diff options
author | Eric Dumazet <edumazet@google.com> | 2012-05-11 05:30:50 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2012-05-12 15:53:42 -0400 |
commit | 4b549a2ef4bef9965d97cbd992ba67930cd3e0fe (patch) | |
tree | 2b30a5af713817396ca0c259cddbb2e0972a03e7 /net | |
parent | 536edd67109df5e0cdb2c4ee759e9bade7976367 (diff) |
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>
Diffstat (limited to 'net')
-rw-r--r-- | net/sched/Kconfig | 11 | ||||
-rw-r--r-- | net/sched/Makefile | 1 | ||||
-rw-r--r-- | net/sched/sch_fq_codel.c | 624 |
3 files changed, 636 insertions, 0 deletions
diff --git a/net/sched/Kconfig b/net/sched/Kconfig index fadd2522053d..e7a8976bf25c 100644 --- a/net/sched/Kconfig +++ b/net/sched/Kconfig | |||
@@ -261,6 +261,17 @@ config NET_SCH_CODEL | |||
261 | 261 | ||
262 | If unsure, say N. | 262 | If unsure, say N. |
263 | 263 | ||
264 | config NET_SCH_FQ_CODEL | ||
265 | tristate "Fair Queue Controlled Delay AQM (FQ_CODEL)" | ||
266 | help | ||
267 | Say Y here if you want to use the FQ Controlled Delay (FQ_CODEL) | ||
268 | packet scheduling algorithm. | ||
269 | |||
270 | To compile this driver as a module, choose M here: the module | ||
271 | will be called sch_fq_codel. | ||
272 | |||
273 | If unsure, say N. | ||
274 | |||
264 | config NET_SCH_INGRESS | 275 | config NET_SCH_INGRESS |
265 | tristate "Ingress Qdisc" | 276 | tristate "Ingress Qdisc" |
266 | depends on NET_CLS_ACT | 277 | depends on NET_CLS_ACT |
diff --git a/net/sched/Makefile b/net/sched/Makefile index 30fab03b8516..5940a1992f0d 100644 --- a/net/sched/Makefile +++ b/net/sched/Makefile | |||
@@ -38,6 +38,7 @@ obj-$(CONFIG_NET_SCH_MQPRIO) += sch_mqprio.o | |||
38 | obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o | 38 | obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o |
39 | obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o | 39 | obj-$(CONFIG_NET_SCH_QFQ) += sch_qfq.o |
40 | obj-$(CONFIG_NET_SCH_CODEL) += sch_codel.o | 40 | obj-$(CONFIG_NET_SCH_CODEL) += sch_codel.o |
41 | obj-$(CONFIG_NET_SCH_FQ_CODEL) += sch_fq_codel.o | ||
41 | 42 | ||
42 | obj-$(CONFIG_NET_CLS_U32) += cls_u32.o | 43 | obj-$(CONFIG_NET_CLS_U32) += cls_u32.o |
43 | obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o | 44 | obj-$(CONFIG_NET_CLS_ROUTE4) += cls_route.o |
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c new file mode 100644 index 000000000000..a7b3754d21c8 --- /dev/null +++ b/net/sched/sch_fq_codel.c | |||
@@ -0,0 +1,624 @@ | |||
1 | /* | ||
2 | * Fair Queue CoDel discipline | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or | ||
5 | * modify it under the terms of the GNU General Public License | ||
6 | * as published by the Free Software Foundation; either version | ||
7 | * 2 of the License, or (at your option) any later version. | ||
8 | * | ||
9 | * Copyright (C) 2012 Eric Dumazet <edumazet@google.com> | ||
10 | */ | ||
11 | |||
12 | #include <linux/module.h> | ||
13 | #include <linux/types.h> | ||
14 | #include <linux/kernel.h> | ||
15 | #include <linux/jiffies.h> | ||
16 | #include <linux/string.h> | ||
17 | #include <linux/in.h> | ||
18 | #include <linux/errno.h> | ||
19 | #include <linux/init.h> | ||
20 | #include <linux/skbuff.h> | ||
21 | #include <linux/jhash.h> | ||
22 | #include <linux/slab.h> | ||
23 | #include <linux/vmalloc.h> | ||
24 | #include <net/netlink.h> | ||
25 | #include <net/pkt_sched.h> | ||
26 | #include <net/flow_keys.h> | ||
