Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0-or-later
2 : /*
3 : * taskstats.c - Export per-task statistics to userland
4 : *
5 : * Copyright (C) Shailabh Nagar, IBM Corp. 2006
6 : * (C) Balbir Singh, IBM Corp. 2006
7 : */
8 :
9 : #include <linux/kernel.h>
10 : #include <linux/taskstats_kern.h>
11 : #include <linux/tsacct_kern.h>
12 : #include <linux/delayacct.h>
13 : #include <linux/cpumask.h>
14 : #include <linux/percpu.h>
15 : #include <linux/slab.h>
16 : #include <linux/cgroupstats.h>
17 : #include <linux/cgroup.h>
18 : #include <linux/fs.h>
19 : #include <linux/file.h>
20 : #include <linux/pid_namespace.h>
21 : #include <net/genetlink.h>
22 : #include <linux/atomic.h>
23 : #include <linux/sched/cputime.h>
24 :
25 : /*
26 : * Maximum length of a cpumask that can be specified in
27 : * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute
28 : */
29 : #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS)
30 :
31 : static DEFINE_PER_CPU(__u32, taskstats_seqnum);
32 : static int family_registered;
33 : struct kmem_cache *taskstats_cache;
34 :
35 : static struct genl_family family;
36 :
37 : static const struct nla_policy taskstats_cmd_get_policy[] = {
38 : [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 },
39 : [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 },
40 : [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING },
41 : [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },};
42 :
43 : static const struct nla_policy cgroupstats_cmd_get_policy[] = {
44 : [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 },
45 : };
46 :
47 : struct listener {
48 : struct list_head list;
49 : pid_t pid;
50 : char valid;
51 : };
52 :
53 : struct listener_list {
54 : struct rw_semaphore sem;
55 : struct list_head list;
56 : };
57 : static DEFINE_PER_CPU(struct listener_list, listener_array);
58 :
59 : enum actions {
60 : REGISTER,
61 : DEREGISTER,
62 : CPU_DONT_CARE
63 : };
64 :
65 0 : static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
66 : size_t size)
67 : {
68 0 : struct sk_buff *skb;
69 0 : void *reply;
70 :
71 : /*
72 : * If new attributes are added, please revisit this allocation
73 : */
74 0 : skb = genlmsg_new(size, GFP_KERNEL);
75 0 : if (!skb)
76 : return -ENOMEM;
77 :
78 0 : if (!info) {
79 0 : int seq = this_cpu_inc_return(taskstats_seqnum) - 1;
80 :
81 0 : reply = genlmsg_put(skb, 0, seq, &family, 0, cmd);
82 : } else
83 0 : reply = genlmsg_put_reply(skb, info, &family, 0, cmd);
84 0 : if (reply == NULL) {
85 0 : nlmsg_free(skb);
86 0 : return -EINVAL;
87 : }
88 :
89 0 : *skbp = skb;
90 0 : return 0;
91 : }
92 :
93 : /*
94 : * Send taskstats data in @skb to listener with nl_pid @pid
95 : */
96 0 : static int send_reply(struct sk_buff *skb, struct genl_info *info)
97 : {
98 0 : struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
99 0 : void *reply = genlmsg_data(genlhdr);
100 :
101 0 : genlmsg_end(skb, reply);
102 :
103 0 : return genlmsg_reply(skb, info);
104 : }
105 :
106 : /*
107 : * Send taskstats data in @skb to listeners registered for @cpu's exit data
108 : */
109 0 : static void send_cpu_listeners(struct sk_buff *skb,
110 : struct listener_list *listeners)
111 : {
112 0 : struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
113 0 : struct listener *s, *tmp;
114 0 : struct sk_buff *skb_next, *skb_cur = skb;
115 0 : void *reply = genlmsg_data(genlhdr);
116 0 : int rc, delcount = 0;
117 :
118 0 : genlmsg_end(skb, reply);
119 :
120 0 : rc = 0;
121 0 : down_read(&listeners->sem);
122 0 : list_for_each_entry(s, &listeners->list, list) {
123 0 : skb_next = NULL;
