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/wait.h> 25 #include <signal.h> 26 27 #include <linux/genetlink.h> 28 #include <linux/taskstats.h> 29 #include <linux/cgroupstats.h> 30 31 /* 32 * Generic macros for dealing with netlink sockets. Might be duplicated 33 * elsewhere. It is recommended that commercial grade applications use 34 * libnl or libnetlink and use the interfaces provided by the library 35 */ 36 #define GENLMSG_DATA(glh) ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN)) 37 #define GENLMSG_PAYLOAD(glh) (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN) 38 #define NLA_DATA(na) ((void *)((char*)(na) + NLA_HDRLEN)) 39 #define NLA_PAYLOAD(len) (len - NLA_HDRLEN) 40 41 #define err(code, fmt, arg...) \ 42 do { \ 43 fprintf(stderr, fmt, ##arg); \ 44 exit(code); \ 45 } while (0) 46 47 int done; 48 int rcvbufsz; 49 char name[100]; 50 int dbg; 51 int print_delays; 52 int print_io_accounting; 53 int print_task_context_switch_counts; 54 55 #define PRINTF(fmt, arg...) { \ 56 if (dbg) { \ 57 printf(fmt, ##arg); \ 58 } \ 59 } 60 61 /* Maximum size of response requested or message sent */ 62 #define MAX_MSG_SIZE 1024 63 /* Maximum number of cpus expected to be specified in a cpumask */ 64 #define MAX_CPUS 32 65 66 struct msgtemplate { 67 struct nlmsghdr n; 68 struct genlmsghdr g; 69 char buf[MAX_MSG_SIZE]; 70 }; 71 72 char cpumask[100+6*MAX_CPUS]; 73 74 static void usage(void) 75 { 76 fprintf(stderr, "getdelays [-dilv] [-w logfile] [-r bufsize] " 77 "[-m cpumask] [-t tgid] [-p pid]\n"); 78 fprintf(stderr, " -d: print delayacct stats\n"); 79 fprintf(stderr, " -i: print IO accounting (works only with -p)\n"); 80 fprintf(stderr, " -l: listen forever\n"); 81 fprintf(stderr, " -v: debug on\n"); 82 fprintf(stderr, " -C: container path\n"); 83 } 84 85 /* 86 * Create a raw netlink socket and bind 87 */ 88 static int create_nl_socket(int protocol) 89 { 90 int fd; 91 struct sockaddr_nl local; 92 93 fd = socket(AF_NETLINK, SOCK_RAW, protocol); 94 if (fd < 0) 95 return -1; 96 97 if (rcvbufsz) 98 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, 99 &rcvbufsz, sizeof(rcvbufsz)) < 0) { 100 fprintf(stderr, "Unable to set socket rcv buf size to %d\n", 101 rcvbufsz); 102 goto error; 103 } 104 105 memset(&local, 0, sizeof(local)); 106 local.nl_family = AF_NETLINK; 107 108 if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0) 109 goto error; 110 111 return fd; 112 error: 113 close(fd); 114 return -1; 115 } 116 117 118 static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid, 119 __u8 genl_cmd, __u16 nla_type, 120 void *nla_data, int nla_len) 121 { 122 struct nlattr *na; 123 struct sockaddr_nl nladdr; 124 int r, buflen; 125 char *buf; 126 127 struct msgtemplate msg; 128 129 msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN); 130 msg.n.nlmsg_type = nlmsg_type; 131 msg.n.nlmsg_flags = NLM_F_REQUEST; 132 msg.n.nlmsg_seq = 0; 133 msg.n.nlmsg_pid = nlmsg_pid; 134 msg.g.cmd = genl_cmd; 135 msg.g.version = 0x1; 136 na = (struct nlattr *) GENLMSG_DATA(&msg); 137 na->nla_type = nla_type; 138 na->nla_len = nla_len + 1 + NLA_HDRLEN; 139 memcpy(NLA_DATA(na), nla_data, nla_len); 140 msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len); 141 142 buf = (char *) &msg; 143 buflen = msg.n.nlmsg_len ; 144 memset(&nladdr, 0, sizeof(nladdr)); 145 nladdr.nl_family = AF_NETLINK; 146 while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr, 147 sizeof(nladdr))) < buflen) { 148 if (r > 0) { 149 buf += r; 150 buflen -= r; 