H_MIN(skb->priority) > 0 &&
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TC_H_MIN(skb->priority) <= q->flows_cnt)
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return TC_H_MIN(skb->priority);
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if (!q->filter_list)
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return fq_codel_hash(q, skb) + 1;
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*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
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result = tc_classify(skb, q->filter_list, &res);
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if (result >= 0) {
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#ifdef CONFIG_NET_CLS_ACT
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switch (result) {
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case TC_ACT_STOLEN:
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case TC_ACT_QUEUED:
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*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
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case TC_ACT_SHOT:
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return 0;
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}
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#endif
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if (TC_H_MIN(res.classid) <= q->flows_cnt)
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return TC_H_MIN(res.classid);
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}
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return 0;
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}
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/* helper functions : might be changed when/if skb use a standard list_head */
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/* remove one skb from head of slot queue */
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static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)
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{
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struct sk_buff *skb = flow->head;
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flow->head = skb->next;
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skb->next = NULL;
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return skb;
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}
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/* add skb to flow queue (tail add) */
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static inline void flow_queue_add(struct fq_codel_flow *flow,
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struct sk_buff *skb)
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{
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if (flow->head == NULL)
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flow->head = skb;
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else
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flow->tail->next = skb;
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flow->tail = skb;
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skb->next = NULL;
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}
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static unsigned int fq_codel_drop(struct Qdisc *sch)
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{
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struct fq_codel_sched_data *q = qdisc_priv(sch);
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struct sk_buff *skb;
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unsigned int maxbacklog = 0, idx = 0, i, len;
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struct fq_codel_flow *flow;
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/* Queue is full! Find the fat flow and drop packet from it.
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* This might sound expensive, but with 1024 flows, we scan
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* 4KB of memory, and we dont need to handle a complex tree
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* in fast path (packet queue/enqueue) with many cache misses.
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*/
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for (i = 0; i < q->flows_cnt; i++) {
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if (q->backlogs[i] > maxbacklog) {
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maxbacklog = q->backlogs[i];
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idx = i;
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}
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}
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flow = &q->flows[idx];
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skb = dequeue_head(flow);
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len = qdisc_pkt_len(skb);
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q->backlogs[idx] -= len;
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kfree_skb(skb);
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sch->q.qlen--;
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sch->qstats.drops++;
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sch->qstats.backlog -= len;
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flow->dropped++;
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return idx;
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}
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static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch)
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{
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struct fq_codel_sched_data *q = qdisc_priv(sch);
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unsigned int idx;
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struct fq_codel_flow *flow;
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int uninitialized_var(ret);
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idx = fq_codel_classify(skb, sch, &ret);
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if (idx == 0) {
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if (ret & __NET_XMIT_BYPASS)
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sch->qstats.drops++;
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kfree_skb(skb);
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return ret;
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}
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idx--;
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codel_set_enqueue_time(skb);
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flow = &q->flows[idx];
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flow_queue_add(flow, skb);
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q->backlogs[idx] += qdisc_pkt_len(skb);
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sch->qstats.backlog += qdisc_pkt_len(skb);
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if (list_empty(&flow->flowchain)) {
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list_add_tail(&flow->flowchain, &q->new_flows);
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codel_vars_init(&flow->cvars);
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q->new_flow_count++;
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flow->deficit = q->quantum;
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flow->dropped = 0;
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}
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if (++sch->q.qlen < sch->limit)
|
||||||
|
return NET_XMIT_SUCCESS;
|
||||||
|
|
||||||
|
q->drop_overlimit++;
|
||||||
|
/* Return Congestion Notification only if we dropped a packet
|
||||||
|
* from this flow.
|
||||||
|
*/
|
||||||
|
if (fq_codel_drop(sch) == idx)
|
||||||
|
return NET_XMIT_CN;
|
||||||
|
|
||||||
|
/* As we dropped a packet, better let upper stack know this */
|
||||||
|
qdisc_tree_decrease_qlen(sch, 1);
|
||||||
|
return NET_XMIT_SUCCESS;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* This is the specific function called from codel_dequeue()
|
||||||
|
* to dequeue a packet from queue. Note: backlog is handled in
|
||||||
|
* codel, we dont need to reduce it here.
