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1// SPDX-License-Identifier: GPL-2.02/* getdelays.c3 *4 * Utility to get per-pid and per-tgid delay accounting statistics5 * Also illustrates usage of the taskstats interface6 *7 * Copyright (C) Shailabh Nagar, IBM Corp. 20058 * Copyright (C) Balbir Singh, IBM Corp. 20069 * Copyright (c) Jay Lan, SGI. 200610 *11 * Compile with12 * gcc -I/usr/src/linux/include getdelays.c -o getdelays13 */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 duplicated34 * elsewhere. It is recommended that commercial grade applications use35 * libnl or libnetlink and use the interfaces provided by the library36 */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 48int rcvbufsz;49char name[100];50int dbg;51int print_delays;52int print_io_accounting;53int 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 102463/* Maximum number of cpus expected to be specified in a cpumask */64#define MAX_CPUS 3265 66struct msgtemplate {67 struct nlmsghdr n;68 struct genlmsghdr g;69 char buf[MAX_MSG_SIZE];70};71 72char cpumask[100+6*MAX_CPUS];73 74static 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 bind87 */88static 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;112error:113 close(fd);114 return -1;115}116 117 118static 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 id160 * for the TASKSTATS family161 */162static 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 196static 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%15.3fms\n"202 "SWAP %15s%15s%15s\n"203 " %15llu%15llu%15.3fms\n"204 "RECLAIM %12s%15s%15s\n"205 " %15llu%15llu%15.3fms\n"206 "THRASHING%12s%15s%15s\n"207 " %15llu%15llu%15.3fms\n"208 "COMPACT %12s%15s%15s\n"209 " %15llu%15llu%15.3fms\n"210 "WPCOPY %12s%15s%15s\n"211 " %15llu%15llu%15.3fms\n"212 "IRQ %15s%15s%15s\n"213 " %15llu%15llu%15.3fms\n",214 "count", "real total", "virtual total",215 "delay total", "delay average",216 (unsigned long long)t->cpu_count,217 (unsigned long long)t->cpu_run_real_total,218 (unsigned long long)t->cpu_run_virtual_total,219 (unsigned long long)t->cpu_delay_total,220 average_ms((double)t->cpu_delay_total, t->cpu_count),221 "count", "delay total", "delay average",222 (unsigned long long)t->blkio_count,223 (unsigned long long)t->blkio_delay_total,224 average_ms((double)t->blkio_delay_total, t->blkio_count),225 "count", "delay total", "delay average",226 (unsigned long long)t->swapin_count,227 (unsigned long long)t->swapin_delay_total,228 average_ms((double)t->swapin_delay_total, t->swapin_count),229 "count", "delay total", "delay average",230 (unsigned long long)t->freepages_count,231 (unsigned long long)t->freepages_delay_total,232 average_ms((double)t->freepages_delay_total, t->freepages_count),233 "count", "delay total", "delay average",234 (unsigned long long)t->thrashing_count,235 (unsigned long long)t->thrashing_delay_total,236 average_ms((double)t->thrashing_delay_total, t->thrashing_count),237 "count", "delay total", "delay average",238 (unsigned long long)t->compact_count,239 (unsigned long long)t->compact_delay_total,240 average_ms((double)t->compact_delay_total, t->compact_count),241 "count", "delay total", "delay average",242 (unsigned long long)t->wpcopy_count,243 (unsigned long long)t->wpcopy_delay_total,244 average_ms((double)t->wpcopy_delay_total, t->wpcopy_count),245 "count", "delay total", "delay average",246 (unsigned long long)t->irq_count,247 (unsigned long long)t->irq_delay_total,248 average_ms((double)t->irq_delay_total, t->irq_count));249}250 251static void task_context_switch_counts(struct taskstats *t)252{253 printf("\n\nTask %15s%15s\n"254 " %15llu%15llu\n",255 "voluntary", "nonvoluntary",256 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);257}258 259static void print_cgroupstats(struct cgroupstats *c)260{261 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, "262 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,263 (unsigned long long)c->nr_io_wait,264 (unsigned long long)c->nr_running,265 (unsigned long long)c->nr_stopped,266 (unsigned long long)c->nr_uninterruptible);267}268 269 270static void print_ioacct(struct taskstats *t)271{272 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",273 t->ac_comm,274 (unsigned long long)t->read_bytes,275 (unsigned long long)t->write_bytes,276 (unsigned long long)t->cancelled_write_bytes);277}278 279int main(int argc, char *argv[])280{281 int c, rc, rep_len, aggr_len, len2;282 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;283 __u16 id;284 __u32 mypid;285 286 struct nlattr *na;287 int nl_sd = -1;288 int len = 0;289 pid_t tid = 0;290 pid_t rtid = 0;291 292 int fd = 0;293 int write_file = 0;294 int maskset = 0;295 char *logfile = NULL;296 int loop = 0;297 int containerset = 0;298 char *containerpath = NULL;299 int cfd = 0;300 int forking = 0;301 sigset_t sigset;302 303 struct msgtemplate msg;304 305 while (!forking) {306 