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 | ||
4be2c95d JM |
352 | #ifdef CONFIG_IA64 |
353 | #define TASKSTATS_NEEDS_PADDING 1 | |
354 | #endif | |
355 | ||
51de4d90 | 356 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
68062b86 | 357 | { |
51de4d90 | 358 | struct nlattr *na, *ret; |
68062b86 ON |
359 | int aggr; |
360 | ||
37167485 ON |
361 | aggr = (type == TASKSTATS_TYPE_PID) |
362 | ? TASKSTATS_TYPE_AGGR_PID | |
363 | : TASKSTATS_TYPE_AGGR_TGID; | |
68062b86 | 364 | |
4be2c95d JM |
365 | /* |
366 | * The taskstats structure is internally aligned on 8 byte | |
367 | * boundaries but the layout of the aggregrate reply, with | |
368 | * two NLA headers and the pid (each 4 bytes), actually | |
369 | * force the entire structure to be unaligned. This causes | |
370 | * the kernel to issue unaligned access warnings on some | |
371 | * architectures like ia64. Unfortunately, some software out there | |
372 | * doesn't properly unroll the NLA packet and assumes that the start | |
373 | * of the taskstats structure will always be 20 bytes from the start | |
374 | * of the netlink payload. Aligning the start of the taskstats | |
375 | * structure breaks this software, which we don't want. So, for now | |
376 | * the alignment only happens on architectures that require it | |
377 | * and those users will have to update to fixed versions of those | |
378 | * packages. Space is reserved in the packet only when needed. | |
379 | * This ifdef should be removed in several years e.g. 2012 once | |
380 | * we can be confident that fixed versions are installed on most | |
381 | * systems. We add the padding before the aggregate since the | |
382 | * aggregate is already a defined type. | |
383 | */ | |
384 | #ifdef TASKSTATS_NEEDS_PADDING | |
385 | if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0) | |
386 | goto err; | |
387 | #endif | |
68062b86 | 388 | na = nla_nest_start(skb, aggr); |
37167485 ON |
389 | if (!na) |
390 | goto err; | |
4be2c95d JM |
391 | |
392 | if (nla_put(skb, type, sizeof(pid), &pid) < 0) | |
51de4d90 ON |
393 | goto err; |
394 | ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); | |
395 | if (!ret) | |
396 | goto err; | |
68062b86 ON |
397 | nla_nest_end(skb, na); |
398 | ||
51de4d90 ON |
399 | return nla_data(ret); |
400 | err: | |
401 | return NULL; | |
68062b86 ON |
402 | } |
403 | ||
846c7bb0 BS |
404 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
405 | { | |
406 | int rc = 0; | |
407 | struct sk_buff *rep_skb; | |
408 | struct cgroupstats *stats; | |
409 | struct nlattr *na; | |
410 | size_t size; | |
411 | u32 fd; | |
412 | struct file *file; | |
413 | int fput_needed; | |
414 | ||
415 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; | |
416 | if (!na) | |
417 | return -EINVAL; | |
418 | ||
419 | fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]); | |
420 | file = fget_light(fd, &fput_needed); | |
f9615984 AB |
421 | if (!file) |
422 | return 0; | |
846c7bb0 | 423 | |
f9615984 | 424 | size = nla_total_size(sizeof(struct cgroupstats)); |
846c7bb0 | 425 | |
f9615984 AB |
426 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
427 | size); | |
428 | if (rc < 0) | |
429 | goto err; | |
846c7bb0 | 430 | |
f9615984 AB |
431 | na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS, |
432 | sizeof(struct cgroupstats)); | |
433 | stats = nla_data(na); | |
434 | memset(stats, 0, sizeof(*stats)); | |
846c7bb0 | 435 | |
f9615984 AB |
436 | rc = cgroupstats_build(stats, file->f_dentry); |
437 | if (rc < 0) { | |
438 | nlmsg_free(rep_skb); | |
439 | goto err; | |
846c7bb0 BS |
440 | } |
441 | ||
134e6375 | 442 | rc = send_reply(rep_skb, info); |
f9615984 | 443 | |
846c7bb0 | 444 | err: |
f9615984 | 445 | fput_light(file, fput_needed); |
846c7bb0 BS |
446 | return rc; |
447 | } | |
448 | ||
93233125 | 449 | static int cmd_attr_register_cpumask(struct genl_info *info) |
c757249a | 450 | { |
41c7bb95 | 451 | cpumask_var_t mask; |
93233125 | 452 | int rc; |
41c7bb95 RR |
453 | |
454 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) | |
455 | return -ENOMEM; | |
41c7bb95 | 456 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
