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Commit | Line | Data |
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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) { | |
cd85fc58 | 92 | int seq = this_cpu_inc_return(taskstats_seqnum) - 1; |
c757249a | 93 | |
17c157c8 | 94 | reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); |
c757249a | 95 | } else |
17c157c8 | 96 | reply = genlmsg_put_reply(skb, info, &family, 0, cmd); |
c757249a SN |
97 | if (reply == NULL) { |
98 | nlmsg_free(skb); | |
99 | return -EINVAL; | |
100 | } | |
101 | ||
102 | *skbp = skb; | |
c757249a SN |
103 | return 0; |
104 | } | |
105 | ||
f9fd8914 SN |
106 | /* |
107 | * Send taskstats data in @skb to listener with nl_pid @pid | |
108 | */ | |
134e6375 | 109 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
c757249a | 110 | { |
b529ccf2 | 111 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 | 112 | void *reply = genlmsg_data(genlhdr); |
c757249a SN |
113 | int rc; |
114 | ||
c757249a SN |
115 | rc = genlmsg_end(skb, reply); |
116 | if (rc < 0) { | |
117 | nlmsg_free(skb); | |
118 | return rc; | |
119 | } | |
120 | ||
134e6375 | 121 | return genlmsg_reply(skb, info); |
c757249a SN |
122 | } |
123 | ||
f9fd8914 SN |
124 | /* |
125 | * Send taskstats data in @skb to listeners registered for @cpu's exit data | |
126 | */ | |
115085ea ON |
127 | static void send_cpu_listeners(struct sk_buff *skb, |
128 | struct listener_list *listeners) | |
f9fd8914 | 129 | { |
b529ccf2 | 130 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 SN |
131 | struct listener *s, *tmp; |
132 | struct sk_buff *skb_next, *skb_cur = skb; | |
133 | void *reply = genlmsg_data(genlhdr); | |
d94a0415 | 134 | int rc, delcount = 0; |
f9fd8914 SN |
135 | |
136 | rc = genlmsg_end(skb, reply); | |
137 | if (rc < 0) { | |
138 | nlmsg_free(skb); | |
d94a0415 | 139 | return; |
f9fd8914 SN |
140 | } |
141 | ||
142 | rc = 0; | |
bb129994 | 143 | down_read(&listeners->sem); |
d94a0415 | 144 | list_for_each_entry(s, &listeners->list, list) { |
f9fd8914 SN |
145 | skb_next = NULL; |
146 | if (!list_is_last(&s->list, &listeners->list)) { | |
147 | skb_next = skb_clone(skb_cur, GFP_KERNEL); | |
d94a0415 | 148 | if (!skb_next) |
f9fd8914 | 149 | break; |
f9fd8914 | 150 | } |
134e6375 | 151 | rc = genlmsg_unicast(&init_net, skb_cur, s->pid); |
d94a0415 | 152 | if (rc == -ECONNREFUSED) { |
bb129994 SN |
153 | s->valid = 0; |
154 | delcount++; | |
f9fd8914 SN |
155 | } |
156 | skb_cur = skb_next; | |
157 | } | |
bb129994 | 158 | up_read(&listeners->sem); |
f9fd8914 | 159 | |
d94a0415 SN |
160 | if (skb_cur) |
161 | nlmsg_free(skb_cur); | |
162 | ||
bb129994 | 163 | if (!delcount) |
d94a0415 | 164 | return; |
bb129994 SN |
165 | |
166 | /* Delete invalidated entries */ | |
167 | down_write(&listeners->sem); | |
168 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
169 | if (!s->valid) { | |
170 | list_del(&s->list); | |
171 | kfree(s); | |
172 | } | |
173 | } | |
174 | up_write(&listeners->sem); | |
f9fd8914 SN |
175 | } |
176 | ||
3d9e0cf1 | 177 | static void fill_stats(struct task_struct *tsk, struct taskstats *stats) |
c757249a | 178 | { |
51de4d90 | 179 | memset(stats, 0, sizeof(*stats)); |
c757249a SN |
180 | /* |
181 | * Each accounting subsystem adds calls to its functions to | |
182 | * fill in relevant parts of struct taskstsats as follows | |
183 | * | |
7d94dddd | 184 | * per-task-foo(stats, tsk); |
c757249a SN |
185 | */ |
186 | ||
7d94dddd | 187 | delayacct_add_tsk(stats, tsk); |
f3cef7a9 JL |
188 | |
189 | /* fill in basic acct fields */ | |
