1 // SPDX-License-Identifier: GPL-2.0 2 /* getdelays.c 3 * 4 * Utility to get per-pid and per-tgid delay accounting statistics 5 * Also illustrates usage of the taskstats interface 6 * 7 * Copyright (C) Shailabh Nagar, IBM Corp. 2005 8 * Copyright (C) Balbir Singh, IBM Corp. 2006 9 * Copyright (c) Jay Lan, SGI. 2006 10 * 11 * Compile with 12 * gcc -I/usr/src/linux/include getdelays.c -o getdelays 13 */ 14 15 #include <stdio.h> 16 #include <stdlib.h> 17 #include <errno.h> 18 #include <unistd.h> 19 #include <poll.h> 20 #include <string.h> 21 #include <fcntl.h> 22 #include <sys/types.h> 23 #include <sys/stat.h> 24 #include <sys/socket.h> 25 #include <sys/wait.h> 26 #include <signal.h> 27 28 #include <linux/genetlink.h> 29 #include <linux/taskstats.h> 30 #include <linux/cgroupstats.h> 31 32 /* 33 * Generic macros for dealing with netlink sockets. Might be duplicated 34 * elsewhere. It is recommended that commercial grade applications use 35 * libnl or libnetlink and use the interfaces provided by the library 36 */ 37 #define GENLMSG_DATA(glh) ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN)) 38 #define GENLMSG_PAYLOAD(glh) (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN) 39 #define NLA_DATA(na) ((void *)((char*)(na) + NLA_HDRLEN)) 40 #define NLA_PAYLOAD(len) (len - NLA_HDRLEN) 41 42 #define err(code, fmt, arg...) \ 43 do { \ 44 fprintf(stderr, fmt, ##arg); \ 45 exit(code); \ 46 } while (0) 47 48 int done; 49 int rcvbufsz; 50 char name[100]; 51 int dbg; 52 int print_delays; 53 int print_io_accounting; 54 int print_task_context_switch_counts; 55 56 #define PRINTF(fmt, arg...) { \ 57 if (dbg) { \ 58 printf(fmt, ##arg); \ 59 } \ 60 } 61 62 /* Maximum size of response requested or message sent */ 63 #define MAX_MSG_SIZE 1024 64 /* Maximum number of cpus expected to be specified in a cpumask */ 65 #define MAX_CPUS 32 66 67 struct msgtemplate { 68 struct nlmsghdr n; 69 struct genlmsghdr g; 70 char buf[MAX_MSG_SIZE]; 71 }; 72 73 char cpumask[100+6*MAX_CPUS]; 74 75 static void usage(void) 76 { 77 fprintf(stderr, "getdelays [-dilv] [-w logfile] [-r bufsize] " 78 "[-m cpumask] [-t tgid] [-p pid]\n"); 79 fprintf(stderr, " -d: print delayacct stats\n"); 80 fprintf(stderr, " -i: print IO accounting (works only with -p)\n"); 81 fprintf(stderr, " -l: listen forever\n"); 82 fprintf(stderr, " -v: debug on\n"); 83 fprintf(stderr, " -C: container path\n"); 84 } 85 86 /* 87 * Create a raw netlink socket and bind 88 */ 89 static int create_nl_socket(int protocol) 90 { 91 int fd; 92 struct sockaddr_nl local; 93 94 fd = socket(AF_NETLINK, SOCK_RAW, protocol); 95 if (fd < 0) 96 return -1; 97 98 if (rcvbufsz) 99 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, 100 &rcvbufsz, sizeof(rcvbufsz)) < 0) { 101 fprintf(stderr, "Unable to set socket rcv buf size to %d\n", 102 rcvbufsz); 103 goto error; 104 } 105 106 memset(&local, 0, sizeof(local)); 107 local.nl_family = AF_NETLINK; 108 109 if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0) 110 goto error; 111 112 return fd; 113 error: 114 close(fd); 115 return -1; 116 } 117 118 119 static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid, 120 __u8 genl_cmd, __u16 nla_type, 121 void *nla_data, int nla_len) 122 { 123 struct nlattr *na; 124 struct sockaddr_nl nladdr; 125 int r, buflen; 126 char *buf; 127 128 struct msgtemplate msg; 129 130 msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN); 131 msg.n.nlmsg_type = nlmsg_type; 132 msg.n.nlmsg_flags = NLM_F_REQUEST; 133 msg.n.nlmsg_seq = 0; 134 msg.n.nlmsg_pid = nlmsg_pid; 135 msg.g.cmd = genl_cmd; 136 msg.g.version = 0x1; 137 na = (struct nlattr *) GENLMSG_DATA(&msg); 138 na->nla_type = nla_type; 139 na->nla_len = nla_len + NLA_HDRLEN; 140 