1 /* 2 * net/core/gen_stats.c 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Thomas Graf <tgraf@suug.ch> 10 * Jamal Hadi Salim 11 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 12 * 13 * See Documentation/networking/gen_stats.txt 14 */ 15 16 #include <linux/types.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/interrupt.h> 20 #include <linux/socket.h> 21 #include <linux/rtnetlink.h> 22 #include <linux/gen_stats.h> 23 #include <net/netlink.h> 24 #include <net/gen_stats.h> 25 26 27 static inline int 28 gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size, int padattr) 29 { 30 if (nla_put_64bit(d->skb, type, size, buf, padattr)) 31 goto nla_put_failure; 32 return 0; 33 34 nla_put_failure: 35 if (d->lock) 36 spin_unlock_bh(d->lock); 37 kfree(d->xstats); 38 d->xstats = NULL; 39 d->xstats_len = 0; 40 return -1; 41 } 42 43 /** 44 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode 45 * @skb: socket buffer to put statistics TLVs into 46 * @type: TLV type for top level statistic TLV 47 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV 48 * @xstats_type: TLV type for backward compatibility xstats TLV 49 * @lock: statistics lock 50 * @d: dumping handle 51 * @padattr: padding attribute 52 * 53 * Initializes the dumping handle, grabs the statistic lock and appends 54 * an empty TLV header to the socket buffer for use a container for all 55 * other statistic TLVS. 56 * 57 * The dumping handle is marked to be in backward compatibility mode telling 58 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats. 59 * 60 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 61 */ 62 int 63 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type, 64 int xstats_type, spinlock_t *lock, 65 struct gnet_dump *d, int padattr) 66 __acquires(lock) 67 { 68 memset(d, 0, sizeof(*d)); 69 70 if (type) 71 d->tail = (struct nlattr *)skb_tail_pointer(skb); 72 d->skb = skb; 73 d->compat_tc_stats = tc_stats_type; 74 d->compat_xstats = xstats_type; 75 d->padattr = padattr; 76 if (lock) { 77 d->lock = lock; 78 spin_lock_bh(lock); 79 } 80 if (d->tail) { 81 int ret = gnet_stats_copy(d, type, NULL, 0, padattr); 82 83 /* The initial attribute added in gnet_stats_copy() may be 84 * preceded by a padding attribute, in which case d->tail will 85 * end up pointing at the padding instead of the real attribute. 86 * Fix this so gnet_stats_finish_copy() adjusts the length of 87 * the right attribute. 88 */ 89 if (ret == 0 && d->tail->nla_type == padattr) 90 d->tail = (struct nlattr *)((char *)d->tail + 91 NLA_ALIGN(d->tail->nla_len)); 92 return ret; 93 } 94 95 return 0; 96 } 97 EXPORT_SYMBOL(gnet_stats_start_copy_compat); 98 99 /** 100 * gnet_stats_start_copy - start dumping procedure in compatibility mode 101 * @skb: socket buffer to put statistics TLVs into 102 * @type: TLV type for top level statistic TLV 103 * @lock: statistics lock 104 * @d: dumping handle 105 * @padattr: padding attribute 106 * 107 * Initializes the dumping handle, grabs the statistic lock and appends 108 * an empty TLV header to the socket buffer for use a container for all 109 * other statistic TLVS. 110 * 111 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 112 */ 113 int 114 gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock, 115 struct gnet_dump *d, int padattr) 116 { 117 return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d, padattr); 118 } 119 EXPORT_SYMBOL(gnet_stats_start_copy); 120 121 static void 122 __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats, 123 struct gnet_stats_basic_cpu __percpu *cpu) 124 { 125 int i; 126 127 for_each_possible_cpu(i) { 128 struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i); 129 unsigned int start; 130 u64 bytes; 131 u32 