27 | #include <net/codel.h> | ||
28 | |||
29 | /* Fair Queue CoDel. | ||
30 | * | ||
31 | * Principles : | ||
32 | * Packets are classified (internal classifier or external) on flows. | ||
33 | * This is a Stochastic model (as we use a hash, several flows | ||
34 | * might be hashed on same slot) | ||
35 | * Each flow has a CoDel managed queue. | ||
36 | * Flows are linked onto two (Round Robin) lists, | ||
37 | * so that new flows have priority on old ones. | ||
38 | * | ||
39 | * For a given flow, packets are not reordered (CoDel uses a FIFO) | ||
40 | * head drops only. | ||
41 | * ECN capability is on by default. | ||
42 | * Low memory footprint (64 bytes per flow) | ||
43 | */ | ||
44 | |||
45 | struct fq_codel_flow { | ||
46 | struct sk_buff *head; | ||
47 | struct sk_buff *tail; | ||
48 | struct list_head flowchain; | ||
49 | int deficit; | ||
50 | u32 dropped; /* number of drops (or ECN marks) on this flow */ | ||
51 | struct codel_vars cvars; | ||
52 | }; /* please try to keep this structure <= 64 bytes */ | ||
53 | |||
54 | struct fq_codel_sched_data { | ||
55 | struct tcf_proto *filter_list; /* optional external classifier */ | ||
56 | struct fq_codel_flow *flows; /* Flows table [flows_cnt] */ | ||
57 | u32 *backlogs; /* backlog table [flows_cnt] */ | ||
58 | u32 flows_cnt; /* number of flows */ | ||
59 | u32 perturbation; /* hash perturbation */ | ||
60 | u32 quantum; /* psched_mtu(qdisc_dev(sch)); */ | ||
61 | struct codel_params cparams; | ||
62 | struct codel_stats cstats; | ||
63 | u32 drop_overlimit; | ||
64 | u32 new_flow_count; | ||
65 | |||
66 | struct list_head new_flows; /* list of new flows */ | ||
67 | struct list_head old_flows; /* list of old flows */ | ||
68 | }; | ||
69 | |||
70 | static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q, | ||
71 | const struct sk_buff *skb) | ||
72 | { | ||
73 | struct flow_keys keys; | ||
74 | unsigned int hash; | ||
75 | |||
76 | skb_flow_dissect(skb, &keys); | ||
77 | hash = jhash_3words((__force u32)keys.dst, | ||
78 | (__force u32)keys.src ^ keys.ip_proto, | ||
79 | (__force u32)keys.ports, q->perturbation); | ||
80 | return ((u64)hash * q->flows_cnt) >> 32; | ||
81 | } | ||
82 | |||
83 | static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch, | ||
84 | int *qerr) | ||
85 | { | ||
86 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
87 | struct tcf_result res; | ||
88 | int result; | ||
89 | |||
90 | if (TC_H_MAJ(skb->priority) == sch->handle && | ||
91 | TC_H_MIN(skb->priority) > 0 && | ||
92 | TC_H_MIN(skb->priority) <= q->flows_cnt) | ||
93 | return TC_H_MIN(skb->priority); | ||
94 | |||
95 | if (!q->filter_list) | ||
96 | return fq_codel_hash(q, skb) + 1; | ||
97 | |||
98 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; | ||
99 | result = tc_classify(skb, q->filter_list, &res); | ||
100 | if (result >= 0) { | ||
101 | #ifdef CONFIG_NET_CLS_ACT | ||
102 | switch (result) { | ||
103 | case TC_ACT_STOLEN: | ||
104 | case TC_ACT_QUEUED: | ||
105 | *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; | ||
106 | case TC_ACT_SHOT: | ||
107 | return 0; | ||
108 | } | ||
109 | #endif | ||
110 | if (TC_H_MIN(res.classid) <= q->flows_cnt) | ||
111 | return TC_H_MIN(res.classid); | ||
112 | } | ||
113 | return 0; | ||
114 | } | ||
115 | |||
116 | /* helper functions : might be changed when/if skb use a standard list_head */ | ||
117 | |||
118 | /* remove one skb from head of slot queue */ | ||
