Commit | Line | Data |
---|---|---|
c757249a SN |
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> | |
f3cef7a9 | 21 | #include <linux/tsacct_kern.h> |
6f44993f | 22 | #include <linux/delayacct.h> |
f9fd8914 SN |
23 | #include <linux/cpumask.h> |
24 | #include <linux/percpu.h> | |
5a0e3ad6 | 25 | #include <linux/slab.h> |
846c7bb0 BS |
26 | #include <linux/cgroupstats.h> |
27 | #include <linux/cgroup.h> | |
28 | #include <linux/fs.h> | |
29 | #include <linux/file.h> | |
c757249a SN |
30 | #include <net/genetlink.h> |
31 | #include <asm/atomic.h> | |
32 | ||
f9fd8914 SN |
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 | ||
b81f3ea9 | 39 | static DEFINE_PER_CPU(__u32, taskstats_seqnum); |
c757249a | 40 | static int family_registered; |
e18b890b | 41 | struct kmem_cache *taskstats_cache; |
c757249a SN |
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 | ||
b54452b0 | 50 | static const struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = { |
c757249a SN |
51 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
52 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, | |
f9fd8914 SN |
53 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
54 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; | |
55 | ||
b54452b0 | 56 | static const struct nla_policy cgroupstats_cmd_get_policy[CGROUPSTATS_CMD_ATTR_MAX+1] = { |
846c7bb0 BS |
57 | [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 }, |
58 | }; | |
59 | ||
f9fd8914 SN |
60 | struct listener { |
61 | struct list_head list; | |
62 | pid_t pid; | |
bb129994 | 63 | char valid; |
c757249a SN |
64 | }; |
65 | ||
f9fd8914 SN |
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 | }; | |
c757249a SN |
77 | |
78 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, | |
37167485 | 79 | size_t size) |
c757249a SN |
80 | { |
81 | struct sk_buff *skb; | |
82 | void *reply; | |
83 | ||
84 | /* | |
85 | * If new attributes are added, please revisit this allocation | |
86 | */ | |
3dabc715 | 87 | skb = genlmsg_new(size, GFP_KERNEL); |
c757249a SN |
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 | ||
17c157c8 | 95 | reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); |
c757249a | 96 | } else |
17c157c8 | 97 | reply = genlmsg_put_reply(skb, info, &family, 0, cmd); |
c757249a SN |
98 | if (reply == NULL) { |
99 | nlmsg_free(skb); | |
100 | return -EINVAL; | |
101 | } | |
102 | ||
103 | *skbp = skb; | |
c757249a SN |
104 | return 0; |
105 | } | |
106 | ||
f9fd8914 SN |
107 | /* |
108 | * Send taskstats data in @skb to listener with nl_pid @pid | |
109 | */ | |
134e6375 | 110 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
c757249a | 111 | { |
b529ccf2 | 112 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 | 113 | void *reply = genlmsg_data(genlhdr); |
c757249a SN |
114 | int rc; |
115 | ||
c757249a SN |
116 | rc = genlmsg_end(skb, reply); |
117 | if (rc < 0) { | |
118 | nlmsg_free(skb); | |
119 | return rc; | |
120 | } | |
121 | ||
134e6375 | 122 | return genlmsg_reply(skb, info); |
c757249a SN |
123 | } |
124 | ||
f9fd8914 SN |
125 | /* |
126 | * Send taskstats data in @skb to listeners registered for @cpu's exit data | |
127 | */ | |
115085ea ON |
128 | static void send_cpu_listeners(struct sk_buff *skb, |
129 | struct listener_list *listeners) | |
f9fd8914 | 130 | { |
b529ccf2 | 131 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 SN |
132 | struct listener *s, *tmp; |
133 | struct sk_buff *skb_next, *skb_cur = skb; | |
