Commit | Line | Data |
---|---|---|
c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
c757249a SN |
2 | /* |
3 | * taskstats.c - Export per-task statistics to userland | |
4 | * | |
5 | * Copyright (C) Shailabh Nagar, IBM Corp. 2006 | |
6 | * (C) Balbir Singh, IBM Corp. 2006 | |
c757249a SN |
7 | */ |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/taskstats_kern.h> | |
f3cef7a9 | 11 | #include <linux/tsacct_kern.h> |
6f44993f | 12 | #include <linux/delayacct.h> |
f9fd8914 SN |
13 | #include <linux/cpumask.h> |
14 | #include <linux/percpu.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
846c7bb0 BS |
16 | #include <linux/cgroupstats.h> |
17 | #include <linux/cgroup.h> | |
18 | #include <linux/fs.h> | |
19 | #include <linux/file.h> | |
4bd6e32a | 20 | #include <linux/pid_namespace.h> |
c757249a | 21 | #include <net/genetlink.h> |
60063497 | 22 | #include <linux/atomic.h> |
8c733420 | 23 | #include <linux/sched/cputime.h> |
c757249a | 24 | |
f9fd8914 SN |
25 | /* |
26 | * Maximum length of a cpumask that can be specified in | |
27 | * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute | |
28 | */ | |
29 | #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS) | |
30 | ||
b81f3ea9 | 31 | static DEFINE_PER_CPU(__u32, taskstats_seqnum); |
c757249a | 32 | static int family_registered; |
e18b890b | 33 | struct kmem_cache *taskstats_cache; |
c757249a | 34 | |
489111e5 | 35 | static struct genl_family family; |
c757249a | 36 | |
b54452b0 | 37 | static const struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = { |
c757249a SN |
38 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
39 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, | |
f9fd8914 SN |
40 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
41 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; | |
42 | ||
243d5212 WC |
43 | /* |
44 | * We have to use TASKSTATS_CMD_ATTR_MAX here, it is the maxattr in the family. | |
45 | * Make sure they are always aligned. | |
46 | */ | |
47 | static const struct nla_policy cgroupstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = { | |
846c7bb0 BS |
48 | [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 }, |
49 | }; | |
50 | ||
f9fd8914 SN |
51 | struct listener { |
52 | struct list_head list; | |
53 | pid_t pid; | |
bb129994 | 54 | char valid; |
c757249a SN |
55 | }; |
56 | ||
f9fd8914 SN |
57 | struct listener_list { |
58 | struct rw_semaphore sem; | |
59 | struct list_head list; | |
60 | }; | |
61 | static DEFINE_PER_CPU(struct listener_list, listener_array); | |
62 | ||
63 | enum actions { | |
64 | REGISTER, | |
65 | DEREGISTER, | |
66 | CPU_DONT_CARE | |
67 | }; | |
c757249a SN |
68 | |
69 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, | |
37167485 | 70 | size_t size) |
c757249a SN |
71 | { |
72 | struct sk_buff *skb; | |
73 | void *reply; | |
74 | ||
75 | /* | |
76 | * If new attributes are added, please revisit this allocation | |
77 | */ | |
3dabc715 | 78 | skb = genlmsg_new(size, GFP_KERNEL); |
c757249a SN |
79 | if (!skb) |
80 | return -ENOMEM; | |
81 | ||
82 | if (!info) { | |
cd85fc58 | 83 | int seq = this_cpu_inc_return(taskstats_seqnum) - 1; |
