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/acct.h> |
13 | #include <linux/delayacct.h> |
14 | #include <linux/cpumask.h> |
15 | #include <linux/percpu.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/cgroupstats.h> |
18 | #include <linux/cgroup.h> |
19 | #include <linux/fs.h> |
20 | #include <linux/file.h> |
21 | #include <linux/pid_namespace.h> |
22 | #include <net/genetlink.h> |
23 | #include <linux/atomic.h> |
24 | #include <linux/sched/cputime.h> |
25 | |
26 | /* |
27 | * Maximum length of a cpumask that can be specified in |
28 | * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute |
29 | */ |
30 | #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS) |
31 | |
32 | static DEFINE_PER_CPU(__u32, taskstats_seqnum); |
33 | static int family_registered; |
34 | struct kmem_cache *taskstats_cache; |
35 | |
36 | static struct genl_family family; |
37 | |
38 | static const struct nla_policy taskstats_cmd_get_policy[] = { |
39 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
40 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, |
41 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
42 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; |
43 | |
44 | static const struct nla_policy cgroupstats_cmd_get_policy[] = { |
45 | [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 }, |
46 | }; |
47 | |
48 | struct listener { |
49 | struct list_head list; |
50 | pid_t pid; |
51 | char valid; |
52 | }; |
53 | |
54 | struct listener_list { |
55 | struct rw_semaphore sem; |
56 | struct list_head list; |
57 | }; |
58 | static DEFINE_PER_CPU(struct listener_list, listener_array); |
59 | |
60 | enum actions { |
61 | REGISTER, |
62 | DEREGISTER, |
63 | CPU_DONT_CARE |
64 | }; |
65 | |
66 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, |
67 | size_t size) |
68 | { |
69 | struct sk_buff *skb; |
70 | void *reply; |
71 | |
72 | /* |
73 | * If new attributes are added, please revisit this allocation |
74 | */ |
75 | skb = genlmsg_new(payload: size, GFP_KERNEL); |
76 | if (!skb) |
77 | return -ENOMEM; |
78 | |
79 | if (!info) { |
80 | int seq = this_cpu_inc_return(taskstats_seqnum) - 1; |
81 | |
82 | reply = genlmsg_put(skb, portid: 0, seq, family: &family, flags: 0, cmd); |
83 | } else |
84 | reply = genlmsg_put_reply(skb, info, family: &family, flags: 0, cmd); |
85 | if (reply == NULL) { |
86 | nlmsg_free(skb); |
87 | return -EINVAL; |
88 | } |
89 | |
90 | *skbp = skb; |
91 | return 0; |
92 | } |
93 | |
94 | /* |
95 | * Send taskstats data in @skb to listener with nl_pid @pid |
96 | */ |
97 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
98 | { |
99 | struct genlmsghdr *genlhdr = nlmsg_data(nlh: nlmsg_hdr(skb)); |
100 | void *reply = genlmsg_data(gnlh: genlhdr); |
101 | |
102 | genlmsg_end(skb, hdr: reply); |
103 | |
104 | return genlmsg_reply(skb, info); |
105 | } |
106 | |
107 | /* |
108 | * Send taskstats data in @skb to listeners registered for @cpu's exit data |
109 | */ |
110 | static void send_cpu_listeners(struct sk_buff *skb, |
111 | struct listener_list *listeners) |
112 | { |
113 | struct genlmsghdr *genlhdr = nlmsg_data(nlh: nlmsg_hdr(skb)); |
114 | struct listener *s, *tmp; |
115 | struct sk_buff *skb_next, *skb_cur = skb; |
116 | void *reply = genlmsg_data(gnlh: genlhdr); |
117 | int delcount = 0; |
118 | |
119 | genlmsg_end(skb, hdr: reply); |
120 | |
121 | down_read(sem: &listeners->sem); |
122 | list_for_each_entry(s, &listeners->list, list) { |
123 | int rc; |
124 | |
125 | skb_next = NULL; |
126 | if (!list_is_last(list: &s->list, head: &listeners->list)) { |