6f44993f | 190 | stats->version = TASKSTATS_VERSION; |
b663a79c MU |
191 | stats->nvcsw = tsk->nvcsw; |
192 | stats->nivcsw = tsk->nivcsw; | |
f3cef7a9 | 193 | bacct_add_tsk(stats, tsk); |
6f44993f | 194 | |
9acc1853 JL |
195 | /* fill in extended acct fields */ |
196 | xacct_add_tsk(stats, tsk); | |
3d9e0cf1 | 197 | } |
9acc1853 | 198 | |
3d9e0cf1 MH |
199 | static int fill_stats_for_pid(pid_t pid, struct taskstats *stats) |
200 | { | |
201 | struct task_struct *tsk; | |
c757249a | 202 | |
3d9e0cf1 MH |
203 | rcu_read_lock(); |
204 | tsk = find_task_by_vpid(pid); | |
205 | if (tsk) | |
206 | get_task_struct(tsk); | |
207 | rcu_read_unlock(); | |
208 | if (!tsk) | |
209 | return -ESRCH; | |
210 | fill_stats(tsk, stats); | |
211 | put_task_struct(tsk); | |
212 | return 0; | |
c757249a SN |
213 | } |
214 | ||
3d9e0cf1 | 215 | static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) |
c757249a | 216 | { |
3d9e0cf1 | 217 | struct task_struct *tsk, *first; |
ad4ecbcb | 218 | unsigned long flags; |
a98b6094 | 219 | int rc = -ESRCH; |
c757249a | 220 | |
ad4ecbcb SN |
221 | /* |
222 | * Add additional stats from live tasks except zombie thread group | |
223 | * leaders who are already counted with the dead tasks | |
224 | */ | |
a98b6094 | 225 | rcu_read_lock(); |
3d9e0cf1 | 226 | first = find_task_by_vpid(tgid); |
ad4ecbcb | 227 | |
a98b6094 ON |
228 | if (!first || !lock_task_sighand(first, &flags)) |
229 | goto out; | |
ad4ecbcb | 230 | |
a98b6094 ON |
231 | if (first->signal->stats) |
232 | memcpy(stats, first->signal->stats, sizeof(*stats)); | |
51de4d90 ON |
233 | else |
234 | memset(stats, 0, sizeof(*stats)); | |
fca178c0 | 235 | |
a98b6094 | 236 | tsk = first; |
c757249a | 237 | do { |
d7c3f5f2 | 238 | if (tsk->exit_state) |
ad4ecbcb | 239 | continue; |
c757249a | 240 | /* |
ad4ecbcb | 241 | * Accounting subsystem can call its functions here to |
c757249a SN |
242 | * fill in relevant parts of struct taskstsats as follows |
243 | * | |
ad4ecbcb | 244 | * per-task-foo(stats, tsk); |
c757249a | 245 | */ |
ad4ecbcb | 246 | delayacct_add_tsk(stats, tsk); |
6f44993f | 247 | |
b663a79c MU |
248 | stats->nvcsw += tsk->nvcsw; |
249 | stats->nivcsw += tsk->nivcsw; | |
c757249a | 250 | } while_each_thread(first, tsk); |
6f44993f | 251 | |
a98b6094 ON |
252 | unlock_task_sighand(first, &flags); |
253 | rc = 0; | |
254 | out: | |
255 | rcu_read_unlock(); | |
256 | ||
257 | stats->version = TASKSTATS_VERSION; | |
c757249a | 258 | /* |
3a4fa0a2 | 259 | * Accounting subsystems can also add calls here to modify |
ad4ecbcb | 260 | * fields of taskstats. |
c757249a | 261 | */ |
a98b6094 | 262 | return rc; |
ad4ecbcb SN |
263 | } |
264 | ||
ad4ecbcb SN |
265 | static void fill_tgid_exit(struct task_struct *tsk) |
266 | { | |
267 | unsigned long flags; | |
268 | ||
b8534d7b | 269 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
ad4ecbcb SN |
270 | if (!tsk->signal->stats) |
271 | goto ret; | |
272 | ||
273 | /* | |
274 | * Each accounting subsystem calls its functions here to | |
275 | * accumalate its per-task stats for tsk, into the per-tgid structure | |
276 | * | |
277 | * per-task-foo(tsk->signal->stats, tsk); | |
278 | */ | |
279 | delayacct_add_tsk(tsk->signal->stats, tsk); | |
280 | ret: | |
b8534d7b | 281 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
ad4ecbcb | 282 | return; |
c757249a SN |
283 | } |
284 | ||
41c7bb95 | 285 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
f9fd8914 SN |
286 | { |
287 | struct listener_list *listeners; | |
288 | struct listener *s, *tmp; | |