c757249a | 84 | |
17c157c8 | 85 | reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); |
c757249a | 86 | } else |
17c157c8 | 87 | reply = genlmsg_put_reply(skb, info, &family, 0, cmd); |
c757249a SN |
88 | if (reply == NULL) { |
89 | nlmsg_free(skb); | |
90 | return -EINVAL; | |
91 | } | |
92 | ||
93 | *skbp = skb; | |
c757249a SN |
94 | return 0; |
95 | } | |
96 | ||
f9fd8914 SN |
97 | /* |
98 | * Send taskstats data in @skb to listener with nl_pid @pid | |
99 | */ | |
134e6375 | 100 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
c757249a | 101 | { |
b529ccf2 | 102 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 | 103 | void *reply = genlmsg_data(genlhdr); |
c757249a | 104 | |
053c095a | 105 | genlmsg_end(skb, reply); |
c757249a | 106 | |
134e6375 | 107 | return genlmsg_reply(skb, info); |
c757249a SN |
108 | } |
109 | ||
f9fd8914 SN |
110 | /* |
111 | * Send taskstats data in @skb to listeners registered for @cpu's exit data | |
112 | */ | |
115085ea ON |
113 | static void send_cpu_listeners(struct sk_buff *skb, |
114 | struct listener_list *listeners) | |
f9fd8914 | 115 | { |
b529ccf2 | 116 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 SN |
117 | struct listener *s, *tmp; |
118 | struct sk_buff *skb_next, *skb_cur = skb; | |
119 | void *reply = genlmsg_data(genlhdr); | |
d94a0415 | 120 | int rc, delcount = 0; |
f9fd8914 | 121 | |
053c095a | 122 | genlmsg_end(skb, reply); |
f9fd8914 SN |
123 | |
124 | rc = 0; | |
bb129994 | 125 | down_read(&listeners->sem); |
d94a0415 | 126 | list_for_each_entry(s, &listeners->list, list) { |
f9fd8914 SN |
127 | skb_next = NULL; |
128 | if (!list_is_last(&s->list, &listeners->list)) { | |
129 | skb_next = skb_clone(skb_cur, GFP_KERNEL); | |
d94a0415 | 130 | if (!skb_next) |
f9fd8914 | 131 | break; |
f9fd8914 | 132 | } |
134e6375 | 133 | rc = genlmsg_unicast(&init_net, skb_cur, s->pid); |
d94a0415 | 134 | if (rc == -ECONNREFUSED) { |
bb129994 SN |
135 | s->valid = 0; |
136 | delcount++; | |
f9fd8914 SN |
137 | } |
138 | skb_cur = skb_next; | |
139 | } | |
bb129994 | 140 | up_read(&listeners->sem); |
f9fd8914 | 141 | |
d94a0415 SN |
142 | if (skb_cur) |
143 | nlmsg_free(skb_cur); | |
144 | ||
bb129994 | 145 | if (!delcount) |
d94a0415 | 146 | return; |
bb129994 SN |
147 | |
148 | /* Delete invalidated entries */ | |
149 | down_write(&listeners->sem); | |
150 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
151 | if (!s->valid) { | |
152 | list_del(&s->list); | |
153 | kfree(s); | |
154 | } | |
155 | } | |
156 | up_write(&listeners->sem); | |
f9fd8914 SN |
157 | } |
158 | ||
4bd6e32a EB |
159 | static void fill_stats(struct user_namespace *user_ns, |
160 | struct pid_namespace *pid_ns, | |
161 | struct task_struct *tsk, struct taskstats *stats) | |
c757249a | 162 | { |
51de4d90 | 163 | memset(stats, 0, sizeof(*stats)); |
c757249a SN |
164 | /* |
165 | * Each accounting subsystem adds calls to its functions to | |
166 | * fill in relevant parts of struct taskstsats as follows | |
167 | * | |
7d94dddd | 168 | * per-task-foo(stats, tsk); |
c757249a SN |
169 | */ |
170 | ||
7d94dddd | 171 | delayacct_add_tsk(stats, tsk); |
f3cef7a9 JL |
172 | |