|
||||||
|
*/
|
||||||
|
static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch)
|
||||||
|
{
|
||||||
|
struct fq_codel_flow *flow;
|
||||||
|
struct sk_buff *skb = NULL;
|
||||||
|
|
||||||
|
flow = container_of(vars, struct fq_codel_flow, cvars);
|
||||||
|
if (flow->head) {
|
||||||
|
skb = dequeue_head(flow);
|
||||||
|
sch->qstats.backlog -= qdisc_pkt_len(skb);
|
||||||
|
sch->q.qlen--;
|
||||||
|
}
|
||||||
|
return skb;
|
||||||
|
}
|
||||||
|
|
||||||
|
static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
struct sk_buff *skb;
|
||||||
|
struct fq_codel_flow *flow;
|
||||||
|
struct list_head *head;
|
||||||
|
u32 prev_drop_count, prev_ecn_mark;
|
||||||
|
|
||||||
|
begin:
|
||||||
|
head = &q->new_flows;
|
||||||
|
if (list_empty(head)) {
|
||||||
|
head = &q->old_flows;
|
||||||
|
if (list_empty(head))
|
||||||
|
return NULL;
|
||||||
|
}
|
||||||
|
flow = list_first_entry(head, struct fq_codel_flow, flowchain);
|
||||||
|
|
||||||
|
if (flow->deficit <= 0) {
|
||||||
|
flow->deficit += q->quantum;
|
||||||
|
list_move_tail(&flow->flowchain, &q->old_flows);
|
||||||
|
goto begin;
|
||||||
|
}
|
||||||
|
|
||||||
|
prev_drop_count = q->cstats.drop_count;
|
||||||
|
prev_ecn_mark = q->cstats.ecn_mark;
|
||||||
|
|
||||||
|
skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats,
|
||||||
|
dequeue, &q->backlogs[flow - q->flows]);
|
||||||
|
|
||||||
|
flow->dropped += q->cstats.drop_count - prev_drop_count;
|
||||||
|
flow->dropped += q->cstats.ecn_mark - prev_ecn_mark;
|
||||||
|
|
||||||
|
if (!skb) {
|
||||||
|
/* force a pass through old_flows to prevent starvation */
|
||||||
|
if ((head == &q->new_flows) && !list_empty(&q->old_flows))
|
||||||
|
list_move_tail(&flow->flowchain, &q->old_flows);
|
||||||
|
else
|
||||||
|
list_del_init(&flow->flowchain);
|
||||||
|
goto begin;
|
||||||
|
}
|
||||||
|
qdisc_bstats_update(sch, skb);
|
||||||
|
flow->deficit -= qdisc_pkt_len(skb);
|
||||||
|
/* We cant call qdisc_tree_decrease_qlen() if our qlen is 0,
|
||||||
|
* or HTB crashes. Defer it for next round.
