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| 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
|---|---|
| 2 | /* |
| 3 | * Copyright (c) 2016 Qualcomm Atheros, Inc |
| 4 | * |
| 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 | |
| 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; |
| 20 | int idx; |
| 21 | |
| 22 | tin->backlog_bytes -= bytes; |
| 23 | tin->backlog_packets -= packets; |
| 24 | flow->backlog -= bytes; |
| 25 | fq->backlog -= packets; |
| 26 | fq->memory_usage -= truesize; |
| 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); |
| 38 | } |
| 39 | |
| 40 | static void fq_adjust_removal(struct fq *fq, |
| 41 | struct fq_flow *flow, |
| 42 | struct sk_buff *skb) |
| 43 | { |
| 44 | __fq_adjust_removal(fq, flow, 1, skb->len, skb->truesize); |
| 45 | } |
| 46 | |
| 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); |
| 59 | |
| 60 | return skb; |
| 61 | } |
| 62 | |
| 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); |
| 86 | |
| 87 | return packets; |
| 88 | } |
| 89 | |
| 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 | |
| 137 | static u32 fq_flow_idx(struct fq *fq, struct sk_buff *skb) |
| 138 | { |
| 139 | u32 hash = skb_get_hash(skb); |
| 140 | |
| 141 | return reciprocal_scale(hash, fq->flows_cnt); |
| 142 | } |
| 143 | |
| 144 | static struct fq_flow *fq_flow_classify(struct fq *fq, |
| 145 | struct fq_tin *tin, u32 idx, |
| 146 | struct sk_buff *skb) |
| 147 | { |
| 148 | struct fq_flow *flow; |
| 149 | |
| 150 | lockdep_assert_held(&fq->lock); |
| 151 | |
| 152 | flow = &fq->flows[idx]; |
| 153 | if (flow->tin && flow->tin != tin) { |
| 154 | flow = &tin->default_flow; |
| 155 | tin->collisions++; |
| 156 | fq->collisions++; |
| 157 | } |
| 158 | |
| 159 | if (!flow->tin) |
| 160 | tin->flows++; |
| 161 | |
| 162 | return flow; |
| 163 | } |
| 164 | |
| 165 | static struct fq_flow *fq_find_fattest_flow(struct fq *fq) |
| 166 | { |
| 167 | struct fq_tin *tin; |
| 168 | struct fq_flow *flow = NULL; |
| 169 | u32 len = 0; |
| 170 | int i; |
| 171 | |
| 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; |
| 175 | |
| 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; |
| 186 | |
| 187 | if (cur_len <= len) |
| 188 | continue; |
| 189 | |
| 190 | flow = &tin->default_flow; |
| 191 | len = cur_len; |
| 192 | } |
| 193 | |
| 194 | return flow; |
| 195 | } |
| 196 | |
| 197 | static void fq_tin_enqueue(struct fq *fq, |
| 198 | struct fq_tin *tin, u32 idx, |
| 199 | struct sk_buff *skb, |
| 200 | fq_skb_free_t free_func) |
| 201 | { |
| 202 | struct fq_flow *flow; |
| 203 | struct sk_buff *next; |
| 204 | bool oom; |
| 205 | |
| 206 | lockdep_assert_held(&fq->lock); |
| 207 | |
| 208 | flow = fq_flow_classify(fq, tin, idx, skb); |
| 209 | |
| 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 | |
| 217 | flow->tin = tin; |
| 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 | } |
| 227 | |
| 228 | if (list_empty(&flow->flowchain)) { |
| 229 | flow->deficit = fq->quantum; |
| 230 | list_add_tail(&flow->flowchain, |
| 231 | &tin->new_flows); |
| 232 | } |
| 233 | |
| 234 | oom = (fq->memory_usage > fq->memory_limit); |
| 235 | while (fq->backlog > fq->limit || oom) { |
| 236 | flow = fq_find_fattest_flow(fq); |
| 237 | if (!flow) |
| 238 | return; |
| 239 | |
| 240 | if (!fq_flow_drop(fq, flow, free_func)) |
| 241 | return; |
| 242 | |
| 243 | flow->tin->overlimit++; |
| 244 | fq->overlimit++; |
| 245 | if (oom) { |
| 246 | fq->overmemory++; |
| 247 | oom = (fq->memory_usage > fq->memory_limit); |
| 248 | } |
| 249 | } |
| 250 | } |
| 251 | |
| 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 | } |
| 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 | |
| 289 | static void fq_flow_reset(struct fq *fq, |
| 290 | struct fq_flow *flow, |
| 291 | fq_skb_free_t free_func) |
| 292 | { |
| 293 | struct fq_tin *tin = flow->tin; |
| 294 | struct sk_buff *skb; |
| 295 | |
| 296 | while ((skb = fq_flow_dequeue(fq, flow))) |
| 297 | free_func(fq, tin, flow, skb); |
| 298 | |
| 299 | if (!list_empty(&flow->flowchain)) { |
| 300 | list_del_init(&flow->flowchain); |
| 301 | if (list_empty(&tin->new_flows) && |
| 302 | list_empty(&tin->old_flows)) |
| 303 | list_del_init(&tin->tin_list); |
| 304 | } |
| 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 | |
| 330 | WARN_ON_ONCE(!list_empty(&tin->tin_list)); |
| 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); |
| 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); |
| 345 | INIT_LIST_HEAD(&tin->tin_list); |
| 346 | fq_flow_init(&tin->default_flow); |
| 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])); |
| 354 | spin_lock_init(&fq->lock); |
| 355 | INIT_LIST_HEAD(&fq->tin_backlog); |
| 356 | fq->flows_cnt = max_t(u32, flows_cnt, 1); |
| 357 | fq->quantum = 300; |
| 358 | fq->limit = 8192; |
| 359 | fq->memory_limit = 16 << 20; /* 16 MBytes */ |
| 360 | |
| 361 | fq->flows = kvcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL); |
| 362 | if (!fq->flows) |
| 363 | return -ENOMEM; |
| 364 | |
| 365 | fq->flows_bitmap = bitmap_zalloc(fq->flows_cnt, GFP_KERNEL); |
| 366 | if (!fq->flows_bitmap) { |
| 367 | kvfree(fq->flows); |
| 368 | fq->flows = NULL; |
| 369 | return -ENOMEM; |
| 370 | } |
| 371 | |
| 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 | |
| 386 | kvfree(fq->flows); |
| 387 | fq->flows = NULL; |
| 388 | |
| 389 | bitmap_free(fq->flows_bitmap); |
| 390 | fq->flows_bitmap = NULL; |
| 391 | } |
| 392 | |
| 393 | #endif |
| 394 |
Warning: This file is not a C or C++ file. It does not have highlighting.