173 | /* fill in basic acct fields */ | |
6f44993f | 174 | stats->version = TASKSTATS_VERSION; |
b663a79c MU |
175 | stats->nvcsw = tsk->nvcsw; |
176 | stats->nivcsw = tsk->nivcsw; | |
4bd6e32a | 177 | bacct_add_tsk(user_ns, pid_ns, stats, tsk); |
6f44993f | 178 | |
9acc1853 JL |
179 | /* fill in extended acct fields */ |
180 | xacct_add_tsk(stats, tsk); | |
3d9e0cf1 | 181 | } |
9acc1853 | 182 | |
3d9e0cf1 MH |
183 | static int fill_stats_for_pid(pid_t pid, struct taskstats *stats) |
184 | { | |
185 | struct task_struct *tsk; | |
c757249a | 186 | |
2ee08260 | 187 | tsk = find_get_task_by_vpid(pid); |
3d9e0cf1 MH |
188 | if (!tsk) |
189 | return -ESRCH; | |
4bd6e32a | 190 | fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats); |
3d9e0cf1 MH |
191 | put_task_struct(tsk); |
192 | return 0; | |
c757249a SN |
193 | } |
194 | ||
3d9e0cf1 | 195 | static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) |
c757249a | 196 | { |
3d9e0cf1 | 197 | struct task_struct *tsk, *first; |
ad4ecbcb | 198 | unsigned long flags; |
a98b6094 | 199 | int rc = -ESRCH; |
8c733420 ZX |
200 | u64 delta, utime, stime; |
201 | u64 start_time; | |
c757249a | 202 | |
ad4ecbcb SN |
203 | /* |
204 | * Add additional stats from live tasks except zombie thread group | |
205 | * leaders who are already counted with the dead tasks | |
206 | */ | |
a98b6094 | 207 | rcu_read_lock(); |
3d9e0cf1 | 208 | first = find_task_by_vpid(tgid); |
ad4ecbcb | 209 | |
a98b6094 ON |
210 | if (!first || !lock_task_sighand(first, &flags)) |
211 | goto out; | |
ad4ecbcb | 212 | |
a98b6094 ON |
213 | if (first->signal->stats) |
214 | memcpy(stats, first->signal->stats, sizeof(*stats)); | |
51de4d90 ON |
215 | else |
216 | memset(stats, 0, sizeof(*stats)); | |
fca178c0 | 217 | |
a98b6094 | 218 | tsk = first; |
8c733420 | 219 | start_time = ktime_get_ns(); |
c757249a | 220 | do { |
d7c3f5f2 | 221 | if (tsk->exit_state) |
ad4ecbcb | 222 | continue; |
c757249a | 223 | /* |
ad4ecbcb | 224 | * Accounting subsystem can call its functions here to |
c757249a SN |
225 | * fill in relevant parts of struct taskstsats as follows |
226 | * | |
ad4ecbcb | 227 | * per-task-foo(stats, tsk); |
c757249a | 228 | */ |
ad4ecbcb | 229 | delayacct_add_tsk(stats, tsk); |
6f44993f | 230 | |
8c733420 ZX |
231 | /* calculate task elapsed time in nsec */ |
232 | delta = start_time - tsk->start_time; | |
233 | /* Convert to micro seconds */ | |
234 | do_div(delta, NSEC_PER_USEC); | |
235 | stats->ac_etime += delta; | |
236 | ||
237 | task_cputime(tsk, &utime, &stime); | |
238 | stats->ac_utime += div_u64(utime, NSEC_PER_USEC); | |
239 | stats->ac_stime += div_u64(stime, NSEC_PER_USEC); | |
240 | ||
b663a79c MU |
241 | stats->nvcsw += tsk->nvcsw; |
242 | stats->nivcsw += tsk->nivcsw; | |
c757249a | 243 | } while_each_thread(first, tsk); |
6f44993f | 244 | |
a98b6094 ON |
245 | unlock_task_sighand(first, &flags); |
246 | rc = 0; | |
247 | out: | |
248 | rcu_read_unlock(); | |
249 | ||
250 | stats->version = TASKSTATS_VERSION; | |
c757249a | 251 | /* |
3a4fa0a2 | 252 | * Accounting subsystems can also add calls here to modify |
ad4ecbcb | 253 | * fields of taskstats. |
c757249a | 254 | */ |