|
||||||
|
*/
|
||||||
|
if (q->cstats.drop_count && sch->q.qlen) {
|
||||||
|
qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
|
||||||
|
q->cstats.drop_count = 0;
|
||||||
|
}
|
||||||
|
return skb;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void fq_codel_reset(struct Qdisc *sch)
|
||||||
|
{
|
||||||
|
struct sk_buff *skb;
|
||||||
|
|
||||||
|
while ((skb = fq_codel_dequeue(sch)) != NULL)
|
||||||
|
kfree_skb(skb);
|
||||||
|
}
|
||||||
|
|
||||||
|
static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = {
|
||||||
|
[TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 },
|
||||||
|
[TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 },
|
||||||
|
[TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 },
|
||||||
|
[TCA_FQ_CODEL_ECN] = { .type = NLA_U32 },
|
||||||
|
[TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 },
|
||||||
|
[TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 },
|
||||||
|
};
|
||||||
|
|
||||||
|
static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
struct nlattr *tb[TCA_FQ_CODEL_MAX + 1];
|
||||||
|
int err;
|
||||||
|
|
||||||
|
if (!opt)
|
||||||
|
return -EINVAL;
|
||||||
|
|
||||||
|
err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy);
|
||||||
|
if (err < 0)
|
||||||
|
return err;
|
||||||
|
if (tb[TCA_FQ_CODEL_FLOWS]) {
|
||||||
|
if (q->flows)
|
||||||
|
return -EINVAL;
|
||||||
|
q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]);
|
||||||
|
if (!q->flows_cnt ||
|
||||||
|
q->flows_cnt > 65536)
|
||||||
|
return -EINVAL;
|
||||||
|
}
|
||||||
|
sch_tree_lock(sch);
|
||||||
|
|
||||||
|
if (tb[TCA_FQ_CODEL_TARGET]) {
|
||||||
|
u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]);
|
||||||
|
|
||||||
|
q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (tb[TCA_FQ_CODEL_INTERVAL]) {
|
||||||
|
u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
|
||||||
|
|
||||||
|
q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (tb[TCA_FQ_CODEL_LIMIT])
|
||||||
|
sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]);
|
||||||
|
|
||||||
|
if (tb[TCA_FQ_CODEL_ECN])
|
||||||
|
q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]);
|
||||||
|
|
||||||
|
if (tb[TCA_FQ_CODEL_QUANTUM])
|
||||||
|
q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM]));
|
||||||
|
|
||||||
|
while (sch->q.qlen > sch->limit) {
|
||||||
|
struct sk_buff *skb = fq_codel_dequeue(sch);
|
||||||
|
|
||||||
|
kfree_skb(skb);
|
||||||
|
q->cstats.drop_count++;
|
||||||
|
}
|
||||||
|
qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
|
||||||
|
q->cstats.drop_count = 0;
|
||||||
|
|
||||||
|
sch_tree_unlock(sch);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void *fq_codel_zalloc(size_t sz)
|
||||||
|
{
|
||||||
|
void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN);
|
||||||
|
|
||||||
|
if (!ptr)
|
||||||
|
ptr = vzalloc(sz);
|
||||||
|
return ptr;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void fq_codel_free(void *addr)
|
||||||
|
{
|
||||||
|
if (addr) {
|
||||||
|
if (is_vmalloc_addr(addr))
|
||||||
|
vfree(addr);
|
||||||
|
else
|
||||||
|
kfree(addr);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
static void fq_codel_destroy(struct Qdisc *sch)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
|
||||||
|
tcf_destroy_chain(&q->filter_list);
|
||||||
|
fq_codel_free(q->backlogs);
|
||||||
|
fq_codel_free(q->flows);
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
int i;
|
||||||
|
|
||||||
|
sch->limit = 10*1024;
|
||||||
|
q->flows_cnt = 1024;
|
||||||
|
q->quantum = psched_mtu(qdisc_dev(sch));
|
||||||
|
q->perturbation = net_random();
|
||||||
|
INIT_LIST_HEAD(&q->new_flows);
|
||||||
|
INIT_LIST_HEAD(&q->old_flows);
|
||||||
|
codel_params_init(&q->cparams);
|
||||||
|
codel_stats_init(&q->cstats);
|
||||||
|
q->cparams.ecn = true;
|
||||||
|
|
||||||
|
if (opt) {
|
||||||
|
int err = fq_codel_change(sch, opt);
|
||||||
|
if (err)
|
||||||
|
return err;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (!q->flows) {
|
||||||
|
q->flows = fq_codel_zalloc(q->flows_cnt *
|
||||||
|
sizeof(struct fq_codel_flow));
|
||||||
|
if (!q->flows)
|
||||||
|
return -ENOMEM;
