| 1 | /* |
| 2 | * taskstats.c - Export per-task statistics to userland |
| 3 | * |
| 4 | * Copyright (C) Shailabh Nagar, IBM Corp. 2006 |
| 5 | * (C) Balbir Singh, IBM Corp. 2006 |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/taskstats_kern.h> |
| 21 | #include <linux/tsacct_kern.h> |
| 22 | #include <linux/delayacct.h> |
| 23 | #include <linux/cpumask.h> |
| 24 | #include <linux/percpu.h> |
| 25 | #include <linux/slab.h> |
| 26 | #include <linux/cgroupstats.h> |
| 27 | #include <linux/cgroup.h> |
| 28 | #include <linux/fs.h> |
| 29 | #include <linux/file.h> |
| 30 | #include <net/genetlink.h> |
| 31 | #include <asm/atomic.h> |
| 32 | |
| 33 | /* |
| 34 | * Maximum length of a cpumask that can be specified in |
| 35 | * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute |
| 36 | */ |
| 37 | #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS) |
| 38 | |
| 39 | static DEFINE_PER_CPU(__u32, taskstats_seqnum); |
| 40 | static int family_registered; |
| 41 | struct kmem_cache *taskstats_cache; |
| 42 | |
| 43 | static struct genl_family family = { |
| 44 | .id = GENL_ID_GENERATE, |
| 45 | .name = TASKSTATS_GENL_NAME, |
| 46 | .version = TASKSTATS_GENL_VERSION, |
| 47 | .maxattr = TASKSTATS_CMD_ATTR_MAX, |
| 48 | }; |
| 49 | |
| 50 | static const struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = { |
| 51 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
| 52 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, |
| 53 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
| 54 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; |
| 55 | |
| 56 | static const struct nla_policy cgroupstats_cmd_get_policy[CGROUPSTATS_CMD_ATTR_MAX+1] = { |
| 57 | [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 }, |
| 58 | }; |
| 59 | |
| 60 | struct listener { |
| 61 | struct list_head list; |
| 62 | pid_t pid; |
| 63 | char valid; |
| 64 | }; |
| 65 | |
| 66 | struct listener_list { |
| 67 | struct rw_semaphore sem; |
| 68 | struct list_head list; |
| 69 | }; |
| 70 | static DEFINE_PER_CPU(struct listener_list, listener_array); |
| 71 | |
| 72 | enum actions { |
| 73 | REGISTER, |
| 74 | DEREGISTER, |
| 75 | CPU_DONT_CARE |
| 76 | }; |
| 77 | |
| 78 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, |
| 79 | size_t size) |
| 80 | { |
| 81 | struct sk_buff *skb; |
| 82 | void *reply; |
| 83 | |
| 84 | /* |
| 85 | * If new attributes are added, please revisit this allocation |
| 86 | */ |
| 87 | skb = genlmsg_new(size, GFP_KERNEL); |
| 88 | if (!skb) |
| 89 | return -ENOMEM; |
| 90 | |
| 91 | if (!info) { |
| 92 | int seq = get_cpu_var(taskstats_seqnum)++; |
| 93 | put_cpu_var(taskstats_seqnum); |
| 94 | |
| 95 | reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); |
| 96 | } else |
| 97 | reply = genlmsg_put_reply(skb, info, &family, 0, cmd); |
| 98 | if (reply == NULL) { |
| 99 | nlmsg_free(skb); |
| 100 | return -EINVAL; |
| 101 | } |
| 102 | |
| 103 | *skbp = skb; |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Send taskstats data in @skb to listener with nl_pid @pid |
| 109 | */ |
| 110 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
| 111 | { |
| 112 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
| 113 | void *reply = genlmsg_data(genlhdr); |
| 114 | int rc; |
| 115 | |
| 116 | rc = genlmsg_end(skb, reply); |
| 117 | if (rc < 0) { |
| 118 | nlmsg_free(skb); |
| 119 | return rc; |
| 120 | } |
| 121 | |
| 122 | return genlmsg_reply(skb, info); |
| 123 | } |
| 124 | |
| 125 | /* |
| 126 | * Send taskstats data in @skb to listeners registered for @cpu's exit data |
| 127 | */ |
| 128 | static void send_cpu_listeners(struct sk_buff *skb, |
| 129 | struct listener_list *listeners) |
| 130 | { |