a98b6094 | 255 | return rc; |
ad4ecbcb SN |
256 | } |
257 | ||
ad4ecbcb SN |
258 | static void fill_tgid_exit(struct task_struct *tsk) |
259 | { | |
260 | unsigned long flags; | |
261 | ||
b8534d7b | 262 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
ad4ecbcb SN |
263 | if (!tsk->signal->stats) |
264 | goto ret; | |
265 | ||
266 | /* | |
267 | * Each accounting subsystem calls its functions here to | |
268 | * accumalate its per-task stats for tsk, into the per-tgid structure | |
269 | * | |
270 | * per-task-foo(tsk->signal->stats, tsk); | |
271 | */ | |
272 | delayacct_add_tsk(tsk->signal->stats, tsk); | |
273 | ret: | |
b8534d7b | 274 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
ad4ecbcb | 275 | return; |
c757249a SN |
276 | } |
277 | ||
41c7bb95 | 278 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
f9fd8914 SN |
279 | { |
280 | struct listener_list *listeners; | |
26c4caea | 281 | struct listener *s, *tmp, *s2; |
f9fd8914 | 282 | unsigned int cpu; |
0d20633b | 283 | int ret = 0; |
ad4ecbcb | 284 | |
41c7bb95 | 285 | if (!cpumask_subset(mask, cpu_possible_mask)) |
f9fd8914 SN |
286 | return -EINVAL; |
287 | ||
4bd6e32a EB |
288 | if (current_user_ns() != &init_user_ns) |
289 | return -EINVAL; | |
290 | ||
291 | if (task_active_pid_ns(current) != &init_pid_ns) | |
292 | return -EINVAL; | |
293 | ||
f9fd8914 | 294 | if (isadd == REGISTER) { |
41c7bb95 | 295 | for_each_cpu(cpu, mask) { |
dfc428b6 ON |
296 | s = kmalloc_node(sizeof(struct listener), |
297 | GFP_KERNEL, cpu_to_node(cpu)); | |
0d20633b CG |
298 | if (!s) { |
299 | ret = -ENOMEM; | |
f9fd8914 | 300 | goto cleanup; |
0d20633b | 301 | } |
f9fd8914 | 302 | s->pid = pid; |
bb129994 | 303 | s->valid = 1; |
f9fd8914 SN |
304 | |
305 | listeners = &per_cpu(listener_array, cpu); | |
306 | down_write(&listeners->sem); | |
dfc428b6 | 307 | list_for_each_entry(s2, &listeners->list, list) { |
a7295898 | 308 | if (s2->pid == pid && s2->valid) |
dfc428b6 | 309 | goto exists; |
26c4caea | 310 | } |
f9fd8914 | 311 | list_add(&s->list, &listeners->list); |
26c4caea | 312 | s = NULL; |
dfc428b6 | 313 | exists: |
f9fd8914 | 314 | up_write(&listeners->sem); |
dfc428b6 | 315 | kfree(s); /* nop if NULL */ |
f9fd8914 SN |
316 | } |
317 | return 0; | |
318 | } | |
319 | ||
320 | /* Deregister or cleanup */ | |
321 | cleanup: | |
41c7bb95 | 322 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
323 | listeners = &per_cpu(listener_array, cpu); |
324 | down_write(&listeners->sem); | |
325 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
326 | if (s->pid == pid) { | |
327 | list_del(&s->list); | |
328 | kfree(s); | |
329 | break; | |
330 | } | |
331 | } | |
332 | up_write(&listeners->sem); | |
333 | } | |
0d20633b | 334 | return ret; |
f9fd8914 SN |
335 | } |
336 | ||
41c7bb95 | 337 | static int parse(struct nlattr *na, struct cpumask *mask) |
f9fd8914 SN |
338 | { |
339 | char *data; | |
340 | int len; | |
341 | int ret; | |
342 | ||
343 | if (na == NULL) | |
344 | return 1; | |
345 | len = nla_len(na); | |
346 | if (len > TASKSTATS_CPUMASK_MAXLEN) | |
347 | return -E2BIG; | |
348 | if (len < 1) | |
349 | return -EINVAL; | |
