1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * net/core/gen_stats.c 4 * 5 * Authors: Thomas Graf <tgraf@suug.ch> 6 * Jamal Hadi Salim 7 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 8 * 9 * See Documentation/networking/gen_stats.rst 10 */ 11 12 #include <linux/types.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/interrupt.h> 16 #include <linux/socket.h> 17 #include <linux/rtnetlink.h> 18 #include <linux/gen_stats.h> 19 #include <net/netlink.h> 20 #include <net/gen_stats.h> 21 #include <net/sch_generic.h> 22 23 static inline int 24 gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size, int padattr) 25 { 26 if (nla_put_64bit(d->skb, type, size, buf, padattr)) 27 goto nla_put_failure; 28 return 0; 29 30 nla_put_failure: 31 if (d->lock) 32 spin_unlock_bh(d->lock); 33 kfree(d->xstats); 34 d->xstats = NULL; 35 d->xstats_len = 0; 36 return -1; 37 } 38 39 /** 40 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode 41 * @skb: socket buffer to put statistics TLVs into 42 * @type: TLV type for top level statistic TLV 43 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV 44 * @xstats_type: TLV type for backward compatibility xstats TLV 45 * @lock: statistics lock 46 * @d: dumping handle 47 * @padattr: padding attribute 48 * 49 * Initializes the dumping handle, grabs the statistic lock and appends 50 * an empty TLV header to the socket buffer for use a container for all 51 * other statistic TLVS. 52 * 53 * The dumping handle is marked to be in backward compatibility mode telling 54 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats. 55 * 56 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 57 */ 58 int 59 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type, 60 int xstats_type, spinlock_t *lock, 61 struct gnet_dump *d, int padattr) 62 __acquires(lock) 63 { 64 memset(d, 0, sizeof(*d)); 65 66 if (type) 67 d->tail = (struct nlattr *)skb_tail_pointer(skb); 68 d->skb = skb; 69 d->compat_tc_stats = tc_stats_type; 70 d->compat_xstats = xstats_type; 71 d->padattr = padattr; 72 if (lock) { 73 d->lock = lock; 74 spin_lock_bh(lock); 75 } 76 if (d->tail) { 77 int ret = gnet_stats_copy(d, type, NULL, 0, padattr); 78 79 /* The initial attribute added in gnet_stats_copy() may be 80 * preceded by a padding attribute, in which case d->tail will 81 * end up pointing at the padding instead of the real attribute. 82 * Fix this so gnet_stats_finish_copy() adjusts the length of 83 * the right attribute. 84 */ 85 if (ret == 0 && d->tail->nla_type == padattr) 86 d->tail = (struct nlattr *)((char *)d->tail + 87 NLA_ALIGN(d->tail->nla_len)); 88 return ret; 89 } 90 91 return 0; 92 } 93 EXPORT_SYMBOL(gnet_stats_start_copy_compat); 94 95 /** 96 * gnet_stats_start_copy - start dumping procedure in compatibility mode 97 * @skb: socket buffer to put statistics TLVs into 98 * @type: TLV type for top level statistic TLV 99 * @lock: statistics lock 100 * @d: dumping handle 101 * @padattr: padding attribute 102 * 103 * Initializes the dumping handle, grabs the statistic lock and appends 104 * an empty TLV header to the socket buffer for use a container for all 105 * other statistic TLVS. 106 * 107 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 108 */ 109 int 110 gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock, 111 struct gnet_dump *d, int padattr) 112 { 113 return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d, padattr); 114 } 115 EXPORT_SYMBOL(gnet_stats_start_copy); 116 117 /* Must not be inlined, due to u64_stats seqcount_t lockdep key */ 118 void gnet_stats_basic_sync_init(struct gnet_stats_basic_sync *b) 119 { 120 