| 131 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
| 132 | struct listener *s, *tmp; |
| 133 | struct sk_buff *skb_next, *skb_cur = skb; |
| 134 | void *reply = genlmsg_data(genlhdr); |
| 135 | int rc, delcount = 0; |
| 136 | |
| 137 | rc = genlmsg_end(skb, reply); |
| 138 | if (rc < 0) { |
| 139 | nlmsg_free(skb); |
| 140 | return; |
| 141 | } |
| 142 | |
| 143 | rc = 0; |
| 144 | down_read(&listeners->sem); |
| 145 | list_for_each_entry(s, &listeners->list, list) { |
| 146 | skb_next = NULL; |
| 147 | if (!list_is_last(&s->list, &listeners->list)) { |
| 148 | skb_next = skb_clone(skb_cur, GFP_KERNEL); |
| 149 | if (!skb_next) |
| 150 | break; |
| 151 | } |
| 152 | rc = genlmsg_unicast(&init_net, skb_cur, s->pid); |
| 153 | if (rc == -ECONNREFUSED) { |
| 154 | s->valid = 0; |
| 155 | delcount++; |
| 156 | } |
| 157 | skb_cur = skb_next; |
| 158 | } |
| 159 | up_read(&listeners->sem); |
| 160 | |
| 161 | if (skb_cur) |
| 162 | nlmsg_free(skb_cur); |
| 163 | |
| 164 | if (!delcount) |
| 165 | return; |
| 166 | |
| 167 | /* Delete invalidated entries */ |
| 168 | down_write(&listeners->sem); |
| 169 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
| 170 | if (!s->valid) { |
| 171 | list_del(&s->list); |
| 172 | kfree(s); |
| 173 | } |
| 174 | } |
| 175 | up_write(&listeners->sem); |
| 176 | } |
| 177 | |
| 178 | static int fill_pid(pid_t pid, struct task_struct *tsk, |
| 179 | struct taskstats *stats) |
| 180 | { |
| 181 | int rc = 0; |
| 182 | |
| 183 | if (!tsk) { |
| 184 | rcu_read_lock(); |
| 185 | tsk = find_task_by_vpid(pid); |
| 186 | if (tsk) |
| 187 | get_task_struct(tsk); |
| 188 | rcu_read_unlock(); |
| 189 | if (!tsk) |
| 190 | return -ESRCH; |
| 191 | } else |
| 192 | get_task_struct(tsk); |
| 193 | |
| 194 | memset(stats, 0, sizeof(*stats)); |
| 195 | /* |
| 196 | * Each accounting subsystem adds calls to its functions to |
| 197 | * fill in relevant parts of struct taskstsats as follows |
| 198 | * |
| 199 | * per-task-foo(stats, tsk); |
| 200 | */ |
| 201 | |
| 202 | delayacct_add_tsk(stats, tsk); |
| 203 | |
| 204 | /* fill in basic acct fields */ |
| 205 | stats->version = TASKSTATS_VERSION; |
| 206 | stats->nvcsw = tsk->nvcsw; |
| 207 | stats->nivcsw = tsk->nivcsw; |
| 208 | bacct_add_tsk(stats, tsk); |
| 209 | |
| 210 | /* fill in extended acct fields */ |
| 211 | xacct_add_tsk(stats, tsk); |
| 212 | |
| 213 | /* Define err: label here if needed */ |
| 214 | put_task_struct(tsk); |
| 215 | return rc; |
| 216 | |
| 217 | } |
| 218 | |
| 219 | static int fill_tgid(pid_t tgid, struct task_struct *first, |
| 220 | struct taskstats *stats) |
| 221 | { |
| 222 | struct task_struct *tsk; |
| 223 | unsigned long flags; |
| 224 | int rc = -ESRCH; |
| 225 | |
| 226 | /* |
| 227 | * Add additional stats from live tasks except zombie thread group |
| 228 | * leaders who are already counted with the dead tasks |
| 229 | */ |
| 230 | rcu_read_lock(); |
| 231 | if (!first) |
| 232 | first = find_task_by_vpid(tgid); |
| 233 | |
| 234 | if (!first || !lock_task_sighand(first, &flags)) |
| 235 | goto out; |
| 236 | |
| 237 | if (first->signal->stats) |
| 238 | memcpy(stats, first->signal->stats, sizeof(*stats)); |
| 239 | else |
| 240 | memset(stats, 0, sizeof(*stats)); |
| 241 | |
| 242 | tsk = first; |
| 243 | do { |
| 244 | if (tsk->exit_state) |
| 245 | continue; |
| 246 | /* |
| 247 | * Accounting subsystem can call its functions here to |
| 248 | * fill in relevant parts of struct taskstsats as follows |
| 249 | * |
| 250 | * per-task-foo(stats, tsk); |
| 251 | */ |
| 252 | delayacct_add_tsk(stats, tsk); |
| 253 | |
| 254 | stats->nvcsw += tsk->nvcsw; |
| 255 | stats->nivcsw += tsk->nivcsw; |
| 256 | } while_each_thread(first, tsk); |
| 257 | |