350 | data = kmalloc(len, GFP_KERNEL); | |
351 | if (!data) | |
352 | return -ENOMEM; | |
353 | nla_strlcpy(data, na, len); | |
29c0177e | 354 | ret = cpulist_parse(data, mask); |
f9fd8914 SN |
355 | kfree(data); |
356 | return ret; | |
357 | } | |
358 | ||
51de4d90 | 359 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
68062b86 | 360 | { |
51de4d90 | 361 | struct nlattr *na, *ret; |
68062b86 ON |
362 | int aggr; |
363 | ||
37167485 ON |
364 | aggr = (type == TASKSTATS_TYPE_PID) |
365 | ? TASKSTATS_TYPE_AGGR_PID | |
366 | : TASKSTATS_TYPE_AGGR_TGID; | |
68062b86 | 367 | |
ae0be8de | 368 | na = nla_nest_start_noflag(skb, aggr); |
37167485 ON |
369 | if (!na) |
370 | goto err; | |
4be2c95d | 371 | |
3fa58266 CG |
372 | if (nla_put(skb, type, sizeof(pid), &pid) < 0) { |
373 | nla_nest_cancel(skb, na); | |
51de4d90 | 374 | goto err; |
3fa58266 | 375 | } |
80df5542 ND |
376 | ret = nla_reserve_64bit(skb, TASKSTATS_TYPE_STATS, |
377 | sizeof(struct taskstats), TASKSTATS_TYPE_NULL); | |
3fa58266 CG |
378 | if (!ret) { |
379 | nla_nest_cancel(skb, na); | |
51de4d90 | 380 | goto err; |
3fa58266 | 381 | } |
68062b86 ON |
382 | nla_nest_end(skb, na); |
383 | ||
51de4d90 ON |
384 | return nla_data(ret); |
385 | err: | |
386 | return NULL; | |
68062b86 ON |
387 | } |
388 | ||
846c7bb0 BS |
389 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
390 | { | |
391 | int rc = 0; | |
392 | struct sk_buff *rep_skb; | |
393 | struct cgroupstats *stats; | |
394 | struct nlattr *na; | |
395 | size_t size; | |
396 | u32 fd; | |
2903ff01 | 397 | struct fd f; |
846c7bb0 BS |
398 | |
399 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; | |
400 | if (!na) | |
401 | return -EINVAL; | |
402 | ||
403 | fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]); | |
2903ff01 AV |
404 | f = fdget(fd); |
405 | if (!f.file) | |
f9615984 | 406 | return 0; |
846c7bb0 | 407 | |
f9615984 | 408 | size = nla_total_size(sizeof(struct cgroupstats)); |
846c7bb0 | 409 | |
f9615984 AB |
410 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
411 | size); | |
412 | if (rc < 0) | |
413 | goto err; | |
846c7bb0 | 414 | |
f9615984 AB |
415 | na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS, |
416 | sizeof(struct cgroupstats)); | |
25353b33 | 417 | if (na == NULL) { |
0324b5a4 | 418 | nlmsg_free(rep_skb); |
25353b33 AC |
419 | rc = -EMSGSIZE; |
420 | goto err; | |
421 | } | |
422 | ||
f9615984 AB |
423 | stats = nla_data(na); |
424 | memset(stats, 0, sizeof(*stats)); | |
846c7bb0 | 425 | |
b583043e | 426 | rc = cgroupstats_build(stats, f.file->f_path.dentry); |
f9615984 AB |
427 | if (rc < 0) { |
428 | nlmsg_free(rep_skb); | |
429 | goto err; | |
846c7bb0 BS |
430 | } |
431 | ||
134e6375 | 432 | rc = send_reply(rep_skb, info); |
f9615984 | 433 | |
846c7bb0 | 434 | err: |
2903ff01 | 435 | fdput(f); |
846c7bb0 BS |
436 | return rc; |
437 | } | |
438 | ||
93233125 | 439 | static int cmd_attr_register_cpumask(struct genl_info *info) |
c757249a | 440 | { |
41c7bb95 | 441 | cpumask_var_t mask; |
93233125 | 442 | int rc; |
41c7bb95 RR |
443 | |
444 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) | |
445 | return -ENOMEM; | |
