Line data Source code
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 <linux/pid_namespace.h>
31 : #include <net/genetlink.h>
32 : #include <linux/atomic.h>
33 :
34 : /*
35 : * Maximum length of a cpumask that can be specified in
36 : * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute
37 : */
38 : #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS)
39 :
40 : static DEFINE_PER_CPU(__u32, taskstats_seqnum);
41 : static int family_registered;
42 : struct kmem_cache *taskstats_cache;
43 :
44 : static struct genl_family family = {
45 : .id = GENL_ID_GENERATE,
46 : .name = TASKSTATS_GENL_NAME,
47 : .version = TASKSTATS_GENL_VERSION,
48 : .maxattr = TASKSTATS_CMD_ATTR_MAX,
49 : };
50 :
51 : static const struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = {
52 : [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 },
53 : [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 },
54 : [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING },
55 : [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },};
56 :
57 : static const struct nla_policy cgroupstats_cmd_get_policy[CGROUPSTATS_CMD_ATTR_MAX+1] = {
58 : [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 },
59 : };
60 :
61 : struct listener {
62 : struct list_head list;
63 : pid_t pid;
64 : char valid;
65 : };
66 :
67 : struct listener_list {
68 : struct rw_semaphore sem;
69 : struct list_head list;
70 : };
71 : static DEFINE_PER_CPU(struct listener_list, listener_array);
72 :
73 : enum actions {
74 : REGISTER,
75 : DEREGISTER,
76 : CPU_DONT_CARE
77 : };
78 :
79 0 : static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
80 : size_t size)
81 : {
82 : struct sk_buff *skb;
83 : void *reply;
84 :
85 : /*
86 : * If new attributes are added, please revisit this allocation
87 : */
88 : skb = genlmsg_new(size, GFP_KERNEL);
89 0 : if (!skb)
90 : return -ENOMEM;
91 :
92 0 : if (!info) {
93 0 : int seq = this_cpu_inc_return(taskstats_seqnum) - 1;
94 :
95 0 : reply = genlmsg_put(skb, 0, seq, &family, 0, cmd);
96 : } else
97 : reply = genlmsg_put_reply(skb, info, &family, 0, cmd);
98 0 : if (reply == NULL) {
99 : nlmsg_free(skb);
100 0 : return -EINVAL;
101 : }
102 :
103 0 : *skbp = skb;
104 0 : return 0;
105 : }
106 :
107 : /*
108 : * Send taskstats data in @skb to listener with nl_pid @pid
109 : */
110 0 : 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 0 : if (rc < 0) {
118 : nlmsg_free(skb);
119 0 : return rc;
120 : }
121 :
122 0 : return genlmsg_reply(skb, info);
123 : }
124 :
125 : /*
126 : * Send taskstats data in @skb to listeners registered for @cpu's exit data
127 : */
128 0 : 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 0 : if (rc < 0) {
139 : nlmsg_free(skb);
140 : return;
141 : }
142 :
143 : rc = 0;
144 0 : down_read(&listeners->sem);
145 0 : list_for_each_entry(s, &listeners->list, list) {
146 : skb_next = NULL;
147 0 : if (!list_is_last(&s->list, &listeners->list)) {
148 0 : skb_next = skb_clone(skb_cur, GFP_KERNEL);
149 0 : if (!skb_next)
150 : break;
151 : }
152 0 : rc = genlmsg_unicast(&init_net, skb_cur, s->pid);
153 0 : if (rc == -ECONNREFUSED) {
154 0 : s->valid = 0;
155 0 : delcount++;
156 : }
157 : skb_cur = skb_next;
158 : }
159 0 : up_read(&listeners->sem);
160 :
161 0 : if (skb_cur)
162 : nlmsg_free(skb_cur);
163 :
164 0 : if (!delcount)
165 : return;
166 :
167 : /* Delete invalidated entries */
168 0 : down_write(&listeners->sem);
169 0 : list_for_each_entry_safe(s, tmp, &listeners->list, list) {
170 0 : if (!s->valid) {
171 : list_del(&s->list);
172 0 : kfree(s);
173 : }
174 : }
175 0 : up_write(&listeners->sem);
176 : }
177 :
178 0 : static void fill_stats(struct user_namespace *user_ns,
179 : struct pid_namespace *pid_ns,
180 : struct task_struct *tsk, struct taskstats *stats)
181 : {
182 0 : memset(stats, 0, sizeof(*stats));
183 : /*
184 : * Each accounting subsystem adds calls to its functions to
185 : * fill in relevant parts of struct taskstsats as follows
186 : *
187 : * per-task-foo(stats, tsk);
188 : */
189 :
190 : delayacct_add_tsk(stats, tsk);
191 :
192 : /* fill in basic acct fields */
193 0 : stats->version = TASKSTATS_VERSION;
194 0 : stats->nvcsw = tsk->nvcsw;
195 0 : stats->nivcsw = tsk->nivcsw;
196 0 : bacct_add_tsk(user_ns, pid_ns, stats, tsk);
197 :
198 : /* fill in extended acct fields */
199 0 : xacct_add_tsk(stats, tsk);
200 0 : }
201 :
202 0 : static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
203 : {
204 : struct task_struct *tsk;
205 :
206 : rcu_read_lock();
207 0 : tsk = find_task_by_vpid(pid);
208 0 : if (tsk)
209 0 : get_task_struct(tsk);
210 : rcu_read_unlock();
211 0 : if (!tsk)
212 : return -ESRCH;
213 0 : fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats);
214 : put_task_struct(tsk);
215 : return 0;
216 : }
217 :
218 0 : static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
219 : {
220 : struct task_struct *tsk, *first;
221 : unsigned long flags;
222 : int rc = -ESRCH;
223 :
224 : /*
225 : * Add additional stats from live tasks except zombie thread group
226 : * leaders who are already counted with the dead tasks
227 : */
228 : rcu_read_lock();
229 0 : first = find_task_by_vpid(tgid);
230 :
231 0 : if (!first || !lock_task_sighand(first, &flags))
232 : goto out;
233 :
234 0 : if (first->signal->stats)
235 0 : memcpy(stats, first->signal->stats, sizeof(*stats));
236 : else
237 0 : memset(stats, 0, sizeof(*stats));
238 :
239 : tsk = first;
240 : do {
241 0 : if (tsk->exit_state)
242 0 : continue;
243 : /*
244 : * Accounting subsystem can call its functions here to
245 : * fill in relevant parts of struct taskstsats as follows
246 : *
247 : * per-task-foo(stats, tsk);
248 : */
249 : delayacct_add_tsk(stats, tsk);
250 :
251 0 : stats->nvcsw += tsk->nvcsw;
252 0 : stats->nivcsw += tsk->nivcsw;
253 0 : } while_each_thread(first, tsk);
254 :
255 0 : unlock_task_sighand(first, &flags);
256 : rc = 0;
257 : out:
258 : rcu_read_unlock();
259 :
260 0 : stats->version = TASKSTATS_VERSION;
261 : /*
262 : * Accounting subsystems can also add calls here to modify
263 : * fields of taskstats.
264 : */
265 0 : return rc;
266 : }
267 :
268 0 : static void fill_tgid_exit(struct task_struct *tsk)
269 : {
270 : unsigned long flags;
271 :
272 0 : spin_lock_irqsave(&tsk->sighand->siglock, flags);
273 0 : if (!tsk->signal->stats)
274 : goto ret;
275 :
276 : /*
277 : * Each accounting subsystem calls its functions here to
278 : * accumalate its per-task stats for tsk, into the per-tgid structure
279 : *
280 : * per-task-foo(tsk->signal->stats, tsk);
281 : */
282 : delayacct_add_tsk(tsk->signal->stats, tsk);
283 : ret:
284 : spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
285 0 : return;
286 : }
287 :
288 0 : static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd)
289 : {
290 : struct listener_list *listeners;
291 : struct listener *s, *tmp, *s2;