127 | skb_next = skb_clone(skb: skb_cur, GFP_KERNEL); |
128 | if (!skb_next) |
129 | break; |
130 | } |
131 | rc = genlmsg_unicast(net: &init_net, skb: skb_cur, portid: s->pid); |
132 | if (rc == -ECONNREFUSED) { |
133 | s->valid = 0; |
134 | delcount++; |
135 | } |
136 | skb_cur = skb_next; |
137 | } |
138 | up_read(sem: &listeners->sem); |
139 | |
140 | if (skb_cur) |
141 | nlmsg_free(skb: skb_cur); |
142 | |
143 | if (!delcount) |
144 | return; |
145 | |
146 | /* Delete invalidated entries */ |
147 | down_write(sem: &listeners->sem); |
148 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
149 | if (!s->valid) { |
150 | list_del(entry: &s->list); |
151 | kfree(objp: s); |
152 | } |
153 | } |
154 | up_write(sem: &listeners->sem); |
155 | } |
156 | |
157 | static void exe_add_tsk(struct taskstats *stats, struct task_struct *tsk) |
158 | { |
159 | /* No idea if I'm allowed to access that here, now. */ |
160 | struct file *exe_file = get_task_exe_file(task: tsk); |
161 | |
162 | if (exe_file) { |
163 | /* Following cp_new_stat64() in stat.c . */ |
164 | stats->ac_exe_dev = |
165 | huge_encode_dev(dev: exe_file->f_inode->i_sb->s_dev); |
166 | stats->ac_exe_inode = exe_file->f_inode->i_ino; |
167 | fput(exe_file); |
168 | } else { |
169 | stats->ac_exe_dev = 0; |
170 | stats->ac_exe_inode = 0; |
171 | } |
172 | } |
173 | |
174 | static void fill_stats(struct user_namespace *user_ns, |
175 | struct pid_namespace *pid_ns, |
176 | struct task_struct *tsk, struct taskstats *stats) |
177 | { |
178 | memset(stats, 0, sizeof(*stats)); |
179 | /* |
180 | * Each accounting subsystem adds calls to its functions to |
181 | * fill in relevant parts of struct taskstsats as follows |
182 | * |
183 | * per-task-foo(stats, tsk); |
184 | */ |
185 | |
186 | delayacct_add_tsk(stats, tsk); |
187 | |
188 | /* fill in basic acct fields */ |
189 | stats->version = TASKSTATS_VERSION; |
190 | stats->nvcsw = tsk->nvcsw; |
191 | stats->nivcsw = tsk->nivcsw; |
192 | bacct_add_tsk(user_ns, pid_ns, stats, tsk); |
193 | |
194 | /* fill in extended acct fields */ |
195 | xacct_add_tsk(stats, p: tsk); |
196 | |
197 | /* add executable info */ |
198 | exe_add_tsk(stats, tsk); |
199 | } |
200 | |
201 | static int fill_stats_for_pid(pid_t pid, struct taskstats *stats) |
202 | { |
203 | struct task_struct *tsk; |
204 | |
205 | tsk = find_get_task_by_vpid(nr: pid); |
206 | if (!tsk) |
207 | return -ESRCH; |
208 | fill_stats(current_user_ns(), pid_ns: task_active_pid_ns(current), tsk, stats); |
209 | put_task_struct(t: tsk); |
210 | return 0; |
211 | } |
212 | |
213 | static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) |
214 | { |
215 | struct task_struct *tsk, *first; |
216 | unsigned long flags; |
217 | int rc = -ESRCH; |
218 | u64 delta, utime, stime; |
219 | u64 start_time; |
220 | |
221 | /* |
222 | * Add additional stats from live tasks except zombie thread group |
223 | * leaders who are already counted with the dead tasks |
224 | */ |
225 | rcu_read_lock(); |
226 | first = find_task_by_vpid(nr: tgid); |
227 | |
228 | if (!first || !lock_task_sighand(task: first, flags: &flags)) |
229 | goto out; |
230 | |
231 | if (first->signal->stats) |
232 | memcpy(stats, first->signal->stats, sizeof(*stats)); |
233 | else |
234 | memset(stats, 0, sizeof(*stats)); |
235 | |
236 | start_time = ktime_get_ns(); |
237 | for_each_thread(first, tsk) { |
238 | if (tsk->exit_state) |
239 | continue; |
240 | /* |
241 | * Accounting subsystem can call its functions here to |