134 | void *reply = genlmsg_data(genlhdr); | |
d94a0415 | 135 | int rc, delcount = 0; |
f9fd8914 SN |
136 | |
137 | rc = genlmsg_end(skb, reply); | |
138 | if (rc < 0) { | |
139 | nlmsg_free(skb); | |
d94a0415 | 140 | return; |
f9fd8914 SN |
141 | } |
142 | ||
143 | rc = 0; | |
bb129994 | 144 | down_read(&listeners->sem); |
d94a0415 | 145 | list_for_each_entry(s, &listeners->list, list) { |
f9fd8914 SN |
146 | skb_next = NULL; |
147 | if (!list_is_last(&s->list, &listeners->list)) { | |
148 | skb_next = skb_clone(skb_cur, GFP_KERNEL); | |
d94a0415 | 149 | if (!skb_next) |
f9fd8914 | 150 | break; |
f9fd8914 | 151 | } |
134e6375 | 152 | rc = genlmsg_unicast(&init_net, skb_cur, s->pid); |
d94a0415 | 153 | if (rc == -ECONNREFUSED) { |
bb129994 SN |
154 | s->valid = 0; |
155 | delcount++; | |
f9fd8914 SN |
156 | } |
157 | skb_cur = skb_next; | |
158 | } | |
bb129994 | 159 | up_read(&listeners->sem); |
f9fd8914 | 160 | |
d94a0415 SN |
161 | if (skb_cur) |
162 | nlmsg_free(skb_cur); | |
163 | ||
bb129994 | 164 | if (!delcount) |
d94a0415 | 165 | return; |
bb129994 SN |
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); | |
f9fd8914 SN |
176 | } |
177 | ||
3d9e0cf1 | 178 | static void fill_stats(struct task_struct *tsk, struct taskstats *stats) |
c757249a | 179 | { |
51de4d90 | 180 | memset(stats, 0, sizeof(*stats)); |
c757249a SN |
181 | /* |
182 | * Each accounting subsystem adds calls to its functions to | |
183 | * fill in relevant parts of struct taskstsats as follows | |
184 | * | |
7d94dddd | 185 | * per-task-foo(stats, tsk); |
c757249a SN |
186 | */ |
187 | ||
7d94dddd | 188 | delayacct_add_tsk(stats, tsk); |
f3cef7a9 JL |
189 | |
190 | /* fill in basic acct fields */ | |
6f44993f | 191 | stats->version = TASKSTATS_VERSION; |
b663a79c MU |
192 | stats->nvcsw = tsk->nvcsw; |
193 | stats->nivcsw = tsk->nivcsw; | |
f3cef7a9 | 194 | bacct_add_tsk(stats, tsk); |
6f44993f | 195 | |
9acc1853 JL |
196 | /* fill in extended acct fields */ |
197 | xacct_add_tsk(stats, tsk); | |
3d9e0cf1 | 198 | } |
9acc1853 | 199 | |
3d9e0cf1 MH |
200 | static int fill_stats_for_pid(pid_t pid, struct taskstats *stats) |
201 | { | |
202 | struct task_struct *tsk; | |
c757249a | 203 | |
3d9e0cf1 MH |
204 | rcu_read_lock(); |
205 | tsk = find_task_by_vpid(pid); | |
206 | if (tsk) | |
207 | get_task_struct(tsk); | |
208 | rcu_read_unlock(); | |
209 | if (!tsk) | |
210 | return -ESRCH; | |
211 | fill_stats(tsk, stats); | |
212 | put_task_struct(tsk); | |
213 | return 0; | |
c757249a SN |
214 | } |
215 | ||
3d9e0cf1 | 216 | static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) |
c757249a | 217 | { |
3d9e0cf1 | 218 | struct task_struct *tsk, *first; |
ad4ecbcb | 219 | unsigned long flags; |
a98b6094 | 220 | int rc = -ESRCH; |
c757249a | 221 | |
ad4ecbcb SN |
222 | /* |
223 | * Add additional stats from live tasks except zombie thread group | |
224 | * leaders who are already counted with the dead tasks | |
225 | */ | |
a98b6094 | 226 | rcu_read_lock(); |
3d9e0cf1 | 227 | first = find_task_by_vpid(tgid); |
ad4ecbcb | 228 | |
a98b6094 ON |
229 | if (!first || !lock_task_sighand(first, &flags)) |
230 | goto out; | |
ad4ecbcb | 231 | |
a98b6094 ON |
232 | if (first->signal->stats) |
233 | memcpy(stats, first->signal->stats, sizeof(*stats)); | |
51de4d90 ON |
234 | else |
235 | memset(stats, 0, sizeof(*stats)); | |
fca178c0 | 236 | |
a98b6094 | 237 | tsk = first; |
c757249a | 238 | do { |
d7c3f5f2 | 239 | if (tsk->exit_state) |
