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 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 static void 118 __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats, 119 struct gnet_stats_basic_cpu __percpu *cpu) 120 { 121 int i; 122 123 for_each_possible_cpu(i) { 124 struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i); 125 unsigned int start; 126 u64 bytes, packets; 127 128 do { 129 start = u64_stats_fetch_begin_irq(&bcpu->syncp); 130 bytes = bcpu->bstats.bytes; 131 packets = bcpu->bstats.packets; 132 } while (u64_stats_fetch_retry_irq(&bcpu->syncp, start)); 133 134 bstats->bytes += bytes; 135 bstats->packets += packets; 136 } 137 } 138 139 void 140 __gnet_stats_copy_basic(const seqcount_t *running, 141 struct gnet_stats_basic_packed *bstats, 142 struct gnet_stats_basic_cpu __percpu *cpu, 143 struct gnet_stats_basic_packed *b) 144 { 145 unsigned int seq; 146 147 if (cpu) { 148 __gnet_stats_copy_basic_cpu(bstats, cpu); 149 return; 150 } 151 do { 152 if (running) 153 seq = read_seqcount_begin(running); 154 bstats->bytes = b->bytes; 155 bstats->packets = b->packets; 156 } while (running && read_seqcount_retry(running, seq)); 157 } 158 EXPORT_SYMBOL(__gnet_stats_copy_basic); 159 160 static int 161 ___gnet_stats_copy_basic(const seqcount_t *running, 162 struct gnet_dump *d, 163 struct gnet_stats_basic_cpu __percpu *cpu, 164 struct gnet_stats_basic_packed *b, 165 int type) 166 { 167 struct gnet_stats_basic_packed bstats = {0}; 168 169 __gnet_stats_copy_basic(running, &bstats, cpu, b); 170 171 if (d->compat_tc_stats && type == TCA_STATS_BASIC) { 172 d->tc_stats.bytes = bstats.bytes; 173 d->tc_stats.packets = bstats.packets; 174 } 175 176 if (d->tail) { 177 struct gnet_stats_basic sb; 178 int res; 179 180 memset(&sb, 0, sizeof(sb)); 181 sb.bytes = bstats.bytes; 182 sb.packets = bstats.packets; 183 res = gnet_stats_copy(d, type, &sb, sizeof(sb), TCA_STATS_PAD); 184 if (res < 0 || sb.packets == bstats.packets) 185 return res; 186 /* emit 64bit stats only if needed */ 187 return gnet_stats_copy(d, TCA_STATS_PKT64, &bstats.packets, 188 sizeof(bstats.packets), TCA_STATS_PAD); 189 } 190 return 0; 191 } 192 193 /** 194 * gnet_stats_copy_basic - copy basic statistics into statistic TLV 195 * @running: seqcount_t pointer 196 * @d: dumping handle 197 * @cpu: copy statistic per cpu 198 * @b: basic statistics 199 * 200 * Appends the basic statistics to the top level TLV created by 201 * gnet_stats_start_copy(). 202 * 203 * Returns 0 on success or -1 with the statistic lock released 204 * if the room in the socket buffer was not sufficient. 205 */ 206 int 207 gnet_stats_copy_basic(const seqcount_t *running, 208 struct gnet_dump *d, 209 struct gnet_stats_basic_cpu __percpu *cpu, 210 struct gnet_stats_basic_packed *b) 211 { 212 return ___gnet_stats_copy_basic(running, d, cpu, b, 213 TCA_STATS_BASIC); 214 } 215 EXPORT_SYMBOL(gnet_stats_copy_basic); 216 217 /** 218 * gnet_stats_copy_basic_hw - copy basic hw statistics into statistic TLV 219 * @running: seqcount_t pointer 220 * @d: dumping handle 221 * @cpu: copy statistic per cpu 222 * @b: basic statistics 223 * 224 * Appends the basic statistics to the top level TLV created by 225 * gnet_stats_start_copy(). 226 * 227 * Returns 0 on success or -1 with the statistic lock released 228 * if the room in the socket buffer was not sufficient. 229 */ 230 int 231 gnet_stats_copy_basic_hw(const seqcount_t *running, 232 struct gnet_dump *d, 233 struct gnet_stats_basic_cpu __percpu *cpu, 234 struct gnet_stats_basic_packed *b) 235 { 236 return ___gnet_stats_copy_basic(running, d, cpu, b, 237 TCA_STATS_BASIC_HW); 238 } 239 EXPORT_SYMBOL(gnet_stats_copy_basic_hw); 240 241 /** 242 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV 243 * @d: dumping handle 244 * @rate_est: rate estimator 245 * 246 * Appends the rate estimator statistics to the top level TLV created by 247 * gnet_stats_start_copy(). 248 * 249 * Returns 0 on success or -1 with the statistic lock released 250 * if the room in the socket buffer was not sufficient. 