memcpy(NLA_DATA(na), nla_data, nla_len); 141 msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len); 142 143 buf = (char *) &msg; 144 buflen = msg.n.nlmsg_len ; 145 memset(&nladdr, 0, sizeof(nladdr)); 146 nladdr.nl_family = AF_NETLINK; 147 while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr, 148 sizeof(nladdr))) < buflen) { 149 if (r > 0) { 150 buf += r; 151 buflen -= r; 152 } else if (errno != EAGAIN) 153 return -1; 154 } 155 return 0; 156 } 157 158 159 /* 160 * Probe the controller in genetlink to find the family id 161 * for the TASKSTATS family 162 */ 163 static int get_family_id(int sd) 164 { 165 struct { 166 struct nlmsghdr n; 167 struct genlmsghdr g; 168 char buf[256]; 169 } ans; 170 171 int id = 0, rc; 172 struct nlattr *na; 173 int rep_len; 174 175 strcpy(name, TASKSTATS_GENL_NAME); 176 rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY, 177 CTRL_ATTR_FAMILY_NAME, (void *)name, 178 strlen(TASKSTATS_GENL_NAME)+1); 179 if (rc < 0) 180 return 0; /* sendto() failure? */ 181 182 rep_len = recv(sd, &ans, sizeof(ans), 0); 183 if (ans.n.nlmsg_type == NLMSG_ERROR || 184 (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len)) 185 return 0; 186 187 na = (struct nlattr *) GENLMSG_DATA(&ans); 188 na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len)); 189 if (na->nla_type == CTRL_ATTR_FAMILY_ID) { 190 id = *(__u16 *) NLA_DATA(na); 191 } 192 return id; 193 } 194 195 #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1)) 196 197 static void print_delayacct(struct taskstats *t) 198 { 199 printf("\n\nCPU %15s%15s%15s%15s%15s\n" 200 " %15llu%15llu%15llu%15llu%15.3fms\n" 201 "IO %15s%15s%15s\n" 202 " %15llu%15llu%15llums\n" 203 "SWAP %15s%15s%15s\n" 204 " %15llu%15llu%15llums\n" 205 "RECLAIM %12s%15s%15s\n" 206 " %15llu%15llu%15llums\n" 207 "THRASHING%12s%15s%15s\n" 208 " %15llu%15llu%15llums\n", 209 "count", "real total", "virtual total", 210 "delay total", "delay average", 211 (unsigned long long)t->cpu_count, 212 (unsigned long long)t->cpu_run_real_total, 213 (unsigned long long)t->cpu_run_virtual_total, 214 (unsigned long long)t->cpu_delay_total, 215 average_ms((double)t->cpu_delay_total, t->cpu_count), 216 "count", "delay total", "delay average", 217 (unsigned long long)t->blkio_count, 218 (unsigned long long)t->blkio_delay_total, 219 average_ms(t->blkio_delay_total, t->blkio_count), 220 "count", "delay total", "delay average", 221 (unsigned long long)t->swapin_count, 222 (unsigned long long)t->swapin_delay_total, 223 average_ms(t->swapin_delay_total, t->swapin_count), 224 "count", "delay total", "delay average", 225 (unsigned long long)t->freepages_count, 226 (unsigned long long)t->freepages_delay_total, 227 average_ms(t->freepages_delay_total, t->freepages_count), 228 "count", "delay total", "delay average", 229 (unsigned long long)t->thrashing_count, 230 (unsigned long long)t->thrashing_delay_total, 231 average_ms(t->thrashing_delay_total, t->thrashing_count)); 232 } 233 234 static void task_context_switch_counts(struct taskstats *t) 235 { 236 printf("\n\nTask %15s%15s\n" 237 " %15llu%15llu\n", 238 "voluntary", "nonvoluntary", 239 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw); 240 } 241 242 static void print_cgroupstats(struct cgroupstats *c) 243 { 244 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, " 245 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping, 246 (unsigned long long)c->nr_io_wait, 247 (unsigned long long)c->nr_running, 248 (unsigned long long)c->nr_stopped, 249 (unsigned long long)c->nr_uninterruptible); 250 } 251 252 253 static void print_ioacct(struct taskstats *t) 254 { 255 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n", 256 t->ac_comm, 257 (unsigned long