292 : unsigned int cpu;
293 : int ret = 0;
294 :
295 0 : if (!cpumask_subset(mask, cpu_possible_mask))
296 : return -EINVAL;
297 :
298 : if (current_user_ns() != &init_user_ns)
299 : return -EINVAL;
300 :
301 0 : if (task_active_pid_ns(current) != &init_pid_ns)
302 : return -EINVAL;
303 :
304 0 : if (isadd == REGISTER) {
305 0 : for_each_cpu(cpu, mask) {
306 : s = kmalloc_node(sizeof(struct listener),
307 : GFP_KERNEL, cpu_to_node(cpu));
308 0 : if (!s) {
309 : ret = -ENOMEM;
310 : goto cleanup;
311 : }
312 0 : s->pid = pid;
313 0 : s->valid = 1;
314 :
315 : listeners = &per_cpu(listener_array, cpu);
316 0 : down_write(&listeners->sem);
317 0 : list_for_each_entry(s2, &listeners->list, list) {
318 0 : if (s2->pid == pid && s2->valid)
319 : goto exists;
320 : }
321 0 : list_add(&s->list, &listeners->list);
322 : s = NULL;
323 : exists:
324 0 : up_write(&listeners->sem);
325 0 : kfree(s); /* nop if NULL */
326 : }
327 : return 0;
328 : }
329 :
330 : /* Deregister or cleanup */
331 : cleanup:
332 0 : for_each_cpu(cpu, mask) {
333 : listeners = &per_cpu(listener_array, cpu);
334 0 : down_write(&listeners->sem);
335 0 : list_for_each_entry_safe(s, tmp, &listeners->list, list) {
336 0 : if (s->pid == pid) {
337 : list_del(&s->list);
338 0 : kfree(s);
339 0 : break;
340 : }
341 : }
342 0 : up_write(&listeners->sem);
343 : }
344 : return ret;
345 : }
346 :
347 0 : static int parse(struct nlattr *na, struct cpumask *mask)
348 : {
349 : char *data;
350 : int len;
351 : int ret;
352 :
353 0 : if (na == NULL)
354 : return 1;
355 : len = nla_len(na);
356 0 : if (len > TASKSTATS_CPUMASK_MAXLEN)
357 : return -E2BIG;
358 0 : if (len < 1)
359 : return -EINVAL;
360 0 : data = kmalloc(len, GFP_KERNEL);
361 0 : if (!data)
362 : return -ENOMEM;
363 0 : nla_strlcpy(data, na, len);
364 : ret = cpulist_parse(data, mask);
365 0 : kfree(data);
366 0 : return ret;
367 : }
368 :
369 : #if defined(CONFIG_64BIT) && !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
370 : #define TASKSTATS_NEEDS_PADDING 1
371 : #endif
372 :
373 0 : static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
374 : {
375 : struct nlattr *na, *ret;
376 : int aggr;
377 :
378 : aggr = (type == TASKSTATS_TYPE_PID)
379 : ? TASKSTATS_TYPE_AGGR_PID
380 0 : : TASKSTATS_TYPE_AGGR_TGID;
381 :
382 : /*
383 : * The taskstats structure is internally aligned on 8 byte
384 : * boundaries but the layout of the aggregrate reply, with
385 : * two NLA headers and the pid (each 4 bytes), actually
386 : * force the entire structure to be unaligned. This causes
387 : * the kernel to issue unaligned access warnings on some
388 : * architectures like ia64. Unfortunately, some software out there
389 : * doesn't properly unroll the NLA packet and assumes that the start
390 : * of the taskstats structure will always be 20 bytes from the start
391 : * of the netlink payload. Aligning the start of the taskstats
392 : * structure breaks this software, which we don't want. So, for now
393 : * the alignment only happens on architectures that require it
394 : * and those users will have to update to fixed versions of those
395 : * packages. Space is reserved in the packet only when needed.
396 : * This ifdef should be removed in several years e.g. 2012 once
397 : * we can be confident that fixed versions are installed on most
398 : * systems. We add the padding before the aggregate since the
399 : * aggregate is already a defined type.