289 | unsigned int cpu; | |
ad4ecbcb | 290 | |
41c7bb95 | 291 | if (!cpumask_subset(mask, cpu_possible_mask)) |
f9fd8914 SN |
292 | return -EINVAL; |
293 | ||
294 | if (isadd == REGISTER) { | |
41c7bb95 | 295 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
296 | s = kmalloc_node(sizeof(struct listener), GFP_KERNEL, |
297 | cpu_to_node(cpu)); | |
298 | if (!s) | |
299 | goto cleanup; | |
300 | s->pid = pid; | |
301 | INIT_LIST_HEAD(&s->list); | |
bb129994 | 302 | s->valid = 1; |
f9fd8914 SN |
303 | |
304 | listeners = &per_cpu(listener_array, cpu); | |
305 | down_write(&listeners->sem); | |
306 | list_add(&s->list, &listeners->list); | |
307 | up_write(&listeners->sem); | |
308 | } | |
309 | return 0; | |
310 | } | |
311 | ||
312 | /* Deregister or cleanup */ | |
313 | cleanup: | |
41c7bb95 | 314 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
315 | listeners = &per_cpu(listener_array, cpu); |
316 | down_write(&listeners->sem); | |
317 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
318 | if (s->pid == pid) { | |
319 | list_del(&s->list); | |
320 | kfree(s); | |
321 | break; | |
322 | } | |
323 | } | |
324 | up_write(&listeners->sem); | |
325 | } | |
326 | return 0; | |
327 | } | |
328 | ||
41c7bb95 | 329 | static int parse(struct nlattr *na, struct cpumask *mask) |
f9fd8914 SN |
330 | { |
331 | char *data; | |
332 | int len; | |
333 | int ret; | |
334 | ||
335 | if (na == NULL) | |
336 | return 1; | |
337 | len = nla_len(na); | |
338 | if (len > TASKSTATS_CPUMASK_MAXLEN) | |
339 | return -E2BIG; | |
340 | if (len < 1) | |
341 | return -EINVAL; | |
342 | data = kmalloc(len, GFP_KERNEL); | |
343 | if (!data) | |
344 | return -ENOMEM; | |
345 | nla_strlcpy(data, na, len); | |
29c0177e | 346 | ret = cpulist_parse(data, mask); |
f9fd8914 SN |
347 | kfree(data); |
348 | return ret; | |
349 | } | |
350 | ||
9ab020cf | 351 | #if defined(CONFIG_64BIT) && !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) |
4be2c95d JM |
352 | #define TASKSTATS_NEEDS_PADDING 1 |
353 | #endif | |
354 | ||
51de4d90 | 355 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
68062b86 | 356 | { |
51de4d90 | 357 | struct nlattr *na, *ret; |
68062b86 ON |
358 | int aggr; |
359 | ||
37167485 ON |
360 | aggr = (type == TASKSTATS_TYPE_PID) |
361 | ? TASKSTATS_TYPE_AGGR_PID | |
362 | : TASKSTATS_TYPE_AGGR_TGID; | |
68062b86 | 363 | |
4be2c95d JM |
364 | /* |
365 | * The taskstats structure is internally aligned on 8 byte | |
366 | * boundaries but the layout of the aggregrate reply, with | |
367 | * two NLA headers and the pid (each 4 bytes), actually | |
368 | * force the entire structure to be unaligned. This causes | |
369 | * the kernel to issue unaligned access warnings on some | |
370 | * architectures like ia64. Unfortunately, some software out there | |
371 | * doesn't properly unroll the NLA packet and assumes that the start | |
372 | * of the taskstats structure will always be 20 bytes from the start | |
373 | * of the netlink payload. Aligning the start of the taskstats | |
374 | * structure breaks this software, which we don't want. So, for now | |
375 | * the alignment only happens on architectures that require it | |
376 | * and those users will have to update to fixed versions of those | |
377 | * packages. Space is reserved in the packet only when needed. | |
378 | * This ifdef should be removed in several years e.g. 2012 once | |
379 | * we can be confident that fixed versions are installed on most | |
380 | * systems. We add the padding before the aggregate since the | |
