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fb9e53cc | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
557fc4a0 MK |
2 | /* |
3 | * Copyright (c) 2016 Qualcomm Atheros, Inc | |
4 | * | |
557fc4a0 MK |
5 | * Based on net/sched/sch_fq_codel.c |
6 | */ | |
7 | #ifndef __NET_SCHED_FQ_IMPL_H | |
8 | #define __NET_SCHED_FQ_IMPL_H | |
9 | ||
10 | #include <net/fq.h> | |
11 | ||
12 | /* functions that are embedded into includer */ | |
13 | ||
07be2fed FF |
14 | |
15 | static void | |
16 | __fq_adjust_removal(struct fq *fq, struct fq_flow *flow, unsigned int packets, | |
17 | unsigned int bytes, unsigned int truesize) | |
18 | { | |
19 | struct fq_tin *tin = flow->tin; | |
d7b64929 | 20 | int idx; |
07be2fed FF |
21 | |
22 | tin->backlog_bytes -= bytes; | |
23 | tin->backlog_packets -= packets; | |
24 | flow->backlog -= bytes; | |
25 | fq->backlog -= packets; | |
26 | fq->memory_usage -= truesize; | |
d7b64929 FF |
27 | |
28 | if (flow->backlog) | |
29 | return; | |
30 | ||
31 | if (flow == &tin->default_flow) { | |
32 | list_del_init(&tin->tin_list); | |
33 | return; | |
34 | } | |
35 | ||
36 | idx = flow - fq->flows; | |
37 | __clear_bit(idx, fq->flows_bitmap); | |
07be2fed FF |
38 | } |
39 | ||
8c418b5b JB |
40 | static void fq_adjust_removal(struct fq *fq, |
41 | struct fq_flow *flow, | |
42 | struct sk_buff *skb) | |
557fc4a0 | 43 | { |
07be2fed | 44 | __fq_adjust_removal(fq, flow, 1, skb->len, skb->truesize); |
8c418b5b JB |
45 | } |
46 | ||
8c418b5b JB |
47 | static struct sk_buff *fq_flow_dequeue(struct fq *fq, |
48 | struct fq_flow *flow) | |
49 | { | |
50 | struct sk_buff *skb; | |
51 | ||
52 | lockdep_assert_held(&fq->lock); | |
53 | ||
54 | skb = __skb_dequeue(&flow->queue); | |
55 | if (!skb) | |
56 | return NULL; | |
57 | ||
58 | fq_adjust_removal(fq, flow, skb); | |
557fc4a0 MK |
59 | |
60 | return skb; | |
61 | } | |
62 | ||
07be2fed FF |
63 | static int fq_flow_drop(struct fq *fq, struct fq_flow *flow, |
64 | fq_skb_free_t free_func) | |
65 | { | |
66 | unsigned int packets = 0, bytes = 0, truesize = 0; | |
67 | struct fq_tin *tin = flow->tin; | |
68 | struct sk_buff *skb; | |
69 | int pending; | |
70 | ||
71 | lockdep_assert_held(&fq->lock); | |
72 | ||
73 | pending = min_t(int, 32, skb_queue_len(&flow->queue) / 2); | |
74 | do { | |
75 | skb = __skb_dequeue(&flow->queue); | |
76 | if (!skb) | |
77 | break; | |
78 | ||
79 | packets++; | |
80 | bytes += skb->len; | |
81 | truesize += skb->truesize; | |
82 | free_func(fq, tin, flow, skb); | |
83 | } while (packets < pending); | |
84 | ||
85 | __fq_adjust_removal(fq, flow, packets, bytes, truesize); | |
07be2fed FF |
86 | |
87 | return packets; | |
88 | } | |
89 | ||
557fc4a0 MK |
90 | static struct sk_buff *fq_tin_dequeue(struct fq *fq, |
91 | struct fq_tin *tin, | |
92 | fq_tin_dequeue_t dequeue_func) | |
93 | { | |
94 | struct fq_flow *flow; | |
95 | struct list_head *head; | |
96 | struct sk_buff *skb; | |
97 | ||
98 | lockdep_assert_held(&fq->lock); | |
99 | ||
100 | begin: | |
101 | head = &tin->new_flows; | |
102 | if (list_empty(head)) { | |
103 | head = &tin->old_flows; | |