41c7bb95 | 446 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
f9fd8914 | 447 | if (rc < 0) |
93233125 | 448 | goto out; |
15e47304 | 449 | rc = add_del_listener(info->snd_portid, mask, REGISTER); |
93233125 MH |
450 | out: |
451 | free_cpumask_var(mask); | |
452 | return rc; | |
453 | } | |
454 | ||
455 | static int cmd_attr_deregister_cpumask(struct genl_info *info) | |
456 | { | |
457 | cpumask_var_t mask; | |
458 | int rc; | |
f9fd8914 | 459 | |
93233125 MH |
460 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
461 | return -ENOMEM; | |
41c7bb95 | 462 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
f9fd8914 | 463 | if (rc < 0) |
93233125 | 464 | goto out; |
15e47304 | 465 | rc = add_del_listener(info->snd_portid, mask, DEREGISTER); |
93233125 | 466 | out: |
41c7bb95 | 467 | free_cpumask_var(mask); |
93233125 MH |
468 | return rc; |
469 | } | |
470 | ||
4be2c95d JM |
471 | static size_t taskstats_packet_size(void) |
472 | { | |
473 | size_t size; | |
474 | ||
475 | size = nla_total_size(sizeof(u32)) + | |
80df5542 ND |
476 | nla_total_size_64bit(sizeof(struct taskstats)) + |
477 | nla_total_size(0); | |
478 | ||
4be2c95d JM |
479 | return size; |
480 | } | |
481 | ||
93233125 MH |
482 | static int cmd_attr_pid(struct genl_info *info) |
483 | { | |
484 | struct taskstats *stats; | |
485 | struct sk_buff *rep_skb; | |
486 | size_t size; | |
487 | u32 pid; | |
488 | int rc; | |
c757249a | 489 | |
4be2c95d | 490 | size = taskstats_packet_size(); |
c757249a | 491 | |
37167485 | 492 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a SN |
493 | if (rc < 0) |
494 | return rc; | |
495 | ||
51de4d90 | 496 | rc = -EINVAL; |
93233125 MH |
497 | pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
498 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); | |
499 | if (!stats) | |
c757249a | 500 | goto err; |
c757249a | 501 | |
3d9e0cf1 | 502 | rc = fill_stats_for_pid(pid, stats); |
93233125 MH |
503 | if (rc < 0) |
504 | goto err; | |
134e6375 | 505 | return send_reply(rep_skb, info); |
c757249a SN |
506 | err: |
507 | nlmsg_free(rep_skb); | |
508 | return rc; | |
509 | } | |
510 | ||
93233125 MH |
511 | static int cmd_attr_tgid(struct genl_info *info) |
512 | { | |
513 | struct taskstats *stats; | |
514 | struct sk_buff *rep_skb; | |
515 | size_t size; | |
516 | u32 tgid; | |
517 | int rc; | |
518 | ||
4be2c95d | 519 | size = taskstats_packet_size(); |
93233125 MH |
520 | |
521 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); | |
522 | if (rc < 0) | |
523 | return rc; | |
524 | ||
525 | rc = -EINVAL; | |
526 | tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); | |
527 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); | |
528 | if (!stats) | |
529 | goto err; | |
530 | ||
3d9e0cf1 | 531 | rc = fill_stats_for_tgid(tgid, stats); |
93233125 MH |
532 | if (rc < 0) |
533 | goto err; | |
534 | return send_reply(rep_skb, info); | |
535 | err: | |
536 | nlmsg_free(rep_skb); | |
537 | return rc; | |
538 | } | |
539 | ||
540 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) | |
541 | { | |
542 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) | |
543 | return cmd_attr_register_cpumask(info); | |
