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> |
0e0af57e | 12 | #include <linux/acct.h> |
6f44993f | 13 | #include <linux/delayacct.h> |
f9fd8914 SN |
14 | #include <linux/cpumask.h> |
15 | #include <linux/percpu.h> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
846c7bb0 BS |
17 | #include <linux/cgroupstats.h> |
18 | #include <linux/cgroup.h> | |
19 | #include <linux/fs.h> | |
20 | #include <linux/file.h> | |
4bd6e32a | 21 | #include <linux/pid_namespace.h> |
c757249a | 22 | #include <net/genetlink.h> |
60063497 | 23 | #include <linux/atomic.h> |
8c733420 | 24 | #include <linux/sched/cputime.h> |
c757249a | 25 | |
f9fd8914 SN |
26 | /* |
27 | * Maximum length of a cpumask that can be specified in | |
28 | * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute | |
29 | */ | |
30 | #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS) | |
31 | ||
b81f3ea9 | 32 | static DEFINE_PER_CPU(__u32, taskstats_seqnum); |
c757249a | 33 | static int family_registered; |
e18b890b | 34 | struct kmem_cache *taskstats_cache; |
c757249a | 35 | |
489111e5 | 36 | static struct genl_family family; |
c757249a | 37 | |
7c1e0926 | 38 | static const struct nla_policy taskstats_cmd_get_policy[] = { |
c757249a SN |
39 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
40 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, | |
f9fd8914 SN |
41 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
42 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; | |
43 | ||
7c1e0926 | 44 | static const struct nla_policy cgroupstats_cmd_get_policy[] = { |
846c7bb0 BS |
45 | [CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 }, |
46 | }; | |
47 | ||
f9fd8914 SN |
48 | struct listener { |
49 | struct list_head list; | |
50 | pid_t pid; | |
bb129994 | 51 | char valid; |
c757249a SN |
52 | }; |
53 | ||
f9fd8914 SN |
54 | struct listener_list { |
55 | struct rw_semaphore sem; | |
56 | struct list_head list; | |
57 | }; | |
58 | static DEFINE_PER_CPU(struct listener_list, listener_array); | |
59 | ||
60 | enum actions { | |
61 | REGISTER, | |
62 | DEREGISTER, | |
63 | CPU_DONT_CARE | |
64 | }; | |
c757249a SN |
65 | |
66 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, | |
37167485 | 67 | size_t size) |
c757249a SN |
68 | { |
69 | struct sk_buff *skb; | |
70 | void *reply; | |
71 | ||
72 | /* | |
73 | * If new attributes are added, please revisit this allocation | |
74 | */ | |
3dabc715 | 75 | skb = genlmsg_new(size, GFP_KERNEL); |
c757249a SN |
76 | if (!skb) |
77 | return -ENOMEM; | |
78 | ||
79 | if (!info) { | |
cd85fc58 | 80 | int seq = this_cpu_inc_return(taskstats_seqnum) - 1; |
c757249a | 81 | |
17c157c8 | 82 | reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); |
c757249a | 83 | } else |
17c157c8 | 84 | reply = genlmsg_put_reply(skb, info, &family, 0, cmd); |
c757249a SN |
85 | if (reply == NULL) { |
86 | nlmsg_free(skb); | |
87 | return -EINVAL; | |
88 | } | |
89 | ||
90 | *skbp = skb; | |
c757249a SN |
91 | return 0; |
92 | } | |
93 | ||
f9fd8914 SN |
94 | /* |