ad4ecbcb | 240 | continue; |
c757249a | 241 | /* |
ad4ecbcb | 242 | * Accounting subsystem can call its functions here to |
c757249a SN |
243 | * fill in relevant parts of struct taskstsats as follows |
244 | * | |
ad4ecbcb | 245 | * per-task-foo(stats, tsk); |
c757249a | 246 | */ |
ad4ecbcb | 247 | delayacct_add_tsk(stats, tsk); |
6f44993f | 248 | |
b663a79c MU |
249 | stats->nvcsw += tsk->nvcsw; |
250 | stats->nivcsw += tsk->nivcsw; | |
c757249a | 251 | } while_each_thread(first, tsk); |
6f44993f | 252 | |
a98b6094 ON |
253 | unlock_task_sighand(first, &flags); |
254 | rc = 0; | |
255 | out: | |
256 | rcu_read_unlock(); | |
257 | ||
258 | stats->version = TASKSTATS_VERSION; | |
c757249a | 259 | /* |
3a4fa0a2 | 260 | * Accounting subsystems can also add calls here to modify |
ad4ecbcb | 261 | * fields of taskstats. |
c757249a | 262 | */ |
a98b6094 | 263 | return rc; |
ad4ecbcb SN |
264 | } |
265 | ||
ad4ecbcb SN |
266 | static void fill_tgid_exit(struct task_struct *tsk) |
267 | { | |
268 | unsigned long flags; | |
269 | ||
b8534d7b | 270 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
ad4ecbcb SN |
271 | if (!tsk->signal->stats) |
272 | goto ret; | |
273 | ||
274 | /* | |
275 | * Each accounting subsystem calls its functions here to | |
276 | * accumalate its per-task stats for tsk, into the per-tgid structure | |
277 | * | |
278 | * per-task-foo(tsk->signal->stats, tsk); | |
279 | */ | |
280 | delayacct_add_tsk(tsk->signal->stats, tsk); | |
281 | ret: | |
b8534d7b | 282 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
ad4ecbcb | 283 | return; |
c757249a SN |
284 | } |
285 | ||
41c7bb95 | 286 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
f9fd8914 SN |
287 | { |
288 | struct listener_list *listeners; | |
289 | struct listener *s, *tmp; | |
290 | unsigned int cpu; | |
ad4ecbcb | 291 | |
41c7bb95 | 292 | if (!cpumask_subset(mask, cpu_possible_mask)) |
f9fd8914 SN |
293 | return -EINVAL; |
294 | ||
295 | if (isadd == REGISTER) { | |
41c7bb95 | 296 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
297 | s = kmalloc_node(sizeof(struct listener), GFP_KERNEL, |
298 | cpu_to_node(cpu)); | |
299 | if (!s) | |
300 | goto cleanup; | |
301 | s->pid = pid; | |
302 | INIT_LIST_HEAD(&s->list); | |
bb129994 | 303 | s->valid = 1; |
f9fd8914 SN |
304 | |
305 | listeners = &per_cpu(listener_array, cpu); | |
306 | down_write(&listeners->sem); | |
307 | list_add(&s->list, &listeners->list); | |
308 | up_write(&listeners->sem); | |
309 | } | |
310 | return 0; | |
311 | } | |
312 | ||
313 | /* Deregister or cleanup */ | |
314 | cleanup: | |
41c7bb95 | 315 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
316 | listeners = &per_cpu(listener_array, cpu); |
317 | down_write(&listeners->sem); | |
318 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
319 | if (s->pid == pid) { | |
320 | list_del(&s->list); | |
321 | kfree(s); | |
322 | break; | |
323 | } | |
324 | } | |
325 | up_write(&listeners->sem); | |
326 | } | |
327 | return 0; | |
328 | } | |
329 | ||
41c7bb95 | 330 | static int parse(struct nlattr *na, struct cpumask *mask) |
f9fd8914 SN |
331 | { |
332 | char *data; | |
333 | int len; | |
334 | int ret; | |
335 | ||
336 | if (na == NULL) | |
337 | return 1; | |
338 | len = nla_len(na); | |
339 | if (len > TASKSTATS_CPUMASK_MAXLEN) | |
340 | return -E2BIG; | |
341 | if (len < 1) | |
342 | return -EINVAL; | |
343 | data = kmalloc(len, GFP_KERNEL); | |
344 | if (!data) | |
345 | return -ENOMEM; | |