119 | static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow) | ||
120 | { | ||
121 | struct sk_buff *skb = flow->head; | ||
122 | |||
123 | flow->head = skb->next; | ||
124 | skb->next = NULL; | ||
125 | return skb; | ||
126 | } | ||
127 | |||
128 | /* add skb to flow queue (tail add) */ | ||
129 | static inline void flow_queue_add(struct fq_codel_flow *flow, | ||
130 | struct sk_buff *skb) | ||
131 | { | ||
132 | if (flow->head == NULL) | ||
133 | flow->head = skb; | ||
134 | else | ||
135 | flow->tail->next = skb; | ||
136 | flow->tail = skb; | ||
137 | skb->next = NULL; | ||
138 | } | ||
139 | |||
140 | static unsigned int fq_codel_drop(struct Qdisc *sch) | ||
141 | { | ||
142 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
143 | struct sk_buff *skb; | ||
144 | unsigned int maxbacklog = 0, idx = 0, i, len; | ||
145 | struct fq_codel_flow *flow; | ||
146 | |||
147 | /* Queue is full! Find the fat flow and drop packet from it. | ||
148 | * This might sound expensive, but with 1024 flows, we scan | ||
149 | * 4KB of memory, and we dont need to handle a complex tree | ||
150 | * in fast path (packet queue/enqueue) with many cache misses. | ||
151 | */ | ||
152 | for (i = 0; i < q->flows_cnt; i++) { | ||
153 | if (q->backlogs[i] > maxbacklog) { | ||
154 | maxbacklog = q->backlogs[i]; | ||
155 | idx = i; | ||
156 | } | ||
157 | } | ||
158 | flow = &q->flows[idx]; | ||
159 | skb = dequeue_head(flow); | ||
160 | len = qdisc_pkt_len(skb); | ||
161 | q->backlogs[idx] -= len; | ||
162 | kfree_skb(skb); | ||
163 | sch->q.qlen--; | ||
164 | sch->qstats.drops++; | ||
165 | sch->qstats.backlog -= len; | ||
166 | flow->dropped++; | ||
167 | return idx; | ||
168 | } | ||
169 | |||
170 | static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch) | ||
171 | { | ||
172 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
173 | unsigned int idx; | ||
174 | struct fq_codel_flow *flow; | ||
175 | int uninitialized_var(ret); | ||
176 | |||
177 | idx = fq_codel_classify(skb, sch, &ret); | ||
178 | if (idx == 0) { | ||
179 | if (ret & __NET_XMIT_BYPASS) | ||
180 | sch->qstats.drops++; | ||
181 | kfree_skb(skb); | ||
182 | return ret; | ||
183 | } | ||
184 | idx--; | ||
185 | |||
186 | codel_set_enqueue_time(skb); | ||
187 | flow = &q->flows[idx]; | ||
188 | flow_queue_add(flow, skb); | ||
189 | q->backlogs[idx] += qdisc_pkt_len(skb); | ||
190 | sch->qstats.backlog += qdisc_pkt_len(skb); | ||
191 | |||
192 | if (list_empty(&flow->flowchain)) { | ||
193 | list_add_tail(&flow->flowchain, &q->new_flows); | ||
194 | codel_vars_init(&flow->cvars); | ||
195 | q->new_flow_count++; | ||
196 | flow->deficit = q->quantum; | ||
197 | flow->dropped = 0; | ||
198 | } | ||
199 | if (++sch->q.qlen < sch->limit) | ||
200 | return NET_XMIT_SUCCESS; | ||
201 | |||
202 | q->drop_overlimit++; | ||
203 | /* Return Congestion Notification only if we dropped a packet | ||
204 | * from this flow. | ||
205 | */ | ||
206 | if (fq_codel_drop(sch) == idx) | ||
207 | return NET_XMIT_CN; | ||
208 | |||
209 | /* As we dropped a packet, better let upper stack know this */ | ||
210 | qdisc_tree_decrease_qlen(sch, 1); | ||
211 | return NET_XMIT_SUCCESS; | ||
212 | } | ||
213 | |||
214 | /* This is the specific function called from codel_dequeue() | ||
215 | * to dequeue a packet from queue. Note: backlog is handled in | ||
216 | * codel, we dont need to reduce it here. | ||
217 | */ | ||