| 258 | unlock_task_sighand(first, &flags); |
| 259 | rc = 0; |
| 260 | out: |
| 261 | rcu_read_unlock(); |
| 262 | |
| 263 | stats->version = TASKSTATS_VERSION; |
| 264 | /* |
| 265 | * Accounting subsystems can also add calls here to modify |
| 266 | * fields of taskstats. |
| 267 | */ |
| 268 | return rc; |
| 269 | } |
| 270 | |
| 271 | |
| 272 | static void fill_tgid_exit(struct task_struct *tsk) |
| 273 | { |
| 274 | unsigned long flags; |
| 275 | |
| 276 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
| 277 | if (!tsk->signal->stats) |
| 278 | goto ret; |
| 279 | |
| 280 | /* |
| 281 | * Each accounting subsystem calls its functions here to |
| 282 | * accumalate its per-task stats for tsk, into the per-tgid structure |
| 283 | * |
| 284 | * per-task-foo(tsk->signal->stats, tsk); |
| 285 | */ |
| 286 | delayacct_add_tsk(tsk->signal->stats, tsk); |
| 287 | ret: |
| 288 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
| 289 | return; |
| 290 | } |
| 291 | |
| 292 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
| 293 | { |
| 294 | struct listener_list *listeners; |
| 295 | struct listener *s, *tmp; |
| 296 | unsigned int cpu; |
| 297 | |
| 298 | if (!cpumask_subset(mask, cpu_possible_mask)) |
| 299 | return -EINVAL; |
| 300 | |
| 301 | if (isadd == REGISTER) { |
| 302 | for_each_cpu(cpu, mask) { |
| 303 | s = kmalloc_node(sizeof(struct listener), GFP_KERNEL, |
| 304 | cpu_to_node(cpu)); |
| 305 | if (!s) |
| 306 | goto cleanup; |
| 307 | s->pid = pid; |
| 308 | INIT_LIST_HEAD(&s->list); |
| 309 | s->valid = 1; |
| 310 | |
| 311 | listeners = &per_cpu(listener_array, cpu); |
| 312 | down_write(&listeners->sem); |
| 313 | list_add(&s->list, &listeners->list); |
| 314 | up_write(&listeners->sem); |
| 315 | } |
| 316 | return 0; |
| 317 | } |
| 318 | |
| 319 | /* Deregister or cleanup */ |
| 320 | cleanup: |
| 321 | for_each_cpu(cpu, mask) { |
| 322 | listeners = &per_cpu(listener_array, cpu); |
| 323 | down_write(&listeners->sem); |
| 324 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
| 325 | if (s->pid == pid) { |
| 326 | list_del(&s->list); |
| 327 | kfree(s); |
| 328 | break; |
| 329 | } |
| 330 | } |
| 331 | up_write(&listeners->sem); |
| 332 | } |
| 333 | return 0; |
| 334 | } |
| 335 | |
| 336 | static int parse(struct nlattr *na, struct cpumask *mask) |
| 337 | { |
| 338 | char *data; |
| 339 | int len; |
| 340 | int ret; |
| 341 | |
| 342 | if (na == NULL) |
| 343 | return 1; |
| 344 | len = nla_len(na); |
| 345 | if (len > TASKSTATS_CPUMASK_MAXLEN) |
| 346 | return -E2BIG; |
| 347 | if (len < 1) |
| 348 | return -EINVAL; |
| 349 | data = kmalloc(len, GFP_KERNEL); |
| 350 | if (!data) |
| 351 | return -ENOMEM; |
| 352 | nla_strlcpy(data, na, len); |
| 353 | ret = cpulist_parse(data, mask); |
| 354 | kfree(data); |
| 355 | return ret; |
| 356 | } |
| 357 | |
| 358 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
| 359 | { |
| 360 | struct nlattr *na, *ret; |
| 361 | int aggr; |
| 362 | |
| 363 | aggr = (type == TASKSTATS_TYPE_PID) |
| 364 | ? TASKSTATS_TYPE_AGGR_PID |
| 365 | : TASKSTATS_TYPE_AGGR_TGID; |
| 366 | |
| 367 | na = nla_nest_start(skb, aggr); |
| 368 | if (!na) |
| 369 | goto err; |
| 370 | if (nla_put(skb, type, sizeof(pid), &pid) < 0) |
| 371 | goto err; |
| 372 | ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); |
| 373 | if (!ret) |
| 374 | goto err; |
| 375 | nla_nest_end(skb, na); |
| 376 | |
| 377 | return nla_data(ret); |
| 378 | err: |
| 379 | return NULL; |
| 380 | } |
| 381 | |
| 382 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
| 383 | { |
| 384 | int rc = 0; |
| 385 | struct sk_buff *rep_skb; |
| 386 | struct cgroupstats *stats; |
| 387 | struct nlattr *na; |
| 388 | size_t size; |
