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 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 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 struct gnet_stats_basic_sync __percpu *cpu, 151 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 struct gnet_stats_basic_sync __percpu *cpu, 176 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 struct gnet_stats_basic_sync *bcpu = per_cpu_ptr(cpu, i); 186 unsigned int start; 187 u64 bytes, packets; 188 189 do { 190 start = u64_stats_fetch_begin(&bcpu->syncp); 191 bytes = u64_stats_read(&bcpu->bytes); 192 packets = u64_stats_read(&bcpu->packets); 193 } while (u64_stats_fetch_retry(&bcpu->syncp, start)); 194 195 t_bytes += bytes; 196 t_packets += packets; 197 } 198 *ret_bytes = t_bytes; 199 *ret_packets = t_packets; 200 return; 201 } 202 do { 203 if (running) 204 start = u64_stats_fetch_begin(&b->syncp); 205 *ret_bytes = u64_stats_read(&b->bytes); 206 *ret_packets = u64_stats_read(&b->packets); 207 } while (running && u64_stats_fetch_retry(&b->syncp, start)); 208 } 209 210 static int 211 ___gnet_stats_copy_basic(struct gnet_dump *d, 212 struct gnet_stats_basic_sync __percpu *cpu, 213 struct gnet_stats_basic_sync *b, 214 int type, bool running) 215 { 216 u64 bstats_bytes, bstats_packets; 217 218 gnet_stats_read_basic(&bstats_bytes, &bstats_packets, cpu, b, running); 219 220 if (d->compat_tc_stats && type == TCA_STATS_BASIC) { 221 d->tc_stats.bytes = bstats_bytes; 222 d->tc_stats.packets = bstats_packets; 223 } 224 225 if (d->tail) { 226 struct gnet_stats_basic sb; 227 int res; 228 229 memset(&sb, 0, sizeof(sb)); 230 sb.bytes = bstats_bytes; 231 sb.packets = bstats_packets; 232 res = gnet_stats_copy(d, type, &sb, sizeof(sb), TCA_STATS_PAD); 233 if (res < 0 || sb.packets == bstats_packets) 234 return res; 235 /* emit 64bit stats only if needed */ 236 return gnet_stats_copy(d, TCA_STATS_PKT64, &bstats_packets, 237 sizeof(bstats_packets), TCA_STATS_PAD); 238 } 239 return 0; 240 } 241 242 /** 243 * gnet_stats_copy_basic - copy basic statistics into statistic TLV 244 * @d: dumping handle 245 * @cpu: copy statistic per cpu 246 * @b: basic statistics 247 * @running: true if @b represents a running qdisc, thus @b's 248 * internal values might change during basic reads. 249 * Only used if @cpu is NULL 250 * 251 * Context: task; must not be run from IRQ or BH contexts 252 * 253 * Appends the basic statistics to the top level TLV created by 254 * gnet_stats_start_copy(). 255 * 256 * Returns 0 on success or -1 with the statistic lock released 257 * if the room in the socket buffer was not sufficient. 258 */ 259 int 260 gnet_stats_copy_basic(struct gnet_dump *d, 261 struct gnet_stats_basic_sync __percpu *cpu, 262 struct gnet_stats_basic_sync *b, 263 bool running) 264 { 265 return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC, running); 266 } 267 EXPORT_SYMBOL(gnet_stats_copy_basic); 268 269 /** 270 * gnet_stats_copy_basic_hw - copy basic hw statistics into statistic TLV 271 * @d: dumping handle 272 * @cpu: copy statistic per cpu 273 * @b: basic statistics 274 * @running: true if @b represents a running qdisc, thus @b's 275 * internal values might change during basic reads. 276 * Only used if @cpu is NULL 277 * 278 * Context: task; must not be run from IRQ or BH contexts 279 * 280 * Appends the basic statistics to the top level TLV created by 281 * gnet_stats_start_copy(). 282 * 283 * Returns 0 on success or -1 with the statistic lock released 284 * if the room in the socket buffer was not sufficient. 285 */ 286 int 287 gnet_stats_copy_basic_hw(struct gnet_dump *d, 288 struct gnet_stats_basic_sync __percpu *cpu, 289 struct gnet_stats_basic_sync *b, 290 bool running) 291 { 292 return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC_HW, running); 293 } 294 EXPORT_SYMBOL(gnet_stats_copy_basic_hw); 295 296 /** 297 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV 298 * @d: dumping handle 299 * @rate_est: rate estimator 300 * 301 * Appends the rate estimator statistics to the top level TLV created by 302 * gnet_stats_start_copy(). 303 * 304 * Returns 0 on success or -1 with the statistic lock released 305 * if the room in the socket buffer was not sufficient. 