544 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) | |
545 | return cmd_attr_deregister_cpumask(info); | |
546 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) | |
547 | return cmd_attr_pid(info); | |
548 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) | |
549 | return cmd_attr_tgid(info); | |
550 | else | |
551 | return -EINVAL; | |
552 | } | |
553 | ||
34ec1234 ON |
554 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
555 | { | |
556 | struct signal_struct *sig = tsk->signal; | |
0b8d616f | 557 | struct taskstats *stats_new, *stats; |
34ec1234 | 558 | |
0b8d616f CB |
559 | /* Pairs with smp_store_release() below. */ |
560 | stats = smp_load_acquire(&sig->stats); | |
561 | if (stats || thread_group_empty(tsk)) | |
562 | return stats; | |
34ec1234 ON |
563 | |
564 | /* No problem if kmem_cache_zalloc() fails */ | |
0b8d616f | 565 | stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); |
34ec1234 ON |
566 | |
567 | spin_lock_irq(&tsk->sighand->siglock); | |
0b8d616f CB |
568 | stats = sig->stats; |
569 | if (!stats) { | |
570 | /* | |
571 | * Pairs with smp_store_release() above and order the | |
572 | * kmem_cache_zalloc(). | |
573 | */ | |
574 | smp_store_release(&sig->stats, stats_new); | |
575 | stats = stats_new; | |
576 | stats_new = NULL; | |
34ec1234 ON |
577 | } |
578 | spin_unlock_irq(&tsk->sighand->siglock); | |
579 | ||
0b8d616f CB |
580 | if (stats_new) |
581 | kmem_cache_free(taskstats_cache, stats_new); | |
582 | ||
583 | return stats; | |
34ec1234 ON |
584 | } |
585 | ||
c757249a | 586 | /* Send pid data out on exit */ |
115085ea | 587 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
c757249a SN |
588 | { |
589 | int rc; | |
115085ea | 590 | struct listener_list *listeners; |
51de4d90 | 591 | struct taskstats *stats; |
c757249a | 592 | struct sk_buff *rep_skb; |
c757249a SN |
593 | size_t size; |
594 | int is_thread_group; | |
c757249a | 595 | |
4a279ff1 | 596 | if (!family_registered) |
c757249a SN |
597 | return; |
598 | ||
c757249a SN |
599 | /* |
600 | * Size includes space for nested attributes | |
601 | */ | |
4be2c95d | 602 | size = taskstats_packet_size(); |
c757249a | 603 | |
34ec1234 | 604 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
4a279ff1 ON |
605 | if (is_thread_group) { |
606 | /* PID + STATS + TGID + STATS */ | |
607 | size = 2 * size; | |
608 | /* fill the tsk->signal->stats structure */ | |
609 | fill_tgid_exit(tsk); | |
610 | } | |
611 | ||
4a32fea9 | 612 | listeners = raw_cpu_ptr(&listener_array); |
115085ea ON |
613 | if (list_empty(&listeners->list)) |
614 | return; | |
615 | ||
37167485 | 616 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a | 617 | if (rc < 0) |
51de4d90 | 618 | return; |
c757249a | 619 | |
4bd6e32a EB |
620 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, |
621 | task_pid_nr_ns(tsk, &init_pid_ns)); | |
51de4d90 | 622 | if (!stats) |
37167485 | 623 | goto err; |
c757249a | 624 | |
4bd6e32a | 625 | fill_stats(&init_user_ns, &init_pid_ns, tsk, stats); |
c757249a | 626 | |
c757249a | 627 | /* |
ad4ecbcb | 628 | * Doesn't matter if tsk is the leader or the last group member leaving |