95 | * Send taskstats data in @skb to listener with nl_pid @pid | |
96 | */ | |
134e6375 | 97 | static int send_reply(struct sk_buff *skb, struct genl_info *info) |
c757249a | 98 | { |
b529ccf2 | 99 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 | 100 | void *reply = genlmsg_data(genlhdr); |
c757249a | 101 | |
053c095a | 102 | genlmsg_end(skb, reply); |
c757249a | 103 | |
134e6375 | 104 | return genlmsg_reply(skb, info); |
c757249a SN |
105 | } |
106 | ||
f9fd8914 SN |
107 | /* |
108 | * Send taskstats data in @skb to listeners registered for @cpu's exit data | |
109 | */ | |
115085ea ON |
110 | static void send_cpu_listeners(struct sk_buff *skb, |
111 | struct listener_list *listeners) | |
f9fd8914 | 112 | { |
b529ccf2 | 113 | struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb)); |
f9fd8914 SN |
114 | struct listener *s, *tmp; |
115 | struct sk_buff *skb_next, *skb_cur = skb; | |
116 | void *reply = genlmsg_data(genlhdr); | |
92333baa | 117 | int delcount = 0; |
f9fd8914 | 118 | |
053c095a | 119 | genlmsg_end(skb, reply); |
f9fd8914 | 120 | |
bb129994 | 121 | down_read(&listeners->sem); |
d94a0415 | 122 | list_for_each_entry(s, &listeners->list, list) { |
92333baa LB |
123 | int rc; |
124 | ||
f9fd8914 SN |
125 | skb_next = NULL; |
126 | if (!list_is_last(&s->list, &listeners->list)) { | |
127 | skb_next = skb_clone(skb_cur, GFP_KERNEL); | |
d94a0415 | 128 | if (!skb_next) |
f9fd8914 | 129 | break; |
f9fd8914 | 130 | } |
134e6375 | 131 | rc = genlmsg_unicast(&init_net, skb_cur, s->pid); |
d94a0415 | 132 | if (rc == -ECONNREFUSED) { |
bb129994 SN |
133 | s->valid = 0; |
134 | delcount++; | |
f9fd8914 SN |
135 | } |
136 | skb_cur = skb_next; | |
137 | } | |
bb129994 | 138 | up_read(&listeners->sem); |
f9fd8914 | 139 | |
d94a0415 SN |
140 | if (skb_cur) |
141 | nlmsg_free(skb_cur); | |
142 | ||
bb129994 | 143 | if (!delcount) |
d94a0415 | 144 | return; |
bb129994 SN |
145 | |
146 | /* Delete invalidated entries */ | |
147 | down_write(&listeners->sem); | |
148 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
149 | if (!s->valid) { | |
150 | list_del(&s->list); | |
151 | kfree(s); | |
152 | } | |
153 | } | |
154 | up_write(&listeners->sem); | |
f9fd8914 SN |
155 | } |
156 | ||
0e0af57e DTO |
157 | static void exe_add_tsk(struct taskstats *stats, struct task_struct *tsk) |
158 | { | |
159 | /* No idea if I'm allowed to access that here, now. */ | |
160 | struct file *exe_file = get_task_exe_file(tsk); | |
161 | ||
162 | if (exe_file) { | |
163 | /* Following cp_new_stat64() in stat.c . */ | |
164 | stats->ac_exe_dev = | |
165 | huge_encode_dev(exe_file->f_inode->i_sb->s_dev); | |
166 | stats->ac_exe_inode = exe_file->f_inode->i_ino; | |
167 | fput(exe_file); | |
168 | } else { | |
169 | stats->ac_exe_dev = 0; | |
170 | stats->ac_exe_inode = 0; | |
171 | } | |
172 | } | |
173 | ||
4bd6e32a EB |
174 | static void fill_stats(struct user_namespace *user_ns, |
175 | struct pid_namespace *pid_ns, | |
176 | struct task_struct *tsk, struct taskstats *stats) | |
c757249a | 177 | { |
51de4d90 | 178 | memset(stats, 0, sizeof(*stats)); |