| 389 | u32 fd; |
| 390 | struct file *file; |
| 391 | int fput_needed; |
| 392 | |
| 393 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; |
| 394 | if (!na) |
| 395 | return -EINVAL; |
| 396 | |
| 397 | fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]); |
| 398 | file = fget_light(fd, &fput_needed); |
| 399 | if (!file) |
| 400 | return 0; |
| 401 | |
| 402 | size = nla_total_size(sizeof(struct cgroupstats)); |
| 403 | |
| 404 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
| 405 | size); |
| 406 | if (rc < 0) |
| 407 | goto err; |
| 408 | |
| 409 | na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS, |
| 410 | sizeof(struct cgroupstats)); |
| 411 | stats = nla_data(na); |
| 412 | memset(stats, 0, sizeof(*stats)); |
| 413 | |
| 414 | rc = cgroupstats_build(stats, file->f_dentry); |
| 415 | if (rc < 0) { |
| 416 | nlmsg_free(rep_skb); |
| 417 | goto err; |
| 418 | } |
| 419 | |
| 420 | rc = send_reply(rep_skb, info); |
| 421 | |
| 422 | err: |
| 423 | fput_light(file, fput_needed); |
| 424 | return rc; |
| 425 | } |
| 426 | |
| 427 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
| 428 | { |
| 429 | int rc; |
| 430 | struct sk_buff *rep_skb; |
| 431 | struct taskstats *stats; |
| 432 | size_t size; |
| 433 | cpumask_var_t mask; |
| 434 | |
| 435 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
| 436 | return -ENOMEM; |
| 437 | |
| 438 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
| 439 | if (rc < 0) |
| 440 | goto free_return_rc; |
| 441 | if (rc == 0) { |
| 442 | rc = add_del_listener(info->snd_pid, mask, REGISTER); |
| 443 | goto free_return_rc; |
| 444 | } |
| 445 | |
| 446 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
| 447 | if (rc < 0) |
| 448 | goto free_return_rc; |
| 449 | if (rc == 0) { |
| 450 | rc = add_del_listener(info->snd_pid, mask, DEREGISTER); |
| 451 | free_return_rc: |
| 452 | free_cpumask_var(mask); |
| 453 | return rc; |
| 454 | } |
| 455 | free_cpumask_var(mask); |
| 456 | |
| 457 | /* |
| 458 | * Size includes space for nested attributes |
| 459 | */ |
| 460 | size = nla_total_size(sizeof(u32)) + |
| 461 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); |
| 462 | |
| 463 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
| 464 | if (rc < 0) |
| 465 | return rc; |
| 466 | |
| 467 | rc = -EINVAL; |
| 468 | if (info->attrs[TASKSTATS_CMD_ATTR_PID]) { |
| 469 | u32 pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
| 470 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); |
| 471 | if (!stats) |
| 472 | goto err; |
| 473 | |
| 474 | rc = fill_pid(pid, NULL, stats); |
| 475 | if (rc < 0) |
| 476 | goto err; |
| 477 | } else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) { |
| 478 | u32 tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); |
| 479 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); |
| 480 | if (!stats) |
| 481 | goto err; |
| 482 | |
| 483 | rc = fill_tgid(tgid, NULL, stats); |
| 484 | if (rc < 0) |
| 485 | goto err; |
| 486 | } else |
| 487 | goto err; |
| 488 | |
| 489 | return send_reply(rep_skb, info); |
| 490 | err: |
| 491 | nlmsg_free(rep_skb); |
| 492 | return rc; |
| 493 | } |
| 494 | |
| 495 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
| 496 | { |
| 497 | struct signal_struct *sig = tsk->signal; |
| 498 | struct taskstats *stats; |
| 499 | |
| 500 | if (sig->stats || thread_group_empty(tsk)) |
| 501 | goto ret; |
| 502 | |
| 503 | /* No problem if kmem_cache_zalloc() fails */ |
| 504 | stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); |
| 505 | |
| 506 | spin_lock_irq(&tsk->sighand->siglock); |
| 507 | if (!sig->stats) { |
| 508 | sig->stats = stats; |
| 509 | stats = NULL; |
| 510 | } |
| 511 | spin_unlock_irq(&tsk->sighand->siglock); |