346 | nla_strlcpy(data, na, len); | |
29c0177e | 347 | ret = cpulist_parse(data, mask); |
f9fd8914 SN |
348 | kfree(data); |
349 | return ret; | |
350 | } | |
351 | ||
51de4d90 | 352 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
68062b86 | 353 | { |
51de4d90 | 354 | struct nlattr *na, *ret; |
68062b86 ON |
355 | int aggr; |
356 | ||
85893120 JM |
357 | /* If we don't pad, we end up with alignment on a 4 byte boundary. |
358 | * This causes lots of runtime warnings on systems requiring 8 byte | |
359 | * alignment */ | |
360 | u32 pids[2] = { pid, 0 }; | |
361 | int pid_size = ALIGN(sizeof(pid), sizeof(long)); | |
362 | ||
37167485 ON |
363 | aggr = (type == TASKSTATS_TYPE_PID) |
364 | ? TASKSTATS_TYPE_AGGR_PID | |
365 | : TASKSTATS_TYPE_AGGR_TGID; | |
68062b86 ON |
366 | |
367 | na = nla_nest_start(skb, aggr); | |
37167485 ON |
368 | if (!na) |
369 | goto err; | |
85893120 | 370 | if (nla_put(skb, type, pid_size, pids) < 0) |
51de4d90 ON |
371 | goto err; |
372 | ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); | |
373 | if (!ret) | |
374 | goto err; | |
68062b86 ON |
375 | nla_nest_end(skb, na); |
376 | ||
51de4d90 ON |
377 | return nla_data(ret); |
378 | err: | |
379 | return NULL; | |
68062b86 ON |
380 | } |
381 | ||
846c7bb0 BS |
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); | |
f9615984 AB |
399 | if (!file) |
400 | return 0; | |
846c7bb0 | 401 | |
f9615984 | 402 | size = nla_total_size(sizeof(struct cgroupstats)); |
846c7bb0 | 403 | |
f9615984 AB |
404 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
405 | size); | |
406 | if (rc < 0) | |
407 | goto err; | |
846c7bb0 | 408 | |
f9615984 AB |
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)); | |
846c7bb0 | 413 | |
f9615984 AB |
414 | rc = cgroupstats_build(stats, file->f_dentry); |
415 | if (rc < 0) { | |
416 | nlmsg_free(rep_skb); | |
417 | goto err; | |
846c7bb0 BS |
418 | } |
419 | ||
134e6375 | 420 | rc = send_reply(rep_skb, info); |
f9615984 | 421 | |
846c7bb0 | 422 | err: |
f9615984 | 423 | fput_light(file, fput_needed); |
846c7bb0 BS |
424 | return rc; |
425 | } | |
426 | ||
93233125 | 427 | static int cmd_attr_register_cpumask(struct genl_info *info) |
c757249a | 428 | { |
41c7bb95 | 429 | cpumask_var_t mask; |
93233125 | 430 | int rc; |
41c7bb95 RR |
431 | |
432 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) | |
433 | return -ENOMEM; | |
41c7bb95 | 434 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
f9fd8914 | 435 | if (rc < 0) |
93233125 MH |
436 | goto out; |
437 | rc = add_del_listener(info->snd_pid, mask, REGISTER); | |
438 | out: | |
439 | free_cpumask_var(mask); | |
440 | return rc; | |
441 | } | |
442 | ||
443 | static int cmd_attr_deregister_cpumask(struct genl_info *info) | |
444 | { | |
445 | cpumask_var_t mask; | |
446 | int rc; | |
f9fd8914 | 447 | |
93233125 MH |
448 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
449 | return -ENOMEM; | |
41c7bb95 | 450 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
f9fd8914 | 451 | if (rc < 0) |
93233125 MH |
452 | goto out; |
453 | rc = add_del_listener(info->snd_pid, mask, DEREGISTER); | |
454 | out: | |
41c7bb95 | 455 | free_cpumask_var(mask); |
93233125 MH |
456 | return rc; |
457 | } | |
458 | ||
459 | static int cmd_attr_pid(struct genl_info *info) | |
460 | { | |
461 | struct taskstats *stats; | |
462 | struct sk_buff *rep_skb; | |
463 | size_t size; | |
464 | u32 pid; | |
465 | int rc; | |
c757249a | 466 | |
c757249a SN |