c757249a SN |
179 | /* |
180 | * Each accounting subsystem adds calls to its functions to | |
181 | * fill in relevant parts of struct taskstsats as follows | |
182 | * | |
7d94dddd | 183 | * per-task-foo(stats, tsk); |
c757249a SN |
184 | */ |
185 | ||
7d94dddd | 186 | delayacct_add_tsk(stats, tsk); |
f3cef7a9 JL |
187 | |
188 | /* fill in basic acct fields */ | |
6f44993f | 189 | stats->version = TASKSTATS_VERSION; |
b663a79c MU |
190 | stats->nvcsw = tsk->nvcsw; |
191 | stats->nivcsw = tsk->nivcsw; | |
4bd6e32a | 192 | bacct_add_tsk(user_ns, pid_ns, stats, tsk); |
6f44993f | 193 | |
9acc1853 JL |
194 | /* fill in extended acct fields */ |
195 | xacct_add_tsk(stats, tsk); | |
0e0af57e DTO |
196 | |
197 | /* add executable info */ | |
198 | exe_add_tsk(stats, tsk); | |
3d9e0cf1 | 199 | } |
9acc1853 | 200 | |
3d9e0cf1 MH |
201 | static int fill_stats_for_pid(pid_t pid, struct taskstats *stats) |
202 | { | |
203 | struct task_struct *tsk; | |
c757249a | 204 | |
2ee08260 | 205 | tsk = find_get_task_by_vpid(pid); |
3d9e0cf1 MH |
206 | if (!tsk) |
207 | return -ESRCH; | |
4bd6e32a | 208 | fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats); |
3d9e0cf1 MH |
209 | put_task_struct(tsk); |
210 | return 0; | |
c757249a SN |
211 | } |
212 | ||
3d9e0cf1 | 213 | static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) |
c757249a | 214 | { |
3d9e0cf1 | 215 | struct task_struct *tsk, *first; |
ad4ecbcb | 216 | unsigned long flags; |
a98b6094 | 217 | int rc = -ESRCH; |
8c733420 ZX |
218 | u64 delta, utime, stime; |
219 | u64 start_time; | |
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 | |
8c733420 | 236 | start_time = ktime_get_ns(); |
ed5378a3 | 237 | for_each_thread(first, tsk) { |
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 | |
8c733420 ZX |
248 | /* calculate task elapsed time in nsec */ |
249 | delta = start_time - tsk->start_time; | |
250 | /* Convert to micro seconds */ | |
251 | do_div(delta, NSEC_PER_USEC); | |
252 | stats->ac_etime += delta; | |
253 | ||
254 | task_cputime(tsk, &utime, &stime); | |
255 | stats->ac_utime += div_u64(utime, NSEC_PER_USEC); | |
256 | stats->ac_stime += div_u64(stime, NSEC_PER_USEC); | |
257 | ||
b663a79c MU |
258 | stats->nvcsw += tsk->nvcsw; |
259 | stats->nivcsw += tsk->nivcsw; | |
ed5378a3 | 260 | } |
6f44993f | 261 | |
a98b6094 ON |
262 | unlock_task_sighand(first, &flags); |
263 | rc = 0; | |
264 | out: | |
265 | rcu_read_unlock(); | |
266 | ||
267 | stats->version = TASKSTATS_VERSION; | |
c757249a | 268 | /* |
3a4fa0a2 | 269 | * Accounting subsystems can also add calls here to modify |
ad4ecbcb | 270 | * fields of taskstats. |
c757249a | 271 | */ |
a98b6094 | 272 | return rc; |
ad4ecbcb SN |
273 | } |
274 | ||
ad4ecbcb SN |
275 | static void fill_tgid_exit(struct task_struct *tsk) |
276 | { | |
277 | unsigned long flags; | |
278 | ||
b8534d7b | 279 | spin_lock_irqsave(&tsk->sighand->siglock, flags); |
ad4ecbcb SN |
280 | if (!tsk->signal->stats) |
281 | goto ret; | |
282 | ||
283 | /* | |
284 | * Each accounting subsystem calls its functions here to | |
