Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 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> |
Shailabh Nagar | 6f44993 | 2006-07-14 00:24:41 -0700 | [diff] [blame] | 21 | #include <linux/delayacct.h> |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 22 | #include <linux/cpumask.h> |
| 23 | #include <linux/percpu.h> |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 24 | #include <net/genetlink.h> |
| 25 | #include <asm/atomic.h> |
| 26 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 27 | /* |
| 28 | * Maximum length of a cpumask that can be specified in |
| 29 | * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute |
| 30 | */ |
| 31 | #define TASKSTATS_CPUMASK_MAXLEN (100+6*NR_CPUS) |
| 32 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 33 | static DEFINE_PER_CPU(__u32, taskstats_seqnum) = { 0 }; |
| 34 | static int family_registered; |
| 35 | kmem_cache_t *taskstats_cache; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 36 | |
| 37 | static struct genl_family family = { |
| 38 | .id = GENL_ID_GENERATE, |
| 39 | .name = TASKSTATS_GENL_NAME, |
| 40 | .version = TASKSTATS_GENL_VERSION, |
| 41 | .maxattr = TASKSTATS_CMD_ATTR_MAX, |
| 42 | }; |
| 43 | |
| 44 | static struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] |
| 45 | __read_mostly = { |
| 46 | [TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 }, |
| 47 | [TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 }, |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 48 | [TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING }, |
| 49 | [TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },}; |
| 50 | |
| 51 | struct listener { |
| 52 | struct list_head list; |
| 53 | pid_t pid; |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 54 | char valid; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 55 | }; |
| 56 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 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 | }; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 68 | |
| 69 | static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, |
| 70 | void **replyp, size_t size) |
| 71 | { |
| 72 | struct sk_buff *skb; |
| 73 | void *reply; |
| 74 | |
| 75 | /* |
| 76 | * If new attributes are added, please revisit this allocation |
| 77 | */ |
| 78 | skb = nlmsg_new(size); |
| 79 | if (!skb) |
| 80 | return -ENOMEM; |
| 81 | |
| 82 | if (!info) { |
| 83 | int seq = get_cpu_var(taskstats_seqnum)++; |
| 84 | put_cpu_var(taskstats_seqnum); |
| 85 | |
| 86 | reply = genlmsg_put(skb, 0, seq, |
| 87 | family.id, 0, 0, |
| 88 | cmd, family.version); |
| 89 | } else |
| 90 | reply = genlmsg_put(skb, info->snd_pid, info->snd_seq, |
| 91 | family.id, 0, 0, |
| 92 | cmd, family.version); |
| 93 | if (reply == NULL) { |
| 94 | nlmsg_free(skb); |
| 95 | return -EINVAL; |
| 96 | } |
| 97 | |
| 98 | *skbp = skb; |
| 99 | *replyp = reply; |
| 100 | return 0; |
| 101 | } |
| 102 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 103 | /* |
| 104 | * Send taskstats data in @skb to listener with nl_pid @pid |
| 105 | */ |
| 106 | static int send_reply(struct sk_buff *skb, pid_t pid) |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 107 | { |
| 108 | struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data); |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 109 | void *reply = genlmsg_data(genlhdr); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 110 | int rc; |
| 111 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 112 | rc = genlmsg_end(skb, reply); |
| 113 | if (rc < 0) { |
| 114 | nlmsg_free(skb); |
| 115 | return rc; |
| 116 | } |
| 117 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 118 | return genlmsg_unicast(skb, pid); |
| 119 | } |
| 120 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 121 | /* |
| 122 | * Send taskstats data in @skb to listeners registered for @cpu's exit data |
| 123 | */ |
| 124 | static int send_cpu_listeners(struct sk_buff *skb, unsigned int cpu) |
| 125 | { |
| 126 | struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data); |
| 127 | struct listener_list *listeners; |
| 128 | struct listener *s, *tmp; |
| 129 | struct sk_buff *skb_next, *skb_cur = skb; |
| 130 | void *reply = genlmsg_data(genlhdr); |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 131 | int rc, ret, delcount = 0; |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 132 | |
