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 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 + 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 "THRASHING%12s%15s%15s\n" 207 " %15llu%15llu%15llums\n" 208 "COMPACT %12s%15s%15s\n" 209 " %15llu%15llu%15llums\n" 210 "WPCOPY %12s%15s%15s\n" 211 " %15llu%15llu%15llums\n", 212 "count", "real total", "virtual total", 213 "delay total", "delay average", 214 (unsigned long long)t->cpu_count, 215 (unsigned long long)t->cpu_run_real_total, 216 (unsigned long long)t->cpu_run_virtual_total, 217 (unsigned long long)t->cpu_delay_total, 218 average_ms((double)t->cpu_delay_total, t->cpu_count), 219 "count", "delay total", "delay average", 220 (unsigned long long)t->blkio_count, 221 (unsigned long long)t->blkio_delay_total, 222 average_ms(t->blkio_delay_total, t->blkio_count), 223 "count", "delay total", "delay average", 224 (unsigned long long)t->swapin_count, 225 (unsigned long long)t->swapin_delay_total, 226 average_ms(t->swapin_delay_total, t->swapin_count), 227 "count", "delay total", "delay average", 228 (unsigned long long)t->freepages_count, 229 (unsigned long long)t->freepages_delay_total, 230 average_ms(t->freepages_delay_total, t->freepages_count), 231 "count", "delay total", "delay average", 232 (unsigned long long)t->thrashing_count, 233 (unsigned long long)t->thrashing_delay_total, 234 average_ms(t->thrashing_delay_total, t->thrashing_count), 235 "count", "delay total", "delay average", 236 (unsigned long long)t->compact_count, 237 (unsigned long long)t->compact_delay_total, 238 average_ms(t->compact_delay_total, t->compact_count), 239 "count", "delay total", "delay average", 240 (unsigned long long)t->wpcopy_count, 241 (unsigned long long)t->wpcopy_delay_total, 242 average_ms(t->wpcopy_delay_total, t->wpcopy_count)); 243 } 244 245 static void task_context_switch_counts(struct taskstats *t) 246 { 247 printf("\n\nTask %15s%15s\n" 248 " %15llu%15llu\n", 249 "voluntary", "nonvoluntary", 250 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw); 251 } 252 253 static void print_cgroupstats(struct cgroupstats *c) 254 { 255 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, " 256 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping, 257 (unsigned long long)c->nr_io_wait, 258 (unsigned long long)c->nr_running, 259 (unsigned long long)c->nr_stopped, 260 (unsigned long long)c->nr_uninterruptible); 261 } 262 263 264 static void print_ioacct(struct taskstats *t) 265 { 266 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n", 267 t->ac_comm, 268 (unsigned long long)t->read_bytes, 269 (unsigned long long)t->write_bytes, 270 (unsigned long long)t->cancelled_write_bytes); 271 } 272 273 int main(int argc, char *argv[]) 274 { 275 int c, rc, rep_len, aggr_len, len2; 276 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC; 277 __u16 id; 278 __u32 mypid; 279 280 struct nlattr *na; 281 int nl_sd = -1; 282 int len = 0; 283 pid_t tid = 0; 284 pid_t rtid = 0; 285 286 int fd = 0; 287 int write_file = 0; 288 int maskset = 0; 289 char *logfile = NULL; 290 int loop = 0; 291 int containerset = 0; 292 char *containerpath = NULL; 293 int cfd = 0; 294 int forking = 0; 295 sigset_t sigset; 296 297 struct msgtemplate msg; 298 299 while (!forking) { 300 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:"); 