242 | * fill in relevant parts of struct taskstsats as follows |
243 | * |
244 | * per-task-foo(stats, tsk); |
245 | */ |
246 | delayacct_add_tsk(stats, tsk); |
247 | |
248 | /* calculate task elapsed time in nsec */ |
249 | delta = start_time - tsk->start_time; |
250 | /* Convert to micro seconds */ |
251 | do_div(delta, NSEC_PER_USEC); |
252 | stats->ac_etime += delta; |
253 | |
254 | task_cputime(t: tsk, utime: &utime, stime: &stime); |
255 | stats->ac_utime += div_u64(dividend: utime, NSEC_PER_USEC); |
256 | stats->ac_stime += div_u64(dividend: stime, NSEC_PER_USEC); |
257 | |
258 | stats->nvcsw += tsk->nvcsw; |
259 | stats->nivcsw += tsk->nivcsw; |
260 | } |
261 | |
262 | unlock_task_sighand(task: first, flags: &flags); |
263 | rc = 0; |
264 | out: |
265 | rcu_read_unlock(); |
266 | |
267 | stats->version = TASKSTATS_VERSION; |
268 | /* |
269 | * Accounting subsystems can also add calls here to modify |
270 | * fields of taskstats. |
271 | */ |
272 | return rc; |
273 | } |
274 | |
275 | static void fill_tgid_exit(struct task_struct *tsk) |
276 | { |
277 | unsigned long flags; |
278 | |
279 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
280 | if (!tsk->signal->stats) |
281 | goto ret; |
282 | |
283 | /* |
284 | * Each accounting subsystem calls its functions here to |
285 | * accumalate its per-task stats for tsk, into the per-tgid structure |
286 | * |
287 | * per-task-foo(tsk->signal->stats, tsk); |
288 | */ |
289 | delayacct_add_tsk(tsk->signal->stats, tsk); |
290 | ret: |
291 | spin_unlock_irqrestore(lock: &tsk->sighand->siglock, flags); |
292 | return; |
293 | } |
294 | |
295 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
296 | { |
297 | struct listener_list *listeners; |
298 | struct listener *s, *tmp, *s2; |
299 | unsigned int cpu; |
300 | int ret = 0; |
301 | |
302 | if (!cpumask_subset(src1p: mask, cpu_possible_mask)) |
303 | return -EINVAL; |
304 | |
305 | if (current_user_ns() != &init_user_ns) |
306 | return -EINVAL; |
307 | |
308 | if (task_active_pid_ns(current) != &init_pid_ns) |
309 | return -EINVAL; |
310 | |
311 | if (isadd == REGISTER) { |
312 | for_each_cpu(cpu, mask) { |
313 | s = kmalloc_node(size: sizeof(struct listener), |
314 | GFP_KERNEL, cpu_to_node(cpu)); |
315 | if (!s) { |
316 | ret = -ENOMEM; |
317 | goto cleanup; |
318 | } |
319 | s->pid = pid; |
320 | s->valid = 1; |
321 | |
322 | listeners = &per_cpu(listener_array, cpu); |
323 | down_write(sem: &listeners->sem); |
324 | list_for_each_entry(s2, &listeners->list, list) { |
325 | if (s2->pid == pid && s2->valid) |
326 | goto exists; |
327 | } |
328 | list_add(new: &s->list, head: &listeners->list); |
329 | s = NULL; |
330 | exists: |
331 | up_write(sem: &listeners->sem); |
332 | kfree(objp: s); /* nop if NULL */ |
333 | } |
334 | return 0; |
335 | } |
336 | |
337 | /* Deregister or cleanup */ |
338 | cleanup: |
339 | for_each_cpu(cpu, mask) { |
340 | listeners = &per_cpu(listener_array, cpu); |
341 | down_write(sem: &listeners->sem); |
342 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
343 | if (s->pid == pid) { |
344 | list_del(entry: &s->list); |
345 | kfree(objp: s); |
346 | break; |
347 | } |
348 | } |
349 | up_write(sem: &listeners->sem); |
350 | } |
351 | return ret; |
352 | } |
353 | |
354 | static int parse(struct nlattr *na, struct cpumask *mask) |
355 | { |
356 | char *data; |
357 | int len; |
358 | int ret; |
359 | |
360 | if (na == NULL) |
361 | return 1; |
362 | len = nla_len(nla: na); |
363 | if (len > TASKSTATS_CPUMASK_MAXLEN) |
364 | return -E2BIG; |
