~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/kernel/taskstats.c

Version: ~ [ linux-5.4-rc7 ] ~ [ linux-5.3.11 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.84 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.154 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.201 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.201 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.77 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 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         if (!skb)
 90                 return -ENOMEM;
 91 
 92         if (!info) {
 93                 int seq = this_cpu_inc_return(taskstats_seqnum) - 1;
 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 
115         genlmsg_end(skb, reply);
116 
117         return genlmsg_reply(skb, info);
118 }
119 
120 /*
121  * Send taskstats data in @skb to listeners registered for @cpu's exit data
122  */
123 static void send_cpu_listeners(struct sk_buff *skb,
124                                         struct listener_list *listeners)
125 {
126         struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
127         struct listener *s, *tmp;
128         struct sk_buff *skb_next, *skb_cur = skb;
129         void *reply = genlmsg_data(genlhdr);
130         int rc, delcount = 0;
131 
132         genlmsg_end(skb, reply);
133 
134         rc = 0;
135         down_read(&listeners->sem);
136         list_for_each_entry(s, &listeners->list, list) {
137                 skb_next = NULL;
138                 if (!list_is_last(&s->list, &listeners->list)) {
139                         skb_next = skb_clone(skb_cur, GFP_KERNEL);
140                         if (!skb_next)
141                                 break;
142                 }
143                 rc = genlmsg_unicast(&init_net, skb_cur, s->pid);
144                 if (rc == -ECONNREFUSED) {
145                         s->valid = 0;
146                         delcount++;
147                 }
148                 skb_cur = skb_next;
149         }
150         up_read(&listeners->sem);
151 
152         if (skb_cur)
153                 nlmsg_free(skb_cur);
154 
155         if (!delcount)
156                 return;
157 
158         /* Delete invalidated entries */
159         down_write(&listeners->sem);
160         list_for_each_entry_safe(s, tmp, &listeners->list, list) {
161                 if (!s->valid) {
162                         list_del(&s->list);
163                         kfree(s);
164                 }
165         }
166         up_write(&listeners->sem);
167 }
168 
169 static void fill_stats(struct user_namespace *user_ns,
170                        struct pid_namespace *pid_ns,
171                        struct task_struct *tsk, struct taskstats *stats)
172 {
173         memset(stats, 0, sizeof(*stats));
174         /*
175          * Each accounting subsystem adds calls to its functions to
176          * fill in relevant parts of struct taskstsats as follows
177          *
178          *      per-task-foo(stats, tsk);
179          */
180 
181         delayacct_add_tsk(stats, tsk);
182 
183         /* fill in basic acct fields */
184         stats->version = TASKSTATS_VERSION;
185         stats->nvcsw = tsk->nvcsw;
186         stats->nivcsw = tsk->nivcsw;
187         bacct_add_tsk(user_ns, pid_ns, stats, tsk);
188 
189         /* fill in extended acct fields */
190         xacct_add_tsk(stats, tsk);
191 }
192 
193 static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
194 {
195         struct task_struct *tsk;
196 
197         rcu_read_lock();
198         tsk = find_task_by_vpid(pid);
199         if (tsk)
200                 get_task_struct(tsk);
201         rcu_read_unlock();
202         if (!tsk)
203                 return -ESRCH;
204         fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats);
205         put_task_struct(tsk);
206         return 0;
207 }
208 
209 static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
210 {
211         struct task_struct *tsk, *first;
212         unsigned long flags;
213         int rc = -ESRCH;
214 
215         /*
216          * Add additional stats from live tasks except zombie thread group
217          * leaders who are already counted with the dead tasks
218          */
219         rcu_read_lock();
220         first = find_task_by_vpid(tgid);
221 
222         if (!first || !lock_task_sighand(first, &flags))
223                 goto out;
224 
225         if (first->signal->stats)
226                 memcpy(stats, first->signal->stats, sizeof(*stats));
227         else
228                 memset(stats, 0, sizeof(*stats));
229 
230         tsk = first;
231         do {
232                 if (tsk->exit_state)
233                         continue;
234                 /*
235                  * Accounting subsystem can call its functions here to
236                  * fill in relevant parts of struct taskstsats as follows
237                  *
238                  *      per-task-foo(stats, tsk);
239                  */
240                 delayacct_add_tsk(stats, tsk);
241 
242                 stats->nvcsw += tsk->nvcsw;
243                 stats->nivcsw += tsk->nivcsw;
244         } while_each_thread(first, tsk);
245 
246         unlock_task_sighand(first, &flags);
247         rc = 0;
248 out:
249         rcu_read_unlock();
250 
251         stats->version = TASKSTATS_VERSION;
252         /*
253          * Accounting subsystems can also add calls here to modify
254          * fields of taskstats.