f9fd8914 | 457 | if (rc < 0) |
93233125 MH |
458 | goto out; |
459 | rc = add_del_listener(info->snd_pid, mask, REGISTER); | |
460 | out: | |
461 | free_cpumask_var(mask); | |
462 | return rc; | |
463 | } | |
464 | ||
465 | static int cmd_attr_deregister_cpumask(struct genl_info *info) | |
466 | { | |
467 | cpumask_var_t mask; | |
468 | int rc; | |
f9fd8914 | 469 | |
93233125 MH |
470 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
471 | return -ENOMEM; | |
41c7bb95 | 472 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
f9fd8914 | 473 | if (rc < 0) |
93233125 MH |
474 | goto out; |
475 | rc = add_del_listener(info->snd_pid, mask, DEREGISTER); | |
476 | out: | |
41c7bb95 | 477 | free_cpumask_var(mask); |
93233125 MH |
478 | return rc; |
479 | } | |
480 | ||
4be2c95d JM |
481 | static size_t taskstats_packet_size(void) |
482 | { | |
483 | size_t size; | |
484 | ||
485 | size = nla_total_size(sizeof(u32)) + | |
486 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); | |
487 | #ifdef TASKSTATS_NEEDS_PADDING | |
488 | size += nla_total_size(0); /* Padding for alignment */ | |
489 | #endif | |
490 | return size; | |
491 | } | |
492 | ||
93233125 MH |
493 | static int cmd_attr_pid(struct genl_info *info) |
494 | { | |
495 | struct taskstats *stats; | |
496 | struct sk_buff *rep_skb; | |
497 | size_t size; | |
498 | u32 pid; | |
499 | int rc; | |
c757249a | 500 | |
4be2c95d | 501 | size = taskstats_packet_size(); |
c757249a | 502 | |
37167485 | 503 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a SN |
504 | if (rc < 0) |
505 | return rc; | |
506 | ||
51de4d90 | 507 | rc = -EINVAL; |
93233125 MH |
508 | pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
509 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); | |
510 | if (!stats) | |
c757249a | 511 | goto err; |
c757249a | 512 | |
3d9e0cf1 | 513 | rc = fill_stats_for_pid(pid, stats); |
93233125 MH |
514 | if (rc < 0) |
515 | goto err; | |
134e6375 | 516 | return send_reply(rep_skb, info); |
c757249a SN |
517 | err: |
518 | nlmsg_free(rep_skb); | |
519 | return rc; | |
520 | } | |
521 | ||
93233125 MH |
522 | static int cmd_attr_tgid(struct genl_info *info) |
523 | { | |
524 | struct taskstats *stats; | |
525 | struct sk_buff *rep_skb; | |
526 | size_t size; | |
527 | u32 tgid; | |
528 | int rc; | |
529 | ||
4be2c95d | 530 | size = taskstats_packet_size(); |
93233125 MH |
531 | |
532 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); | |
533 | if (rc < 0) | |
534 | return rc; | |
535 | ||
536 | rc = -EINVAL; | |
537 | tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); | |
538 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); | |
539 | if (!stats) | |
540 | goto err; | |
541 | ||
3d9e0cf1 | 542 | rc = fill_stats_for_tgid(tgid, stats); |
93233125 MH |
543 | if (rc < 0) |
544 | goto err; | |
545 | return send_reply(rep_skb, info); | |
546 | err: | |
547 | nlmsg_free(rep_skb); | |
548 | return rc; | |
549 | } | |
550 | ||
551 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) | |
552 | { | |
553 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) | |
554 | return cmd_attr_register_cpumask(info); | |
555 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) | |
556 | return cmd_attr_deregister_cpumask(info); | |
557 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) | |
558 | return cmd_attr_pid(info); | |
559 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) | |
560 | return cmd_attr_tgid(info); | |
561 | else | |
562 | return -EINVAL; | |
563 | } | |
564 | ||
34ec1234 ON |
565 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
566 | { | |
567 | struct signal_struct *sig = tsk->signal; | |
568 | struct taskstats *stats; | |
569 | ||
570 | if (sig->stats || thread_group_empty(tsk)) | |
571 | goto ret; | |
572 | ||
573 | /* No problem if kmem_cache_zalloc() fails */ | |
574 | stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); | |
575 | ||
576 | spin_lock_irq(&tsk->sighand->siglock); | |
577 | if (!sig->stats) { | |
578 | sig->stats = stats; | |
579 | stats = NULL; | |
580 | } | |
581 | spin_unlock_irq(&tsk->sighand->siglock); | |