365 | if (len < 1) |
366 | return -EINVAL; |
367 | data = kmalloc(size: len, GFP_KERNEL); |
368 | if (!data) |
369 | return -ENOMEM; |
370 | nla_strscpy(dst: data, nla: na, dstsize: len); |
371 | ret = cpulist_parse(buf: data, dstp: mask); |
372 | kfree(objp: data); |
373 | return ret; |
374 | } |
375 | |
376 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
377 | { |
378 | struct nlattr *na, *ret; |
379 | int aggr; |
380 | |
381 | aggr = (type == TASKSTATS_TYPE_PID) |
382 | ? TASKSTATS_TYPE_AGGR_PID |
383 | : TASKSTATS_TYPE_AGGR_TGID; |
384 | |
385 | na = nla_nest_start_noflag(skb, attrtype: aggr); |
386 | if (!na) |
387 | goto err; |
388 | |
389 | if (nla_put(skb, attrtype: type, attrlen: sizeof(pid), data: &pid) < 0) { |
390 | nla_nest_cancel(skb, start: na); |
391 | goto err; |
392 | } |
393 | ret = nla_reserve_64bit(skb, attrtype: TASKSTATS_TYPE_STATS, |
394 | attrlen: sizeof(struct taskstats), padattr: TASKSTATS_TYPE_NULL); |
395 | if (!ret) { |
396 | nla_nest_cancel(skb, start: na); |
397 | goto err; |
398 | } |
399 | nla_nest_end(skb, start: na); |
400 | |
401 | return nla_data(nla: ret); |
402 | err: |
403 | return NULL; |
404 | } |
405 | |
406 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
407 | { |
408 | int rc = 0; |
409 | struct sk_buff *rep_skb; |
410 | struct cgroupstats *stats; |
411 | struct nlattr *na; |
412 | size_t size; |
413 | u32 fd; |
414 | struct fd f; |
415 | |
416 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; |
417 | if (!na) |
418 | return -EINVAL; |
419 | |
420 | fd = nla_get_u32(nla: info->attrs[CGROUPSTATS_CMD_ATTR_FD]); |
421 | f = fdget(fd); |
422 | if (!f.file) |
423 | return 0; |
424 | |
425 | size = nla_total_size(payload: sizeof(struct cgroupstats)); |
426 | |
427 | rc = prepare_reply(info, cmd: CGROUPSTATS_CMD_NEW, skbp: &rep_skb, |
428 | size); |
429 | if (rc < 0) |
430 | goto err; |
431 | |
432 | na = nla_reserve(skb: rep_skb, attrtype: CGROUPSTATS_TYPE_CGROUP_STATS, |
433 | attrlen: sizeof(struct cgroupstats)); |
434 | if (na == NULL) { |
435 | nlmsg_free(skb: rep_skb); |
436 | rc = -EMSGSIZE; |
437 | goto err; |
438 | } |
439 | |
440 | stats = nla_data(nla: na); |
441 | memset(stats, 0, sizeof(*stats)); |
442 | |
443 | rc = cgroupstats_build(stats, dentry: f.file->f_path.dentry); |
444 | if (rc < 0) { |
445 | nlmsg_free(skb: rep_skb); |
446 | goto err; |
447 | } |
448 | |
449 | rc = send_reply(skb: rep_skb, info); |
450 | |
451 | err: |
452 | fdput(fd: f); |
453 | return rc; |
454 | } |
455 | |
456 | static int cmd_attr_register_cpumask(struct genl_info *info) |
457 | { |
458 | cpumask_var_t mask; |
459 | int rc; |
460 | |
461 | if (!alloc_cpumask_var(mask: &mask, GFP_KERNEL)) |
462 | return -ENOMEM; |
463 | rc = parse(na: info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
464 | if (rc < 0) |
465 | goto out; |
466 | rc = add_del_listener(pid: info->snd_portid, mask, isadd: REGISTER); |
467 | out: |
468 | free_cpumask_var(mask); |
469 | return rc; |
470 | } |
471 | |
472 | static int cmd_attr_deregister_cpumask(struct genl_info *info) |
473 | { |
474 | cpumask_var_t mask; |
475 | int rc; |
476 | |
477 | if (!alloc_cpumask_var(mask: &mask, GFP_KERNEL)) |
478 | return -ENOMEM; |
479 | rc = parse(na: info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
480 | if (rc < 0) |
481 | goto out; |
482 | rc = add_del_listener(pid: info->snd_portid, mask, isadd: DEREGISTER); |
483 | out: |
484 | free_cpumask_var(mask); |
485 | return rc; |
486 | } |
487 | |
488 | static size_t taskstats_packet_size(void) |
489 | { |
490 | size_t size; |
491 | |
492 | size = nla_total_size(payload: sizeof(u32)) + |
493 | nla_total_size_64bit(payload: sizeof(struct taskstats)) + |
494 | nla_total_size(payload: 0); |
495 | |
496 | return size; |
497 | } |
498 | |
499 | static int cmd_attr_pid(struct genl_info *info) |
500 | { |
501 | struct taskstats *stats; |
502 | struct sk_buff *rep_skb; |
503 | size_t size; |
504 | u32 pid; |
505 | int rc; |
506 | |
507 | size = taskstats_packet_size(); |
508 | |
509 | rc = prepare_reply(info, cmd: TASKSTATS_CMD_NEW, skbp: &rep_skb, size); |
510 | if (rc < 0) |
511 | return rc; |
512 | |
513 | rc = -EINVAL; |
514 | pid = nla_get_u32(nla: info->attrs[TASKSTATS_CMD_ATTR_PID]); |
515 | stats = mk_reply(skb: rep_skb, type: TASKSTATS_TYPE_PID, pid); |
516 | if (!stats) |
517 | goto err; |
518 | |
519 | rc = fill_stats_for_pid(pid, stats); |
520 | if (rc < 0) |
521 | goto err; |
522 | return send_reply(skb: rep_skb, info); |
523 | err: |
524 | nlmsg_free(skb: rep_skb); |
525 | return rc; |
526 | } |
527 | |
528 | static int cmd_attr_tgid(struct genl_info *info) |
529 | { |
530 | struct taskstats *stats; |
531 | struct sk_buff *rep_skb; |
532 | size_t size; |
533 | u32 tgid; |
534 | int rc; |
535 | |
536 | size = taskstats_packet_size(); |
537 | |
538 | rc = prepare_reply(info, cmd: TASKSTATS_CMD_NEW, skbp: &rep_skb, size); |
539 | if (rc < 0) |
540 | return rc; |
541 | |
542 | rc = -EINVAL; |
543 | tgid = nla_get_u32(nla: info->attrs[TASKSTATS_CMD_ATTR_TGID]); |
544 | stats = mk_reply(skb: rep_skb, type: TASKSTATS_TYPE_TGID, pid: tgid); |
545 | if (!stats) |
546 | goto err; |
547 | |
548 | rc = fill_stats_for_tgid(tgid, stats); |
549 | if (rc < 0) |
550 | goto err; |
551 | return send_reply(skb: rep_skb, info); |
552 | err: |
553 | nlmsg_free(skb: rep_skb); |
554 | return rc; |
555 | } |
556 | |
557 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
558 | { |
559 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) |
560 | return cmd_attr_register_cpumask(info); |
561 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) |
562 | return cmd_attr_deregister_cpumask(info); |
563 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) |
564 | return cmd_attr_pid(info); |
565 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) |
566 | return cmd_attr_tgid(info); |
567 | else |
568 | return -EINVAL; |
569 | } |
570 | |
571 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
572 | { |
573 | struct signal_struct *sig = tsk->signal; |
574 | struct taskstats *stats_new, *stats; |
575 | |
576 | /* Pairs with smp_store_release() below. */ |
577 | stats = smp_load_acquire(&sig->stats); |
578 | if (stats || thread_group_empty(p: tsk)) |
579 | return stats; |
580 | |
581 | /* No problem if kmem_cache_zalloc() fails */ |
582 | stats_new = kmem_cache_zalloc(k: taskstats_cache, GFP_KERNEL); |
583 | |
584 | spin_lock_irq(lock: &tsk->sighand->siglock); |
585 | stats = sig->stats; |
586 | if (!stats) { |
587 | /* |
588 | * Pairs with smp_store_release() above and order the |
589 | * kmem_cache_zalloc(). |
590 | */ |
591 | smp_store_release(&sig->stats, stats_new); |
592 | stats = stats_new; |
593 | stats_new = NULL; |
594 | } |
595 | spin_unlock_irq(lock: &tsk->sighand->siglock); |
596 | |
597 | if (stats_new) |
598 | kmem_cache_free(s: taskstats_cache, objp: stats_new); |
599 | |
600 | return stats; |
601 | } |
602 | |
603 | /* Send pid data out on exit */ |
604 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
605 | { |
606 | int rc; |
607 | struct listener_list *listeners; |