218 | static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch) | ||
219 | { | ||
220 | struct fq_codel_flow *flow; | ||
221 | struct sk_buff *skb = NULL; | ||
222 | |||
223 | flow = container_of(vars, struct fq_codel_flow, cvars); | ||
224 | if (flow->head) { | ||
225 | skb = dequeue_head(flow); | ||
226 | sch->qstats.backlog -= qdisc_pkt_len(skb); | ||
227 | sch->q.qlen--; | ||
228 | } | ||
229 | return skb; | ||
230 | } | ||
231 | |||
232 | static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch) | ||
233 | { | ||
234 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
235 | struct sk_buff *skb; | ||
236 | struct fq_codel_flow *flow; | ||
237 | struct list_head *head; | ||
238 | u32 prev_drop_count, prev_ecn_mark; | ||
239 | |||
240 | begin: | ||
241 | head = &q->new_flows; | ||
242 | if (list_empty(head)) { | ||
243 | head = &q->old_flows; | ||
244 | if (list_empty(head)) | ||
245 | return NULL; | ||
246 | } | ||
247 | flow = list_first_entry(head, struct fq_codel_flow, flowchain); | ||
248 | |||
249 | if (flow->deficit <= 0) { | ||
250 | flow->deficit += q->quantum; | ||
251 | list_move_tail(&flow->flowchain, &q->old_flows); | ||
252 | goto begin; | ||
253 | } | ||
254 | |||
255 | prev_drop_count = q->cstats.drop_count; | ||
256 | prev_ecn_mark = q->cstats.ecn_mark; | ||
257 | |||
258 | skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats, | ||
259 | dequeue, &q->backlogs[flow - q->flows]); | ||
260 | |||
261 | flow->dropped += q->cstats.drop_count - prev_drop_count; | ||
262 | flow->dropped += q->cstats.ecn_mark - prev_ecn_mark; | ||
263 | |||
264 | if (!skb) { | ||
265 | /* force a pass through old_flows to prevent starvation */ | ||
266 | if ((head == &q->new_flows) && !list_empty(&q->old_flows)) | ||
267 | list_move_tail(&flow->flowchain, &q->old_flows); | ||
268 | else | ||
269 | list_del_init(&flow->flowchain); | ||
270 | goto begin; | ||
271 | } | ||
272 | qdisc_bstats_update(sch, skb); | ||
273 | flow->deficit -= qdisc_pkt_len(skb); | ||
274 | /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0, | ||
275 | * or HTB crashes. Defer it for next round. | ||
276 | */ | ||
277 | if (q->cstats.drop_count && sch->q.qlen) { | ||
278 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | ||
279 | q->cstats.drop_count = 0; | ||
280 | } | ||
281 | return skb; | ||
282 | } | ||
283 | |||
284 | static void fq_codel_reset(struct Qdisc *sch) | ||
285 | { | ||
286 | struct sk_buff *skb; | ||
287 | |||
288 | while ((skb = fq_codel_dequeue(sch)) != NULL) | ||
289 | kfree_skb(skb); | ||
290 | } | ||
291 | |||
292 | static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = { | ||
293 | [TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 }, | ||
294 | [TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 }, | ||
295 | [TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 }, | ||
296 | [TCA_FQ_CODEL_ECN] = { .type = NLA_U32 }, | ||
297 | [TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 }, | ||
298 | [TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 }, | ||
299 | }; | ||
300 | |||
301 | static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt) | ||
302 | { | ||
303 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
304 | struct nlattr *tb[TCA_FQ_CODEL_MAX + 1]; | ||
305 | int err; | ||
306 | |||
307 | if (!opt) | ||
308 | return -EINVAL; | ||
309 | |||
310 | err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy); | ||
311 | if (err < 0) | ||
312 | return err; | ||