packets; 132 133 do { 134 start = u64_stats_fetch_begin_irq(&bcpu->syncp); 135 bytes = bcpu->bstats.bytes; 136 packets = bcpu->bstats.packets; 137 } while (u64_stats_fetch_retry_irq(&bcpu->syncp, start)); 138 139 bstats->bytes += bytes; 140 bstats->packets += packets; 141 } 142 } 143 144 void 145 __gnet_stats_copy_basic(const seqcount_t *running, 146 struct gnet_stats_basic_packed *bstats, 147 struct gnet_stats_basic_cpu __percpu *cpu, 148 struct gnet_stats_basic_packed *b) 149 { 150 unsigned int seq; 151 152 if (cpu) { 153 __gnet_stats_copy_basic_cpu(bstats, cpu); 154 return; 155 } 156 do { 157 if (running) 158 seq = read_seqcount_begin(running); 159 bstats->bytes = b->bytes; 160 bstats->packets = b->packets; 161 } while (running && read_seqcount_retry(running, seq)); 162 } 163 EXPORT_SYMBOL(__gnet_stats_copy_basic); 164 165 /** 166 * gnet_stats_copy_basic - copy basic statistics into statistic TLV 167 * @running: seqcount_t pointer 168 * @d: dumping handle 169 * @cpu: copy statistic per cpu 170 * @b: basic statistics 171 * 172 * Appends the basic statistics to the top level TLV created by 173 * gnet_stats_start_copy(). 174 * 175 * Returns 0 on success or -1 with the statistic lock released 176 * if the room in the socket buffer was not sufficient. 177 */ 178 int 179 gnet_stats_copy_basic(const seqcount_t *running, 180 struct gnet_dump *d, 181 struct gnet_stats_basic_cpu __percpu *cpu, 182 struct gnet_stats_basic_packed *b) 183 { 184 struct gnet_stats_basic_packed bstats = {0}; 185 186 __gnet_stats_copy_basic(running, &bstats, cpu, b); 187 188 if (d->compat_tc_stats) { 189 d->tc_stats.bytes = bstats.bytes; 190 d->tc_stats.packets = bstats.packets; 191 } 192 193 if (d->tail) { 194 struct gnet_stats_basic sb; 195 196 memset(&sb, 0, sizeof(sb)); 197 sb.bytes = bstats.bytes; 198 sb.packets = bstats.packets; 199 return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb), 200 TCA_STATS_PAD); 201 } 202 return 0; 203 } 204 EXPORT_SYMBOL(gnet_stats_copy_basic); 205 206 /** 207 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV 208 * @d: dumping handle 209 * @rate_est: rate estimator 210 * 211 * Appends the rate estimator statistics to the top level TLV created by 212 * gnet_stats_start_copy(). 213 * 214 * Returns 0 on success or -1 with the statistic lock released 215 * if the room in the socket buffer was not sufficient. 216 */ 217 int 218 gnet_stats_copy_rate_est(struct gnet_dump *d, 219 struct net_rate_estimator __rcu **rate_est) 220 { 221 struct gnet_stats_rate_est64 sample; 222 struct gnet_stats_rate_est est; 223 int res; 224 225 if (!gen_estimator_read(rate_est, &sample)) 226 return 0; 227 est.bps = min_t(u64, UINT_MAX, sample.bps); 228 /* we have some time before reaching 2^32 packets per second */ 229 est.pps = sample.pps; 230 231 if (d->compat_tc_stats) { 232 d->tc_stats.bps = est.bps; 233 d->tc_stats.pps = est.pps; 234 } 235 236 if (d->tail) { 237 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est), 238 TCA_STATS_PAD); 239 if (res < 0 || est.bps == sample.bps) 240 return res; 241 /* emit 64bit stats only if needed */ 242 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, &sample, 243 sizeof(sample), TCA_STATS_PAD); 244 } 245 246 return 0; 247 } 248 EXPORT_SYMBOL(gnet_stats_copy_rate_est); 249 250 static void 251 __gnet_stats_copy_queue_cpu(struct gnet_stats_queue *qstats, 252 const struct gnet_stats_queue __percpu *q) 253 { 254 int i; 255 256 for_each_possible_cpu(i) { 257 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 258 259 qstats->qlen = 0; 260 qstats->backlog += qcpu->backlog; 261 qstats->drops += qcpu->drops; 262 qstats->requeues += qcpu->requeues; 263 qstats->overlimits += qcpu->overlimits; 264 } 265 } 266 267 void __gnet_stats_copy_queue(struct gnet_stats_queue *qstats, 268 const struct gnet_stats_queue __percpu *cpu, 269 const struct gnet_stats_queue *q, 270 __u32 qlen) 271 { 272 if (cpu) { 273 __gnet_stats_copy_queue_cpu(qstats, cpu); 274 } else { 275 qstats->qlen = q->qlen; 276 qstats->backlog = q->backlog; 277 qstats->drops = q->drops; 278 qstats->requeues = q->requeues; 279 qstats->overlimits = q->overlimits; 280 } 281 282 qstats->qlen = qlen; 283 } 284 EXPORT_SYMBOL(__gnet_stats_copy_queue); 285 286 /** 287 * gnet_stats_copy_queue - copy queue statistics into statistics TLV 288 * @d: dumping handle 289 * @cpu_q: per cpu queue statistics 290 * @q: queue statistics 291 * @qlen: queue length statistics 292 * 293 * Appends the queue statistics to the top level TLV created by 294 * gnet_stats_start_copy(). Using per cpu queue statistics if 295 * they are available. 296 * 297 * Returns 0 on success or -1 with the statistic lock released 298 * if the room in the socket buffer was not sufficient. 299 */ 300 int 301 gnet_stats_copy_queue(struct gnet_dump *d, 302 struct gnet_stats_queue __percpu *cpu_q, 303 struct gnet_stats_queue *q, __u32 qlen) 304 { 305 struct gnet_stats_queue qstats = {0}; 306 307 __gnet_stats_copy_queue(&qstats, cpu_q, q, qlen); 308 309 if (d->compat_tc_stats) { 310 d->tc_stats.drops = qstats.drops; 311 d->tc_stats.qlen = qstats.qlen; 312 d->tc_stats.backlog = qstats.backlog; 313 d->tc_stats.overlimits = qstats.overlimits; 314 } 315 316 if (d->tail) 317 return gnet_stats_copy(d, TCA_STATS_QUEUE, 318 &qstats, sizeof(qstats), 319 TCA_STATS_PAD); 320 321 return 0; 322 } 323 EXPORT_SYMBOL(gnet_stats_copy_queue); 324 325 /** 326 * gnet_stats_copy_app - copy application specific statistics into statistics TLV 327 * @d: dumping handle 328 * @st: application specific statistics data 329 * @len: length of data 330 * 331 * Appends the application specific statistics to the top level TLV created by 332 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping 333 * handle is in backward compatibility mode. 334 * 335 * Returns 0 on success or -1 with the statistic lock released 336 * if the room in the socket buffer was not sufficient. 337 */ 338 int 339 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) 340 { 341 if (d->compat_xstats) { 342 d->xstats = kmemdup(st, len, GFP_ATOMIC); 343 if (!d->xstats) 344 goto err_out; 345 d->xstats_len = len; 346 } 347 348 if (d->tail) 349 return gnet_stats_copy(d, TCA_STATS_APP, st, len, 350 TCA_STATS_PAD); 351 352 return 0; 353 354 err_out: 355 if (d->lock) 356 spin_unlock_bh(d->lock); 357 d->xstats_len = 0; 358 return -1; 359 } 360 EXPORT_SYMBOL(gnet_stats_copy_app); 361 362 /** 363 * gnet_stats_finish_copy - finish dumping procedure 364 * @d: dumping handle 365 * 366 * Corrects the length of the top level TLV to include all TLVs added 367 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs 368 * if gnet_stats_start_copy_compat() was used and releases the statistics 369 * lock. 370 * 371 * Returns 0 on success or -1 with the statistic lock released 372 * if the room in the socket buffer was not sufficient. 373 */ 374 int 375 gnet_stats_finish_copy(struct gnet_dump *d) 376 { 377 if (d->tail) 378 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; 379 380 if (d->compat_tc_stats) 381 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, 382 sizeof(d->tc_stats), d->padattr) < 0) 383 return -1; 384 385 if (d->compat_xstats && d->xstats) { 386 if (gnet_stats_copy(d, d->compat_xstats, d->xstats, 387 d->xstats_len, d->padattr) < 0) 388 return -1; 389 } 390 391 if (d->lock) 392 spin_unlock_bh(d->lock); 393 kfree(d->xstats); 394 d->xstats = NULL; 395 d->xstats_len = 0; 396 return 0; 397 } 398 EXPORT_SYMBOL(gnet_stats_finish_copy); 399