381 | * aggregate is already a defined type. | |
382 | */ | |
383 | #ifdef TASKSTATS_NEEDS_PADDING | |
384 | if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0) | |
385 | goto err; | |
386 | #endif | |
68062b86 | 387 | na = nla_nest_start(skb, aggr); |
37167485 ON |
388 | if (!na) |
389 | goto err; | |
4be2c95d JM |
390 | |
391 | if (nla_put(skb, type, sizeof(pid), &pid) < 0) | |
51de4d90 ON |
392 | goto err; |
393 | ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); | |
394 | if (!ret) | |
395 | goto err; | |
68062b86 ON |
396 | nla_nest_end(skb, na); |
397 | ||
51de4d90 ON |
398 | return nla_data(ret); |
399 | err: | |
400 | return NULL; | |
68062b86 ON |
401 | } |
402 | ||
846c7bb0 BS |
403 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
404 | { | |
405 | int rc = 0; | |
406 | struct sk_buff *rep_skb; | |
407 | struct cgroupstats *stats; | |
408 | struct nlattr *na; | |
409 | size_t size; | |
410 | u32 fd; | |
411 | struct file *file; | |
412 | int fput_needed; | |
413 | ||
414 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; | |
415 | if (!na) | |
416 | return -EINVAL; | |
417 | ||
418 | fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]); | |
419 | file = fget_light(fd, &fput_needed); | |
f9615984 AB |
420 | if (!file) |
421 | return 0; | |
846c7bb0 | 422 | |
f9615984 | 423 | size = nla_total_size(sizeof(struct cgroupstats)); |
846c7bb0 | 424 | |
f9615984 AB |
425 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
426 | size); | |
427 | if (rc < 0) | |
428 | goto err; | |
846c7bb0 | 429 | |
f9615984 AB |
430 | na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS, |
431 | sizeof(struct cgroupstats)); | |
432 | stats = nla_data(na); | |
433 | memset(stats, 0, sizeof(*stats)); | |
846c7bb0 | 434 | |
f9615984 AB |
435 | rc = cgroupstats_build(stats, file->f_dentry); |
436 | if (rc < 0) { | |
437 | nlmsg_free(rep_skb); | |
438 | goto err; | |
846c7bb0 BS |
439 | } |
440 | ||
134e6375 | 441 | rc = send_reply(rep_skb, info); |
f9615984 | 442 | |
846c7bb0 | 443 | err: |
f9615984 | 444 | fput_light(file, fput_needed); |
846c7bb0 BS |
445 | return rc; |
446 | } | |
447 | ||
93233125 | 448 | static int cmd_attr_register_cpumask(struct genl_info *info) |
c757249a | 449 | { |
41c7bb95 | 450 | cpumask_var_t mask; |
93233125 | 451 | int rc; |
41c7bb95 RR |
452 | |
453 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) | |
454 | return -ENOMEM; | |
41c7bb95 | 455 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
f9fd8914 | 456 | if (rc < 0) |
93233125 MH |
457 | goto out; |
458 | rc = add_del_listener(info->snd_pid, mask, REGISTER); | |
459 | out: | |
460 | free_cpumask_var(mask); | |
461 | return rc; | |
462 | } | |
463 | ||
464 | static int cmd_attr_deregister_cpumask(struct genl_info *info) | |
465 | { | |
466 | cpumask_var_t mask; | |
467 | int rc; | |
f9fd8914 | 468 | |
93233125 MH |
469 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
470 | return -ENOMEM; | |
41c7bb95 | 471 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
f9fd8914 | 472 | if (rc < 0) |
93233125 MH |
473 | goto out; |
474 | rc = add_del_listener(info->snd_pid, mask, DEREGISTER); | |
475 | out: | |
41c7bb95 | 476 | free_cpumask_var(mask); |
93233125 MH |
477 | return rc; |
478 | } | |
479 | ||
4be2c95d JM |
480 | static size_t taskstats_packet_size(void) |
481 | { | |
482 | size_t size; | |
483 | ||
484 | size = nla_total_size(sizeof(u32)) + | |
485 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); | |
486 | #ifdef TASKSTATS_NEEDS_PADDING | |
487 | size += nla_total_size(0); /* Padding for alignment */ | |