255          */
256         return rc;
257 }
258 
259 static void fill_tgid_exit(struct task_struct *tsk)
260 {
261         unsigned long flags;
262 
263         spin_lock_irqsave(&tsk->sighand->siglock, flags);
264         if (!tsk->signal->stats)
265                 goto ret;
266 
267         /*
268          * Each accounting subsystem calls its functions here to
269          * accumalate its per-task stats for tsk, into the per-tgid structure
270          *
271          *      per-task-foo(tsk->signal->stats, tsk);
272          */
273         delayacct_add_tsk(tsk->signal->stats, tsk);
274 ret:
275         spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
276         return;
277 }
278 
279 static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd)
280 {
281         struct listener_list *listeners;
282         struct listener *s, *tmp, *s2;
283         unsigned int cpu;
284         int ret = 0;
285 
286         if (!cpumask_subset(mask, cpu_possible_mask))
287                 return -EINVAL;
288 
289         if (current_user_ns() != &init_user_ns)
290                 return -EINVAL;
291 
292         if (task_active_pid_ns(current) != &init_pid_ns)
293                 return -EINVAL;
294 
295         if (isadd == REGISTER) {
296                 for_each_cpu(cpu, mask) {
297                         s = kmalloc_node(sizeof(struct listener),
298                                         GFP_KERNEL, cpu_to_node(cpu));
299                         if (!s) {
300                                 ret = -ENOMEM;
301                                 goto cleanup;
302                         }
303                         s->pid = pid;
304                         s->valid = 1;
305 
306                         listeners = &per_cpu(listener_array, cpu);
307                         down_write(&listeners->sem);
308                         list_for_each_entry(s2, &listeners->list, list) {
309                                 if (s2->pid == pid && s2->valid)
310                                         goto exists;
311                         }
312                         list_add(&s->list, &listeners->list);
313                         s = NULL;
314 exists:
315                         up_write(&listeners->sem);
316                         kfree(s); /* nop if NULL */
317                 }
318                 return 0;
319         }
320 
321         /* Deregister or cleanup */
322 cleanup:
323         for_each_cpu(cpu, mask) {
324                 listeners = &per_cpu(listener_array, cpu);
325                 down_write(&listeners->sem);
326                 list_for_each_entry_safe(s, tmp, &listeners->list, list) {
327                         if (s->pid == pid) {
328                                 list_del(&s->list);
329                                 kfree(s);
330                                 break;
331                         }
332                 }
333                 up_write(&listeners->sem);
334         }
335         return ret;
336 }
337 
338 static int parse(struct nlattr *na, struct cpumask *mask)
339 {
340         char *data;
341         int len;
342         int ret;
343 
344         if (na == NULL)
345                 return 1;
346         len = nla_len(na);
347         if (len > TASKSTATS_CPUMASK_MAXLEN)
348                 return -E2BIG;
349         if (len < 1)
350                 return -EINVAL;
351         data = kmalloc(len, GFP_KERNEL);
352         if (!data)
353                 return -ENOMEM;
354         nla_strlcpy(data, na, len);
355         ret = cpulist_parse(data, mask);
356         kfree(data);
357         return ret;
358 }
359 
360 #if defined(CONFIG_64BIT) && !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
361 #define TASKSTATS_NEEDS_PADDING 1
362 #endif
363 
364 static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
365 {
366         struct nlattr *na, *ret;
367         int aggr;
368 
369         aggr = (type == TASKSTATS_TYPE_PID)
370                         ? TASKSTATS_TYPE_AGGR_PID
371                         : TASKSTATS_TYPE_AGGR_TGID;
372 
373         /*
374          * The taskstats structure is internally aligned on 8 byte
375          * boundaries but the layout of the aggregrate reply, with
376          * two NLA headers and the pid (each 4 bytes), actually
377          * force the entire structure to be unaligned. This causes
378          * the kernel to issue unaligned access warnings on some
379          * architectures like ia64. Unfortunately, some software out there
380          * doesn't properly unroll the NLA packet and assumes that the start
381          * of the taskstats structure will always be 20 bytes from the start
382          * of the netlink payload. Aligning the start of the taskstats
383          * structure breaks this software, which we don't want. So, for now
384          * the alignment only happens on architectures that require it
385          * and those users will have to update to fixed versions of those
386          * packages. Space is reserved in the packet only when needed.