285 | * accumalate its per-task stats for tsk, into the per-tgid structure | |
286 | * | |
287 | * per-task-foo(tsk->signal->stats, tsk); | |
288 | */ | |
289 | delayacct_add_tsk(tsk->signal->stats, tsk); | |
290 | ret: | |
b8534d7b | 291 | spin_unlock_irqrestore(&tsk->sighand->siglock, flags); |
ad4ecbcb | 292 | return; |
c757249a SN |
293 | } |
294 | ||
41c7bb95 | 295 | static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd) |
f9fd8914 SN |
296 | { |
297 | struct listener_list *listeners; | |
26c4caea | 298 | struct listener *s, *tmp, *s2; |
f9fd8914 | 299 | unsigned int cpu; |
0d20633b | 300 | int ret = 0; |
ad4ecbcb | 301 | |
41c7bb95 | 302 | if (!cpumask_subset(mask, cpu_possible_mask)) |
f9fd8914 SN |
303 | return -EINVAL; |
304 | ||
4bd6e32a EB |
305 | if (current_user_ns() != &init_user_ns) |
306 | return -EINVAL; | |
307 | ||
308 | if (task_active_pid_ns(current) != &init_pid_ns) | |
309 | return -EINVAL; | |
310 | ||
f9fd8914 | 311 | if (isadd == REGISTER) { |
41c7bb95 | 312 | for_each_cpu(cpu, mask) { |
dfc428b6 ON |
313 | s = kmalloc_node(sizeof(struct listener), |
314 | GFP_KERNEL, cpu_to_node(cpu)); | |
0d20633b CG |
315 | if (!s) { |
316 | ret = -ENOMEM; | |
f9fd8914 | 317 | goto cleanup; |
0d20633b | 318 | } |
f9fd8914 | 319 | s->pid = pid; |
bb129994 | 320 | s->valid = 1; |
f9fd8914 SN |
321 | |
322 | listeners = &per_cpu(listener_array, cpu); | |
323 | down_write(&listeners->sem); | |
dfc428b6 | 324 | list_for_each_entry(s2, &listeners->list, list) { |
a7295898 | 325 | if (s2->pid == pid && s2->valid) |
dfc428b6 | 326 | goto exists; |
26c4caea | 327 | } |
f9fd8914 | 328 | list_add(&s->list, &listeners->list); |
26c4caea | 329 | s = NULL; |
dfc428b6 | 330 | exists: |
f9fd8914 | 331 | up_write(&listeners->sem); |
dfc428b6 | 332 | kfree(s); /* nop if NULL */ |
f9fd8914 SN |
333 | } |
334 | return 0; | |
335 | } | |
336 | ||
337 | /* Deregister or cleanup */ | |
338 | cleanup: | |
41c7bb95 | 339 | for_each_cpu(cpu, mask) { |
f9fd8914 SN |
340 | listeners = &per_cpu(listener_array, cpu); |
341 | down_write(&listeners->sem); | |
342 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { | |
343 | if (s->pid == pid) { | |
344 | list_del(&s->list); | |
345 | kfree(s); | |
346 | break; | |
347 | } | |
348 | } | |
349 | up_write(&listeners->sem); | |
350 | } | |
0d20633b | 351 | return ret; |
f9fd8914 SN |
352 | } |
353 | ||
41c7bb95 | 354 | static int parse(struct nlattr *na, struct cpumask *mask) |
f9fd8914 SN |
355 | { |
356 | char *data; | |
357 | int len; | |
358 | int ret; | |
359 | ||
360 | if (na == NULL) | |
361 | return 1; | |
362 | len = nla_len(na); | |
363 | if (len > TASKSTATS_CPUMASK_MAXLEN) | |
364 | return -E2BIG; | |
365 | if (len < 1) | |
366 | return -EINVAL; | |
367 | data = kmalloc(len, GFP_KERNEL); | |
368 | if (!data) | |
369 | return -ENOMEM; | |
872f6903 | 370 | nla_strscpy(data, na, len); |
29c0177e | 371 | ret = cpulist_parse(data, mask); |
f9fd8914 SN |
372 | kfree(data); |
373 | return ret; | |
374 | } | |
375 | ||