488 | #endif | |
489 | return size; | |
490 | } | |
491 | ||
93233125 MH |
492 | static int cmd_attr_pid(struct genl_info *info) |
493 | { | |
494 | struct taskstats *stats; | |
495 | struct sk_buff *rep_skb; | |
496 | size_t size; | |
497 | u32 pid; | |
498 | int rc; | |
c757249a | 499 | |
4be2c95d | 500 | size = taskstats_packet_size(); |
c757249a | 501 | |
37167485 | 502 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a SN |
503 | if (rc < 0) |
504 | return rc; | |
505 | ||
51de4d90 | 506 | rc = -EINVAL; |
93233125 MH |
507 | pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
508 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); | |
509 | if (!stats) | |
c757249a | 510 | goto err; |
c757249a | 511 | |
3d9e0cf1 | 512 | rc = fill_stats_for_pid(pid, stats); |
93233125 MH |
513 | if (rc < 0) |
514 | goto err; | |
134e6375 | 515 | return send_reply(rep_skb, info); |
c757249a SN |
516 | err: |
517 | nlmsg_free(rep_skb); | |
518 | return rc; | |
519 | } | |
520 | ||
93233125 MH |
521 | static int cmd_attr_tgid(struct genl_info *info) |
522 | { | |
523 | struct taskstats *stats; | |
524 | struct sk_buff *rep_skb; | |
525 | size_t size; | |
526 | u32 tgid; | |
527 | int rc; | |
528 | ||
4be2c95d | 529 | size = taskstats_packet_size(); |
93233125 MH |
530 | |
531 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); | |
532 | if (rc < 0) | |
533 | return rc; | |
534 | ||
535 | rc = -EINVAL; | |
536 | tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); | |
537 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); | |
538 | if (!stats) | |
539 | goto err; | |
540 | ||
3d9e0cf1 | 541 | rc = fill_stats_for_tgid(tgid, stats); |
93233125 MH |
542 | if (rc < 0) |
543 | goto err; | |
544 | return send_reply(rep_skb, info); | |
545 | err: | |
546 | nlmsg_free(rep_skb); | |
547 | return rc; | |
548 | } | |
549 | ||
550 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) | |
551 | { | |
552 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) | |
553 | return cmd_attr_register_cpumask(info); | |
554 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) | |
555 | return cmd_attr_deregister_cpumask(info); | |
556 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) | |
557 | return cmd_attr_pid(info); | |
558 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) | |
559 | return cmd_attr_tgid(info); | |
560 | else | |
561 | return -EINVAL; | |
562 | } | |
563 | ||
34ec1234 ON |
564 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
565 | { | |
566 | struct signal_struct *sig = tsk->signal; | |
567 | struct taskstats *stats; | |
568 | ||
569 | if (sig->stats || thread_group_empty(tsk)) | |
570 | goto ret; | |
571 | ||
572 | /* No problem if kmem_cache_zalloc() fails */ | |
573 | stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); | |
574 | ||
575 | spin_lock_irq(&tsk->sighand->siglock); | |
576 | if (!sig->stats) { | |
577 | sig->stats = stats; | |
578 | stats = NULL; | |
579 | } | |
580 | spin_unlock_irq(&tsk->sighand->siglock); | |
581 | ||
582 | if (stats) | |
583 | kmem_cache_free(taskstats_cache, stats); | |
584 | ret: | |
585 | return sig->stats; | |
586 | } | |
587 | ||
c757249a | 588 | /* Send pid data out on exit */ |
115085ea | 589 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
c757249a SN |
590 | { |
591 | int rc; | |
115085ea | 592 | struct listener_list *listeners; |
51de4d90 | 593 | struct taskstats *stats; |
c757249a | 594 | struct sk_buff *rep_skb; |
c757249a SN |
595 | size_t size; |
596 | int is_thread_group; | |
c757249a | 597 | |