387          * This ifdef should be removed in several years e.g. 2012 once
388          * we can be confident that fixed versions are installed on most
389          * systems. We add the padding before the aggregate since the
390          * aggregate is already a defined type.
391          */
392 #ifdef TASKSTATS_NEEDS_PADDING
393         if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0)
394                 goto err;
395 #endif
396         na = nla_nest_start(skb, aggr);
397         if (!na)
398                 goto err;
399 
400         if (nla_put(skb, type, sizeof(pid), &pid) < 0) {
401                 nla_nest_cancel(skb, na);
402                 goto err;
403         }
404         ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
405         if (!ret) {
406                 nla_nest_cancel(skb, na);
407                 goto err;
408         }
409         nla_nest_end(skb, na);
410 
411         return nla_data(ret);
412 err:
413         return NULL;
414 }
415 
416 static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
417 {
418         int rc = 0;
419         struct sk_buff *rep_skb;
420         struct cgroupstats *stats;
421         struct nlattr *na;
422         size_t size;
423         u32 fd;
424         struct fd f;
425 
426         na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
427         if (!na)
428                 return -EINVAL;
429 
430         fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
431         f = fdget(fd);
432         if (!f.file)
433                 return 0;
434 
435         size = nla_total_size(sizeof(struct cgroupstats));
436 
437         rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb,
438                                 size);
439         if (rc < 0)
440                 goto err;
441 
442         na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS,
443                                 sizeof(struct cgroupstats));
444         if (na == NULL) {
445                 nlmsg_free(rep_skb);
446                 rc = -EMSGSIZE;
447                 goto err;
448         }
449 
450         stats = nla_data(na);
451         memset(stats, 0, sizeof(*stats));
452 
453         rc = cgroupstats_build(stats, f.file->f_path.dentry);
454         if (rc < 0) {
455                 nlmsg_free(rep_skb);
456                 goto err;
457         }
458 
459         rc = send_reply(rep_skb, info);
460 
461 err:
462         fdput(f);
463         return rc;
464 }
465 
466 static int cmd_attr_register_cpumask(struct genl_info *info)
467 {
468         cpumask_var_t mask;
469         int rc;
470 
471         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
472                 return -ENOMEM;
473         rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask);
474         if (rc < 0)
475                 goto out;
476         rc = add_del_listener(info->snd_portid, mask, REGISTER);
477 out:
478         free_cpumask_var(mask);
479         return rc;
480 }
481 
482 static int cmd_attr_deregister_cpumask(struct genl_info *info)
483 {
484         cpumask_var_t mask;
485         int rc;
486 
487         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
488                 return -ENOMEM;
489         rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask);
490         if (rc < 0)
491                 goto out;
492         rc = add_del_listener(info->snd_portid, mask, DEREGISTER);
493 out:
494         free_cpumask_var(mask);
495         return rc;
496 }
497 
498 static size_t taskstats_packet_size(void)
499 {
500         size_t size;
501 
502         size = nla_total_size(sizeof(u32)) +
503                 nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
504 #ifdef TASKSTATS_NEEDS_PADDING
505         size += nla_total_size(0); /* Padding for alignment */
506 #endif
507         return size;
508 }
509 
510 static int cmd_attr_pid(struct genl_info *info)
511 {
512         struct taskstats *stats;
513         struct sk_buff *rep_skb;
514         size_t size;
515         u32 pid;
516         int rc;
517 
518         size = taskstats_packet_size();
519 
520         rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
521         if (rc < 0)
522                 return rc;
523 
524         rc = -EINVAL;
525         pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
526         stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
527         if (!stats)
528                 goto err;
529 
530         rc = fill_stats_for_pid(pid, stats);
531         if (rc < 0)
532                 goto err;
533         return send_reply(rep_skb, info);
534 err:
535         nlmsg_free(rep_skb);
536         return rc;
537 }
538 
539 static int cmd_attr_tgid(struct genl_info *info)
540 {
541         struct taskstats *stats;
542         struct sk_buff *rep_skb;
543         size_t size;
544         u32 tgid;
545         int rc;
546 
547         size = taskstats_packet_size();
548 
549         rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
550         if (rc < 0)
551                 return rc;
552 
553         rc = -EINVAL;
554         tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