608 | struct taskstats *stats; |
609 | struct sk_buff *rep_skb; |
610 | size_t size; |
611 | int is_thread_group; |
612 | |
613 | if (!family_registered) |
614 | return; |
615 | |
616 | /* |
617 | * Size includes space for nested attributes |
618 | */ |
619 | size = taskstats_packet_size(); |
620 | |
621 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
622 | if (is_thread_group) { |
623 | /* PID + STATS + TGID + STATS */ |
624 | size = 2 * size; |
625 | /* fill the tsk->signal->stats structure */ |
626 | fill_tgid_exit(tsk); |
627 | } |
628 | |
629 | listeners = raw_cpu_ptr(&listener_array); |
630 | if (list_empty(head: &listeners->list)) |
631 | return; |
632 | |
633 | rc = prepare_reply(NULL, cmd: TASKSTATS_CMD_NEW, skbp: &rep_skb, size); |
634 | if (rc < 0) |
635 | return; |
636 | |
637 | stats = mk_reply(skb: rep_skb, type: TASKSTATS_TYPE_PID, |
638 | pid: task_pid_nr_ns(tsk, ns: &init_pid_ns)); |
639 | if (!stats) |
640 | goto err; |
641 | |
642 | fill_stats(user_ns: &init_user_ns, pid_ns: &init_pid_ns, tsk, stats); |
643 | if (group_dead) |
644 | stats->ac_flag |= AGROUP; |
645 | |
646 | /* |
647 | * Doesn't matter if tsk is the leader or the last group member leaving |
648 | */ |
649 | if (!is_thread_group || !group_dead) |
650 | goto send; |
651 | |
652 | stats = mk_reply(skb: rep_skb, type: TASKSTATS_TYPE_TGID, |
653 | pid: task_tgid_nr_ns(tsk, ns: &init_pid_ns)); |
654 | if (!stats) |
655 | goto err; |
656 | |
657 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); |
658 | |
659 | send: |
660 | send_cpu_listeners(skb: rep_skb, listeners); |
661 | return; |
662 | err: |
663 | nlmsg_free(skb: rep_skb); |
664 | } |
665 | |
666 | static const struct genl_ops taskstats_ops[] = { |
667 | { |
668 | .cmd = TASKSTATS_CMD_GET, |
669 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
670 | .doit = taskstats_user_cmd, |
671 | .policy = taskstats_cmd_get_policy, |
672 | .maxattr = ARRAY_SIZE(taskstats_cmd_get_policy) - 1, |
673 | .flags = GENL_ADMIN_PERM, |
674 | }, |
675 | { |
676 | .cmd = CGROUPSTATS_CMD_GET, |
677 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
678 | .doit = cgroupstats_user_cmd, |
679 | .policy = cgroupstats_cmd_get_policy, |
680 | .maxattr = ARRAY_SIZE(cgroupstats_cmd_get_policy) - 1, |
681 | }, |
682 | }; |
683 | |
684 | static struct genl_family family __ro_after_init = { |
685 | .name = TASKSTATS_GENL_NAME, |
686 | .version = TASKSTATS_GENL_VERSION, |
687 | .module = THIS_MODULE, |
688 | .ops = taskstats_ops, |
689 | .n_ops = ARRAY_SIZE(taskstats_ops), |
690 | .resv_start_op = CGROUPSTATS_CMD_GET + 1, |
691 | .netnsok = true, |
692 | }; |
693 | |
694 | /* Needed early in initialization */ |
695 | void __init taskstats_init_early(void) |
696 | { |
697 | unsigned int i; |
698 | |
699 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
700 | for_each_possible_cpu(i) { |
701 | INIT_LIST_HEAD(list: &(per_cpu(listener_array, i).list)); |
702 | init_rwsem(&(per_cpu(listener_array, i).sem)); |
703 | } |
704 | } |
705 | |
706 | static int __init taskstats_init(void) |
707 | { |
708 | int rc; |
709 | |
710 | rc = genl_register_family(family: &family); |
711 | if (rc) |
712 | return rc; |
713 | |
714 | family_registered = 1; |
715 | pr_info("registered taskstats version %d\n" , TASKSTATS_GENL_VERSION); |
716 | return 0; |
717 | } |
718 | |
719 | /* |
720 | * late initcall ensures initialization of statistics collection |
721 | * mechanisms precedes initialization of the taskstats interface |
722 | */ |
723 | late_initcall(taskstats_init); |
724 | |