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 * 52 * Initializes the dumping handle, grabs the statistic lock and appends 53 * an empty TLV header to the socket buffer for use a container for all 54 * other statistic TLVS. 55 * 56 * The dumping handle is marked to be in backward compatibility mode telling 57 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats. 58 * 59 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 60 */ 61 int 62 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type, 63 int xstats_type, spinlock_t *lock, 64 struct gnet_dump *d, int padattr) 65 __acquires(lock) 66 { 67 memset(d, 0, sizeof(*d)); 68 69 if (type) 70 d->tail = (struct nlattr *)skb_tail_pointer(skb); 71 d->skb = skb; 72 d->compat_tc_stats = tc_stats_type; 73 d->compat_xstats = xstats_type; 74 d->padattr = padattr; 75 if (lock) { 76 d->lock = lock; 77 spin_lock_bh(lock); 78 } 79 if (d->tail) 80 return gnet_stats_copy(d, type, NULL, 0, padattr); 81 82 return 0; 83 } 84 EXPORT_SYMBOL(gnet_stats_start_copy_compat); 85 86 /** 87 * gnet_stats_start_copy - start dumping procedure in compatibility mode 88 * @skb: socket buffer to put statistics TLVs into 89 * @type: TLV type for top level statistic TLV 90 * @lock: statistics lock 91 * @d: dumping handle 92 * 93 * Initializes the dumping handle, grabs the statistic lock and appends 94 * an empty TLV header to the socket buffer for use a container for all 95 * other statistic TLVS. 96 * 97 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient. 98 */ 99 int 100 gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock, 101 struct gnet_dump *d, int padattr) 102 { 103 return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d, padattr); 104 } 105 EXPORT_SYMBOL(gnet_stats_start_copy); 106 107 static void 108 __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats, 109 struct gnet_stats_basic_cpu __percpu *cpu) 110 { 111 int i; 112 113 for_each_possible_cpu(i) { 114 struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i); 115 unsigned int start; 116 u64 bytes; 117 u32 packets; 118 119 do { 120 start = u64_stats_fetch_begin_irq(&bcpu->syncp); 121 bytes = bcpu->bstats.bytes; 122 packets = bcpu->bstats.packets; 123 } while (u64_stats_fetch_retry_irq(&bcpu->syncp, start)); 124 125 bstats->bytes += bytes; 126 bstats->packets += packets; 127 } 128 } 129 130 void 131 __gnet_stats_copy_basic(const seqcount_t *running, 132 struct gnet_stats_basic_packed *bstats, 133 struct gnet_stats_basic_cpu __percpu *cpu, 134 struct gnet_stats_basic_packed *b) 135 { 136 unsigned int seq; 137 138 if (cpu) { 139 __gnet_stats_copy_basic_cpu(bstats, cpu); 140 return; 141 } 142 do { 143 if (running) 144 seq = read_seqcount_begin(running); 145 bstats->bytes = b->bytes; 146 bstats->packets = b->packets; 147 } while (running && read_seqcount_retry(running, seq)); 148 } 149 EXPORT_SYMBOL(__gnet_stats_copy_basic); 150 151 /** 152 * gnet_stats_copy_basic - copy basic statistics into statistic TLV 153 * @running: seqcount_t pointer 154 * @d: dumping handle 155 * @cpu: copy statistic per cpu 156 * @b: basic statistics 157 * 158 * Appends the basic statistics to the top level TLV created by 159 * gnet_stats_start_copy(). 160 * 161 * Returns 0 on success or -1 with the statistic lock released 162 * if the room in the socket buffer was not sufficient. 163 */ 164 int 165 gnet_stats_copy_basic(const seqcount_t *running, 166 struct gnet_dump *d, 167 struct gnet_stats_basic_cpu __percpu *cpu, 168 struct gnet_stats_basic_packed *b) 169 { 170 struct gnet_stats_basic_packed bstats = {0}; 171 172 __gnet_stats_copy_basic(running, &bstats, cpu, b); 173 174 if (d->compat_tc_stats) { 175 d->tc_stats.bytes = bstats.bytes; 176 d->tc_stats.packets = bstats.packets; 177 } 178 179 if (d->tail) { 180 struct gnet_stats_basic sb; 181 182 memset(&sb, 0, sizeof(sb)); 183 sb.bytes = bstats.bytes; 184 sb.packets = bstats.packets; 185 return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb), 186 TCA_STATS_PAD); 187 } 188 return 0; 189 } 190 EXPORT_SYMBOL(gnet_stats_copy_basic); 191 192 /** 193 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV 194 * @d: dumping handle 195 * @b: basic statistics 196 * @r: rate estimator statistics 197 * 198 * Appends the rate estimator statistics to the top level TLV created by 199 * gnet_stats_start_copy(). 200 * 201 * Returns 0 on success or -1 with the statistic lock released 202 * if the room in the socket buffer was not sufficient. 