long)t->read_bytes, 258 (unsigned long long)t->write_bytes, 259 (unsigned long long)t->cancelled_write_bytes); 260 } 261 262 int main(int argc, char *argv[]) 263 { 264 int c, rc, rep_len, aggr_len, len2; 265 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC; 266 __u16 id; 267 __u32 mypid; 268 269 struct nlattr *na; 270 int nl_sd = -1; 271 int len = 0; 272 pid_t tid = 0; 273 pid_t rtid = 0; 274 275 int fd = 0; 276 int count = 0; 277 int write_file = 0; 278 int maskset = 0; 279 char *logfile = NULL; 280 int loop = 0; 281 int containerset = 0; 282 char *containerpath = NULL; 283 int cfd = 0; 284 int forking = 0; 285 sigset_t sigset; 286 287 struct msgtemplate msg; 288 289 while (!forking) { 290 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:"); 291 if (c < 0) 292 break; 293 294 switch (c) { 295 case 'd': 296 printf("print delayacct stats ON\n"); 297 print_delays = 1; 298 break; 299 case 'i': 300 printf("printing IO accounting\n"); 301 print_io_accounting = 1; 302 break; 303 case 'q': 304 printf("printing task/process context switch rates\n"); 305 print_task_context_switch_counts = 1; 306 break; 307 case 'C': 308 containerset = 1; 309 containerpath = optarg; 310 break; 311 case 'w': 312 logfile = strdup(optarg); 313 printf("write to file %s\n", logfile); 314 write_file = 1; 315 break; 316 case 'r': 317 rcvbufsz = atoi(optarg); 318 printf("receive buf size %d\n", rcvbufsz); 319 if (rcvbufsz < 0) 320 err(1, "Invalid rcv buf size\n"); 321 break; 322 case 'm': 323 strncpy(cpumask, optarg, sizeof(cpumask)); 324 cpumask[sizeof(cpumask) - 1] = '\0'; 325 maskset = 1; 326 printf("cpumask %s maskset %d\n", cpumask, maskset); 327 break; 328 case 't': 329 tid = atoi(optarg); 330 if (!tid) 331 err(1, "Invalid tgid\n"); 332 cmd_type = TASKSTATS_CMD_ATTR_TGID; 333 break; 334 case 'p': 335 tid = atoi(optarg); 336 if (!tid) 337 err(1, "Invalid pid\n"); 338 cmd_type = TASKSTATS_CMD_ATTR_PID; 339 break; 340 case 'c': 341 342 /* Block SIGCHLD for sigwait() later */ 343 if (sigemptyset(&sigset) == -1) 344 err(1, "Failed to empty sigset"); 345 if (sigaddset(&sigset, SIGCHLD)) 346 err(1, "Failed to set sigchld in sigset"); 347 sigprocmask(SIG_BLOCK, &sigset, NULL); 348 349 /* fork/exec a child */ 350 tid = fork(); 351 if (tid < 0) 352 err(1, "Fork failed\n"); 353 if (tid == 0) 354 if (execvp(argv[optind - 1], 355 &argv[optind - 1]) < 0) 356 exit(-1); 357 358 /* Set the command type and avoid further processing */ 359 cmd_type = TASKSTATS_CMD_ATTR_PID; 360 forking = 1; 361 break; 362 case 'v': 363 printf("debug on\n"); 364 dbg = 1; 365 break; 366 case 'l': 367 printf("listen forever\n"); 368 loop = 1; 369 break; 370 default: 371 usage(); 372 exit(-1); 373 } 374 } 375 376 if (write_file) { 377 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, 378 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 379 if (fd == -1) { 380 perror("Cannot open output file\n"); 381 exit(1); 382 } 383 } 384 385 nl_sd = create_nl_socket(NETLINK_GENERIC); 386 if (nl_sd < 0) 387 err(1, "error creating Netlink socket\n"); 388 389 390 mypid = getpid(); 391 id = get_family_id(nl_sd); 392 if (!id) { 393 fprintf(stderr, "Error getting family id, errno %d\n", errno); 394 goto err; 395 } 396 PRINTF("family id %d\n", id); 397 398 if (maskset) { 399 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 400 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK, 401 &cpumask, strlen(cpumask) + 1); 402 PRINTF("Sent register cpumask, retval %d\n", rc); 403 if (rc < 0) { 404 fprintf(stderr, "error sending register cpumask\n"); 405 goto err; 406 } 407 } 408 409 if (tid && containerset) { 410 fprintf(stderr, "Select either -t or -C, not both\n"); 411 goto err; 412 } 413 414 /* 415 * If we