4a279ff1 | 598 | if (!family_registered) |
c757249a SN |
599 | return; |
600 | ||
c757249a SN |
601 | /* |
602 | * Size includes space for nested attributes | |
603 | */ | |
4be2c95d | 604 | size = taskstats_packet_size(); |
c757249a | 605 | |
34ec1234 | 606 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
4a279ff1 ON |
607 | if (is_thread_group) { |
608 | /* PID + STATS + TGID + STATS */ | |
609 | size = 2 * size; | |
610 | /* fill the tsk->signal->stats structure */ | |
611 | fill_tgid_exit(tsk); | |
612 | } | |
613 | ||
cd85fc58 | 614 | listeners = __this_cpu_ptr(&listener_array); |
115085ea ON |
615 | if (list_empty(&listeners->list)) |
616 | return; | |
617 | ||
37167485 | 618 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a | 619 | if (rc < 0) |
51de4d90 | 620 | return; |
c757249a | 621 | |
51de4d90 ON |
622 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid); |
623 | if (!stats) | |
37167485 | 624 | goto err; |
c757249a | 625 | |
3d9e0cf1 | 626 | fill_stats(tsk, stats); |
c757249a | 627 | |
c757249a | 628 | /* |
ad4ecbcb | 629 | * Doesn't matter if tsk is the leader or the last group member leaving |
c757249a | 630 | */ |
68062b86 | 631 | if (!is_thread_group || !group_dead) |
ad4ecbcb | 632 | goto send; |
c757249a | 633 | |
51de4d90 ON |
634 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid); |
635 | if (!stats) | |
37167485 | 636 | goto err; |
51de4d90 ON |
637 | |
638 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); | |
c757249a | 639 | |
ad4ecbcb | 640 | send: |
115085ea | 641 | send_cpu_listeners(rep_skb, listeners); |
ad4ecbcb | 642 | return; |
37167485 | 643 | err: |
c757249a | 644 | nlmsg_free(rep_skb); |
c757249a SN |
645 | } |
646 | ||
647 | static struct genl_ops taskstats_ops = { | |
648 | .cmd = TASKSTATS_CMD_GET, | |
f9fd8914 | 649 | .doit = taskstats_user_cmd, |
c757249a SN |
650 | .policy = taskstats_cmd_get_policy, |
651 | }; | |
652 | ||
846c7bb0 BS |
653 | static struct genl_ops cgroupstats_ops = { |
654 | .cmd = CGROUPSTATS_CMD_GET, | |
655 | .doit = cgroupstats_user_cmd, | |
656 | .policy = cgroupstats_cmd_get_policy, | |
657 | }; | |
658 | ||
c757249a SN |
659 | /* Needed early in initialization */ |
660 | void __init taskstats_init_early(void) | |
661 | { | |
f9fd8914 SN |
662 | unsigned int i; |
663 | ||
0a31bd5f | 664 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
f9fd8914 SN |
665 | for_each_possible_cpu(i) { |
666 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); | |
667 | init_rwsem(&(per_cpu(listener_array, i).sem)); | |
668 | } | |
c757249a SN |
669 | } |
670 | ||
671 | static int __init taskstats_init(void) | |
672 | { | |
673 | int rc; | |
674 | ||
675 | rc = genl_register_family(&family); | |
676 | if (rc) | |
677 | return rc; | |
678 | ||
679 | rc = genl_register_ops(&family, &taskstats_ops); | |
680 | if (rc < 0) | |
681 | goto err; | |
682 | ||
846c7bb0 BS |
683 | rc = genl_register_ops(&family, &cgroupstats_ops); |
684 | if (rc < 0) | |
685 | goto err_cgroup_ops; | |
686 | ||
c757249a | 687 | family_registered = 1; |
f9b182e2 | 688 | pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
c757249a | 689 | return 0; |
846c7bb0 BS |
690 | err_cgroup_ops: |
691 | genl_unregister_ops(&family, &taskstats_ops); | |
c757249a SN |
692 | err: |
693 | genl_unregister_family(&family); | |
694 | return rc; | |
695 | } | |
696 | ||
697 | /* | |
698 | * late initcall ensures initialization of statistics collection | |
699 | * mechanisms precedes initialization of the taskstats interface | |
700 | */ | |
701 | late_initcall(taskstats_init); |