151 } else if (errno != EAGAIN) 152 return -1; 153 } 154 return 0; 155 } 156 157 158 /* 159 * Probe the controller in genetlink to find the family id 160 * for the TASKSTATS family 161 */ 162 static int get_family_id(int sd) 163 { 164 struct { 165 struct nlmsghdr n; 166 struct genlmsghdr g; 167 char buf[256]; 168 } ans; 169 170 int id = 0, rc; 171 struct nlattr *na; 172 int rep_len; 173 174 strcpy(name, TASKSTATS_GENL_NAME); 175 rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY, 176 CTRL_ATTR_FAMILY_NAME, (void *)name, 177 strlen(TASKSTATS_GENL_NAME)+1); 178 if (rc < 0) 179 return 0; /* sendto() failure? */ 180 181 rep_len = recv(sd, &ans, sizeof(ans), 0); 182 if (ans.n.nlmsg_type == NLMSG_ERROR || 183 (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len)) 184 return 0; 185 186 na = (struct nlattr *) GENLMSG_DATA(&ans); 187 na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len)); 188 if (na->nla_type == CTRL_ATTR_FAMILY_ID) { 189 id = *(__u16 *) NLA_DATA(na); 190 } 191 return id; 192 } 193 194 #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1)) 195 196 static void print_delayacct(struct taskstats *t) 197 { 198 printf("\n\nCPU %15s%15s%15s%15s%15s\n" 199 " %15llu%15llu%15llu%15llu%15.3fms\n" 200 "IO %15s%15s%15s\n" 201 " %15llu%15llu%15llums\n" 202 "SWAP %15s%15s%15s\n" 203 " %15llu%15llu%15llums\n" 204 "RECLAIM %12s%15s%15s\n" 205 " %15llu%15llu%15llums\n", 206 "count", "real total", "virtual total", 207 "delay total", "delay average", 208 (unsigned long long)t->cpu_count, 209 (unsigned long long)t->cpu_run_real_total, 210 (unsigned long long)t->cpu_run_virtual_total, 211 (unsigned long long)t->cpu_delay_total, 212 average_ms((double)t->cpu_delay_total, t->cpu_count), 213 "count", "delay total", "delay average", 214 (unsigned long long)t->blkio_count, 215 (unsigned long long)t->blkio_delay_total, 216 average_ms(t->blkio_delay_total, t->blkio_count), 217 "count", "delay total", "delay average", 218 (unsigned long long)t->swapin_count, 219 (unsigned long long)t->swapin_delay_total, 220 average_ms(t->swapin_delay_total, t->swapin_count), 221 "count", "delay total", "delay average", 222 (unsigned long long)t->freepages_count, 223 (unsigned long long)t->freepages_delay_total, 224 average_ms(t->freepages_delay_total, t->freepages_count)); 225 } 226 227 static void task_context_switch_counts(struct taskstats *t) 228 { 229 printf("\n\nTask %15s%15s\n" 230 " %15llu%15llu\n", 231 "voluntary", "nonvoluntary", 232 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw); 233 } 234 235 static void print_cgroupstats(struct cgroupstats *c) 236 { 237 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, " 238 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping, 239 (unsigned long long)c->nr_io_wait, 240 (unsigned long long)c->nr_running, 241 (unsigned long long)c->nr_stopped, 242 (unsigned long long)c->nr_uninterruptible); 243 } 244 245 246 static void print_ioacct(struct taskstats *t) 247 { 248 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n", 249 t->ac_comm, 250 (unsigned long long)t->read_bytes, 251 (unsigned long long)t->write_bytes, 252 (unsigned long long)t->cancelled_write_bytes); 253 } 254 255 int main(int argc, char *argv[]) 256 { 257 int c, rc, rep_len, aggr_len, len2; 258 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC; 259 __u16 id; 260 __u32 mypid; 261 262 struct nlattr *na; 263 int nl_sd = -1; 264 int len = 0; 265 pid_t tid = 0; 266 pid_t rtid = 0; 267 268 int fd = 0; 269 int count = 