313 | if (tb[TCA_FQ_CODEL_FLOWS]) { | ||
314 | if (q->flows) | ||
315 | return -EINVAL; | ||
316 | q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]); | ||
317 | if (!q->flows_cnt || | ||
318 | q->flows_cnt > 65536) | ||
319 | return -EINVAL; | ||
320 | } | ||
321 | sch_tree_lock(sch); | ||
322 | |||
323 | if (tb[TCA_FQ_CODEL_TARGET]) { | ||
324 | u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]); | ||
325 | |||
326 | q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT; | ||
327 | } | ||
328 | |||
329 | if (tb[TCA_FQ_CODEL_INTERVAL]) { | ||
330 | u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]); | ||
331 | |||
332 | q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT; | ||
333 | } | ||
334 | |||
335 | if (tb[TCA_FQ_CODEL_LIMIT]) | ||
336 | sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]); | ||
337 | |||
338 | if (tb[TCA_FQ_CODEL_ECN]) | ||
339 | q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]); | ||
340 | |||
341 | if (tb[TCA_FQ_CODEL_QUANTUM]) | ||
342 | q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM])); | ||
343 | |||
344 | while (sch->q.qlen > sch->limit) { | ||
345 | struct sk_buff *skb = fq_codel_dequeue(sch); | ||
346 | |||
347 | kfree_skb(skb); | ||
348 | q->cstats.drop_count++; | ||
349 | } | ||
350 | qdisc_tree_decrease_qlen(sch, q->cstats.drop_count); | ||
351 | q->cstats.drop_count = 0; | ||
352 | |||
353 | sch_tree_unlock(sch); | ||
354 | return 0; | ||
355 | } | ||
356 | |||
357 | static void *fq_codel_zalloc(size_t sz) | ||
358 | { | ||
359 | void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN); | ||
360 | |||
361 | if (!ptr) | ||
362 | ptr = vzalloc(sz); | ||
363 | return ptr; | ||
364 | } | ||
365 | |||
366 | static void fq_codel_free(void *addr) | ||
367 | { | ||
368 | if (addr) { | ||
369 | if (is_vmalloc_addr(addr)) | ||
370 | vfree(addr); | ||
371 | else | ||
372 | kfree(addr); | ||
373 | } | ||
374 | } | ||
375 | |||
376 | static void fq_codel_destroy(struct Qdisc *sch) | ||
377 | { | ||
378 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
379 | |||
380 | tcf_destroy_chain(&q->filter_list); | ||
381 | fq_codel_free(q->backlogs); | ||
382 | fq_codel_free(q->flows); | ||
383 | } | ||
384 | |||
385 | static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt) | ||
386 | { | ||
387 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
388 | int i; | ||
389 | |||
390 | sch->limit = 10*1024; | ||
391 | q->flows_cnt = 1024; | ||
392 | q->quantum = psched_mtu(qdisc_dev(sch)); | ||
393 | q->perturbation = net_random(); | ||
394 | INIT_LIST_HEAD(&q->new_flows); | ||
395 | INIT_LIST_HEAD(&q->old_flows); | ||
396 | codel_params_init(&q->cparams); | ||
397 | codel_stats_init(&q->cstats); | ||
398 | q->cparams.ecn = true; | ||
399 | |||
400 | if (opt) { | ||
401 | int err = fq_codel_change(sch, opt); | ||
402 | if (err) | ||
403 | return err; | ||
404 | } | ||
405 | |||
406 | if (!q->flows) { | ||
407 | q->flows = fq_codel_zalloc(q->flows_cnt * | ||
408 | sizeof(struct fq_codel_flow)); | ||
409 | if (!q->flows) | ||
410 | return -ENOMEM; | ||
411 | q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32)); | ||
412 | if (!q->backlogs) { | ||
413 | fq_codel_free(q->flows); | ||
414 | return -ENOMEM; | ||
415 | } | ||
416 | for (i = 0; i < q->flows_cnt; i++) { | ||
417 | struct fq_codel_flow *flow = q->flows + i; | ||
418 | |||
419 | INIT_LIST_HEAD(&flow->flowchain); | ||
420 | } | ||
421 | } | ||