u64_stats_set(&b->bytes, 0); 121 u64_stats_set(&b->packets, 0); 122 u64_stats_init(&b->syncp); 123 } 124 EXPORT_SYMBOL(gnet_stats_basic_sync_init); 125 126 static void gnet_stats_add_basic_cpu(struct gnet_stats_basic_sync *bstats, 127 const struct gnet_stats_basic_sync __percpu *cpu) 128 { 129 u64 t_bytes = 0, t_packets = 0; 130 int i; 131 132 for_each_possible_cpu(i) { 133 const struct gnet_stats_basic_sync *bcpu = per_cpu_ptr(cpu, i); 134 unsigned int start; 135 u64 bytes, packets; 136 137 do { 138 start = u64_stats_fetch_begin(&bcpu->syncp); 139 bytes = u64_stats_read(&bcpu->bytes); 140 packets = u64_stats_read(&bcpu->packets); 141 } while (u64_stats_fetch_retry(&bcpu->syncp, start)); 142 143 t_bytes += bytes; 144 t_packets += packets; 145 } 146 _bstats_update(bstats, t_bytes, t_packets); 147 } 148 149 void gnet_stats_add_basic(struct gnet_stats_basic_sync *bstats, 150 const struct gnet_stats_basic_sync __percpu *cpu, 151 const struct gnet_stats_basic_sync *b, bool running) 152 { 153 unsigned int start; 154 u64 bytes = 0; 155 u64 packets = 0; 156 157 WARN_ON_ONCE((cpu || running) && in_hardirq()); 158 159 if (cpu) { 160 gnet_stats_add_basic_cpu(bstats, cpu); 161 return; 162 } 163 do { 164 if (running) 165 start = u64_stats_fetch_begin(&b->syncp); 166 bytes = u64_stats_read(&b->bytes); 167 packets = u64_stats_read(&b->packets); 168 } while (running && u64_stats_fetch_retry(&b->syncp, start)); 169 170 _bstats_update(bstats, bytes, packets); 171 } 172 EXPORT_SYMBOL(gnet_stats_add_basic); 173 174 static void gnet_stats_read_basic(u64 *ret_bytes, u64 *ret_packets, 175 const struct gnet_stats_basic_sync __percpu *cpu, 176 const struct gnet_stats_basic_sync *b, bool running) 177 { 178 unsigned int start; 179 180 if (cpu) { 181 u64 t_bytes = 0, t_packets = 0; 182 int i; 183 184 for_each_possible_cpu(i) { 185 const struct gnet_stats_basic_sync *bcpu = per_cpu_ptr(cpu, i); 186 u64 bytes, packets; 187 188 do { 189 start = u64_stats_fetch_begin(&bcpu->syncp); 190 bytes = u64_stats_read(&bcpu->bytes); 191 packets = u64_stats_read(&bcpu->packets); 192 } while (u64_stats_fetch_retry(&bcpu->syncp, start)); 193 194 t_bytes += bytes; 195 t_packets += packets; 196 } 197 *ret_bytes = t_bytes; 198 *ret_packets = t_packets; 199 return; 200 } 201 do { 202 if (running) 203 start = u64_stats_fetch_begin(&b->syncp); 204 *ret_bytes = u64_stats_read(&b->bytes); 205 *ret_packets = u64_stats_read(&b->packets); 206 } while (running && u64_stats_fetch_retry(&b->syncp, start)); 207 } 208 209 static int 210 ___gnet_stats_copy_basic(struct gnet_dump *d, 211 const struct gnet_stats_basic_sync __percpu *cpu, 212 const struct gnet_stats_basic_sync *b, 213 int type, bool running) 214 { 215 u64 bstats_bytes, bstats_packets; 216 217 gnet_stats_read_basic(&bstats_bytes, &bstats_packets, cpu, b, running); 218 219 if (d->compat_tc_stats && type == TCA_STATS_BASIC) { 220 d->tc_stats.bytes = bstats_bytes; 221 d->tc_stats.packets = bstats_packets; 222 } 223 224 if (d->tail) { 225 struct gnet_stats_basic sb; 226 int res; 227 228 memset(&sb, 0, sizeof(sb)); 229 sb.bytes = bstats_bytes; 230 sb.packets = bstats_packets; 231 res = gnet_stats_copy(d, type, &sb, sizeof(sb), TCA_STATS_PAD); 232 if (res < 0 || sb.packets == bstats_packets) 233 return res; 234 /* emit 64bit stats only if needed */ 235 return gnet_stats_copy(d, TCA_STATS_PKT64, &bstats_packets, 236 sizeof(bstats_packets), TCA_STATS_PAD); 237 } 238 return 0; 239 } 240 241 /** 242 * gnet_stats_copy_basic - copy basic statistics into statistic TLV 243 * @d: dumping handle 244 * @cpu: copy statistic per cpu 245 * @b: basic statistics 246 * @running: true if @b represents a running qdisc, thus @b's 247 * internal values might change during basic reads. 