251 */ 252 int 253 gnet_stats_copy_rate_est(struct gnet_dump *d, 254 struct net_rate_estimator __rcu **rate_est) 255 { 256 struct gnet_stats_rate_est64 sample; 257 struct gnet_stats_rate_est est; 258 int res; 259 260 if (!gen_estimator_read(rate_est, &sample)) 261 return 0; 262 est.bps = min_t(u64, UINT_MAX, sample.bps); 263 /* we have some time before reaching 2^32 packets per second */ 264 est.pps = sample.pps; 265 266 if (d->compat_tc_stats) { 267 d->tc_stats.bps = est.bps; 268 d->tc_stats.pps = est.pps; 269 } 270 271 if (d->tail) { 272 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est), 273 TCA_STATS_PAD); 274 if (res < 0 || est.bps == sample.bps) 275 return res; 276 /* emit 64bit stats only if needed */ 277 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, &sample, 278 sizeof(sample), TCA_STATS_PAD); 279 } 280 281 return 0; 282 } 283 EXPORT_SYMBOL(gnet_stats_copy_rate_est); 284 285 static void 286 __gnet_stats_copy_queue_cpu(struct gnet_stats_queue *qstats, 287 const struct gnet_stats_queue __percpu *q) 288 { 289 int i; 290 291 for_each_possible_cpu(i) { 292 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 293 294 qstats->qlen = 0; 295 qstats->backlog += qcpu->backlog; 296 qstats->drops += qcpu->drops; 297 qstats->requeues += qcpu->requeues; 298 qstats->overlimits += qcpu->overlimits; 299 } 300 } 301 302 void __gnet_stats_copy_queue(struct gnet_stats_queue *qstats, 303 const struct gnet_stats_queue __percpu *cpu, 304 const struct gnet_stats_queue *q, 305 __u32 qlen) 306 { 307 if (cpu) { 308 __gnet_stats_copy_queue_cpu(qstats, cpu); 309 } else { 310 qstats->qlen = q->qlen; 311 qstats->backlog = q->backlog; 312 qstats->drops = q->drops; 313 qstats->requeues = q->requeues; 314 qstats->overlimits = q->overlimits; 315 } 316 317 qstats->qlen = qlen; 318 } 319 EXPORT_SYMBOL(__gnet_stats_copy_queue); 320 321 /** 322 * gnet_stats_copy_queue - copy queue statistics into statistics TLV 323 * @d: dumping handle 324 * @cpu_q: per cpu queue statistics 325 * @q: queue statistics 326 * @qlen: queue length statistics 327 * 328 * Appends the queue statistics to the top level TLV created by 329 * gnet_stats_start_copy(). Using per cpu queue statistics if 330 * they are available. 331 * 332 * Returns 0 on success or -1 with the statistic lock released 333 * if the room in the socket buffer was not sufficient. 334 */ 335 int 336 gnet_stats_copy_queue(struct gnet_dump *d, 337 struct gnet_stats_queue __percpu *cpu_q, 338 struct gnet_stats_queue *q, __u32 qlen) 339 { 340 struct gnet_stats_queue qstats = {0}; 341 342 __gnet_stats_copy_queue(&qstats, cpu_q, q, qlen); 343 344 if (d->compat_tc_stats) { 345 d->tc_stats.drops = qstats.drops; 346 d->tc_stats.qlen = qstats.qlen; 347 d->tc_stats.backlog = qstats.backlog; 348 d->tc_stats.overlimits = qstats.overlimits; 349 } 350 351 if (d->tail) 352 return gnet_stats_copy(d, TCA_STATS_QUEUE, 353 &qstats, sizeof(qstats), 354 TCA_STATS_PAD); 355 356 return 0; 357 } 358 EXPORT_SYMBOL(gnet_stats_copy_queue); 359 360 /** 361 * gnet_stats_copy_app - copy application specific statistics into statistics TLV 362 * @d: dumping handle 363 * @st: application specific statistics data 364 * @len: length of data 365 * 366 * Appends the application specific statistics to the top level TLV created by 367 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping 368 * handle is in backward compatibility mode. 369 * 370 * Returns 0 on success or -1 with the statistic lock released 371 * if the room in the socket buffer was not sufficient. 372 */ 373 int 374 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) 375 { 376 if (d->compat_xstats) { 377 d->xstats = kmemdup(st, len, GFP_ATOMIC); 378 if (!d->xstats) 379 goto err_out; 380 d->xstats_len = len; 381 } 382 383 if (d->tail) 384 return gnet_stats_copy(d, TCA_STATS_APP, st, len, 385 TCA_STATS_PAD); 386 387 return 0; 388 389 err_out: 390 if (d->lock) 391 spin_unlock_bh(d->lock); 392 d->xstats_len = 0; 393 return -1; 394 } 395 EXPORT_SYMBOL(gnet_stats_copy_app); 396 397 /** 398 * gnet_stats_finish_copy - finish dumping procedure 399 * @d: dumping handle 400 * 401 * Corrects the length of the top level TLV to include all TLVs added 402 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs 403 * if gnet_stats_start_copy_compat() was used and releases the statistics 404 * lock. 405 * 406 * Returns 0 on success or -1 with the statistic lock released 407 * if the room in the socket buffer was not sufficient. 408 */ 409 int 410 gnet_stats_finish_copy(struct gnet_dump *d) 411 { 412 if (d->tail) 413 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; 414 415 if (d->compat_tc_stats) 416 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, 417 sizeof(d->tc_stats), d->padattr) < 0) 418 return -1; 419 420 if (d->compat_xstats && d->xstats) { 421 if (gnet_stats_copy(d, d->compat_xstats, d->xstats, 422 d->xstats_len, d->padattr) < 0) 423 return -1; 424 } 425 426 if (d->lock) 427 spin_unlock_bh(d->lock); 428 kfree(d->xstats); 429 d->xstats = NULL; 430 d->xstats_len = 0; 431 return 0; 432 } 433 EXPORT_SYMBOL(gnet_stats_finish_copy); 434