0; 270 int write_file = 0; 271 int maskset = 0; 272 char *logfile = NULL; 273 int loop = 0; 274 int containerset = 0; 275 char *containerpath = NULL; 276 int cfd = 0; 277 int forking = 0; 278 sigset_t sigset; 279 280 struct msgtemplate msg; 281 282 while (!forking) { 283 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:"); 284 if (c < 0) 285 break; 286 287 switch (c) { 288 case 'd': 289 printf("print delayacct stats ON\n"); 290 print_delays = 1; 291 break; 292 case 'i': 293 printf("printing IO accounting\n"); 294 print_io_accounting = 1; 295 break; 296 case 'q': 297 printf("printing task/process context switch rates\n"); 298 print_task_context_switch_counts = 1; 299 break; 300 case 'C': 301 containerset = 1; 302 containerpath = optarg; 303 break; 304 case 'w': 305 logfile = strdup(optarg); 306 printf("write to file %s\n", logfile); 307 write_file = 1; 308 break; 309 case 'r': 310 rcvbufsz = atoi(optarg); 311 printf("receive buf size %d\n", rcvbufsz); 312 if (rcvbufsz < 0) 313 err(1, "Invalid rcv buf size\n"); 314 break; 315 case 'm': 316 strncpy(cpumask, optarg, sizeof(cpumask)); 317 cpumask[sizeof(cpumask) - 1] = '\0'; 318 maskset = 1; 319 printf("cpumask %s maskset %d\n", cpumask, maskset); 320 break; 321 case 't': 322 tid = atoi(optarg); 323 if (!tid) 324 err(1, "Invalid tgid\n"); 325 cmd_type = TASKSTATS_CMD_ATTR_TGID; 326 break; 327 case 'p': 328 tid = atoi(optarg); 329 if (!tid) 330 err(1, "Invalid pid\n"); 331 cmd_type = TASKSTATS_CMD_ATTR_PID; 332 break; 333 case 'c': 334 335 /* Block SIGCHLD for sigwait() later */ 336 if (sigemptyset(&sigset) == -1) 337 err(1, "Failed to empty sigset"); 338 if (sigaddset(&sigset, SIGCHLD)) 339 err(1, "Failed to set sigchld in sigset"); 340 sigprocmask(SIG_BLOCK, &sigset, NULL); 341 342 /* fork/exec a child */ 343 tid = fork(); 344 if (tid < 0) 345 err(1, "Fork failed\n"); 346 if (tid == 0) 347 if (execvp(argv[optind - 1], 348 &argv[optind - 1]) < 0) 349 exit(-1); 350 351 /* Set the command type and avoid further processing */ 352 cmd_type = TASKSTATS_CMD_ATTR_PID; 353 forking = 1; 354 break; 355 case 'v': 356 printf("debug on\n"); 357 dbg = 1; 358 break; 359 case 'l': 360 printf("listen forever\n"); 361 loop = 1; 362 break; 363 default: 364 usage(); 365 exit(-1); 366 } 367 } 368 369 if (write_file) { 370 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, 371 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 372 if (fd == -1) { 373 perror("Cannot open output file\n"); 374 exit(1); 375 } 376 } 377 378 nl_sd = create_nl_socket(NETLINK_GENERIC); 379 if (nl_sd < 0) 380 err(1, "error creating Netlink socket\n"); 381 382 383 mypid = getpid(); 384 id = get_family_id(nl_sd); 385 if (!id) { 386 fprintf(stderr, "Error getting family id, errno %d\n", errno); 387 goto err; 388 } 389 PRINTF("family id %d\n", id); 390 391 if (maskset) { 392 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 393 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK, 394 &cpumask, strlen(cpumask) + 1); 395 PRINTF("Sent register cpumask, retval %d\n", rc); 396 if (rc < 0) { 397 fprintf(stderr, "error sending register cpumask\n"); 398 goto err; 399 } 400 } 401 402 if (tid && containerset) { 403 fprintf(stderr, "Select either -t or -C, not both\n"); 404 goto err; 405 } 406 407 /* 408 * If we forked a child, wait for it to exit. Cannot use waitpid() 409 * as all the delicious data would be reaped as part of the wait 410 */ 411 if (tid && forking) { 412 int sig_received; 413 sigwait(&sigset, &sig_received); 