forked a child, wait for it to exit. Cannot use waitpid() 416 * as all the delicious data would be reaped as part of the wait 417 */ 418 if (tid && forking) { 419 int sig_received; 420 sigwait(&sigset, &sig_received); 421 } 422 423 if (tid) { 424 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 425 cmd_type, &tid, sizeof(__u32)); 426 PRINTF("Sent pid/tgid, retval %d\n", rc); 427 if (rc < 0) { 428 fprintf(stderr, "error sending tid/tgid cmd\n"); 429 goto done; 430 } 431 } 432 433 if (containerset) { 434 cfd = open(containerpath, O_RDONLY); 435 if (cfd < 0) { 436 perror("error opening container file"); 437 goto err; 438 } 439 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET, 440 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32)); 441 if (rc < 0) { 442 perror("error sending cgroupstats command"); 443 goto err; 444 } 445 } 446 if (!maskset && !tid && !containerset) { 447 usage(); 448 goto err; 449 } 450 451 do { 452 rep_len = recv(nl_sd, &msg, sizeof(msg), 0); 453 PRINTF("received %d bytes\n", rep_len); 454 455 if (rep_len < 0) { 456 fprintf(stderr, "nonfatal reply error: errno %d\n", 457 errno); 458 continue; 459 } 460 if (msg.n.nlmsg_type == NLMSG_ERROR || 461 !NLMSG_OK((&msg.n), rep_len)) { 462 struct nlmsgerr *err = NLMSG_DATA(&msg); 463 fprintf(stderr, "fatal reply error, errno %d\n", 464 err->error); 465 goto done; 466 } 467 468 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n", 469 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len); 470 471 472 rep_len = GENLMSG_PAYLOAD(&msg.n); 473 474 na = (struct nlattr *) GENLMSG_DATA(&msg); 475 len = 0; 476 while (len < rep_len) { 477 len += NLA_ALIGN(na->nla_len); 478 switch (na->nla_type) { 479 case TASKSTATS_TYPE_AGGR_TGID: 480 /* Fall through */ 481 case TASKSTATS_TYPE_AGGR_PID: 482 aggr_len = NLA_PAYLOAD(na->nla_len); 483 len2 = 0; 484 /* For nested attributes, na follows */ 485 na = (struct nlattr *) NLA_DATA(na); 486 done = 0; 487 while (len2 < aggr_len) { 488 switch (na->nla_type) { 489 case TASKSTATS_TYPE_PID: 490 rtid = *(int *) NLA_DATA(na); 491 if (print_delays) 492 printf("PID\t%d\n", rtid); 493 break; 494 case TASKSTATS_TYPE_TGID: 495 rtid = *(int *) NLA_DATA(na); 496 if (print_delays) 497 printf("TGID\t%d\n", rtid); 498 break; 499 case TASKSTATS_TYPE_STATS: 500 count++; 501 if (print_delays) 502 print_delayacct((struct taskstats *) NLA_DATA(na)); 503 if (print_io_accounting) 504 print_ioacct((struct taskstats *) NLA_DATA(na)); 505 if (print_task_context_switch_counts) 506 task_context_switch_counts((struct taskstats *) NLA_DATA(na)); 507 if (fd) { 508 if (write(fd, NLA_DATA(na), na->nla_len) < 0) { 509 err(1,"write error\n"); 510 } 511 } 512 if (!loop) 513 goto done; 514 break; 515 case TASKSTATS_TYPE_NULL: 516 break; 517 default: 518 fprintf(stderr, "Unknown nested" 519 " nla_type %d\n", 520 na->nla_type); 521 break; 522 } 523 len2 += NLA_ALIGN(na->nla_len); 524 na = (struct nlattr *)((char *)na + 525 NLA_ALIGN(na->nla_len)); 526 } 527 break; 528 529 case CGROUPSTATS_TYPE_CGROUP_STATS: 530 print_cgroupstats(NLA_DATA(na)); 531 break; 532 default: 533 fprintf(stderr, "Unknown nla_type %d\n", 534 na->nla_type); 535 case TASKSTATS_TYPE_NULL: 536 break; 537 } 538 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len); 539 } 540 } while (loop); 541 done: 542 if (maskset) { 543 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 544 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK, 545 &cpumask, strlen(cpumask) + 1); 546 printf("Sent deregister mask, retval %d\n", rc); 547 if (rc < 0) 548 err(rc, "error sending deregister cpumask\n"); 549 } 550 err: 551 close(nl_sd); 552 if (fd) 553 close(fd); 554 if (cfd) 555 close(cfd); 556 return 0; 557 } 558