467 | size = nla_total_size(sizeof(u32)) + |
468 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); | |
469 | ||
37167485 | 470 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a SN |
471 | if (rc < 0) |
472 | return rc; | |
473 | ||
51de4d90 | 474 | rc = -EINVAL; |
93233125 MH |
475 | pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
476 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); | |
477 | if (!stats) | |
c757249a | 478 | goto err; |
c757249a | 479 | |
3d9e0cf1 | 480 | rc = fill_stats_for_pid(pid, stats); |
93233125 MH |
481 | if (rc < 0) |
482 | goto err; | |
134e6375 | 483 | return send_reply(rep_skb, info); |
c757249a SN |
484 | err: |
485 | nlmsg_free(rep_skb); | |
486 | return rc; | |
487 | } | |
488 | ||
93233125 MH |
489 | static int cmd_attr_tgid(struct genl_info *info) |
490 | { | |
491 | struct taskstats *stats; | |
492 | struct sk_buff *rep_skb; | |
493 | size_t size; | |
494 | u32 tgid; | |
495 | int rc; | |
496 | ||
497 | size = nla_total_size(sizeof(u32)) + | |
498 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); | |
499 | ||
500 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); | |
501 | if (rc < 0) | |
502 | return rc; | |
503 | ||
504 | rc = -EINVAL; | |
505 | tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); | |
506 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); | |
507 | if (!stats) | |
508 | goto err; | |
509 | ||
3d9e0cf1 | 510 | rc = fill_stats_for_tgid(tgid, stats); |
93233125 MH |
511 | if (rc < 0) |
512 | goto err; | |
513 | return send_reply(rep_skb, info); | |
514 | err: | |
515 | nlmsg_free(rep_skb); | |
516 | return rc; | |
517 | } | |
518 | ||
519 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) | |
520 | { | |
521 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) | |
522 | return cmd_attr_register_cpumask(info); | |
523 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) | |
524 | return cmd_attr_deregister_cpumask(info); | |
525 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) | |
526 | return cmd_attr_pid(info); | |
527 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) | |
528 | return cmd_attr_tgid(info); | |
529 | else | |
530 | return -EINVAL; | |
531 | } | |
532 | ||
34ec1234 ON |
533 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
534 | { | |
535 | struct signal_struct *sig = tsk->signal; | |
536 | struct taskstats *stats; | |
537 | ||
538 | if (sig->stats || thread_group_empty(tsk)) | |
539 | goto ret; | |
540 | ||
541 | /* No problem if kmem_cache_zalloc() fails */ | |
542 | stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); | |
543 | ||
544 | spin_lock_irq(&tsk->sighand->siglock); | |
545 | if (!sig->stats) { | |
546 | sig->stats = stats; | |
547 | stats = NULL; | |
548 | } | |
549 | spin_unlock_irq(&tsk->sighand->siglock); | |
550 | ||
551 | if (stats) | |
552 | kmem_cache_free(taskstats_cache, stats); | |
553 | ret: | |
554 | return sig->stats; | |
555 | } | |
556 | ||
c757249a | 557 | /* Send pid data out on exit */ |
115085ea | 558 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
c757249a SN |
559 | { |
560 | int rc; | |
115085ea | 561 | struct listener_list *listeners; |
51de4d90 | 562 | struct taskstats *stats; |
c757249a | 563 | struct sk_buff *rep_skb; |
c757249a SN |
564 | size_t size; |
565 | int is_thread_group; | |
c757249a | 566 | |
4a279ff1 | 567 | if (!family_registered) |
c757249a SN |
568 | return; |
569 | ||
c757249a SN |
570 | /* |
571 | * Size includes space for nested attributes | |