124 0 : if (!list_is_last(&s->list, &listeners->list)) {
125 0 : skb_next = skb_clone(skb_cur, GFP_KERNEL);
126 0 : if (!skb_next)
127 : break;
128 : }
129 0 : rc = genlmsg_unicast(&init_net, skb_cur, s->pid);
130 0 : if (rc == -ECONNREFUSED) {
131 0 : s->valid = 0;
132 0 : delcount++;
133 : }
134 0 : skb_cur = skb_next;
135 : }
136 0 : up_read(&listeners->sem);
137 :
138 0 : if (skb_cur)
139 0 : nlmsg_free(skb_cur);
140 :
141 0 : if (!delcount)
142 : return;
143 :
144 : /* Delete invalidated entries */
145 0 : down_write(&listeners->sem);
146 0 : list_for_each_entry_safe(s, tmp, &listeners->list, list) {
147 0 : if (!s->valid) {
148 0 : list_del(&s->list);
149 0 : kfree(s);
150 : }
151 : }
152 0 : up_write(&listeners->sem);
153 : }
154 :
155 0 : static void fill_stats(struct user_namespace *user_ns,
156 : struct pid_namespace *pid_ns,
157 : struct task_struct *tsk, struct taskstats *stats)
158 : {
159 0 : memset(stats, 0, sizeof(*stats));
160 : /*
161 : * Each accounting subsystem adds calls to its functions to
162 : * fill in relevant parts of struct taskstsats as follows
163 : *
164 : * per-task-foo(stats, tsk);
165 : */
166 :
167 0 : delayacct_add_tsk(stats, tsk);
168 :
169 : /* fill in basic acct fields */
170 0 : stats->version = TASKSTATS_VERSION;
171 0 : stats->nvcsw = tsk->nvcsw;
172 0 : stats->nivcsw = tsk->nivcsw;
173 0 : bacct_add_tsk(user_ns, pid_ns, stats, tsk);
174 :
175 : /* fill in extended acct fields */
176 0 : xacct_add_tsk(stats, tsk);
177 0 : }
178 :
179 0 : static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
180 : {
181 0 : struct task_struct *tsk;
182 :
183 0 : tsk = find_get_task_by_vpid(pid);
184 0 : if (!tsk)
185 : return -ESRCH;
186 0 : fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats);
187 0 : put_task_struct(tsk);
188 0 : return 0;
189 : }
190 :
191 0 : static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
192 : {
193 0 : struct task_struct *tsk, *first;
194 0 : unsigned long flags;
195 0 : int rc = -ESRCH;
196 0 : u64 delta, utime, stime;
197 0 : u64 start_time;
198 :
199 : /*
200 : * Add additional stats from live tasks except zombie thread group
201 : * leaders who are already counted with the dead tasks
202 : */
203 0 : rcu_read_lock();
204 0 : first = find_task_by_vpid(tgid);
205 :
206 0 : if (!first || !lock_task_sighand(first, &flags))
207 0 : goto out;
208 :
209 0 : if (first->signal->stats)
210 0 : memcpy(stats, first->signal->stats, sizeof(*stats));
211 : else
212 0 : memset(stats, 0, sizeof(*stats));
213 :
214 0 : tsk = first;
215 0 : start_time = ktime_get_ns();
216 0 : do {
217 0 : if (tsk->exit_state)
218 0 : continue;
219 : /*
220 : * Accounting subsystem can call its functions here to
221 : * fill in relevant parts of struct taskstsats as follows
222 : *
223 : * per-task-foo(stats, tsk);
224 : */
225 0 : delayacct_add_tsk(stats, tsk);
226 :
227 : /* calculate task elapsed time in nsec */
228 0 : delta = start_time - tsk->start_time;
229 : /* Convert to micro seconds */
230 0 : do_div(delta, NSEC_PER_USEC);
231 0 : stats->ac_etime += delta;
232 :
233 0 : task_cputime(tsk, &utime, &stime);
234 0 : stats->ac_utime += div_u64(utime, NSEC_PER_USEC);
235 0 : stats->ac_stime += div_u64(stime, NSEC_PER_USEC);
236 :
237 0 : stats->nvcsw += tsk->nvcsw;
238 0 : stats->nivcsw += tsk->nivcsw;
239 0 : } while_each_thread(first, tsk);
240 :
241 0 : unlock_task_sighand(first, &flags);
242 0 : rc = 0;
243 0 : out:
244 0 : rcu_read_unlock();
245 :
246 0 : stats->version = TASKSTATS_VERSION;
247 : /*
248 : * Accounting subsystems can also add calls here to modify
249 : * fields of taskstats.
250 : */
251 0 : return rc;
252 : }
253 :
254 2 : static void fill_tgid_exit(struct task_struct *tsk)
255 : {
256 2 : unsigned long flags;
257 :
258 2 : spin_lock_irqsave(&tsk->sighand->siglock, flags);
259 2 : if (!tsk->signal->stats)
260 0 : goto ret;
261 :
262 : /*
263 : * Each accounting subsystem calls its functions here to
264 : * accumalate its per-task stats for tsk, into the per-tgid structure
265 : *
266 : * per-task-foo(tsk->signal->stats, tsk);
267 : */
268 2 : delayacct_add_tsk(tsk->signal->stats, tsk);
269 2 : ret:
270 2 : spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
271 2 : return;
272 : }
273 :
274 0 : static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd)
275 : {
276 0 : struct listener_list *listeners;
277 0 : struct listener *s, *tmp, *s2;
278 0 : unsigned int cpu;
279 0 : int ret = 0;
280 :
281 0 : if (!cpumask_subset(mask, cpu_possible_mask))
282 : return -EINVAL;
283 :
284 0 : if (current_user_ns() != &init_user_ns)
285 : return -EINVAL;
286 :
287 0 : if (task_active_pid_ns(current) != &init_pid_ns)
288 : return -EINVAL;
289 :
290 0 : if (isadd == REGISTER) {
291 0 : for_each_cpu(cpu, mask) {
292 0 : s = kmalloc_node(sizeof(struct listener),
293 : GFP_KERNEL, cpu_to_node(cpu));
294 0 : if (!s) {
295 0 : ret = -ENOMEM;
296 0 : goto cleanup;
297 : }
298 0 : s->pid = pid;
299 0 : s->valid = 1;
300 :
301 0 : listeners = &per_cpu(listener_array, cpu);
302 0 : down_write(&listeners->sem);
303 0 : list_for_each_entry(s2, &listeners->list, list) {
304 0 : if (s2->pid == pid && s2->valid)
305 0 : goto exists;
306 : }
307 0 : list_add(&s->list, &listeners->list);
308 0 : s = NULL;
309 0 : exists:
310 0 : up_write(&listeners->sem);
311 0 : kfree(s); /* nop if NULL */
312 : }
313 : return 0;
314 : }
315 :
316 : /* Deregister or cleanup */
317 0 : cleanup:
318 0 : for_each_cpu(cpu, mask) {
319 0 : listeners = &per_cpu(listener_array, cpu);
320 0 : down_write(&listeners->sem);
321 0 : list_for_each_entry_safe(s, tmp, &listeners->list, list) {
322 0 : if (s->pid == pid) {
323 0 : list_del(&s->list);
324 0 : kfree(s);
325 0 : break;
326 : }
327 : }
328 0 : up_write(&listeners->sem);
329 : }
330 : return ret;
331 : }
332 :
333 0 : static int parse(struct nlattr *na, struct cpumask *mask)
334 : {
335 0 : char *data;
336 0 : int len;
337 0 : int ret;
338 :
339 0 : if (na == NULL)
340 : return 1;
341 0 : len = nla_len(na);
342 0 : if (len > TASKSTATS_CPUMASK_MAXLEN)
343 : return -E2BIG;
344 0 : if (len < 1)
345 : return -EINVAL;
346 0 : data = kmalloc(len, GFP_KERNEL);
347 0 : if (!data)
348 : return -ENOMEM;
349 0 : nla_strscpy(data, na, len);
350 0 : ret = cpulist_parse(data, mask);
351 0 : kfree(data);
352 0 : return ret;
353 : }
354 :
355 0 : static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
356 : {
357 0 : struct nlattr *na, *ret;
358 0 : int aggr;
359 :
360 0 : aggr = (type == TASKSTATS_TYPE_PID)
361 : ? TASKSTATS_TYPE_AGGR_PID
362 0 : : TASKSTATS_TYPE_AGGR_TGID;
363 :
364 0 : na = nla_nest_start_noflag(skb, aggr);
365 0 : if (!na)
366 0 : goto err;
367 :
368 0 : if (nla_put(skb, type, sizeof(pid), &pid) < 0) {
369 0 : nla_nest_cancel(skb, na);
370 0 : goto err;
371 : }
372 0 : ret = nla_reserve_64bit(skb, TASKSTATS_TYPE_STATS,
373 : sizeof(struct taskstats), TASKSTATS_TYPE_NULL);
374 0 : if (!ret) {
375 0 : nla_nest_cancel(skb, na);
376 0 : goto err;
377 : }
378 0 : nla_nest_end(skb, na);
379 :
380 0 : return nla_data(ret);
381 : err:
382 : return NULL;
383 : }
384 :
385 0 : static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
386 : {
387 0 : int rc = 0;
388 0 : struct sk_buff *rep_skb;
389 0 : struct cgroupstats *stats;
390 0 : struct nlattr *na;
391 0 : size_t size;
392 0 : u32 fd;
393 0 : struct fd f;
394 :
395 0 : na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
396 0 : if (!na)
397 : return -EINVAL;
398 :
399 0 : fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
400 0 : f = fdget(fd);
401 0 : if (!f.file)
402 : return 0;
403 :
404 0 : size = nla_total_size(sizeof(struct cgroupstats));
405 :
406 0 : rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb,
407 : size);
408 0 : if (rc < 0)
409 0 : goto err;
410 :
411 0 : na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS,
412 : sizeof(struct cgroupstats));
413 0 : if (na == NULL) {
414 0 : nlmsg_free(rep_skb);
415 0 : rc = -EMSGSIZE;
416 0 : goto err;
417 : }
418 :
419 0 : stats = nla_data(na);
420 0 : memset(stats, 0, sizeof(*stats));
421 :
422 0 : rc = cgroupstats_build(stats, f.file->f_path.dentry);
423 0 : if (rc < 0) {
424 0 : nlmsg_free(rep_skb);
425 0 : goto err;
426 : }
427 :
428 0 : rc = send_reply(rep_skb, info);
429 :
430 0 : err:
431 0 : fdput(f);
432 0 : return rc;
433 : }
434 :
435 0 : static int cmd_attr_register_cpumask(struct genl_info *info)
436 : {
437 0 : cpumask_var_t mask;
438 0 : int rc;
439 :
440 0 : if (!alloc_cpumask_var(&mask, GFP_KERNEL))
441 : return -ENOMEM;
442 0 : rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask);
443 0 : if (rc < 0)
444 0 : goto out;
445 0 : rc = add_del_listener(info->snd_portid, mask, REGISTER);
446 0 : out:
447 0 : free_cpumask_var(mask);
448 0 : return rc;
449 : }
450 :
451 0 : static int cmd_attr_deregister_cpumask(struct genl_info *info)
452 : {
453 0 : cpumask_var_t mask;
454 0 : int rc;
455 :
456 0 : if (!alloc_cpumask_var(&mask, GFP_KERNEL))
457 : return -ENOMEM;
458 0 : rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask);
459 0 : if (rc < 0)
460 0 : goto out;
461 0 : rc = add_del_listener(info->snd_portid, mask, DEREGISTER);
462 0 : out:
463 0 : free_cpumask_var(mask);
464 0 : return rc;
465 : }
466 :
467 1107 : static size_t taskstats_packet_size(void)
468 : {
469 1107 : size_t size;
470 :