248 * Only used if @cpu is NULL 249 * 250 * Context: task; must not be run from IRQ or BH contexts 251 * 252 * Appends the basic statistics to the top level TLV created by 253 * gnet_stats_start_copy(). 254 * 255 * Returns 0 on success or -1 with the statistic lock released 256 * if the room in the socket buffer was not sufficient. 257 */ 258 int 259 gnet_stats_copy_basic(struct gnet_dump *d, 260 const struct gnet_stats_basic_sync __percpu *cpu, 261 const struct gnet_stats_basic_sync *b, 262 bool running) 263 { 264 return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC, running); 265 } 266 EXPORT_SYMBOL(gnet_stats_copy_basic); 267 268 /** 269 * gnet_stats_copy_basic_hw - copy basic hw statistics into statistic TLV 270 * @d: dumping handle 271 * @cpu: copy statistic per cpu 272 * @b: basic statistics 273 * @running: true if @b represents a running qdisc, thus @b's 274 * internal values might change during basic reads. 275 * Only used if @cpu is NULL 276 * 277 * Context: task; must not be run from IRQ or BH contexts 278 * 279 * Appends the basic statistics to the top level TLV created by 280 * gnet_stats_start_copy(). 281 * 282 * Returns 0 on success or -1 with the statistic lock released 283 * if the room in the socket buffer was not sufficient. 284 */ 285 int 286 gnet_stats_copy_basic_hw(struct gnet_dump *d, 287 const struct gnet_stats_basic_sync __percpu *cpu, 288 const struct gnet_stats_basic_sync *b, 289 bool running) 290 { 291 return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC_HW, running); 292 } 293 EXPORT_SYMBOL(gnet_stats_copy_basic_hw); 294 295 /** 296 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV 297 * @d: dumping handle 298 * @rate_est: rate estimator 299 * 300 * Appends the rate estimator statistics to the top level TLV created by 301 * gnet_stats_start_copy(). 302 * 303 * Returns 0 on success or -1 with the statistic lock released 304 * if the room in the socket buffer was not sufficient. 305 */ 306 int 307 gnet_stats_copy_rate_est(struct gnet_dump *d, 308 struct net_rate_estimator __rcu **rate_est) 309 { 310 struct gnet_stats_rate_est64 sample; 311 struct gnet_stats_rate_est est; 312 int res; 313 314 if (!gen_estimator_read(rate_est, &sample)) 315 return 0; 316 est.bps = min_t(u64, UINT_MAX, sample.bps); 317 /* we have some time before reaching 2^32 packets per second */ 318 est.pps = sample.pps; 319 320 if (d->compat_tc_stats) { 321 d->tc_stats.bps = est.bps; 322 d->tc_stats.pps = est.pps; 323 } 324 325 if (d->tail) { 326 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est), 327 TCA_STATS_PAD); 328 if (res < 0 || est.bps == sample.bps) 329 return res; 330 /* emit 64bit stats only if needed */ 331 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, &sample, 332 sizeof(sample), TCA_STATS_PAD); 333 } 334 335 return 0; 336 } 337 EXPORT_SYMBOL(gnet_stats_copy_rate_est); 338 339 static void gnet_stats_add_queue_cpu(struct gnet_stats_queue *qstats, 340 const struct gnet_stats_queue __percpu *q) 341 { 342 int i; 343 344 for_each_possible_cpu(i) { 345 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 346 347 qstats->qlen += READ_ONCE(qcpu->qlen); 348 qstats->backlog += READ_ONCE(qcpu->backlog); 349 qstats->drops += READ_ONCE(qcpu->drops); 350 qstats->requeues += READ_ONCE(qcpu->requeues); 351 qstats->overlimits += READ_ONCE(qcpu->overlimits); 352 } 353 } 354 355 void gnet_stats_add_queue(struct gnet_stats_queue *qstats, 356 const struct gnet_stats_queue __percpu *cpu, 357 const struct gnet_stats_queue *q) 358 { 359 