422 | if (sch->limit >= 1) | ||
423 | sch->flags |= TCQ_F_CAN_BYPASS; | ||
424 | else | ||
425 | sch->flags &= ~TCQ_F_CAN_BYPASS; | ||
426 | return 0; | ||
427 | } | ||
428 | |||
429 | static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb) | ||
430 | { | ||
431 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
432 | struct nlattr *opts; | ||
433 | |||
434 | opts = nla_nest_start(skb, TCA_OPTIONS); | ||
435 | if (opts == NULL) | ||
436 | goto nla_put_failure; | ||
437 | |||
438 | if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET, | ||
439 | codel_time_to_us(q->cparams.target)) || | ||
440 | nla_put_u32(skb, TCA_FQ_CODEL_LIMIT, | ||
441 | sch->limit) || | ||
442 | nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL, | ||
443 | codel_time_to_us(q->cparams.interval)) || | ||
444 | nla_put_u32(skb, TCA_FQ_CODEL_ECN, | ||
445 | q->cparams.ecn) || | ||
446 | nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM, | ||
447 | q->quantum) || | ||
448 | nla_put_u32(skb, TCA_FQ_CODEL_FLOWS, | ||
449 | q->flows_cnt)) | ||
450 | goto nla_put_failure; | ||
451 | |||
452 | nla_nest_end(skb, opts); | ||
453 | return skb->len; | ||
454 | |||
455 | nla_put_failure: | ||
456 | return -1; | ||
457 | } | ||
458 | |||
459 | static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d) | ||
460 | { | ||
461 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
462 | struct tc_fq_codel_xstats st = { | ||
463 | .type = TCA_FQ_CODEL_XSTATS_QDISC, | ||
464 | .qdisc_stats.maxpacket = q->cstats.maxpacket, | ||
465 | .qdisc_stats.drop_overlimit = q->drop_overlimit, | ||
466 | .qdisc_stats.ecn_mark = q->cstats.ecn_mark, | ||
467 | .qdisc_stats.new_flow_count = q->new_flow_count, | ||
468 | }; | ||
469 | struct list_head *pos; | ||
470 | |||
471 | list_for_each(pos, &q->new_flows) | ||
472 | st.qdisc_stats.new_flows_len++; | ||
473 | |||
474 | list_for_each(pos, &q->old_flows) | ||
475 | st.qdisc_stats.old_flows_len++; | ||
476 | |||
477 | return gnet_stats_copy_app(d, &st, sizeof(st)); | ||
478 | } | ||
479 | |||
480 | static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg) | ||
481 | { | ||
482 | return NULL; | ||
483 | } | ||
484 | |||
485 | static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid) | ||
486 | { | ||
487 | return 0; | ||
488 | } | ||
489 | |||
490 | static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent, | ||
491 | u32 classid) | ||
492 | { | ||
493 | /* we cannot bypass queue discipline anymore */ | ||
494 | sch->flags &= ~TCQ_F_CAN_BYPASS; | ||
495 | return 0; | ||
496 | } | ||
497 | |||
498 | static void fq_codel_put(struct Qdisc *q, unsigned long cl) | ||
499 | { | ||
500 | } | ||
501 | |||
502 | static struct tcf_proto **fq_codel_find_tcf(struct Qdisc *sch, unsigned long cl) | ||
503 | { | ||
504 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
505 | |||
506 | if (cl) | ||
507 | return NULL; | ||
508 | return &q->filter_list; | ||
509 | } | ||
510 | |||
511 | static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl, | ||
512 | struct sk_buff *skb, struct tcmsg *tcm) | ||
513 | { | ||
514 | tcm->tcm_handle |= TC_H_MIN(cl); | ||
515 | return 0; | ||
516 | } | ||
517 | |||
518 | static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl, | ||
519 | struct gnet_dump *d) | ||
520 | { | ||
521 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
522 | u32 idx = cl - 1; | ||
523 | struct gnet_stats_queue qs = { 0 }; | ||
524 | struct tc_fq_codel_xstats xstats; | ||