51de4d90 | 376 | static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) |
68062b86 | 377 | { |
51de4d90 | 378 | struct nlattr *na, *ret; |
68062b86 ON |
379 | int aggr; |
380 | ||
37167485 ON |
381 | aggr = (type == TASKSTATS_TYPE_PID) |
382 | ? TASKSTATS_TYPE_AGGR_PID | |
383 | : TASKSTATS_TYPE_AGGR_TGID; | |
68062b86 | 384 | |
ae0be8de | 385 | na = nla_nest_start_noflag(skb, aggr); |
37167485 ON |
386 | if (!na) |
387 | goto err; | |
4be2c95d | 388 | |
3fa58266 CG |
389 | if (nla_put(skb, type, sizeof(pid), &pid) < 0) { |
390 | nla_nest_cancel(skb, na); | |
51de4d90 | 391 | goto err; |
3fa58266 | 392 | } |
80df5542 ND |
393 | ret = nla_reserve_64bit(skb, TASKSTATS_TYPE_STATS, |
394 | sizeof(struct taskstats), TASKSTATS_TYPE_NULL); | |
3fa58266 CG |
395 | if (!ret) { |
396 | nla_nest_cancel(skb, na); | |
51de4d90 | 397 | goto err; |
3fa58266 | 398 | } |
68062b86 ON |
399 | nla_nest_end(skb, na); |
400 | ||
51de4d90 ON |
401 | return nla_data(ret); |
402 | err: | |
403 | return NULL; | |
68062b86 ON |
404 | } |
405 | ||
846c7bb0 BS |
406 | static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
407 | { | |
408 | int rc = 0; | |
409 | struct sk_buff *rep_skb; | |
410 | struct cgroupstats *stats; | |
411 | struct nlattr *na; | |
412 | size_t size; | |
413 | u32 fd; | |
2903ff01 | 414 | struct fd f; |
846c7bb0 BS |
415 | |
416 | na = info->attrs[CGROUPSTATS_CMD_ATTR_FD]; | |
417 | if (!na) | |
418 | return -EINVAL; | |
419 | ||
420 | fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]); | |
2903ff01 AV |
421 | f = fdget(fd); |
422 | if (!f.file) | |
f9615984 | 423 | return 0; |
846c7bb0 | 424 | |
f9615984 | 425 | size = nla_total_size(sizeof(struct cgroupstats)); |
846c7bb0 | 426 | |
f9615984 AB |
427 | rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb, |
428 | size); | |
429 | if (rc < 0) | |
430 | goto err; | |
846c7bb0 | 431 | |
f9615984 AB |
432 | na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS, |
433 | sizeof(struct cgroupstats)); | |
25353b33 | 434 | if (na == NULL) { |
0324b5a4 | 435 | nlmsg_free(rep_skb); |
25353b33 AC |
436 | rc = -EMSGSIZE; |
437 | goto err; | |
438 | } | |
439 | ||
f9615984 AB |
440 | stats = nla_data(na); |
441 | memset(stats, 0, sizeof(*stats)); | |
846c7bb0 | 442 | |
b583043e | 443 | rc = cgroupstats_build(stats, f.file->f_path.dentry); |
f9615984 AB |
444 | if (rc < 0) { |
445 | nlmsg_free(rep_skb); | |
446 | goto err; | |
846c7bb0 BS |
447 | } |
448 | ||
134e6375 | 449 | rc = send_reply(rep_skb, info); |
f9615984 | 450 | |
846c7bb0 | 451 | err: |
2903ff01 | 452 | fdput(f); |
846c7bb0 BS |
453 | return rc; |
454 | } | |
455 | ||
93233125 | 456 | static int cmd_attr_register_cpumask(struct genl_info *info) |
c757249a | 457 | { |
41c7bb95 | 458 | cpumask_var_t mask; |
93233125 | 459 | int rc; |
41c7bb95 RR |
460 | |
461 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) | |
462 | return -ENOMEM; | |
41c7bb95 | 463 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask); |
f9fd8914 | 464 | if (rc < 0) |
93233125 | 465 | goto out; |
15e47304 | 466 | rc = add_del_listener(info->snd_portid, mask, REGISTER); |