| 133 | rc = genlmsg_end(skb, reply); |
| 134 | if (rc < 0) { |
| 135 | nlmsg_free(skb); |
| 136 | return rc; |
| 137 | } |
| 138 | |
| 139 | rc = 0; |
| 140 | listeners = &per_cpu(listener_array, cpu); |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 141 | down_read(&listeners->sem); |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 142 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
| 143 | skb_next = NULL; |
| 144 | if (!list_is_last(&s->list, &listeners->list)) { |
| 145 | skb_next = skb_clone(skb_cur, GFP_KERNEL); |
| 146 | if (!skb_next) { |
| 147 | nlmsg_free(skb_cur); |
| 148 | rc = -ENOMEM; |
| 149 | break; |
| 150 | } |
| 151 | } |
| 152 | ret = genlmsg_unicast(skb_cur, s->pid); |
| 153 | if (ret == -ECONNREFUSED) { |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 154 | s->valid = 0; |
| 155 | delcount++; |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 156 | rc = ret; |
| 157 | } |
| 158 | skb_cur = skb_next; |
| 159 | } |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 160 | up_read(&listeners->sem); |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 161 | |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 162 | if (!delcount) |
| 163 | return rc; |
| 164 | |
| 165 | /* Delete invalidated entries */ |
| 166 | down_write(&listeners->sem); |
| 167 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
| 168 | if (!s->valid) { |
| 169 | list_del(&s->list); |
| 170 | kfree(s); |
| 171 | } |
| 172 | } |
| 173 | up_write(&listeners->sem); |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 174 | return rc; |
| 175 | } |
| 176 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 177 | static int fill_pid(pid_t pid, struct task_struct *pidtsk, |
| 178 | struct taskstats *stats) |
| 179 | { |
Shailabh Nagar | 7d94ddd | 2006-07-30 03:03:10 -0700 | [diff] [blame^] | 180 | int rc = 0; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 181 | struct task_struct *tsk = pidtsk; |
| 182 | |
| 183 | if (!pidtsk) { |
| 184 | read_lock(&tasklist_lock); |
| 185 | tsk = find_task_by_pid(pid); |
| 186 | if (!tsk) { |
| 187 | read_unlock(&tasklist_lock); |
| 188 | return -ESRCH; |
| 189 | } |
| 190 | get_task_struct(tsk); |
| 191 | read_unlock(&tasklist_lock); |
| 192 | } else |
| 193 | get_task_struct(tsk); |
| 194 | |
| 195 | /* |
| 196 | * Each accounting subsystem adds calls to its functions to |
| 197 | * fill in relevant parts of struct taskstsats as follows |
| 198 | * |
Shailabh Nagar | 7d94ddd | 2006-07-30 03:03:10 -0700 | [diff] [blame^] | 199 | * per-task-foo(stats, tsk); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 200 | */ |
| 201 | |
Shailabh Nagar | 7d94ddd | 2006-07-30 03:03:10 -0700 | [diff] [blame^] | 202 | delayacct_add_tsk(stats, tsk); |
Shailabh Nagar | 6f44993 | 2006-07-14 00:24:41 -0700 | [diff] [blame] | 203 | stats->version = TASKSTATS_VERSION; |
| 204 | |
| 205 | /* Define err: label here if needed */ |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 206 | put_task_struct(tsk); |
| 207 | return rc; |
| 208 | |
| 209 | } |
| 210 | |
| 211 | static int fill_tgid(pid_t tgid, struct task_struct *tgidtsk, |
| 212 | struct taskstats *stats) |
| 213 | { |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 214 | struct task_struct *tsk, *first; |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 215 | unsigned long flags; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 216 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 217 | /* |
| 218 | * Add additional stats from live tasks except zombie thread group |
| 219 | * leaders who are already counted with the dead tasks |
| 220 | */ |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 221 | first = tgidtsk; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 222 | if (!first) { |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 223 | read_lock(&tasklist_lock); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 224 | first = find_task_by_pid(tgid); |
| 225 | if (!first) { |
| 226 | read_unlock(&tasklist_lock); |
| 227 | return -ESRCH; |
| 228 | } |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 229 | get_task_struct(first); |
| 230 | read_unlock(&tasklist_lock); |
| 231 | } else |
| 232 | get_task_struct(first); |
| 233 | |
| 234 | /* Start with stats from dead tasks */ |
| 235 | spin_lock_irqsave(&first->signal->stats_lock, flags); |
| 236 | if (first->signal->stats) |
| 237 | memcpy(stats, first->signal->stats, sizeof(*stats)); |
| 238 | spin_unlock_irqrestore(&first->signal->stats_lock, flags); |
| 239 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 240 | tsk = first; |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 241 | read_lock(&tasklist_lock); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 242 | do { |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 243 | if (tsk->exit_state == EXIT_ZOMBIE && thread_group_leader(tsk)) |
| 244 | continue; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 245 | /* |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 246 | * Accounting subsystem can call its functions here to |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 247 | * fill in relevant parts of struct taskstsats as follows |
| 248 | * |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 249 | * per-task-foo(stats, tsk); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 250 | */ |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 251 | delayacct_add_tsk(stats, tsk); |
Shailabh Nagar | 6f44993 | 2006-07-14 00:24:41 -0700 | [diff] [blame] | 252 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 253 | } while_each_thread(first, tsk); |
| 254 | read_unlock(&tasklist_lock); |
Shailabh Nagar | 6f44993 | 2006-07-14 00:24:41 -0700 | [diff] [blame] | 255 | stats->version = TASKSTATS_VERSION; |
| 256 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 257 | /* |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 258 | * Accounting subsytems can also add calls here to modify |
| 259 | * fields of taskstats. |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 260 | */ |
| 261 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 262 | return 0; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 263 | } |
| 264 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 265 | |
| 266 | static void fill_tgid_exit(struct task_struct *tsk) |
| 267 | { |
| 268 | unsigned long flags; |
| 269 | |
| 270 | spin_lock_irqsave(&tsk->signal->stats_lock, flags); |
| 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: |
| 282 | spin_unlock_irqrestore(&tsk->signal->stats_lock, flags); |
| 283 | return; |
| 284 | } |
| 285 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 286 | static int add_del_listener(pid_t pid, cpumask_t *maskp, int isadd) |
| 287 | { |
| 288 | struct listener_list *listeners; |
| 289 | struct listener *s, *tmp; |
| 290 | unsigned int cpu; |
| 291 | cpumask_t mask = *maskp; |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 292 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 293 | if (!cpus_subset(mask, cpu_possible_map)) |
| 294 | return -EINVAL; |
| 295 | |
| 296 | if (isadd == REGISTER) { |
| 297 | for_each_cpu_mask(cpu, mask) { |
| 298 | s = kmalloc_node(sizeof(struct listener), GFP_KERNEL, |
| 299 | cpu_to_node(cpu)); |
| 300 | if (!s) |
| 301 | goto cleanup; |
| 302 | s->pid = pid; |
| 303 | INIT_LIST_HEAD(&s->list); |
Shailabh Nagar | bb12999 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 304 | s->valid = 1; |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 305 | |
| 306 | listeners = &per_cpu(listener_array, cpu); |
| 307 | down_write(&listeners->sem); |
| 308 | list_add(&s->list, &listeners->list); |
| 309 | up_write(&listeners->sem); |
| 310 | } |
| 311 | return 0; |
| 312 | } |
| 313 | |
| 314 | /* Deregister or cleanup */ |
| 315 | cleanup: |
| 316 | for_each_cpu_mask(cpu, mask) { |
| 317 | listeners = &per_cpu(listener_array, cpu); |
| 318 | down_write(&listeners->sem); |
| 319 | list_for_each_entry_safe(s, tmp, &listeners->list, list) { |
| 320 | if (s->pid == pid) { |
| 321 | list_del(&s->list); |
| 322 | kfree(s); |
| 323 | break; |
| 324 | } |
| 325 | } |
| 326 | up_write(&listeners->sem); |
| 327 | } |
| 328 | return 0; |
| 329 | } |
| 330 | |
| 331 | static int parse(struct nlattr *na, cpumask_t *mask) |
| 332 | { |
| 333 | char *data; |
| 334 | int len; |
| 335 | int ret; |
| 336 | |
| 337 | if (na == NULL) |
| 338 | return 1; |
| 339 | len = nla_len(na); |
| 340 | if (len > TASKSTATS_CPUMASK_MAXLEN) |
| 341 | return -E2BIG; |
| 342 | if (len < 1) |
| 343 | return -EINVAL; |
| 344 | data = kmalloc(len, GFP_KERNEL); |
| 345 | if (!data) |
| 346 | return -ENOMEM; |
| 347 | nla_strlcpy(data, na, len); |
| 348 | ret = cpulist_parse(data, *mask); |
| 349 | kfree(data); |
| 350 | return ret; |
| 351 | } |
| 352 | |
| 353 | static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 354 | { |
| 355 | int rc = 0; |
| 356 | struct sk_buff *rep_skb; |
| 357 | struct taskstats stats; |
| 358 | void *reply; |
| 359 | size_t size; |
| 360 | struct nlattr *na; |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 361 | cpumask_t mask; |
| 362 | |
| 363 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], &mask); |
| 364 | if (rc < 0) |
| 365 | return rc; |
| 366 | if (rc == 0) |
| 367 | return add_del_listener(info->snd_pid, &mask, REGISTER); |
| 368 | |
| 369 | rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], &mask); |
| 370 | if (rc < 0) |
| 371 | return rc; |
| 372 | if (rc == 0) |
| 373 | return add_del_listener(info->snd_pid, &mask, DEREGISTER); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 374 | |
| 375 | /* |
| 376 | * Size includes space for nested attributes |
| 377 | */ |
| 378 | size = nla_total_size(sizeof(u32)) + |
| 379 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); |
| 380 | |
| 381 | memset(&stats, 0, sizeof(stats)); |
| 382 | rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, &reply, size); |
| 383 | if (rc < 0) |
| 384 | return rc; |
| 385 | |
| 386 | if (info->attrs[TASKSTATS_CMD_ATTR_PID]) { |
| 387 | u32 pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]); |
| 388 | rc = fill_pid(pid, NULL, &stats); |
| 389 | if (rc < 0) |
| 390 | goto err; |
| 391 | |
| 392 | na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_PID); |
| 393 | NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_PID, pid); |
| 394 | NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS, |
| 395 | stats); |
| 396 | } else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) { |
| 397 | u32 tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]); |
| 398 | rc = fill_tgid(tgid, NULL, &stats); |
| 399 | if (rc < 0) |
| 400 | goto err; |
| 401 | |
| 402 | na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_TGID); |
| 403 | NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_TGID, tgid); |
| 404 | NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS, |
| 405 | stats); |
| 406 | } else { |
| 407 | rc = -EINVAL; |
| 408 | goto err; |
| 409 | } |
| 410 | |
| 411 | nla_nest_end(rep_skb, na); |
| 412 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 413 | return send_reply(rep_skb, info->snd_pid); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 414 | |
| 415 | nla_put_failure: |
| 416 | return genlmsg_cancel(rep_skb, reply); |
| 417 | err: |
| 418 | nlmsg_free(rep_skb); |
| 419 | return rc; |
| 420 | } |
| 421 | |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 422 | void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu) |
| 423 | { |
| 424 | struct listener_list *listeners; |
| 425 | struct taskstats *tmp; |
| 426 | /* |
| 427 | * This is the cpu on which the task is exiting currently and will |
| 428 | * be the one for which the exit event is sent, even if the cpu |
| 429 | * on which this function is running changes later. |
| 430 | */ |
| 431 | *mycpu = raw_smp_processor_id(); |
| 432 | |
| 433 | *ptidstats = NULL; |
| 434 | tmp = kmem_cache_zalloc(taskstats_cache, SLAB_KERNEL); |
| 435 | if (!tmp) |
| 436 | return; |
| 437 | |
| 438 | listeners = &per_cpu(listener_array, *mycpu); |
| 439 | down_read(&listeners->sem); |
| 440 | if (!list_empty(&listeners->list)) { |
| 441 | *ptidstats = tmp; |
| 442 | tmp = NULL; |
| 443 | } |
| 444 | up_read(&listeners->sem); |
| 445 | kfree(tmp); |
| 446 | } |
| 447 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 448 | /* Send pid data out on exit */ |
| 449 | void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats, |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 450 | int group_dead, unsigned int mycpu) |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 451 | { |
| 452 | int rc; |
| 453 | struct sk_buff *rep_skb; |
| 454 | void *reply; |
| 455 | size_t size; |
| 456 | int is_thread_group; |
| 457 | struct nlattr *na; |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 458 | unsigned long flags; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 459 | |
| 460 | if (!family_registered || !tidstats) |
| 461 | return; |
| 462 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 463 | spin_lock_irqsave(&tsk->signal->stats_lock, flags); |
| 464 | is_thread_group = tsk->signal->stats ? 1 : 0; |
| 465 | spin_unlock_irqrestore(&tsk->signal->stats_lock, flags); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 466 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 467 | rc = 0; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 468 | /* |
| 469 | * Size includes space for nested attributes |
| 470 | */ |
| 471 | size = nla_total_size(sizeof(u32)) + |
| 472 | nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); |
| 473 | |
| 474 | if (is_thread_group) |
| 475 | size = 2 * size; /* PID + STATS + TGID + STATS */ |
| 476 | |
| 477 | rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, &reply, size); |
| 478 | if (rc < 0) |
| 479 | goto ret; |
| 480 | |
| 481 | rc = fill_pid(tsk->pid, tsk, tidstats); |
| 482 | if (rc < 0) |
| 483 | goto err_skb; |
| 484 | |
| 485 | na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_PID); |
| 486 | NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_PID, (u32)tsk->pid); |
| 487 | NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS, |
| 488 | *tidstats); |
| 489 | nla_nest_end(rep_skb, na); |
| 490 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 491 | if (!is_thread_group) |
| 492 | goto send; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 493 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 494 | /* |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 495 | * tsk has/had a thread group so fill the tsk->signal->stats structure |
| 496 | * Doesn't matter if tsk is the leader or the last group member leaving |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 497 | */ |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 498 | |
| 499 | fill_tgid_exit(tsk); |
| 500 | if (!group_dead) |
| 501 | goto send; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 502 | |
| 503 | na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_TGID); |
| 504 | NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_TGID, (u32)tsk->tgid); |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 505 | /* No locking needed for tsk->signal->stats since group is dead */ |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 506 | NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS, |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 507 | *tsk->signal->stats); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 508 | nla_nest_end(rep_skb, na); |
| 509 | |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 510 | send: |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 511 | send_cpu_listeners(rep_skb, mycpu); |
Shailabh Nagar | ad4ecbc | 2006-07-14 00:24:44 -0700 | [diff] [blame] | 512 | return; |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 513 | |
| 514 | nla_put_failure: |
| 515 | genlmsg_cancel(rep_skb, reply); |
| 516 | goto ret; |
| 517 | err_skb: |
| 518 | nlmsg_free(rep_skb); |
| 519 | ret: |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 520 | return; |
| 521 | } |
| 522 | |
| 523 | static struct genl_ops taskstats_ops = { |
| 524 | .cmd = TASKSTATS_CMD_GET, |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 525 | .doit = taskstats_user_cmd, |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 526 | .policy = taskstats_cmd_get_policy, |
| 527 | }; |
| 528 | |
| 529 | /* Needed early in initialization */ |
| 530 | void __init taskstats_init_early(void) |
| 531 | { |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 532 | unsigned int i; |
| 533 | |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 534 | taskstats_cache = kmem_cache_create("taskstats_cache", |
| 535 | sizeof(struct taskstats), |
| 536 | 0, SLAB_PANIC, NULL, NULL); |
Shailabh Nagar | f9fd891 | 2006-07-14 00:24:47 -0700 | [diff] [blame] | 537 | for_each_possible_cpu(i) { |
| 538 | INIT_LIST_HEAD(&(per_cpu(listener_array, i).list)); |
| 539 | init_rwsem(&(per_cpu(listener_array, i).sem)); |
| 540 | } |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 541 | } |
| 542 | |
| 543 | static int __init taskstats_init(void) |
| 544 | { |
| 545 | int rc; |
| 546 | |
| 547 | rc = genl_register_family(&family); |
| 548 | if (rc) |
| 549 | return rc; |
| 550 | |
| 551 | rc = genl_register_ops(&family, &taskstats_ops); |
| 552 | if (rc < 0) |
| 553 | goto err; |
| 554 | |
| 555 | family_registered = 1; |
| 556 | return 0; |
| 557 | err: |
| 558 | genl_unregister_family(&family); |
| 559 | return rc; |
| 560 | } |
| 561 | |
| 562 | /* |
| 563 | * late initcall ensures initialization of statistics collection |
| 564 | * mechanisms precedes initialization of the taskstats interface |
| 565 | */ |
| 566 | late_initcall(taskstats_init); |