525 | |||
526 | if (idx < q->flows_cnt) { | ||
527 | const struct fq_codel_flow *flow = &q->flows[idx]; | ||
528 | const struct sk_buff *skb = flow->head; | ||
529 | |||
530 | memset(&xstats, 0, sizeof(xstats)); | ||
531 | xstats.type = TCA_FQ_CODEL_XSTATS_CLASS; | ||
532 | xstats.class_stats.deficit = flow->deficit; | ||
533 | xstats.class_stats.ldelay = | ||
534 | codel_time_to_us(flow->cvars.ldelay); | ||
535 | xstats.class_stats.count = flow->cvars.count; | ||
536 | xstats.class_stats.lastcount = flow->cvars.lastcount; | ||
537 | xstats.class_stats.dropping = flow->cvars.dropping; | ||
538 | if (flow->cvars.dropping) { | ||
539 | codel_tdiff_t delta = flow->cvars.drop_next - | ||
540 | codel_get_time(); | ||
541 | |||
542 | xstats.class_stats.drop_next = (delta >= 0) ? | ||
543 | codel_time_to_us(delta) : | ||
544 | -codel_time_to_us(-delta); | ||
545 | } | ||
546 | while (skb) { | ||
547 | qs.qlen++; | ||
548 | skb = skb->next; | ||
549 | } | ||
550 | qs.backlog = q->backlogs[idx]; | ||
551 | qs.drops = flow->dropped; | ||
552 | } | ||
553 | if (gnet_stats_copy_queue(d, &qs) < 0) | ||
554 | return -1; | ||
555 | if (idx < q->flows_cnt) | ||
556 | return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); | ||
557 | return 0; | ||
558 | } | ||
559 | |||
560 | static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg) | ||
561 | { | ||
562 | struct fq_codel_sched_data *q = qdisc_priv(sch); | ||
563 | unsigned int i; | ||
564 | |||
565 | if (arg->stop) | ||
566 | return; | ||
567 | |||
568 | for (i = 0; i < q->flows_cnt; i++) { | ||
569 | if (list_empty(&q->flows[i].flowchain) || | ||
570 | arg->count < arg->skip) { | ||
571 | arg->count++; | ||
572 | continue; | ||
573 | } | ||
574 | if (arg->fn(sch, i + 1, arg) < 0) { | ||
575 | arg->stop = 1; | ||
576 | break; | ||
577 | } | ||
578 | arg->count++; | ||
579 | } | ||
580 | } | ||
581 | |||
582 | static const struct Qdisc_class_ops fq_codel_class_ops = { | ||
583 | .leaf = fq_codel_leaf, | ||
584 | .get = fq_codel_get, | ||
585 | .put = fq_codel_put, | ||
586 | .tcf_chain = fq_codel_find_tcf, | ||
587 | .bind_tcf = fq_codel_bind, | ||
588 | .unbind_tcf = fq_codel_put, | ||
589 | .dump = fq_codel_dump_class, | ||
590 | .dump_stats = fq_codel_dump_class_stats, | ||
591 | .walk = fq_codel_walk, | ||
592 | }; | ||
593 | |||
594 | static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = { | ||
595 | .cl_ops = &fq_codel_class_ops, | ||
596 | .id = "fq_codel", | ||
597 | .priv_size = sizeof(struct fq_codel_sched_data), | ||
598 | .enqueue = fq_codel_enqueue, | ||
599 | .dequeue = fq_codel_dequeue, | ||
600 | .peek = qdisc_peek_dequeued, | ||
601 | .drop = fq_codel_drop, | ||
602 | .init = fq_codel_init, | ||
603 | .reset = fq_codel_reset, | ||
604 | .destroy = fq_codel_destroy, | ||
605 | .change = fq_codel_change, | ||
606 | .dump = fq_codel_dump, | ||
607 | .dump_stats = fq_codel_dump_stats, | ||
608 | .owner = THIS_MODULE, | ||
609 | }; | ||
610 | |||
611 | static int __init fq_codel_module_init(void) | ||
612 | { | ||
613 | return register_qdisc(&fq_codel_qdisc_ops); | ||
614 | } | ||
615 | |||
616 | static void __exit fq_codel_module_exit(void) | ||
617 | { | ||
618 | unregister_qdisc(&fq_codel_qdisc_ops); | ||
619 | } | ||
620 | |||
621 | module_init(fq_codel_module_init) | ||
622 | module_exit(fq_codel_module_exit) | ||
623 | MODULE_AUTHOR("Eric Dumazet"); | ||
624 | MODULE_LICENSE("GPL"); | ||