203 */ 204 int 205 gnet_stats_copy_rate_est(struct gnet_dump *d, 206 const struct gnet_stats_basic_packed *b, 207 struct gnet_stats_rate_est64 *r) 208 { 209 struct gnet_stats_rate_est est; 210 int res; 211 212 if (b && !gen_estimator_active(b, r)) 213 return 0; 214 215 est.bps = min_t(u64, UINT_MAX, r->bps); 216 /* we have some time before reaching 2^32 packets per second */ 217 est.pps = r->pps; 218 219 if (d->compat_tc_stats) { 220 d->tc_stats.bps = est.bps; 221 d->tc_stats.pps = est.pps; 222 } 223 224 if (d->tail) { 225 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est), 226 TCA_STATS_PAD); 227 if (res < 0 || est.bps == r->bps) 228 return res; 229 /* emit 64bit stats only if needed */ 230 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, r, sizeof(*r), 231 TCA_STATS_PAD); 232 } 233 234 return 0; 235 } 236 EXPORT_SYMBOL(gnet_stats_copy_rate_est); 237 238 static void 239 __gnet_stats_copy_queue_cpu(struct gnet_stats_queue *qstats, 240 const struct gnet_stats_queue __percpu *q) 241 { 242 int i; 243 244 for_each_possible_cpu(i) { 245 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 246 247 qstats->qlen = 0; 248 qstats->backlog += qcpu->backlog; 249 qstats->drops += qcpu->drops; 250 qstats->requeues += qcpu->requeues; 251 qstats->overlimits += qcpu->overlimits; 252 } 253 } 254 255 static void __gnet_stats_copy_queue(struct gnet_stats_queue *qstats, 256 const struct gnet_stats_queue __percpu *cpu, 257 const struct gnet_stats_queue *q, 258 __u32 qlen) 259 { 260 if (cpu) { 261 __gnet_stats_copy_queue_cpu(qstats, cpu); 262 } else { 263 qstats->qlen = q->qlen; 264 qstats->backlog = q->backlog; 265 qstats->drops = q->drops; 266 qstats->requeues = q->requeues; 267 qstats->overlimits = q->overlimits; 268 } 269 270 qstats->qlen = qlen; 271 } 272 273 /** 274 * gnet_stats_copy_queue - copy queue statistics into statistics TLV 275 * @d: dumping handle 276 * @cpu_q: per cpu queue statistics 277 * @q: queue statistics 278 * @qlen: queue length statistics 279 * 280 * Appends the queue statistics to the top level TLV created by 281 * gnet_stats_start_copy(). Using per cpu queue statistics if 282 * they are available. 283 * 284 * Returns 0 on success or -1 with the statistic lock released 285 * if the room in the socket buffer was not sufficient. 286 */ 287 int 288 gnet_stats_copy_queue(struct gnet_dump *d, 289 struct gnet_stats_queue __percpu *cpu_q, 290 struct gnet_stats_queue *q, __u32 qlen) 291 { 292 struct gnet_stats_queue qstats = {0}; 293 294 __gnet_stats_copy_queue(&qstats, cpu_q, q, qlen); 295 296 if (d->compat_tc_stats) { 297 d->tc_stats.drops = qstats.drops; 298 d->tc_stats.qlen = qstats.qlen; 299 d->tc_stats.backlog = qstats.backlog; 300 d->tc_stats.overlimits = qstats.overlimits; 301 } 302 303 if (d->tail) 304 return gnet_stats_copy(d, TCA_STATS_QUEUE, 305 &qstats, sizeof(qstats), 306 TCA_STATS_PAD); 307 308 return 0; 309 } 310 EXPORT_SYMBOL(gnet_stats_copy_queue); 311 312 /** 313 * gnet_stats_copy_app - copy application specific statistics into statistics TLV 314 * @d: dumping handle 315 * @st: application specific statistics data 316 * @len: length of data 317 * 318 * Appends the application specific statistics to the top level TLV created by 319 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping 320 * handle is in backward compatibility mode. 321 * 322 * Returns 0 on success or -1 with the statistic lock released 323 * if the room in the socket buffer was not sufficient. 324 */ 325 int 326 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) 327 { 328 if (d->compat_xstats) { 329 d->xstats = kmemdup(st, len, GFP_ATOMIC); 330 if (!d->xstats) 331 goto err_out; 332 d->xstats_len = len; 333 } 334 335 if (d->tail) 336 return gnet_stats_copy(d, TCA_STATS_APP, st, len, 337 TCA_STATS_PAD); 338 339 return 0; 340 341 err_out: 342 if (d->lock) 343 spin_unlock_bh(d->lock); 344 d->xstats_len = 0; 345 return -1; 346 } 347 EXPORT_SYMBOL(gnet_stats_copy_app); 348 349 /** 350 * gnet_stats_finish_copy - finish dumping procedure 351 * @d: dumping handle 352 * 353 * Corrects the length of the top level TLV to include all TLVs added 354 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs 355 * if gnet_stats_start_copy_compat() was used and releases the statistics 356 * lock. 357 * 358 * Returns 0 on success or -1 with the statistic lock released 359 * if the room in the socket buffer was not sufficient. 360 */ 361 int 362 gnet_stats_finish_copy(struct gnet_dump *d) 363 { 364 if (d->tail) 365 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail; 366 367 if (d->compat_tc_stats) 368 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats, 369 sizeof(d->tc_stats), d->padattr) < 0) 370 return -1; 371 372 if (d->compat_xstats && d->xstats) { 373 if (gnet_stats_copy(d, d->compat_xstats, d->xstats, 374 d->xstats_len, d->padattr) < 0) 375 return -1; 376 } 377 378 if (d->lock) 379 spin_unlock_bh(d->lock); 380 kfree(d->xstats); 381 d->xstats = NULL; 382 d->xstats_len = 0; 383 return 0; 384 } 385 EXPORT_SYMBOL(gnet_stats_finish_copy); 386