93233125 MH |
467 | out: |
468 | free_cpumask_var(mask); | |
469 | return rc; | |
470 | } | |
471 | ||
472 | static int cmd_attr_deregister_cpumask(struct genl_info *info) | |
473 | { | |
474 | cpumask_var_t mask; | |
475 | int rc; | |
f9fd8914 | 476 | |
93233125 MH |
477 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
478 | return -ENOMEM; | |
41c7bb95 | 479 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask); |
f9fd8914 | 480 | if (rc < 0) |
93233125 | 481 | goto out; |
15e47304 | 482 | rc = add_del_listener(info->snd_portid, mask, DEREGISTER); |
93233125 | 483 | out: |
41c7bb95 | 484 | free_cpumask_var(mask); |
93233125 MH |
485 | return rc; |
486 | } | |
487 | ||
4be2c95d JM |
488 | static size_t taskstats_packet_size(void) |
489 | { | |
490 | size_t size; | |
491 | ||
492 | size = nla_total_size(sizeof(u32)) + | |
80df5542 ND |
493 | nla_total_size_64bit(sizeof(struct taskstats)) + |
494 | nla_total_size(0); | |
495 | ||
4be2c95d JM |
496 | return size; |
497 | } | |
498 | ||
93233125 MH |
499 | static int cmd_attr_pid(struct genl_info *info) |
500 | { | |
501 | struct taskstats *stats; | |
502 | struct sk_buff *rep_skb; | |
503 | size_t size; | |
504 | u32 pid; | |
505 | int rc; | |
c757249a | 506 | |
4be2c95d | 507 | size = taskstats_packet_size(); |
c757249a | 508 | |
37167485 | 509 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a SN |
510 | if (rc < 0) |
511 | return rc; | |
512 | ||
51de4d90 | 513 | rc = -EINVAL; |
93233125 MH |
514 | pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
515 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid); | |
516 | if (!stats) | |
c757249a | 517 | goto err; |
c757249a | 518 | |
3d9e0cf1 | 519 | rc = fill_stats_for_pid(pid, stats); |
93233125 MH |
520 | if (rc < 0) |
521 | goto err; | |
134e6375 | 522 | return send_reply(rep_skb, info); |
c757249a SN |
523 | err: |
524 | nlmsg_free(rep_skb); | |
525 | return rc; | |
526 | } | |
527 | ||
93233125 MH |
528 | static int cmd_attr_tgid(struct genl_info *info) |
529 | { | |
530 | struct taskstats *stats; | |
531 | struct sk_buff *rep_skb; | |
532 | size_t size; | |
533 | u32 tgid; | |
534 | int rc; | |
535 | ||
4be2c95d | 536 | size = taskstats_packet_size(); |
93233125 MH |
537 | |
538 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); | |
539 | if (rc < 0) | |
540 | return rc; | |
541 | ||
542 | rc = -EINVAL; | |
543 | tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); | |
544 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid); | |
545 | if (!stats) | |
546 | goto err; | |
547 | ||
3d9e0cf1 | 548 | rc = fill_stats_for_tgid(tgid, stats); |
93233125 MH |
549 | if (rc < 0) |
550 | goto err; | |
551 | return send_reply(rep_skb, info); | |
552 | err: | |
553 | nlmsg_free(rep_skb); | |
554 | return rc; | |
555 | } | |
556 | ||
557 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) | |
558 | { | |
559 | if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK]) | |
560 | return cmd_attr_register_cpumask(info); | |