104 | if (list_empty(head)) | |
105 | return NULL; | |
106 | } | |
107 | ||
108 | flow = list_first_entry(head, struct fq_flow, flowchain); | |
109 | ||
110 | if (flow->deficit <= 0) { | |
111 | flow->deficit += fq->quantum; | |
112 | list_move_tail(&flow->flowchain, | |
113 | &tin->old_flows); | |
114 | goto begin; | |
115 | } | |
116 | ||
117 | skb = dequeue_func(fq, tin, flow); | |
118 | if (!skb) { | |
119 | /* force a pass through old_flows to prevent starvation */ | |
120 | if ((head == &tin->new_flows) && | |
121 | !list_empty(&tin->old_flows)) { | |
122 | list_move_tail(&flow->flowchain, &tin->old_flows); | |
123 | } else { | |
124 | list_del_init(&flow->flowchain); | |
125 | flow->tin = NULL; | |
126 | } | |
127 | goto begin; | |
128 | } | |
129 | ||
130 | flow->deficit -= skb->len; | |
131 | tin->tx_bytes += skb->len; | |
132 | tin->tx_packets++; | |
133 | ||
134 | return skb; | |
135 | } | |
136 | ||
f2af2df8 FF |
137 | static u32 fq_flow_idx(struct fq *fq, struct sk_buff *skb) |
138 | { | |
48a54f6b | 139 | u32 hash = skb_get_hash(skb); |
f2af2df8 FF |
140 | |
141 | return reciprocal_scale(hash, fq->flows_cnt); | |
142 | } | |
143 | ||
557fc4a0 | 144 | static struct fq_flow *fq_flow_classify(struct fq *fq, |
f2af2df8 | 145 | struct fq_tin *tin, u32 idx, |
bf9009bf | 146 | struct sk_buff *skb) |
557fc4a0 MK |
147 | { |
148 | struct fq_flow *flow; | |
557fc4a0 MK |
149 | |
150 | lockdep_assert_held(&fq->lock); | |
151 | ||
557fc4a0 | 152 | flow = &fq->flows[idx]; |
557fc4a0 | 153 | if (flow->tin && flow->tin != tin) { |
bf9009bf | 154 | flow = &tin->default_flow; |
557fc4a0 MK |
155 | tin->collisions++; |
156 | fq->collisions++; | |
157 | } | |
158 | ||
159 | if (!flow->tin) | |
160 | tin->flows++; | |
161 | ||
162 | return flow; | |
163 | } | |
164 | ||
d7b64929 | 165 | static struct fq_flow *fq_find_fattest_flow(struct fq *fq) |
b43e7199 | 166 | { |
d7b64929 FF |
167 | struct fq_tin *tin; |
168 | struct fq_flow *flow = NULL; | |
169 | u32 len = 0; | |
170 | int i; | |
b43e7199 | 171 | |
d7b64929 FF |
172 | for_each_set_bit(i, fq->flows_bitmap, fq->flows_cnt) { |
173 | struct fq_flow *cur = &fq->flows[i]; | |
174 | unsigned int cur_len; | |
b43e7199 | 175 | |
d7b64929 FF |
176 | cur_len = cur->backlog; |
177 | if (cur_len <= len) | |
178 | continue; | |
179 | ||
180 | flow = cur; | |
181 | len = cur_len; | |
182 | } | |
183 | ||
184 | list_for_each_entry(tin, &fq->tin_backlog, tin_list) { | |
185 | unsigned int cur_len = tin->default_flow.backlog; | |
b43e7199 | 186 | |
d7b64929 FF |
187 | if (cur_len <= len) |
188 | continue; | |
189 | ||
190 | flow = &tin->default_flow; | |
191 | len = cur_len; | |
192 | } | |
193 | ||
194 | return flow; | |
b43e7199 MK |
195 | } |
196 | ||
557fc4a0 | 197 | static void fq_tin_enqueue(struct fq *fq, |
f2af2df8 | 198 | struct fq_tin *tin, u32 idx, |
557fc4a0 | 199 | struct sk_buff *skb, |
bf9009bf | 200 | fq_skb_free_t free_func) |
557fc4a0 MK |
201 | { |
202 | struct fq_flow *flow; | |
7d360f60 | 203 | struct sk_buff *next; |
0bfe649f | 204 | bool oom; |
557fc4a0 MK |
205 | |