400 : */
401 : #ifdef TASKSTATS_NEEDS_PADDING
402 : if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0)
403 : goto err;
404 : #endif
405 : na = nla_nest_start(skb, aggr);
406 0 : if (!na)
407 : goto err;
408 :
409 0 : if (nla_put(skb, type, sizeof(pid), &pid) < 0) {
410 : nla_nest_cancel(skb, na);
411 : goto err;
412 : }
413 0 : ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
414 0 : if (!ret) {
415 : nla_nest_cancel(skb, na);
416 : goto err;
417 : }
418 : nla_nest_end(skb, na);
419 :
420 0 : return nla_data(ret);
421 : err:
422 : return NULL;
423 : }
424 :
425 0 : static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
426 : {
427 : int rc = 0;
428 : struct sk_buff *rep_skb;
429 : struct cgroupstats *stats;
430 : struct nlattr *na;
431 : size_t size;
432 : u32 fd;
433 : struct fd f;
434 :
435 0 : na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
436 0 : if (!na)
437 : return -EINVAL;
438 :
439 : fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
440 : f = fdget(fd);
441 0 : if (!f.file)
442 : return 0;
443 :
444 : size = nla_total_size(sizeof(struct cgroupstats));
445 :
446 0 : rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb,
447 : size);
448 0 : if (rc < 0)
449 : goto err;
450 :
451 0 : na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS,
452 : sizeof(struct cgroupstats));
453 0 : if (na == NULL) {
454 0 : nlmsg_free(rep_skb);
455 : rc = -EMSGSIZE;
456 0 : goto err;
457 : }
458 :
459 0 : stats = nla_data(na);
460 0 : memset(stats, 0, sizeof(*stats));
461 :
462 0 : rc = cgroupstats_build(stats, f.file->f_path.dentry);
463 0 : if (rc < 0) {
464 0 : nlmsg_free(rep_skb);
465 : goto err;
466 : }
467 :
468 0 : rc = send_reply(rep_skb, info);
469 :
470 : err:
471 : fdput(f);
472 0 : return rc;
473 : }
474 :
475 0 : static int cmd_attr_register_cpumask(struct genl_info *info)
476 : {
477 : cpumask_var_t mask;
478 : int rc;
479 :
480 : if (!alloc_cpumask_var(&mask, GFP_KERNEL))
481 : return -ENOMEM;
482 0 : rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask);
483 0 : if (rc < 0)
484 : goto out;
485 0 : rc = add_del_listener(info->snd_portid, mask, REGISTER);
486 : out:
487 : free_cpumask_var(mask);
488 : return rc;
489 : }
490 :
491 0 : static int cmd_attr_deregister_cpumask(struct genl_info *info)
492 : {
493 : cpumask_var_t mask;
494 : int rc;
495 :
496 : if (!alloc_cpumask_var(&mask, GFP_KERNEL))
497 : return -ENOMEM;
498 0 : rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask);
499 0 : if (rc < 0)
500 : goto out;
501 0 : rc = add_del_listener(info->snd_portid, mask, DEREGISTER);
502 : out:
503 : free_cpumask_var(mask);
504 : return rc;
505 : }
506 :
507 : static size_t taskstats_packet_size(void)
508 : {
509 : size_t size;
510 :
511 : size = nla_total_size(sizeof(u32)) +
512 : nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
513 : #ifdef TASKSTATS_NEEDS_PADDING
514 : size += nla_total_size(0); /* Padding for alignment */
515 : #endif
516 : return size;
517 : }
518 :
519 0 : static int cmd_attr_pid(struct genl_info *info)
520 : {
521 : struct taskstats *stats;
522 : struct sk_buff *rep_skb;
523 : size_t size;
524 : u32 pid;
525 : int rc;
526 :
527 : size = taskstats_packet_size();
528 :
529 0 : rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
530 0 : if (rc < 0)
531 : return rc;
532 :
533 : rc = -EINVAL;
534 0 : pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
535 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
536 0 : if (!stats)
537 : goto err;
538 :
539 0 : rc = fill_stats_for_pid(pid, stats);
540 0 : if (rc < 0)
541 : goto err;
542 0 : return send_reply(rep_skb, info);
543 : err:
544 0 : nlmsg_free(rep_skb);
545 0 : return rc;
546 : }
547 :
548 0 : static int cmd_attr_tgid(struct genl_info *info)
549 : {
550 : struct taskstats *stats;
551 : struct sk_buff *rep_skb;
552 : size_t size;
553 : u32 tgid;
554 : int rc;
555 :
556 : size = taskstats_packet_size();
557 :
558 0 : rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
559 0 : if (rc < 0)
560 : return rc;
561 :
562 : rc = -EINVAL;
563 0 : tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
564 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
565 0 : if (!stats)
566 : goto err;
567 :
568 0 : rc = fill_stats_for_tgid(tgid, stats);
569 0 : if (rc < 0)