561 | else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK]) | |
562 | return cmd_attr_deregister_cpumask(info); | |
563 | else if (info->attrs[TASKSTATS_CMD_ATTR_PID]) | |
564 | return cmd_attr_pid(info); | |
565 | else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) | |
566 | return cmd_attr_tgid(info); | |
567 | else | |
568 | return -EINVAL; | |
569 | } | |
570 | ||
34ec1234 ON |
571 | static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) |
572 | { | |
573 | struct signal_struct *sig = tsk->signal; | |
0b8d616f | 574 | struct taskstats *stats_new, *stats; |
34ec1234 | 575 | |
0b8d616f CB |
576 | /* Pairs with smp_store_release() below. */ |
577 | stats = smp_load_acquire(&sig->stats); | |
578 | if (stats || thread_group_empty(tsk)) | |
579 | return stats; | |
34ec1234 ON |
580 | |
581 | /* No problem if kmem_cache_zalloc() fails */ | |
0b8d616f | 582 | stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); |
34ec1234 ON |
583 | |
584 | spin_lock_irq(&tsk->sighand->siglock); | |
0b8d616f CB |
585 | stats = sig->stats; |
586 | if (!stats) { | |
587 | /* | |
588 | * Pairs with smp_store_release() above and order the | |
589 | * kmem_cache_zalloc(). | |
590 | */ | |
591 | smp_store_release(&sig->stats, stats_new); | |
592 | stats = stats_new; | |
593 | stats_new = NULL; | |
34ec1234 ON |
594 | } |
595 | spin_unlock_irq(&tsk->sighand->siglock); | |
596 | ||
0b8d616f CB |
597 | if (stats_new) |
598 | kmem_cache_free(taskstats_cache, stats_new); | |
599 | ||
600 | return stats; | |
34ec1234 ON |
601 | } |
602 | ||
c757249a | 603 | /* Send pid data out on exit */ |
115085ea | 604 | void taskstats_exit(struct task_struct *tsk, int group_dead) |
c757249a SN |
605 | { |
606 | int rc; | |
115085ea | 607 | struct listener_list *listeners; |
51de4d90 | 608 | struct taskstats *stats; |
c757249a | 609 | struct sk_buff *rep_skb; |
c757249a SN |
610 | size_t size; |
611 | int is_thread_group; | |
c757249a | 612 | |
4a279ff1 | 613 | if (!family_registered) |
c757249a SN |
614 | return; |
615 | ||
c757249a SN |
616 | /* |
617 | * Size includes space for nested attributes | |
618 | */ | |
4be2c95d | 619 | size = taskstats_packet_size(); |
c757249a | 620 | |
34ec1234 | 621 | is_thread_group = !!taskstats_tgid_alloc(tsk); |
4a279ff1 ON |
622 | if (is_thread_group) { |
623 | /* PID + STATS + TGID + STATS */ | |
624 | size = 2 * size; | |
625 | /* fill the tsk->signal->stats structure */ | |
626 | fill_tgid_exit(tsk); | |
627 | } | |
628 | ||
4a32fea9 | 629 | listeners = raw_cpu_ptr(&listener_array); |
115085ea ON |
630 | if (list_empty(&listeners->list)) |
631 | return; | |
632 | ||
37167485 | 633 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); |
c757249a | 634 | if (rc < 0) |
51de4d90 | 635 | return; |
c757249a | 636 | |
4bd6e32a EB |
637 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, |
638 | task_pid_nr_ns(tsk, &init_pid_ns)); | |
51de4d90 | 639 | if (!stats) |
37167485 | 640 | goto err; |
c757249a | 641 | |
4bd6e32a | 642 | fill_stats(&init_user_ns, &init_pid_ns, tsk, stats); |
0e0af57e DTO |
643 | if (group_dead) |