206 | lockdep_assert_held(&fq->lock); | |
207 | ||
bf9009bf | 208 | flow = fq_flow_classify(fq, tin, idx, skb); |
557fc4a0 | 209 | |
d7b64929 FF |
210 | if (!flow->backlog) { |
211 | if (flow != &tin->default_flow) | |
212 | __set_bit(idx, fq->flows_bitmap); | |
213 | else if (list_empty(&tin->tin_list)) | |
214 | list_add(&tin->tin_list, &fq->tin_backlog); | |
215 | } | |
216 | ||
557fc4a0 | 217 | flow->tin = tin; |
7d360f60 FF |
218 | skb_list_walk_safe(skb, skb, next) { |
219 | skb_mark_not_on_list(skb); | |
220 | flow->backlog += skb->len; | |
221 | tin->backlog_bytes += skb->len; | |
222 | tin->backlog_packets++; | |
223 | fq->memory_usage += skb->truesize; | |
224 | fq->backlog++; | |
225 | __skb_queue_tail(&flow->queue, skb); | |
226 | } | |
557fc4a0 | 227 | |
557fc4a0 MK |
228 | if (list_empty(&flow->flowchain)) { |
229 | flow->deficit = fq->quantum; | |
230 | list_add_tail(&flow->flowchain, | |
231 | &tin->new_flows); | |
232 | } | |
233 | ||
0bfe649f THJ |
234 | oom = (fq->memory_usage > fq->memory_limit); |
235 | while (fq->backlog > fq->limit || oom) { | |
d7b64929 | 236 | flow = fq_find_fattest_flow(fq); |
557fc4a0 MK |
237 | if (!flow) |
238 | return; | |
239 | ||
07be2fed | 240 | if (!fq_flow_drop(fq, flow, free_func)) |
557fc4a0 MK |
241 | return; |
242 | ||
557fc4a0 MK |
243 | flow->tin->overlimit++; |
244 | fq->overlimit++; | |
0bfe649f | 245 | if (oom) { |
097b065b | 246 | fq->overmemory++; |
0bfe649f THJ |
247 | oom = (fq->memory_usage > fq->memory_limit); |
248 | } | |
557fc4a0 MK |
249 | } |
250 | } | |
251 | ||
8c418b5b JB |
252 | static void fq_flow_filter(struct fq *fq, |
253 | struct fq_flow *flow, | |
254 | fq_skb_filter_t filter_func, | |
255 | void *filter_data, | |
256 | fq_skb_free_t free_func) | |
257 | { | |
258 | struct fq_tin *tin = flow->tin; | |
259 | struct sk_buff *skb, *tmp; | |
260 | ||
261 | lockdep_assert_held(&fq->lock); | |
262 | ||
263 | skb_queue_walk_safe(&flow->queue, skb, tmp) { | |
264 | if (!filter_func(fq, tin, flow, skb, filter_data)) | |
265 | continue; | |
266 | ||
267 | __skb_unlink(skb, &flow->queue); | |
268 | fq_adjust_removal(fq, flow, skb); | |
269 | free_func(fq, tin, flow, skb); | |
270 | } | |
8c418b5b JB |
271 | } |
272 | ||
273 | static void fq_tin_filter(struct fq *fq, | |
274 | struct fq_tin *tin, | |
275 | fq_skb_filter_t filter_func, | |
276 | void *filter_data, | |
277 | fq_skb_free_t free_func) | |
278 | { | |
279 | struct fq_flow *flow; | |
280 | ||
281 | lockdep_assert_held(&fq->lock); | |
282 | ||
283 | list_for_each_entry(flow, &tin->new_flows, flowchain) | |
284 | fq_flow_filter(fq, flow, filter_func, filter_data, free_func); | |
285 | list_for_each_entry(flow, &tin->old_flows, flowchain) | |
286 | fq_flow_filter(fq, flow, filter_func, filter_data, free_func); | |
287 | } | |
288 | ||
557fc4a0 MK |
289 | static void fq_flow_reset(struct fq *fq, |
290 | struct fq_flow *flow, | |
291 | fq_skb_free_t free_func) | |
292 | { | |
d7b64929 | 293 | struct fq_tin *tin = flow->tin; |
557fc4a0 MK |
294 | struct sk_buff *skb; |
295 | ||
296 | while ((skb = fq_flow_dequeue(fq, flow))) | |