570 : goto err;
571 0 : return send_reply(rep_skb, info);
572 : err:
573 0 : nlmsg_free(rep_skb);
574 0 : return rc;
575 : }
576 :
577 0 : static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
578 : {
579 0 : if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK])
580 0 : return cmd_attr_register_cpumask(info);
581 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK])
582 0 : return cmd_attr_deregister_cpumask(info);
583 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_PID])
584 0 : return cmd_attr_pid(info);
585 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_TGID])
586 0 : return cmd_attr_tgid(info);
587 : else
588 : return -EINVAL;
589 : }
590 :
591 2909 : static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
592 : {
593 2909 : struct signal_struct *sig = tsk->signal;
594 : struct taskstats *stats;
595 :
596 5818 : if (sig->stats || thread_group_empty(tsk))
597 : goto ret;
598 :
599 : /* No problem if kmem_cache_zalloc() fails */
600 0 : stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
601 :
602 : spin_lock_irq(&tsk->sighand->siglock);
603 0 : if (!sig->stats) {
604 0 : sig->stats = stats;
605 : stats = NULL;
606 : }
607 : spin_unlock_irq(&tsk->sighand->siglock);
608 :
609 0 : if (stats)
610 0 : kmem_cache_free(taskstats_cache, stats);
611 : ret:
612 2909 : return sig->stats;
613 : }
614 :
615 : /* Send pid data out on exit */
616 2914 : void taskstats_exit(struct task_struct *tsk, int group_dead)
617 : {
618 : int rc;
619 : struct listener_list *listeners;
620 : struct taskstats *stats;
621 : struct sk_buff *rep_skb;
622 : size_t size;
623 : int is_thread_group;
624 :
625 2914 : if (!family_registered)
626 2914 : return;
627 :
628 : /*
629 : * Size includes space for nested attributes
630 : */
631 : size = taskstats_packet_size();
632 :
633 2909 : is_thread_group = !!taskstats_tgid_alloc(tsk);
634 2909 : if (is_thread_group) {
635 : /* PID + STATS + TGID + STATS */
636 : size = 2 * size;
637 : /* fill the tsk->signal->stats structure */
638 0 : fill_tgid_exit(tsk);
639 : }
640 :
641 : listeners = raw_cpu_ptr(&listener_array);
642 2909 : if (list_empty(&listeners->list))
643 : return;
644 :
645 0 : rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
646 0 : if (rc < 0)
647 : return;
648 :
649 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID,
650 : task_pid_nr_ns(tsk, &init_pid_ns));
651 0 : if (!stats)
652 : goto err;
653 :
654 0 : fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
655 :
656 : /*
657 : * Doesn't matter if tsk is the leader or the last group member leaving
658 : */
659 0 : if (!is_thread_group || !group_dead)
660 : goto send;
661 :
662 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID,
663 0 : task_tgid_nr_ns(tsk, &init_pid_ns));
664 0 : if (!stats)
665 : goto err;
666 :
667 0 : memcpy(stats, tsk->signal->stats, sizeof(*stats));
668 :
669 : send:
670 0 : send_cpu_listeners(rep_skb, listeners);
671 0 : return;
672 : err:
673 0 : nlmsg_free(rep_skb);
674 : }
675 :
676 : static const struct genl_ops taskstats_ops[] = {
677 : {
678 : .cmd = TASKSTATS_CMD_GET,
679 : .doit = taskstats_user_cmd,
680 : .policy = taskstats_cmd_get_policy,
681 : .flags = GENL_ADMIN_PERM,
682 : },
683 : {
684 : .cmd = CGROUPSTATS_CMD_GET,
685 : .doit = cgroupstats_user_cmd,
686 : .policy = cgroupstats_cmd_get_policy,
687 : },
688 : };
689 :
690 : /* Needed early in initialization */
691 1 : void __init taskstats_init_early(void)
692 : {
693 : unsigned int i;
694 :
695 1 : taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC);
696 2 : for_each_possible_cpu(i) {
697 : INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
698 1 : init_rwsem(&(per_cpu(listener_array, i).sem));
699 : }
700 1 : }
701 :
702 1 : static int __init taskstats_init(void)
703 : {
704 : int rc;
705 :
706 : rc = genl_register_family_with_ops(&family, taskstats_ops);
707 1 : if (rc)
708 : return rc;
709 :
710 1 : family_registered = 1;
711 1 : pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION);
712 1 : return 0;
713 : }
714 :
715 : /*
716 : * late initcall ensures initialization of statistics collection
717 : * mechanisms precedes initialization of the taskstats interface
718 : */
719 : late_initcall(taskstats_init);
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