301 if (c < 0) 302 break; 303 304 switch (c) { 305 case 'd': 306 printf("print delayacct stats ON\n"); 307 print_delays = 1; 308 break; 309 case 'i': 310 printf("printing IO accounting\n"); 311 print_io_accounting = 1; 312 break; 313 case 'q': 314 printf("printing task/process context switch rates\n"); 315 print_task_context_switch_counts = 1; 316 break; 317 case 'C': 318 containerset = 1; 319 containerpath = optarg; 320 break; 321 case 'w': 322 logfile = strdup(optarg); 323 printf("write to file %s\n", logfile); 324 write_file = 1; 325 break; 326 case 'r': 327 rcvbufsz = atoi(optarg); 328 printf("receive buf size %d\n", rcvbufsz); 329 if (rcvbufsz < 0) 330 err(1, "Invalid rcv buf size\n"); 331 break; 332 case 'm': 333 strncpy(cpumask, optarg, sizeof(cpumask)); 334 cpumask[sizeof(cpumask) - 1] = '\0'; 335 maskset = 1; 336 printf("cpumask %s maskset %d\n", cpumask, maskset); 337 break; 338 case 't': 339 tid = atoi(optarg); 340 if (!tid) 341 err(1, "Invalid tgid\n"); 342 cmd_type = TASKSTATS_CMD_ATTR_TGID; 343 break; 344 case 'p': 345 tid = atoi(optarg); 346 if (!tid) 347 err(1, "Invalid pid\n"); 348 cmd_type = TASKSTATS_CMD_ATTR_PID; 349 break; 350 case 'c': 351 352 /* Block SIGCHLD for sigwait() later */ 353 if (sigemptyset(&sigset) == -1) 354 err(1, "Failed to empty sigset"); 355 if (sigaddset(&sigset, SIGCHLD)) 356 err(1, "Failed to set sigchld in sigset"); 357 sigprocmask(SIG_BLOCK, &sigset, NULL); 358 359 /* fork/exec a child */ 360 tid = fork(); 361 if (tid < 0) 362 err(1, "Fork failed\n"); 363 if (tid == 0) 364 if (execvp(argv[optind - 1], 365 &argv[optind - 1]) < 0) 366 exit(-1); 367 368 /* Set the command type and avoid further processing */ 369 cmd_type = TASKSTATS_CMD_ATTR_PID; 370 forking = 1; 371 break; 372 case 'v': 373 printf("debug on\n"); 374 dbg = 1; 375 break; 376 case 'l': 377 printf("listen forever\n"); 378 loop = 1; 379 break; 380 default: 381 usage(); 382 exit(-1); 383 } 384 } 385 386 if (write_file) { 387 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, 388 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 389 if (fd == -1) { 390 perror("Cannot open output file\n"); 391 exit(1); 392 } 393 } 394 395 nl_sd = create_nl_socket(NETLINK_GENERIC); 396 if (nl_sd < 0) 397 err(1, "error creating Netlink socket\n"); 398 399 400 mypid = getpid(); 401 id = get_family_id(nl_sd); 402 if (!id) { 403 fprintf(stderr, "Error getting family id, errno %d\n", errno); 404 goto err; 405 } 406 PRINTF("family id %d\n", id); 407 408 if (maskset) { 409 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 410 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK, 411 &cpumask, strlen(cpumask) + 1); 412 PRINTF("Sent register cpumask, retval %d\n", rc); 413 if (rc < 0) { 414 fprintf(stderr, "error sending register cpumask\n"); 415 goto err; 416 } 417 } 418 419 if (tid && containerset) { 420 fprintf(stderr, "Select either -t or -C, not both\n"); 421 goto err; 422 } 423 424 /* 425 * If we forked a child, wait for it to exit. Cannot use waitpid() 426 * as all the delicious data would be reaped as part of the wait 427 */ 428 if (tid && forking) { 429 int sig_received; 430 sigwait(&sigset, &sig_received); 431 } 432 433 if (tid) { 434 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 435 cmd_type, &tid, sizeof(__u32)); 436 PRINTF("Sent pid/tgid, retval %d\n", rc); 437 if (rc < 0) { 438 fprintf(stderr, "error sending tid/tgid cmd\n"); 439 goto done; 440 } 441 } 442 443 if (containerset) { 444 cfd = open(containerpath, O_RDONLY); 445 if (cfd < 0) { 446 perror("error opening container file"); 447 goto err; 448 } 449 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET, 450 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32)); 451 if (rc < 0) { 452 perror("error sending cgroupstats command"); 453 goto err; 454 } 455 } 456 if (!maskset && !tid && !containerset) { 457 usage(); 458 goto err; 459 } 460 461 do { 462 rep_len = recv(nl_sd, &msg, sizeof(msg), 0); 463 PRINTF("received %d bytes\n", rep_len); 464 465 if (rep_len < 0) { 466 fprintf(stderr, "nonfatal reply error: errno %d\n", 467 errno); 468 continue; 469 } 470 if (msg.n.nlmsg_type == NLMSG_ERROR || 471 !NLMSG_OK((&msg.n), rep_len)) { 472 struct nlmsgerr *err = NLMSG_DATA(&msg); 473 fprintf(stderr, "fatal reply error, errno %d\n", 474 err->error); 475 goto done; 476 } 477 478 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n", 479 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len); 480 481 482 rep_len = GENLMSG_PAYLOAD(&msg.n); 483 484 na = (struct nlattr *) GENLMSG_DATA(&msg); 485 len = 0; 486 while (len < rep_len) { 487 len += NLA_ALIGN(na->nla_len); 488 switch (na->nla_type) { 489 case TASKSTATS_TYPE_AGGR_TGID: 490 /* Fall through */ 491 case TASKSTATS_TYPE_AGGR_PID: 492 aggr_len = NLA_PAYLOAD(na->nla_len); 493 len2 = 0; 494 /* For nested attributes, na follows */ 495 na = (struct nlattr *) NLA_DATA(na); 496 while (len2 < aggr_len) { 497 switch (na->nla_type) { 498 case TASKSTATS_TYPE_PID: 499 rtid = *(int *) NLA_DATA(na); 500 if (print_delays) 501 printf("PID\t%d\n", rtid); 502 break; 503 case TASKSTATS_TYPE_TGID: 504 rtid = *(int *) NLA_DATA(na); 505 if (print_delays) 506 printf("TGID\t%d\n", rtid); 507 break; 508 case TASKSTATS_TYPE_STATS: 509 if (print_delays) 510 print_delayacct((struct taskstats *) NLA_DATA(na)); 511 if (print_io_accounting) 512 print_ioacct((struct taskstats *) NLA_DATA(na)); 513 if (print_task_context_switch_counts) 514 task_context_switch_counts((struct taskstats *) NLA_DATA(na)); 515 if (fd) { 516 if (write(fd, NLA_DATA(na), na->nla_len) < 0) { 517 err(1,"write error\n"); 518 } 519 } 520 if (!loop) 521 goto done; 522 break; 523 case TASKSTATS_TYPE_NULL: 524 break; 525 default: 526 fprintf(stderr, "Unknown nested" 527 " nla_type %d\n", 528 na->nla_type); 529 break; 530 } 531 len2 += NLA_ALIGN(na->nla_len); 532 na = (struct nlattr *)((char *)na + 533 NLA_ALIGN(na->nla_len)); 534 } 535 break; 536 537 case CGROUPSTATS_TYPE_CGROUP_STATS: 538 print_cgroupstats(NLA_DATA(na)); 539 break; 540 default: 541 fprintf(stderr, "Unknown nla_type %d\n", 542 na->nla_type); 543 case TASKSTATS_TYPE_NULL: 544 break; 545 } 546 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len); 547 } 548 } while (loop); 549 done: 550 if (maskset) { 551 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET, 552 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK, 553 &cpumask, strlen(cpumask) + 1); 554 printf("Sent deregister mask, retval %d\n", rc); 555 if (rc < 0) 556 err(rc, "error sending deregister cpumask\n"); 557 } 558 err: 559 close(nl_sd); 560 if (fd) 561 close(fd); 562 if (cfd) 563 close(cfd); 564 return 0; 565 } 566