582 | ||
583 | if (stats) | |
584 | kmem_cache_free(taskstats_cache, stats); | |
585 | ret: | |
586 | return sig->stats; | |
587 | } | |
588 | ||
c757249a | 589 | /* Send pid data out on exit */ |
115085ea | 590 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
c757249a SN |
591 | { |
592 | int rc; | |
115085ea | 593 | struct listener_list *listeners; |
51de4d90 | 594 | struct taskstats *stats; |
c757249a | 595 | struct sk_buff *rep_skb; |
c757249a SN |
596 | size_t size; |
597 | int is_thread_group; | |
c757249a | 598 | |
4a279ff1 | 599 | if (!family_registered) |
c757249a SN |
600 | return; |
601 | ||
c757249a SN |
602 | /* |
603 | * Size includes space for nested attributes | |
604 | */ | |
4be2c95d | 605 | size = taskstats_packet_size(); |
c757249a | 606 | |
34ec1234 | 607 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
4a279ff1 ON |
608 | if (is_thread_group) { |
609 | /* PID + STATS + TGID + STATS */ | |
610 | size = 2 * size; | |
611 | /* fill the tsk->signal->stats structure */ | |
612 | fill_tgid_exit(tsk); | |
613 | } | |
614 | ||
115085ea ON |
615 | listeners = &__raw_get_cpu_var(listener_array); |
616 | if (list_empty(&listeners->list)) | |
617 | return; | |
618 | ||
37167485 | 619 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a | 620 | if (rc < 0) |
51de4d90 | 621 | return; |
c757249a | 622 | |
51de4d90 ON |
623 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid); |
624 | if (!stats) | |
37167485 | 625 | goto err; |
c757249a | 626 | |
3d9e0cf1 | 627 | fill_stats(tsk, stats); |
c757249a | 628 | |
c757249a | 629 | /* |
ad4ecbcb | 630 | * Doesn't matter if tsk is the leader or the last group member leaving |
c757249a | 631 | */ |
68062b86 | 632 | if (!is_thread_group || !group_dead) |
ad4ecbcb | 633 | goto send; |
c757249a | 634 | |
51de4d90 ON |
635 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid); |
636 | if (!stats) | |
37167485 | 637 | goto err; |
51de4d90 ON |
638 | |
639 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); | |
c757249a | 640 | |
ad4ecbcb | 641 | send: |
115085ea | 642 | send_cpu_listeners(rep_skb, listeners); |
ad4ecbcb | 643 | return; |
37167485 | 644 | err: |
c757249a | 645 | nlmsg_free(rep_skb); |
c757249a SN |
646 | } |
647 | ||
648 | static struct genl_ops taskstats_ops = { | |
649 | .cmd = TASKSTATS_CMD_GET, | |
f9fd8914 | 650 | .doit = taskstats_user_cmd, |
c757249a SN |
651 | .policy = taskstats_cmd_get_policy, |
652 | }; | |
653 | ||
846c7bb0 BS |
654 | static struct genl_ops cgroupstats_ops = { |
655 | .cmd = CGROUPSTATS_CMD_GET, | |
656 | .doit = cgroupstats_user_cmd, | |
657 | .policy = cgroupstats_cmd_get_policy, | |
658 | }; | |
659 | ||
c757249a SN |
660 | /* Needed early in initialization */ |
661 | void __init taskstats_init_early(void) | |
662 | { | |
f9fd8914 SN |
663 | unsigned int i; |
664 | ||
0a31bd5f | 665 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
f9fd8914 SN |
666 | for_each_possible_cpu(i) { |
667 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); | |
668 | init_rwsem(&(per_cpu(listener_array, i).sem)); | |
669 | } | |
c757249a SN |
670 | } |
671 | ||
672 | static int __init taskstats_init(void) | |
673 | { | |
674 | int rc; | |
675 | ||
676 | rc = genl_register_family(&family); | |
677 | if (rc) | |
678 | return rc; | |
679 | ||
680 | rc = genl_register_ops(&family, &taskstats_ops); | |
681 | if (rc < 0) | |
682 | goto err; | |
683 | ||
846c7bb0 BS |
684 | rc = genl_register_ops(&family, &cgroupstats_ops); |
685 | if (rc < 0) | |
686 | goto err_cgroup_ops; | |
687 | ||
c757249a | 688 | family_registered = 1; |
846c7bb0 | 689 | printk("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
c757249a | 690 | return 0; |
846c7bb0 BS |
691 | err_cgroup_ops: |
692 | genl_unregister_ops(&family, &taskstats_ops); | |
c757249a SN |
693 | err: |
694 | genl_unregister_family(&family); | |
695 | return rc; | |
696 | } | |
697 | ||
698 | /* | |
699 | * late initcall ensures initialization of statistics collection | |
700 | * mechanisms precedes initialization of the taskstats interface | |
701 | */ | |
702 | late_initcall(taskstats_init); |