555         stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
556         if (!stats)
557                 goto err;
558 
559         rc = fill_stats_for_tgid(tgid, stats);
560         if (rc < 0)
561                 goto err;
562         return send_reply(rep_skb, info);
563 err:
564         nlmsg_free(rep_skb);
565         return rc;
566 }
567 
568 static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
569 {
570         if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK])
571                 return cmd_attr_register_cpumask(info);
572         else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK])
573                 return cmd_attr_deregister_cpumask(info);
574         else if (info->attrs[TASKSTATS_CMD_ATTR_PID])
575                 return cmd_attr_pid(info);
576         else if (info->attrs[TASKSTATS_CMD_ATTR_TGID])
577                 return cmd_attr_tgid(info);
578         else
579                 return -EINVAL;
580 }
581 
582 static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
583 {
584         struct signal_struct *sig = tsk->signal;
585         struct taskstats *stats;
586 
587         if (sig->stats || thread_group_empty(tsk))
588                 goto ret;
589 
590         /* No problem if kmem_cache_zalloc() fails */
591         stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
592 
593         spin_lock_irq(&tsk->sighand->siglock);
594         if (!sig->stats) {
595                 sig->stats = stats;
596                 stats = NULL;
597         }
598         spin_unlock_irq(&tsk->sighand->siglock);
599 
600         if (stats)
601                 kmem_cache_free(taskstats_cache, stats);
602 ret:
603         return sig->stats;
604 }
605 
606 /* Send pid data out on exit */
607 void taskstats_exit(struct task_struct *tsk, int group_dead)
608 {
609         int rc;
610         struct listener_list *listeners;
611         struct taskstats *stats;
612         struct sk_buff *rep_skb;
613         size_t size;
614         int is_thread_group;
615 
616         if (!family_registered)
617                 return;
618 
619         /*
620          * Size includes space for nested attributes
621          */
622         size = taskstats_packet_size();
623 
624         is_thread_group = !!taskstats_tgid_alloc(tsk);
625         if (is_thread_group) {
626                 /* PID + STATS + TGID + STATS */
627                 size = 2 * size;
628                 /* fill the tsk->signal->stats structure */
629                 fill_tgid_exit(tsk);
630         }
631 
632         listeners = raw_cpu_ptr(&listener_array);
633         if (list_empty(&listeners->list))
634                 return;
635 
636         rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
637         if (rc < 0)
638                 return;
639 
640         stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID,
641                          task_pid_nr_ns(tsk, &init_pid_ns));
642         if (!stats)
643                 goto err;
644 
645         fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
646 
647         /*
648          * Doesn't matter if tsk is the leader or the last group member leaving
649          */
650         if (!is_thread_group || !group_dead)
651                 goto send;
652 
653         stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID,
654                          task_tgid_nr_ns(tsk, &init_pid_ns));
655         if (!stats)
656                 goto err;
657 
658         memcpy(stats, tsk->signal->stats, sizeof(*stats));
659 
660 send:
661         send_cpu_listeners(rep_skb, listeners);
662         return;
663 err:
664         nlmsg_free(rep_skb);
665 }
666 
667 static const struct genl_ops taskstats_ops[] = {
668         {
669                 .cmd            = TASKSTATS_CMD_GET,
670                 .doit           = taskstats_user_cmd,
671                 .policy         = taskstats_cmd_get_policy,
672                 .flags          = GENL_ADMIN_PERM,
673         },
674         {
675                 .cmd            = CGROUPSTATS_CMD_GET,
676                 .doit           = cgroupstats_user_cmd,
677                 .policy         = cgroupstats_cmd_get_policy,
678         },
679 };
680 
681 /* Needed early in initialization */
682 void __init taskstats_init_early(void)
683 {
684         unsigned int i;
685 
686         taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC);
687         for_each_possible_cpu(i) {
688                 INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
689                 init_rwsem(&(per_cpu(listener_array, i).sem));
690         }
691 }
692 
693 static int __init taskstats_init(void)
694 {
695         int rc;
696 
697         rc = genl_register_family_with_ops(&family, taskstats_ops);
698         if (rc)
699                 return rc;
700 
701         family_registered = 1;
702         pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION);
703         return 0;
704 }
705 
706 /*
707  * late initcall ensures initialization of statistics collection
708  * mechanisms precedes initialization of the taskstats interface
709  */
710 late_initcall(taskstats_init);
711 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp