1/* getdelays.c 2 * 3 * Utility to get per-pid and per-tgid delay accounting statistics 4 * Also illustrates usage of the taskstats interface 5 * 6 * Copyright (C) Shailabh Nagar, IBM Corp. 2005 7 * Copyright (C) Balbir Singh, IBM Corp. 2006 8 * Copyright (c) Jay Lan, SGI. 2006 9 * 10 * Compile with 11 * gcc -I/usr/src/linux/include getdelays.c -o getdelays 12 */ 13 14#include <stdio.h> 15#include <stdlib.h> 16#include <errno.h> 17#include <unistd.h> 18#include <poll.h> 19#include <string.h> 20#include <fcntl.h> 21#include <sys/types.h> 22#include <sys/stat.h> 23#include <sys/socket.h> 24#include <sys/types.h> 25#include <signal.h> 26 27#include <linux/genetlink.h> 28#include <linux/taskstats.h> 29 30/* 31 * Generic macros for dealing with netlink sockets. Might be duplicated 32 * elsewhere. It is recommended that commercial grade applications use 33 * libnl or libnetlink and use the interfaces provided by the library 34 */ 35#define GENLMSG_DATA(glh) ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN)) 36#define GENLMSG_PAYLOAD(glh) (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN) 37#define NLA_DATA(na) ((void *)((char*)(na) + NLA_HDRLEN)) 38#define NLA_PAYLOAD(len) (len - NLA_HDRLEN) 39 40#define err(code, fmt, arg...) \ 41 do { \ 42 fprintf(stderr, fmt, ##arg); \ 43 exit(code); \ 44 } while (0) 45 46int done; 47int rcvbufsz; 48char name[100]; 49int dbg; 50int print_delays; 51int print_io_accounting; 52__u64 stime, utime; 53 54#define PRINTF(fmt, arg...) { \ 55 if (dbg) { \ 56 printf(fmt, ##arg); \ 57 } \ 58 } 59 60/* Maximum size of response requested or message sent */ 61#define MAX_MSG_SIZE 1024 62/* Maximum number of cpus expected to be specified in a cpumask */ 63#define MAX_CPUS 32 64 65struct msgtemplate { 66 struct nlmsghdr n; 67 struct genlmsghdr g; 68 char buf[MAX_MSG_SIZE]; 69}; 70 71char cpumask[100+6*MAX_CPUS]; 72 73static void usage(void) 74{ 75 fprintf(stderr, "getdelays [-dilv] [-w logfile] [-r bufsize] " 76 "[-m cpumask] [-t tgid] [-p pid]\n"); 77 fprintf(stderr, " -d: print delayacct stats\n"); 78 fprintf(stderr, " -i: print IO accounting (works only with -p)\n"); 79 fprintf(stderr, " -l: listen forever\n"); 80 fprintf(stderr, " -v: debug on\n"); 81} 82 83/* 84 * Create a raw netlink socket and bind 85 */ 86static int create_nl_socket(int protocol) 87{ 88 int fd; 89 struct sockaddr_nl local; 90 91 fd = socket(AF_NETLINK, SOCK_RAW, protocol); 92 if (fd < 0) 93 return -1; 94 95 if (rcvbufsz) 96 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, 97 &rcvbufsz, sizeof(rcvbufsz)) < 0) { 98 fprintf(stderr, "Unable to set socket rcv buf size " 99 "to %d\n", 100 rcvbufsz); 101 return -1; 102 } 103 104 memset(&local, 0, sizeof(local)); 105 local.nl_family = AF_NETLINK; 106 107 if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0) 108 goto error; 109 110 return fd; 111error: 112 close(fd); 113 return -1; 114} 115 116 117int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid, 118 __u8 genl_cmd, __u16 nla_type, 119 void *nla_data, int nla_len) 120{ 121 struct nlattr *na; 122 struct sockaddr_nl nladdr; 123 int r, buflen; 124 char *buf; 125 126 struct msgtemplate msg; 127 128 msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN); 129 msg.n.nlmsg_type = nlmsg_type; 130 msg.n.nlmsg_flags = NLM_F_REQUEST; 131 msg.n.nlmsg_seq = 0; 132 msg.n.nlmsg_pid = nlmsg_pid; 133 msg.g.cmd = genl_cmd; 134 msg.g.version = 0x1; 135 na = (struct nlattr *) GENLMSG_DATA(&msg); 136 na->nla_type = nla_type; 137 na->nla_len = nla_len + 1 + NLA_HDRLEN; 138 memcpy(NLA_DATA(na), nla_data, nla_len); 139 msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len); 140 141 buf = (char *) &msg; 142 buflen = msg.n.nlmsg_len ; 143 memset(&nladdr, 0, sizeof(nladdr)); 144 nladdr.nl_family = AF_NETLINK; 145 while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr, 146 sizeof(nladdr))) < buflen) { 147 if (r > 0) { 148 buf += r; 149 buflen -= r; 150 } else if (errno != EAGAIN) 151 return -1; 152 } 153 return 0; 154} 155 156 157/* 158 * Probe the controller in genetlink to find the family id 159 * for the TASKSTATS family 160 */ 161int get_family_id(int sd) 162{ 163 struct { 164 struct nlmsghdr n; 165 struct genlmsghdr g; 166 char buf[256]; 167 } ans; 168 169 int id, rc; 170 struct nlattr *na; 171 int rep_len; 172 173 strcpy(name, TASKSTATS_GENL_NAME); 174 rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY, 175 CTRL_ATTR_FAMILY_NAME, (void *)name, 176 strlen(TASKSTATS_GENL_NAME)+1); 177 178 rep_len = recv(sd, &ans, sizeof(ans), 0); 179 if (ans.n.nlmsg_type == NLMSG_ERROR || 180 (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len)) 181 return 0; 182 183 na = (struct nlattr *) GENLMSG_DATA(&ans); 184 na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len)); 185 if (na->nla_type == CTRL_ATTR_FAMILY_ID) { 186 id = *(__u16 *) NLA_DATA(na); 187 } 188 return id; 189} 190 191void print_delayacct(struct taskstats *t) 192{ 193 printf("\n\nCPU %15s%15s%15s%15s\n" 194 " %15llu%15llu%15llu%15llu\n" 195 "IO %15s%15s\n" 196 " %15llu%15llu\n" 197 "MEM %15s%15s\n" 198 " %15llu%15llu\n\n", 199 "count", "real total", "virtual total", "delay total", 200 t->cpu_count, t->cpu_run_real_total, t->cpu_run_virtual_total, 201 t->cpu_delay_total, 202 "count", "delay total", 203 t->blkio_count, t->blkio_delay_total, 204 "count", "delay total", t->swapin_count, t->swapin_delay_total); 205} 206 207void print_ioacct(struct taskstats *t) 208{ 209 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n", 210 t->ac_comm, 211 (unsigned long long)t->read_bytes, 212 (unsigned long long)t->write_bytes, 213 (unsigned long long)t->cancelled_write_bytes); 214} 215 216int main(int argc, char *argv[]) 217{ 218 int c, rc, rep_len, aggr_len, len2, cmd_type; 219 __u16 id; 220 __u32 mypid; 221 222 struct nlattr *na; 223 int nl_sd = -1; 224 int len = 0; 225 pid_t tid = 0; 226 pid_t rtid = 0; 227 228 int fd = 0; 229 int count = 0; 230 int write_file = 0; 231 int maskset = 0; 232 char *logfile = NULL; 233 int loop = 0; 234 235 struct msgtemplate msg; 236 237 while (1) { 238 c = getopt(argc, argv, "diw:r:m:t:p:vl"); 239 if (c < 0) 240 break; 241 242 switch (c) { 243 case 'd': 244 printf("print delayacct stats ON\n"); 245 print_delays = 1; 246 break; 247 case 'i': 248 printf("printing IO accounting\n"); 249 print_io_accounting = 1; 250 break; 251 case 'w': 252 logfile = strdup(optarg); 253 printf("write to file %s\n", logfile); 254 write_file = 1; 255 break; 256 case 'r': 257 rcvbufsz = atoi(optarg); 258 printf("receive buf size %d\n", rcvbufsz); 259 if (rcvbufsz < 0) 260 err(1, "Invalid rcv buf size\n"); 261 break; 262 case 'm': 263 strncpy(cpumask, optarg, sizeof(cpumask)); 264 maskset = 1; 265 printf("cpumask %s maskset %d\n", cpumask, maskset); 266 break; 267 case 't': 268 tid = atoi(optarg); 269 if (!tid) 270 err(1, "Invalid tgid\n"); 271 cmd_type = TASKSTATS_CMD_ATTR_TGID; 272 break; 273 case 'p': 274 tid = atoi(optarg); 275 if (!tid) 276 err(1, "Invalid pid\n"); 277 cmd_type = TASKSTATS_CMD_ATTR_PID; 278 break; 279 case 'v': 280 printf("debug on\n"); 281 dbg = 1; 282 break; 283 case 'l': 284 printf("listen forever\n"); 285 loop = 1; 286 break; 287 default: 288 usage(); 289 exit(-1); 290 } 291 } 292 293 if (write_file) { 294 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, 295 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 296 if (fd == -1) { 297 perror("Cannot open output file\n"); 298 exit(1); 299 } 300 } 301 302 if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0) 303 err(1, "error creating Netlink socket\n"); 304 305 306 mypid = getpid(); 307 id = get_family_id(nl_sd); 308 if (!id) { 309 fprintf(stderr, "Error getting family id, errno %d\n", errno); 310 goto err; 311 } 312 PRINTF("family id %d\n", id); 313 314 if (maskset) { 315 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 316 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK, 317 &cpumask, strlen(cpumask) + 1); 318 PRINTF("Sent register cpumask, retval %d\n", rc); 319 if (rc < 0) { 320 fprintf(stderr, "error sending register cpumask\n"); 321 goto err; 322 } 323 } 324 325 if (tid) { 326 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 327 cmd_type, &tid, sizeof(__u32)); 328 PRINTF("Sent pid/tgid, retval %d\n", rc); 329 if (rc < 0) { 330 fprintf(stderr, "error sending tid/tgid cmd\n"); 331 goto done; 332 } 333 } 334 335 do { 336 int i; 337 338 rep_len = recv(nl_sd, &msg, sizeof(msg), 0); 339 PRINTF("received %d bytes\n", rep_len); 340 341 if (rep_len < 0) { 342 fprintf(stderr, "nonfatal reply error: errno %d\n", 343 errno); 344 continue; 345 } 346 if (msg.n.nlmsg_type == NLMSG_ERROR || 347 !NLMSG_OK((&msg.n), rep_len)) { 348 struct nlmsgerr *err = NLMSG_DATA(&msg); 349 fprintf(stderr, "fatal reply error, errno %d\n", 350 err->error); 351 goto done; 352 } 353 354 PRINTF("nlmsghdr size=%d, nlmsg_len=%d, rep_len=%d\n", 355 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len); 356 357 358 rep_len = GENLMSG_PAYLOAD(&msg.n); 359 360 na = (struct nlattr *) GENLMSG_DATA(&msg); 361 len = 0; 362 i = 0; 363 while (len < rep_len) { 364 len += NLA_ALIGN(na->nla_len); 365 switch (na->nla_type) { 366 case TASKSTATS_TYPE_AGGR_TGID: 367 /* Fall through */ 368 case TASKSTATS_TYPE_AGGR_PID: 369 aggr_len = NLA_PAYLOAD(na->nla_len); 370 len2 = 0; 371 /* For nested attributes, na follows */ 372 na = (struct nlattr *) NLA_DATA(na); 373 done = 0; 374 while (len2 < aggr_len) { 375 switch (na->nla_type) { 376 case TASKSTATS_TYPE_PID: 377 rtid = *(int *) NLA_DATA(na); 378 if (print_delays) 379 printf("PID\t%d\n", rtid); 380 break; 381 case TASKSTATS_TYPE_TGID: 382 rtid = *(int *) NLA_DATA(na); 383 if (print_delays) 384 printf("TGID\t%d\n", rtid); 385 break; 386 case TASKSTATS_TYPE_STATS: 387 count++; 388 if (print_delays) 389 print_delayacct((struct taskstats *) NLA_DATA(na)); 390 if (print_io_accounting) 391 print_ioacct((struct taskstats *) NLA_DATA(na)); 392 if (fd) { 393 if (write(fd, NLA_DATA(na), na->nla_len) < 0) { 394 err(1,"write error\n"); 395 } 396 } 397 if (!loop) 398 goto done; 399 break; 400 default: 401 fprintf(stderr, "Unknown nested" 402 " nla_type %d\n", 403 na->nla_type); 404 break; 405 } 406 len2 += NLA_ALIGN(na->nla_len); 407 na = (struct nlattr *) ((char *) na + len2); 408 } 409 break; 410 411 default: 412 fprintf(stderr, "Unknown nla_type %d\n", 413 na->nla_type); 414 break; 415 } 416 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len); 417 } 418 } while (loop); 419done: 420 if (maskset) { 421 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 422 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK, 423 &cpumask, strlen(cpumask) + 1); 424 printf("Sent deregister mask, retval %d\n", rc); 425 if (rc < 0) 426 err(rc, "error sending deregister cpumask\n"); 427 } 428err: 429 close(nl_sd); 430 if (fd) 431 close(fd); 432 return 0; 433} 434