| 512 | |
| 513 | if (stats) |
| 514 | kmem_cache_free(taskstats_cache, stats); |
| 515 | ret: |
| 516 | return sig->stats; |
| 517 | } |
| 518 | |
| 519 | /* Send pid data out on exit */ |
| 520 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
| 521 | { |
| 522 | int rc; |
| 523 | struct listener_list *listeners; |
| 524 | struct taskstats *stats; |
| 525 | struct sk_buff *rep_skb; |
| 526 | size_t size; |
| 527 | int is_thread_group; |
| 528 | |
| 529 | if (!family_registered) |
| 530 | return; |
| 531 | |
| 532 | /* |
| 533 | * Size includes space for nested attributes |
| 534 | */ |
| 535 | size = nla_total_size(sizeof(u32)) + |
| 536 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); |
| 537 | |
| 538 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
| 539 | if (is_thread_group) { |
| 540 | /* PID + STATS + TGID + STATS */ |
| 541 | size = 2 * size; |
| 542 | /* fill the tsk->signal->stats structure */ |
| 543 | fill_tgid_exit(tsk); |
| 544 | } |
| 545 | |
| 546 | listeners = &__raw_get_cpu_var(listener_array); |
| 547 | if (list_empty(&listeners->list)) |
| 548 | return; |
| 549 | |
| 550 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
| 551 | if (rc < 0) |
| 552 | return; |
| 553 | |
| 554 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid); |
| 555 | if (!stats) |
| 556 | goto err; |
| 557 | |
| 558 | rc = fill_pid(-1, tsk, stats); |
| 559 | if (rc < 0) |
| 560 | goto err; |
| 561 | |
| 562 | /* |
| 563 | * Doesn't matter if tsk is the leader or the last group member leaving |
| 564 | */ |
| 565 | if (!is_thread_group || !group_dead) |
| 566 | goto send; |
| 567 | |
| 568 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid); |
| 569 | if (!stats) |
| 570 | goto err; |
| 571 | |
| 572 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); |
| 573 | |
| 574 | send: |
| 575 | send_cpu_listeners(rep_skb, listeners); |
| 576 | return; |
| 577 | err: |
| 578 | nlmsg_free(rep_skb); |
| 579 | } |
| 580 | |
| 581 | static struct genl_ops taskstats_ops = { |
| 582 | .cmd = TASKSTATS_CMD_GET, |
| 583 | .doit = taskstats_user_cmd, |
| 584 | .policy = taskstats_cmd_get_policy, |
| 585 | }; |
| 586 | |
| 587 | static struct genl_ops cgroupstats_ops = { |
| 588 | .cmd = CGROUPSTATS_CMD_GET, |
| 589 | .doit = cgroupstats_user_cmd, |
| 590 | .policy = cgroupstats_cmd_get_policy, |
| 591 | }; |
| 592 | |
| 593 | /* Needed early in initialization */ |
| 594 | void __init taskstats_init_early(void) |
| 595 | { |
| 596 | unsigned int i; |
| 597 | |
| 598 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
| 599 | for_each_possible_cpu(i) { |
| 600 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); |
| 601 | init_rwsem(&(per_cpu(listener_array, i).sem)); |
| 602 | } |
| 603 | } |
| 604 | |
| 605 | static int __init taskstats_init(void) |
| 606 | { |
| 607 | int rc; |
| 608 | |
| 609 | rc = genl_register_family(&family); |
| 610 | if (rc) |
| 611 | return rc; |
| 612 | |
| 613 | rc = genl_register_ops(&family, &taskstats_ops); |
| 614 | if (rc < 0) |
| 615 | goto err; |
| 616 | |
| 617 | rc = genl_register_ops(&family, &cgroupstats_ops); |
| 618 | if (rc < 0) |
| 619 | goto err_cgroup_ops; |
| 620 | |
| 621 | family_registered = 1; |
| 622 | printk("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
| 623 | return 0; |
| 624 | err_cgroup_ops: |
| 625 | genl_unregister_ops(&family, &taskstats_ops); |
| 626 | err: |
| 627 | genl_unregister_family(&family); |
| 628 | return rc; |
| 629 | } |
| 630 | |
| 631 | /* |
| 632 | * late initcall ensures initialization of statistics collection |
| 633 | * mechanisms precedes initialization of the taskstats interface |
| 634 | */ |
| 635 | late_initcall(taskstats_init); |