c757249a | 629 | */ |
68062b86 | 630 | if (!is_thread_group || !group_dead) |
ad4ecbcb | 631 | goto send; |
c757249a | 632 | |
4bd6e32a EB |
633 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, |
634 | task_tgid_nr_ns(tsk, &init_pid_ns)); | |
51de4d90 | 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 | ||
4534de83 | 647 | static const struct genl_ops taskstats_ops[] = { |
88d36a99 JB |
648 | { |
649 | .cmd = TASKSTATS_CMD_GET, | |
ef6243ac | 650 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
88d36a99 | 651 | .doit = taskstats_user_cmd, |
3b0f31f2 JB |
652 | /* policy enforced later */ |
653 | .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_HASPOL, | |
88d36a99 JB |
654 | }, |
655 | { | |
656 | .cmd = CGROUPSTATS_CMD_GET, | |
ef6243ac | 657 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
88d36a99 | 658 | .doit = cgroupstats_user_cmd, |
3b0f31f2 JB |
659 | /* policy enforced later */ |
660 | .flags = GENL_CMD_CAP_HASPOL, | |
88d36a99 | 661 | }, |
846c7bb0 BS |
662 | }; |
663 | ||
3b0f31f2 JB |
664 | static int taskstats_pre_doit(const struct genl_ops *ops, struct sk_buff *skb, |
665 | struct genl_info *info) | |
666 | { | |
667 | const struct nla_policy *policy = NULL; | |
668 | ||
669 | switch (ops->cmd) { | |
670 | case TASKSTATS_CMD_GET: | |
671 | policy = taskstats_cmd_get_policy; | |
672 | break; | |
673 | case CGROUPSTATS_CMD_GET: | |
674 | policy = cgroupstats_cmd_get_policy; | |
675 | break; | |
676 | default: | |
677 | return -EINVAL; | |
678 | } | |
679 | ||
8cb08174 JB |
680 | return nlmsg_validate_deprecated(info->nlhdr, GENL_HDRLEN, |
681 | TASKSTATS_CMD_ATTR_MAX, policy, | |
682 | info->extack); | |
3b0f31f2 JB |
683 | } |
684 | ||
56989f6d | 685 | static struct genl_family family __ro_after_init = { |
489111e5 JB |
686 | .name = TASKSTATS_GENL_NAME, |
687 | .version = TASKSTATS_GENL_VERSION, | |
688 | .maxattr = TASKSTATS_CMD_ATTR_MAX, | |
689 | .module = THIS_MODULE, | |
690 | .ops = taskstats_ops, | |
691 | .n_ops = ARRAY_SIZE(taskstats_ops), | |
3b0f31f2 | 692 | .pre_doit = taskstats_pre_doit, |
489111e5 JB |
693 | }; |
694 | ||
c757249a SN |
695 | /* Needed early in initialization */ |
696 | void __init taskstats_init_early(void) | |
697 | { | |
f9fd8914 SN |
698 | unsigned int i; |
699 | ||
0a31bd5f | 700 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
f9fd8914 SN |
701 | for_each_possible_cpu(i) { |
702 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); | |
703 | init_rwsem(&(per_cpu(listener_array, i).sem)); | |
704 | } | |
c757249a SN |
705 | } |
706 | ||
707 | static int __init taskstats_init(void) | |
708 | { | |
709 | int rc; | |
710 | ||
489111e5 | 711 | rc = genl_register_family(&family); |
c757249a SN |
712 | if (rc) |
713 | return rc; | |
714 | ||
c757249a | 715 | family_registered = 1; |
f9b182e2 | 716 | pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
c757249a | 717 | return 0; |
c757249a SN |
718 | } |
719 | ||
720 | /* | |
721 | * late initcall ensures initialization of statistics collection | |
722 | * mechanisms precedes initialization of the taskstats interface | |
723 | */ | |
724 | late_initcall(taskstats_init); |