|
||||||
|
q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32));
|
||||||
|
if (!q->backlogs) {
|
||||||
|
fq_codel_free(q->flows);
|
||||||
|
return -ENOMEM;
|
||||||
|
}
|
||||||
|
for (i = 0; i < q->flows_cnt; i++) {
|
||||||
|
struct fq_codel_flow *flow = q->flows + i;
|
||||||
|
|
||||||
|
INIT_LIST_HEAD(&flow->flowchain);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
if (sch->limit >= 1)
|
||||||
|
sch->flags |= TCQ_F_CAN_BYPASS;
|
||||||
|
else
|
||||||
|
sch->flags &= ~TCQ_F_CAN_BYPASS;
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
struct nlattr *opts;
|
||||||
|
|
||||||
|
opts = nla_nest_start(skb, TCA_OPTIONS);
|
||||||
|
if (opts == NULL)
|
||||||
|
goto nla_put_failure;
|
||||||
|
|
||||||
|
if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET,
|
||||||
|
codel_time_to_us(q->cparams.target)) ||
|
||||||
|
nla_put_u32(skb, TCA_FQ_CODEL_LIMIT,
|
||||||
|
sch->limit) ||
|
||||||
|
nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL,
|
||||||
|
codel_time_to_us(q->cparams.interval)) ||
|
||||||
|
nla_put_u32(skb, TCA_FQ_CODEL_ECN,
|
||||||
|
q->cparams.ecn) ||
|
||||||
|
nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM,
|
||||||
|
q->quantum) ||
|
||||||
|
nla_put_u32(skb, TCA_FQ_CODEL_FLOWS,
|
||||||
|
q->flows_cnt))
|
||||||
|
goto nla_put_failure;
|
||||||
|
|
||||||
|
nla_nest_end(skb, opts);
|
||||||
|
return skb->len;
|
||||||
|
|
||||||
|
nla_put_failure:
|
||||||
|
return -1;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
struct tc_fq_codel_xstats st = {
|
||||||
|
.type = TCA_FQ_CODEL_XSTATS_QDISC,
|
||||||
|
.qdisc_stats.maxpacket = q->cstats.maxpacket,
|
||||||
|
.qdisc_stats.drop_overlimit = q->drop_overlimit,
|
||||||
|
.qdisc_stats.ecn_mark = q->cstats.ecn_mark,
|
||||||
|
.qdisc_stats.new_flow_count = q->new_flow_count,
|
||||||
|
};
|
||||||
|
struct list_head *pos;
|
||||||
|
|
||||||
|
list_for_each(pos, &q->new_flows)
|
||||||
|
st.qdisc_stats.new_flows_len++;
|
||||||
|
|
||||||
|
list_for_each(pos, &q->old_flows)
|
||||||
|
st.qdisc_stats.old_flows_len++;
|
||||||
|
|
||||||
|
return gnet_stats_copy_app(d, &st, sizeof(st));
|
||||||
|
}
|
||||||
|
|
||||||
|
static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg)
|
||||||
|
{
|
||||||
|
return NULL;
|
||||||
|
}
|
||||||
|
|
||||||
|
static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid)
|
||||||
|
{
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent,
|
||||||
|
u32 classid)
|
||||||
|
{
|
||||||
|
/* we cannot bypass queue discipline anymore */
|
||||||
|
sch->flags &= ~TCQ_F_CAN_BYPASS;
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void fq_codel_put(struct Qdisc *q, unsigned long cl)
|
||||||
|
{
|
||||||
|
}
|
||||||
|
|
||||||
|
static struct tcf_proto **fq_codel_find_tcf(struct Qdisc *sch, unsigned long cl)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
|
||||||
|
if (cl)
|
||||||
|
return NULL;
|
||||||
|
return &q->filter_list;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl,
|
||||||
|
struct sk_buff *skb, struct tcmsg *tcm)
|
||||||
|
{
|
||||||
|
tcm->tcm_handle |= TC_H_MIN(cl);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl,
|
||||||
|
struct gnet_dump *d)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
u32 idx = cl - 1;
|
||||||
|
struct gnet_stats_queue qs = { 0 };
|
||||||
|
struct tc_fq_codel_xstats xstats;
|
||||||
|
|
||||||
|
if (idx < q->flows_cnt) {
|
||||||
|
const struct fq_codel_flow *flow = &q->flows[idx];
|
||||||
|
const struct sk_buff *skb = flow->head;
|
||||||
|
|
||||||
|
memset(&xstats, 0, sizeof(xstats));
|
||||||
|
xstats.type = TCA_FQ_CODEL_XSTATS_CLASS;
|
||||||
|
xstats.class_stats.deficit = flow->deficit;
|
||||||
|
xstats.class_stats.ldelay =
|
||||||
|
codel_time_to_us(flow->cvars.ldelay);
|
||||||
|
xstats.class_stats.count = flow->cvars.count;
|
||||||
|
xstats.class_stats.lastcount = flow->cvars.lastcount;
|
||||||
|
xstats.class_stats.dropping = flow->cvars.dropping;
|
||||||
|
if (flow->cvars.dropping) {
|
||||||
|
codel_tdiff_t delta = flow->cvars.drop_next -
|
||||||
|
codel_get_time();
|
||||||
|
|
||||||
|
xstats.class_stats.drop_next = (delta >= 0) ?