306 */ 307 int 308 gnet_stats_copy_rate_est(struct gnet_dump *d, 309 struct net_rate_estimator __rcu **rate_est) 310 { 311 struct gnet_stats_rate_est64 sample; 312 struct gnet_stats_rate_est est; 313 int res; 314 315 if (!gen_estimator_read(rate_est, &sample)) 316 return 0; 317 est.bps = min_t(u64, UINT_MAX, sample.bps); 318 /* we have some time before reaching 2^32 packets per second */ 319 est.pps = sample.pps; 320 321 if (d->compat_tc_stats) { 322 d->tc_stats.bps = est.bps; 323 d->tc_stats.pps = est.pps; 324 } 325 326 if (d->tail) { 327 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est), 328 TCA_STATS_PAD); 329 if (res < 0 || est.bps == sample.bps) 330 return res; 331 /* emit 64bit stats only if needed */ 332 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, &sample, 333 sizeof(sample), TCA_STATS_PAD); 334 } 335 336 return 0; 337 } 338 EXPORT_SYMBOL(gnet_stats_copy_rate_est); 339 340 static void gnet_stats_add_queue_cpu(struct gnet_stats_queue *qstats, 341 const struct gnet_stats_queue __percpu *q) 342 { 343 int i; 344 345 for_each_possible_cpu(i) { 346 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 347 348 qstats->qlen += qcpu->qlen; 349 qstats->backlog += qcpu->backlog; 350 qstats->drops += qcpu->drops; 351 qstats->requeues += qcpu->requeues; 352 qstats->overlimits += qcpu->overlimits; 353 } 354 } 355 356 void gnet_stats_add_queue(struct gnet_stats_queue *qstats, 357 const struct gnet_stats_queue __percpu *cpu, 358 const struct gnet_stats_queue *q) 359 { 360 if (cpu) { 361 gnet_stats_add_queue_cpu(qstats, cpu); 362 } else { 363 qstats->qlen += q->qlen; 364 qstats->backlog += q->backlog; 365 qstats->drops += q->drops; 366 qstats->requeues += q->requeues; 367 qstats->overlimits += q->overlimits; 368 } 369 } 370 EXPORT_SYMBOL(gnet_stats_add_queue); 371 372 /** 373 * gnet_stats_copy_queue - copy queue statistics into statistics TLV 374 * @d: dumping handle 375 * @cpu_q: per cpu queue statistics 376 * @q: queue statistics 377 * @qlen: queue length statistics 378 * 379 * Appends the queue statistics to the top level TLV created by 380 * gnet_stats_start_copy(). Using per cpu queue statistics if 381 * they are available. 382 * 383 * Returns 0 on success or -1 with the statistic lock released 384 * if the room in the socket buffer was not sufficient. 385 */ 386 int 387 gnet_stats_copy_queue(struct gnet_dump *d, 388 struct gnet_stats_queue __percpu *cpu_q, 389 struct gnet_stats_queue *q, __u32 qlen) 390 { 391 struct gnet_stats_queue qstats = {0}; 392 393 gnet_stats_add_queue(&qstats, cpu_q, q); 394 qstats.qlen = qlen; 395 396 if (d->compat_tc_stats) { 397 d->tc_stats.drops = qstats.drops; 398 d->tc_stats.qlen = qstats.qlen; 399 d->tc_stats.backlog = qstats.backlog; 400 d->tc_stats.overlimits = qstats.overlimits; 401 } 402 403 if (d->tail) 404 return gnet_stats_copy(d, TCA_STATS_QUEUE, 405 &qstats, sizeof(qstats), 406 TCA_STATS_PAD); 407 408 return 0; 409 } 410 EXPORT_SYMBOL(gnet_stats_copy_queue); 411 412 /** 413 * gnet_stats_copy_app - copy application specific statistics into statistics TLV 414 * @d: dumping handle 415 * @st: application specific statistics data 416 * @len: length of data 417 * 418 * Appends the application specific statistics to the top level TLV created by 419 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping 420 * handle is in backward compatibility mode. 421 * 422 * Returns 0 on success or -1 with the statistic lock released 423 * if the room in the socket buffer was not sufficient. 424 */ 425 int 426 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) 427 { 428 if (d->compat_xstats) { 429 d->xstats = kmemdup(st, len, GFP_ATOMIC); 430 if (!d->xstats) 431 goto err_out; 432 d->xstats_len = len; 433 } 434 435 if (d->tail) 436 return gnet_stats_copy(d, TCA_STATS_APP, st, len, 437 TCA_STATS_PAD); 438 439 return 0; 440 441 err_out: 442 if (d->lock) 443 spin_unlock_bh(d->lock); 444 d->xstats_len = 0; 445 return -1; 446 } 447 EXPORT_SYMBOL(gnet_stats_copy_app); 448 449 /** 450 * gnet_stats_finish_copy - finish dumping procedure 451 * @d: dumping handle 452 * 453 * Corrects the length of the top level TLV to include all TLVs added 454 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs 455 * if gnet_stats_start_copy_compat() was used and releases the statistics 456 * lock. 457 * 458 * Returns 0 on success or -1 with the statistic lock released 459 * if the room in the socket buffer was not sufficient. 460 */ 461 int 462 gnet_stats_finish_copy(struct gnet_dump *d) 463 { 464 if (d->tail) 465 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; 466 467 if (d->compat_tc_stats) 468 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, 469 sizeof(d->tc_stats), d->padattr) < 0) 470 return -1; 471 472 if (d->compat_xstats && d->xstats) { 473 if (gnet_stats_copy(d, d->compat_xstats, d->xstats, 474 d->xstats_len, d->padattr) < 0) 475 return -1; 476 } 477 478 if (d->lock) 479 spin_unlock_bh(d->lock); 480 kfree(d->xstats); 481 d->xstats = NULL; 482 d->xstats_len = 0; 483 return 0; 484 } 485 EXPORT_SYMBOL(gnet_stats_finish_copy); 486