572 | */ | |
573 | size = nla_total_size(sizeof(u32)) + | |
574 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); | |
575 | ||
34ec1234 | 576 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
4a279ff1 ON |
577 | if (is_thread_group) { |
578 | /* PID + STATS + TGID + STATS */ | |
579 | size = 2 * size; | |
580 | /* fill the tsk->signal->stats structure */ | |
581 | fill_tgid_exit(tsk); | |
582 | } | |
583 | ||
115085ea ON |
584 | listeners = &__raw_get_cpu_var(listener_array); |
585 | if (list_empty(&listeners->list)) | |
586 | return; | |
587 | ||
37167485 | 588 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a | 589 | if (rc < 0) |
51de4d90 | 590 | return; |
c757249a | 591 | |
51de4d90 ON |
592 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid); |
593 | if (!stats) | |
37167485 | 594 | goto err; |
c757249a | 595 | |
3d9e0cf1 | 596 | fill_stats(tsk, stats); |
c757249a | 597 | |
c757249a | 598 | /* |
ad4ecbcb | 599 | * Doesn't matter if tsk is the leader or the last group member leaving |
c757249a | 600 | */ |
68062b86 | 601 | if (!is_thread_group || !group_dead) |
ad4ecbcb | 602 | goto send; |
c757249a | 603 | |
51de4d90 ON |
604 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid); |
605 | if (!stats) | |
37167485 | 606 | goto err; |
51de4d90 ON |
607 | |
608 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); | |
c757249a | 609 | |
ad4ecbcb | 610 | send: |
115085ea | 611 | send_cpu_listeners(rep_skb, listeners); |
ad4ecbcb | 612 | return; |
37167485 | 613 | err: |
c757249a | 614 | nlmsg_free(rep_skb); |
c757249a SN |
615 | } |
616 | ||
617 | static struct genl_ops taskstats_ops = { | |
618 | .cmd = TASKSTATS_CMD_GET, | |
f9fd8914 | 619 | .doit = taskstats_user_cmd, |
c757249a SN |
620 | .policy = taskstats_cmd_get_policy, |
621 | }; | |
622 | ||
846c7bb0 BS |
623 | static struct genl_ops cgroupstats_ops = { |
624 | .cmd = CGROUPSTATS_CMD_GET, | |
625 | .doit = cgroupstats_user_cmd, | |
626 | .policy = cgroupstats_cmd_get_policy, | |
627 | }; | |
628 | ||
c757249a SN |
629 | /* Needed early in initialization */ |
630 | void __init taskstats_init_early(void) | |
631 | { | |
f9fd8914 SN |
632 | unsigned int i; |
633 | ||
0a31bd5f | 634 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
f9fd8914 SN |
635 | for_each_possible_cpu(i) { |
636 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); | |
637 | init_rwsem(&(per_cpu(listener_array, i).sem)); | |
638 | } | |
c757249a SN |
639 | } |
640 | ||
641 | static int __init taskstats_init(void) | |
642 | { | |
643 | int rc; | |
644 | ||
645 | rc = genl_register_family(&family); | |
646 | if (rc) | |
647 | return rc; | |
648 | ||
649 | rc = genl_register_ops(&family, &taskstats_ops); | |
650 | if (rc < 0) | |
651 | goto err; | |
652 | ||
846c7bb0 BS |
653 | rc = genl_register_ops(&family, &cgroupstats_ops); |
654 | if (rc < 0) | |
655 | goto err_cgroup_ops; | |
656 | ||
c757249a | 657 | family_registered = 1; |
846c7bb0 | 658 | printk("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
c757249a | 659 | return 0; |
846c7bb0 BS |
660 | err_cgroup_ops: |
661 | genl_unregister_ops(&family, &taskstats_ops); | |
c757249a SN |
662 | err: |
663 | genl_unregister_family(&family); | |
664 | return rc; | |
665 | } | |
666 | ||
667 | /* | |
668 | * late initcall ensures initialization of statistics collection | |
669 | * mechanisms precedes initialization of the taskstats interface | |
670 | */ | |
671 | late_initcall(taskstats_init); |