d7b64929 | 297 | free_func(fq, tin, flow, skb); |
557fc4a0 | 298 | |
d7b64929 | 299 | if (!list_empty(&flow->flowchain)) { |
557fc4a0 | 300 | list_del_init(&flow->flowchain); |
d7b64929 FF |
301 | if (list_empty(&tin->new_flows) && |
302 | list_empty(&tin->old_flows)) | |
303 | list_del_init(&tin->tin_list); | |
304 | } | |
557fc4a0 MK |
305 | |
306 | flow->tin = NULL; | |
307 | ||
308 | WARN_ON_ONCE(flow->backlog); | |
309 | } | |
310 | ||
311 | static void fq_tin_reset(struct fq *fq, | |
312 | struct fq_tin *tin, | |
313 | fq_skb_free_t free_func) | |
314 | { | |
315 | struct list_head *head; | |
316 | struct fq_flow *flow; | |
317 | ||
318 | for (;;) { | |
319 | head = &tin->new_flows; | |
320 | if (list_empty(head)) { | |
321 | head = &tin->old_flows; | |
322 | if (list_empty(head)) | |
323 | break; | |
324 | } | |
325 | ||
326 | flow = list_first_entry(head, struct fq_flow, flowchain); | |
327 | fq_flow_reset(fq, flow, free_func); | |
328 | } | |
329 | ||
d7b64929 | 330 | WARN_ON_ONCE(!list_empty(&tin->tin_list)); |
557fc4a0 MK |
331 | WARN_ON_ONCE(tin->backlog_bytes); |
332 | WARN_ON_ONCE(tin->backlog_packets); | |
333 | } | |
334 | ||
335 | static void fq_flow_init(struct fq_flow *flow) | |
336 | { | |
337 | INIT_LIST_HEAD(&flow->flowchain); | |
557fc4a0 MK |
338 | __skb_queue_head_init(&flow->queue); |
339 | } | |
340 | ||
341 | static void fq_tin_init(struct fq_tin *tin) | |
342 | { | |
343 | INIT_LIST_HEAD(&tin->new_flows); | |
344 | INIT_LIST_HEAD(&tin->old_flows); | |
d7b64929 | 345 | INIT_LIST_HEAD(&tin->tin_list); |
bf9009bf | 346 | fq_flow_init(&tin->default_flow); |
557fc4a0 MK |
347 | } |
348 | ||
349 | static int fq_init(struct fq *fq, int flows_cnt) | |
350 | { | |
351 | int i; | |
352 | ||
353 | memset(fq, 0, sizeof(fq[0])); | |
557fc4a0 | 354 | spin_lock_init(&fq->lock); |
d7b64929 | 355 | INIT_LIST_HEAD(&fq->tin_backlog); |
557fc4a0 | 356 | fq->flows_cnt = max_t(u32, flows_cnt, 1); |
557fc4a0 MK |
357 | fq->quantum = 300; |
358 | fq->limit = 8192; | |
097b065b | 359 | fq->memory_limit = 16 << 20; /* 16 MBytes */ |
557fc4a0 | 360 | |
71e67c3b | 361 | fq->flows = kvcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL); |
557fc4a0 MK |
362 | if (!fq->flows) |
363 | return -ENOMEM; | |
364 | ||
2b8bf3d6 | 365 | fq->flows_bitmap = bitmap_zalloc(fq->flows_cnt, GFP_KERNEL); |
d7b64929 FF |
366 | if (!fq->flows_bitmap) { |
367 | kvfree(fq->flows); | |
368 | fq->flows = NULL; | |
369 | return -ENOMEM; | |
370 | } | |
371 | ||
557fc4a0 MK |
372 | for (i = 0; i < fq->flows_cnt; i++) |
373 | fq_flow_init(&fq->flows[i]); | |
374 | ||
375 | return 0; | |
376 | } | |
377 | ||
378 | static void fq_reset(struct fq *fq, | |
379 | fq_skb_free_t free_func) | |
380 | { | |
381 | int i; | |
382 | ||
383 | for (i = 0; i < fq->flows_cnt; i++) | |
384 | fq_flow_reset(fq, &fq->flows[i], free_func); | |
385 | ||
71e67c3b | 386 | kvfree(fq->flows); |
557fc4a0 | 387 | fq->flows = NULL; |
d7b64929 | 388 | |
2b8bf3d6 | 389 | bitmap_free(fq->flows_bitmap); |
d7b64929 | 390 | fq->flows_bitmap = NULL; |
557fc4a0 MK |
391 | } |
392 | ||
393 | #endif |