471 1107 : size = nla_total_size(sizeof(u32)) +
472 1107 : nla_total_size_64bit(sizeof(struct taskstats)) +
473 1107 : nla_total_size(0);
474 :
475 1107 : return size;
476 : }
477 :
478 0 : static int cmd_attr_pid(struct genl_info *info)
479 : {
480 0 : struct taskstats *stats;
481 0 : struct sk_buff *rep_skb;
482 0 : size_t size;
483 0 : u32 pid;
484 0 : int rc;
485 :
486 0 : size = taskstats_packet_size();
487 :
488 0 : rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
489 0 : if (rc < 0)
490 : return rc;
491 :
492 0 : rc = -EINVAL;
493 0 : pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
494 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
495 0 : if (!stats)
496 0 : goto err;
497 :
498 0 : rc = fill_stats_for_pid(pid, stats);
499 0 : if (rc < 0)
500 0 : goto err;
501 0 : return send_reply(rep_skb, info);
502 0 : err:
503 0 : nlmsg_free(rep_skb);
504 0 : return rc;
505 : }
506 :
507 0 : static int cmd_attr_tgid(struct genl_info *info)
508 : {
509 0 : struct taskstats *stats;
510 0 : struct sk_buff *rep_skb;
511 0 : size_t size;
512 0 : u32 tgid;
513 0 : int rc;
514 :
515 0 : size = taskstats_packet_size();
516 :
517 0 : rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
518 0 : if (rc < 0)
519 : return rc;
520 :
521 0 : rc = -EINVAL;
522 0 : tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
523 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
524 0 : if (!stats)
525 0 : goto err;
526 :
527 0 : rc = fill_stats_for_tgid(tgid, stats);
528 0 : if (rc < 0)
529 0 : goto err;
530 0 : return send_reply(rep_skb, info);
531 0 : err:
532 0 : nlmsg_free(rep_skb);
533 0 : return rc;
534 : }
535 :
536 0 : static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
537 : {
538 0 : if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK])
539 0 : return cmd_attr_register_cpumask(info);
540 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK])
541 0 : return cmd_attr_deregister_cpumask(info);
542 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_PID])
543 0 : return cmd_attr_pid(info);
544 0 : else if (info->attrs[TASKSTATS_CMD_ATTR_TGID])
545 0 : return cmd_attr_tgid(info);
546 : else
547 : return -EINVAL;
548 : }
549 :
550 1107 : static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
551 : {
552 1107 : struct signal_struct *sig = tsk->signal;
553 1107 : struct taskstats *stats_new, *stats;
554 :
555 : /* Pairs with smp_store_release() below. */
556 1107 : stats = smp_load_acquire(&sig->stats);
557 1107 : if (stats || thread_group_empty(tsk))
558 : return stats;
559 :
560 : /* No problem if kmem_cache_zalloc() fails */
561 1 : stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
562 :
563 1 : spin_lock_irq(&tsk->sighand->siglock);
564 1 : stats = sig->stats;
565 1 : if (!stats) {
566 : /*
567 : * Pairs with smp_store_release() above and order the
568 : * kmem_cache_zalloc().