if (cpu) { 360 gnet_stats_add_queue_cpu(qstats, cpu); 361 } else { 362 qstats->qlen += READ_ONCE(q->qlen); 363 qstats->backlog += READ_ONCE(q->backlog); 364 qstats->drops += READ_ONCE(q->drops); 365 qstats->requeues += READ_ONCE(q->requeues); 366 qstats->overlimits += READ_ONCE(q->overlimits); 367 } 368 } 369 EXPORT_SYMBOL(gnet_stats_add_queue); 370 371 /** 372 * gnet_stats_copy_queue - copy queue statistics into statistics TLV 373 * @d: dumping handle 374 * @cpu_q: per cpu queue statistics 375 * @q: queue statistics 376 * @qlen: queue length statistics 377 * 378 * Appends the queue statistics to the top level TLV created by 379 * gnet_stats_start_copy(). Using per cpu queue statistics if 380 * they are available. 381 * 382 * Returns 0 on success or -1 with the statistic lock released 383 * if the room in the socket buffer was not sufficient. 384 */ 385 int 386 gnet_stats_copy_queue(struct gnet_dump *d, 387 const struct gnet_stats_queue __percpu *cpu_q, 388 const struct gnet_stats_queue *q, __u32 qlen) 389 { 390 struct gnet_stats_queue qstats = {0}; 391 392 gnet_stats_add_queue(&qstats, cpu_q, q); 393 qstats.qlen = qlen; 394 395 if (d->compat_tc_stats) { 396 d->tc_stats.drops = qstats.drops; 397 d->tc_stats.qlen = qstats.qlen; 398 d->tc_stats.backlog = qstats.backlog; 399 d->tc_stats.overlimits = qstats.overlimits; 400 } 401 402 if (d->tail) 403 return gnet_stats_copy(d, TCA_STATS_QUEUE, 404 &qstats, sizeof(qstats), 405 TCA_STATS_PAD); 406 407 return 0; 408 } 409 EXPORT_SYMBOL(gnet_stats_copy_queue); 410 411 /** 412 * gnet_stats_copy_app - copy application specific statistics into statistics TLV 413 * @d: dumping handle 414 * @st: application specific statistics data 415 * @len: length of data 416 * 417 * Appends the application specific statistics to the top level TLV created by 418 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping 419 * handle is in backward compatibility mode. 420 * 421 * Returns 0 on success or -1 with the statistic lock released 422 * if the room in the socket buffer was not sufficient. 423 */ 424 int 425 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) 426 { 427 if (d->compat_xstats) { 428 d->xstats = kmemdup(st, len, GFP_ATOMIC); 429 if (!d->xstats) 430 goto err_out; 431 d->xstats_len = len; 432 } 433 434 if (d->tail) 435 return gnet_stats_copy(d, TCA_STATS_APP, st, len, 436 TCA_STATS_PAD); 437 438 return 0; 439 440 err_out: 441 if (d->lock) 442 spin_unlock_bh(d->lock); 443 d->xstats_len = 0; 444 return -1; 445 } 446 EXPORT_SYMBOL(gnet_stats_copy_app); 447 448 /** 449 * gnet_stats_finish_copy - finish dumping procedure 450 * @d: dumping handle 451 * 452 * Corrects the length of the top level TLV to include all TLVs added 453 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs 454 * if gnet_stats_start_copy_compat() was used and releases the statistics 455 * lock. 456 * 457 * Returns 0 on success or -1 with the statistic lock released 458 * if the room in the socket buffer was not sufficient. 459 */ 460 int 461 gnet_stats_finish_copy(struct gnet_dump *d) 462 { 463 if (d->tail) 464 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; 465 466 if (d->compat_tc_stats) 467 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, 468 sizeof(d->tc_stats), d->padattr) < 0) 469 return -1; 470 471 if (d->compat_xstats && d->xstats) { 472 if (gnet_stats_copy(d, d->compat_xstats, d->xstats, 473 d->xstats_len, d->padattr) < 0) 474 return -1; 475 } 476 477 if (d->lock) 478 spin_unlock_bh(d->lock); 479 kfree(d->xstats); 480 d->xstats = NULL; 481 d->xstats_len = 0; 482 return 0; 483 } 484 EXPORT_SYMBOL(gnet_stats_finish_copy); 485