|
||||||
|
codel_time_to_us(delta) :
|
||||||
|
-codel_time_to_us(-delta);
|
||||||
|
}
|
||||||
|
while (skb) {
|
||||||
|
qs.qlen++;
|
||||||
|
skb = skb->next;
|
||||||
|
}
|
||||||
|
qs.backlog = q->backlogs[idx];
|
||||||
|
qs.drops = flow->dropped;
|
||||||
|
}
|
||||||
|
if (gnet_stats_copy_queue(d, &qs) < 0)
|
||||||
|
return -1;
|
||||||
|
if (idx < q->flows_cnt)
|
||||||
|
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg)
|
||||||
|
{
|
||||||
|
struct fq_codel_sched_data *q = qdisc_priv(sch);
|
||||||
|
unsigned int i;
|
||||||
|
|
||||||
|
if (arg->stop)
|
||||||
|
return;
|
||||||
|
|
||||||
|
for (i = 0; i < q->flows_cnt; i++) {
|
||||||
|
if (list_empty(&q->flows[i].flowchain) ||
|
||||||
|
arg->count < arg->skip) {
|
||||||
|
arg->count++;
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
if (arg->fn(sch, i + 1, arg) < 0) {
|
||||||
|
arg->stop = 1;
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
arg->count++;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
static const struct Qdisc_class_ops fq_codel_class_ops = {
|
||||||
|
.leaf = fq_codel_leaf,
|
||||||
|
.get = fq_codel_get,
|
||||||
|
.put = fq_codel_put,
|
||||||
|
.tcf_chain = fq_codel_find_tcf,
|
||||||
|
.bind_tcf = fq_codel_bind,
|
||||||
|
.unbind_tcf = fq_codel_put,
|
||||||
|
.dump = fq_codel_dump_class,
|
||||||
|
.dump_stats = fq_codel_dump_class_stats,
|
||||||
|
.walk = fq_codel_walk,
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = {
|
||||||
|
.cl_ops = &fq_codel_class_ops,
|
||||||
|
.id = "fq_codel",
|
||||||
|
.priv_size = sizeof(struct fq_codel_sched_data),
|
||||||
|
.enqueue = fq_codel_enqueue,
|
||||||
|
.dequeue = fq_codel_dequeue,
|
||||||
|
.peek = qdisc_peek_dequeued,
|
||||||
|
.drop = fq_codel_drop,
|
||||||
|
.init = fq_codel_init,
|
||||||
|
.reset = fq_codel_reset,
|
||||||
|
.destroy = fq_codel_destroy,
|
||||||
|
.change = fq_codel_change,
|
||||||
|
.dump = fq_codel_dump,
|
||||||
|
.dump_stats = fq_codel_dump_stats,
|
||||||
|
.owner = THIS_MODULE,
|
||||||
|
};
|
||||||
|
|
||||||
|
static int __init fq_codel_module_init(void)
|
||||||
|
{
|
||||||
|
return register_qdisc(&fq_codel_qdisc_ops);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void __exit fq_codel_module_exit(void)
|
||||||
|
{
|
||||||
|
unregister_qdisc(&fq_codel_qdisc_ops);
|
||||||
|
}
|
||||||
|
|
||||||
|
module_init(fq_codel_module_init)
|
||||||
|
module_exit(fq_codel_module_exit)
|
||||||
|
MODULE_AUTHOR("Eric Dumazet");
|
||||||
|
MODULE_LICENSE("GPL");
|
||||||
Loading…
Reference in a new issue