644 | stats->ac_flag |= AGROUP; | |
c757249a | 645 | |
c757249a | 646 | /* |
ad4ecbcb | 647 | * Doesn't matter if tsk is the leader or the last group member leaving |
c757249a | 648 | */ |
68062b86 | 649 | if (!is_thread_group || !group_dead) |
ad4ecbcb | 650 | goto send; |
c757249a | 651 | |
4bd6e32a EB |
652 | stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, |
653 | task_tgid_nr_ns(tsk, &init_pid_ns)); | |
51de4d90 | 654 | if (!stats) |
37167485 | 655 | goto err; |
51de4d90 ON |
656 | |
657 | memcpy(stats, tsk->signal->stats, sizeof(*stats)); | |
c757249a | 658 | |
ad4ecbcb | 659 | send: |
115085ea | 660 | send_cpu_listeners(rep_skb, listeners); |
ad4ecbcb | 661 | return; |
37167485 | 662 | err: |
c757249a | 663 | nlmsg_free(rep_skb); |
c757249a SN |
664 | } |
665 | ||
7c1e0926 | 666 | static const struct genl_ops taskstats_ops[] = { |
88d36a99 JB |
667 | { |
668 | .cmd = TASKSTATS_CMD_GET, | |
ef6243ac | 669 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
88d36a99 | 670 | .doit = taskstats_user_cmd, |
7c1e0926 JK |
671 | .policy = taskstats_cmd_get_policy, |
672 | .maxattr = ARRAY_SIZE(taskstats_cmd_get_policy) - 1, | |
673 | .flags = GENL_ADMIN_PERM, | |
88d36a99 JB |
674 | }, |
675 | { | |
676 | .cmd = CGROUPSTATS_CMD_GET, | |
ef6243ac | 677 | .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, |
88d36a99 | 678 | .doit = cgroupstats_user_cmd, |
7c1e0926 JK |
679 | .policy = cgroupstats_cmd_get_policy, |
680 | .maxattr = ARRAY_SIZE(cgroupstats_cmd_get_policy) - 1, | |
88d36a99 | 681 | }, |
846c7bb0 BS |
682 | }; |
683 | ||
56989f6d | 684 | static struct genl_family family __ro_after_init = { |
489111e5 JB |
685 | .name = TASKSTATS_GENL_NAME, |
686 | .version = TASKSTATS_GENL_VERSION, | |
489111e5 | 687 | .module = THIS_MODULE, |
7c1e0926 JK |
688 | .ops = taskstats_ops, |
689 | .n_ops = ARRAY_SIZE(taskstats_ops), | |
9c5d03d3 | 690 | .resv_start_op = CGROUPSTATS_CMD_GET + 1, |
edc73c72 | 691 | .netnsok = true, |
489111e5 JB |
692 | }; |
693 | ||
c757249a SN |
694 | /* Needed early in initialization */ |
695 | void __init taskstats_init_early(void) | |
696 | { | |
f9fd8914 SN |
697 | unsigned int i; |
698 | ||
0a31bd5f | 699 | taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC); |
f9fd8914 SN |
700 | for_each_possible_cpu(i) { |
701 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); | |
702 | init_rwsem(&(per_cpu(listener_array, i).sem)); | |
703 | } | |
c757249a SN |
704 | } |
705 | ||
706 | static int __init taskstats_init(void) | |
707 | { | |
708 | int rc; | |
709 | ||
489111e5 | 710 | rc = genl_register_family(&family); |
c757249a SN |
711 | if (rc) |
712 | return rc; | |
713 | ||
c757249a | 714 | family_registered = 1; |
f9b182e2 | 715 | pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); |
c757249a | 716 | return 0; |
c757249a SN |
717 | } |
718 | ||
719 | /* | |
720 | * late initcall ensures initialization of statistics collection | |
721 | * mechanisms precedes initialization of the taskstats interface | |
722 | */ | |
723 | late_initcall(taskstats_init); |