569 : */
570 1 : smp_store_release(&sig->stats, stats_new);
571 1 : stats = stats_new;
572 1 : stats_new = NULL;
573 : }
574 1 : spin_unlock_irq(&tsk->sighand->siglock);
575 :
576 1 : if (stats_new)
577 0 : kmem_cache_free(taskstats_cache, stats_new);
578 :
579 : return stats;
580 : }
581 :
582 : /* Send pid data out on exit */
583 1107 : void taskstats_exit(struct task_struct *tsk, int group_dead)
584 : {
585 1107 : int rc;
586 1107 : struct listener_list *listeners;
587 1107 : struct taskstats *stats;
588 1107 : struct sk_buff *rep_skb;
589 1107 : size_t size;
590 1107 : int is_thread_group;
591 :
592 1107 : if (!family_registered)
593 1107 : return;
594 :
595 : /*
596 : * Size includes space for nested attributes
597 : */
598 1107 : size = taskstats_packet_size();
599 :
600 1107 : is_thread_group = !!taskstats_tgid_alloc(tsk);
601 1107 : if (is_thread_group) {
602 : /* PID + STATS + TGID + STATS */
603 2 : size = 2 * size;
604 : /* fill the tsk->signal->stats structure */
605 2 : fill_tgid_exit(tsk);
606 : }
607 :
608 1107 : listeners = raw_cpu_ptr(&listener_array);
609 1107 : if (list_empty(&listeners->list))
610 : return;
611 :
612 0 : rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
613 0 : if (rc < 0)
614 : return;
615 :
616 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID,
617 0 : task_pid_nr_ns(tsk, &init_pid_ns));
618 0 : if (!stats)
619 0 : goto err;
620 :
621 0 : fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
622 :
623 : /*
624 : * Doesn't matter if tsk is the leader or the last group member leaving
625 : */
626 0 : if (!is_thread_group || !group_dead)
627 0 : goto send;
628 :
629 0 : stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID,
630 0 : task_tgid_nr_ns(tsk, &init_pid_ns));
631 0 : if (!stats)
632 0 : goto err;
633 :
634 0 : memcpy(stats, tsk->signal->stats, sizeof(*stats));
635 :
636 0 : send:
637 0 : send_cpu_listeners(rep_skb, listeners);
638 0 : return;
639 0 : err:
640 0 : nlmsg_free(rep_skb);
641 : }
642 :
643 : static const struct genl_ops taskstats_ops[] = {
644 : {
645 : .cmd = TASKSTATS_CMD_GET,
646 : .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
647 : .doit = taskstats_user_cmd,
648 : .policy = taskstats_cmd_get_policy,
649 : .maxattr = ARRAY_SIZE(taskstats_cmd_get_policy) - 1,
650 : .flags = GENL_ADMIN_PERM,
651 : },
652 : {
653 : .cmd = CGROUPSTATS_CMD_GET,
654 : .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
655 : .doit = cgroupstats_user_cmd,
656 : .policy = cgroupstats_cmd_get_policy,
657 : .maxattr = ARRAY_SIZE(cgroupstats_cmd_get_policy) - 1,
658 : },
659 : };
660 :
661 : static struct genl_family family __ro_after_init = {
662 : .name = TASKSTATS_GENL_NAME,
663 : .version = TASKSTATS_GENL_VERSION,
664 : .module = THIS_MODULE,
665 : .ops = taskstats_ops,
666 : .n_ops = ARRAY_SIZE(taskstats_ops),
667 : };
668 :
669 : /* Needed early in initialization */
670 1 : void __init taskstats_init_early(void)
671 : {
672 1 : unsigned int i;
673 :
674 1 : taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC);
675 6 : for_each_possible_cpu(i) {
676 4 : INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
677 5 : init_rwsem(&(per_cpu(listener_array, i).sem));
678 : }
679 1 : }
680 :
681 1 : static int __init taskstats_init(void)
682 : {
683 1 : int rc;
684 :
685 1 : rc = genl_register_family(&family);
686 1 : if (rc)
687 : return rc;
688 :
689 1 : family_registered = 1;
690 1 : pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION);
691 1 : return 0;
692 : }
693 :
694 : /*
695 : * late initcall ensures initialization of statistics collection
696 : * mechanisms precedes initialization of the taskstats interface
697 : */
698 : late_initcall(taskstats_init);
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