414 } 415 416 if (tid) { 417 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 418 cmd_type, &tid, sizeof(__u32)); 419 PRINTF("Sent pid/tgid, retval %d\n", rc); 420 if (rc < 0) { 421 fprintf(stderr, "error sending tid/tgid cmd\n"); 422 goto done; 423 } 424 } 425 426 if (containerset) { 427 cfd = open(containerpath, O_RDONLY); 428 if (cfd < 0) { 429 perror("error opening container file"); 430 goto err; 431 } 432 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET, 433 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32)); 434 if (rc < 0) { 435 perror("error sending cgroupstats command"); 436 goto err; 437 } 438 } 439 if (!maskset && !tid && !containerset) { 440 usage(); 441 goto err; 442 } 443 444 do { 445 rep_len = recv(nl_sd, &msg, sizeof(msg), 0); 446 PRINTF("received %d bytes\n", rep_len); 447 448 if (rep_len < 0) { 449 fprintf(stderr, "nonfatal reply error: errno %d\n", 450 errno); 451 continue; 452 } 453 if (msg.n.nlmsg_type == NLMSG_ERROR || 454 !NLMSG_OK((&msg.n), rep_len)) { 455 struct nlmsgerr *err = NLMSG_DATA(&msg); 456 fprintf(stderr, "fatal reply error, errno %d\n", 457 err->error); 458 goto done; 459 } 460 461 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n", 462 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len); 463 464 465 rep_len = GENLMSG_PAYLOAD(&msg.n); 466 467 na = (struct nlattr *) GENLMSG_DATA(&msg); 468 len = 0; 469 while (len < rep_len) { 470 len += NLA_ALIGN(na->nla_len); 471 switch (na->nla_type) { 472 case TASKSTATS_TYPE_AGGR_TGID: 473 /* Fall through */ 474 case TASKSTATS_TYPE_AGGR_PID: 475 aggr_len = NLA_PAYLOAD(na->nla_len); 476 len2 = 0; 477 /* For nested attributes, na follows */ 478 na = (struct nlattr *) NLA_DATA(na); 479 done = 0; 480 while (len2 < aggr_len) { 481 switch (na->nla_type) { 482 case TASKSTATS_TYPE_PID: 483 rtid = *(int *) NLA_DATA(na); 484 if (print_delays) 485 printf("PID\t%d\n", rtid); 486 break; 487 case TASKSTATS_TYPE_TGID: 488 rtid = *(int *) NLA_DATA(na); 489 if (print_delays) 490 printf("TGID\t%d\n", rtid); 491 break; 492 case TASKSTATS_TYPE_STATS: 493 count++; 494 if (print_delays) 495 print_delayacct((struct taskstats *) NLA_DATA(na)); 496 if (print_io_accounting) 497 print_ioacct((struct taskstats *) NLA_DATA(na)); 498 if (print_task_context_switch_counts) 499 task_context_switch_counts((struct taskstats *) NLA_DATA(na)); 500 if (fd) { 501 if (write(fd, NLA_DATA(na), na->nla_len) < 0) { 502 err(1,"write error\n"); 503 } 504 } 505 if (!loop) 506 goto done; 507 break; 508 case TASKSTATS_TYPE_NULL: 509 break; 510 default: 511 fprintf(stderr, "Unknown nested" 512 " nla_type %d\n", 513 na->nla_type); 514 break; 515 } 516 len2 += NLA_ALIGN(na->nla_len); 517 na = (struct nlattr *)((char *)na + 518 NLA_ALIGN(na->nla_len)); 519 } 520 break; 521 522 case CGROUPSTATS_TYPE_CGROUP_STATS: 523 print_cgroupstats(NLA_DATA(na)); 524 break; 525 default: 526 fprintf(stderr, "Unknown nla_type %d\n", 527 na->nla_type); 528 case TASKSTATS_TYPE_NULL: 529 break; 530 } 531 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len); 532 } 533 } while (loop); 534 done: 535 if (maskset) { 536 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 537 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK, 538 &cpumask, strlen(cpumask) + 1); 539 printf("Sent deregister mask, retval %d\n", rc); 540 if (rc < 0) 541 err(rc, "error sending deregister cpumask\n"); 542 } 543 err: 544 close(nl_sd); 545 if (fd) 546 close(fd); 547 if (cfd) 548 close(cfd); 549 return 0; 550 } 551