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");307 if (c < 0)308 break;309 310 switch (c) {311 case 'd':312 printf("print delayacct stats ON\n");313 print_delays = 1;314 break;315 case 'i':316 printf("printing IO accounting\n");317 print_io_accounting = 1;318 break;319 case 'q':320 printf("printing task/process context switch rates\n");321 print_task_context_switch_counts = 1;322 break;323 case 'C':324 containerset = 1;325 containerpath = optarg;326 break;327 case 'w':328 logfile = strdup(optarg);329 printf("write to file %s\n", logfile);330 write_file = 1;331 break;332 case 'r':333 rcvbufsz = atoi(optarg);334 printf("receive buf size %d\n", rcvbufsz);335 if (rcvbufsz < 0)336 err(1, "Invalid rcv buf size\n");337 break;338 case 'm':339 strncpy(cpumask, optarg, sizeof(cpumask));340 cpumask[sizeof(cpumask) - 1] = '\0';341 maskset = 1;342 printf("cpumask %s maskset %d\n", cpumask, maskset);343 break;344 case 't':345 tid = atoi(optarg);346 if (!tid)347 err(1, "Invalid tgid\n");348 cmd_type = TASKSTATS_CMD_ATTR_TGID;349 break;350 case 'p':351 tid = atoi(optarg);352 if (!tid)353 err(1, "Invalid pid\n");354 cmd_type = TASKSTATS_CMD_ATTR_PID;355 break;356 case 'c':357 358 /* Block SIGCHLD for sigwait() later */359 if (sigemptyset(&sigset) == -1)360 err(1, "Failed to empty sigset");361 if (sigaddset(&sigset, SIGCHLD))362 err(1, "Failed to set sigchld in sigset");363 sigprocmask(SIG_BLOCK, &sigset, NULL);364 365 /* fork/exec a child */366 tid = fork();367 if (tid < 0)368 err(1, "Fork failed\n");369 if (tid == 0)370 if (execvp(argv[optind - 1],371 &argv[optind - 1]) < 0)372 exit(-1);373 374 /* Set the command type and avoid further processing */375 cmd_type = TASKSTATS_CMD_ATTR_PID;376 forking = 1;377 break;378 case 'v':379 printf("debug on\n");380 dbg = 1;381 break;382 case 'l':383 printf("listen forever\n");384 loop = 1;385 break;386 default:387 usage();388 exit(-1);389 }390 }391 392 if (write_file) {393 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,394 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);395 if (fd == -1) {396 perror("Cannot open output file\n");397 exit(1);398 }399 }400 401 nl_sd = create_nl_socket(NETLINK_GENERIC);402 if (nl_sd < 0)403 err(1, "error creating Netlink socket\n");404 405 406 mypid = getpid();407 id = get_family_id(nl_sd);408 if (!id) {409 fprintf(stderr, "Error getting family id, errno %d\n", errno);410 goto err;411 }412 PRINTF("family id %d\n", id);413 414 if (maskset) {415 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,416 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,417 &cpumask, strlen(cpumask) + 1);418 PRINTF("Sent register cpumask, retval %d\n", rc);419 if (rc < 0) {420 fprintf(stderr, "error sending register cpumask\n");421 goto err;422 }423 }424 425 if (tid && containerset) {426 fprintf(stderr, "Select either -t or -C, not both\n");427 goto err;428 }429 430 /*431 * If we forked a child, wait for it to exit. Cannot use waitpid()432 * as all the delicious data would be reaped as part of the wait433 */434 if (tid && forking) {435 int sig_received;436 sigwait(&sigset, &sig_received);437 }438 439 if (tid) {440 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,441 cmd_type, &tid, sizeof(__u32));442 PRINTF("Sent pid/tgid, retval %d\n", rc);443 if (rc < 0) {444 fprintf(stderr, "error sending tid/tgid cmd\n");445 goto done;446 }447 }448 449 if (containerset) {450 cfd = open(containerpath, O_RDONLY);451 if (cfd < 0) {452 perror("error opening container file");453 goto err;454 }455 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,456 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));457 if (rc < 0) {458 perror("error sending cgroupstats command");459 goto err;460 }461 }462 if (!maskset && !tid && !containerset) {463 usage();464 goto err;465 }466 467 do {468 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);469 PRINTF("received %d bytes\n", rep_len);470 471 if (rep_len < 0) {472 fprintf(stderr, "nonfatal reply error: errno %d\n",473 errno);474 continue;475 }476 if (msg.n.nlmsg_type == NLMSG_ERROR ||477 !NLMSG_OK((&msg.n), rep_len)) {478 struct nlmsgerr *err = NLMSG_DATA(&msg);479 fprintf(stderr, "fatal reply error, errno %d\n",480 err->error);481 goto done;482 }483 484 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",485 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);486 487 488 rep_len = GENLMSG_PAYLOAD(&msg.n);489 490 na = (struct nlattr *) GENLMSG_DATA(&msg);491 len = 0;492 while (len < rep_len) {493 len += NLA_ALIGN(na->nla_len);494 switch (na->nla_type) {495 case TASKSTATS_TYPE_AGGR_TGID:496 /* Fall through */497 case TASKSTATS_TYPE_AGGR_PID:498 aggr_len = NLA_PAYLOAD(na->nla_len);499 len2 = 0;500 /* For nested attributes, na follows */501 na = (struct nlattr *) NLA_DATA(na);502 while (len2 < aggr_len) {503 switch (na->nla_type) {504 case TASKSTATS_TYPE_PID:505 rtid = *(int *) NLA_DATA(na);506 if (print_delays)507 printf("PID\t%d\n", rtid);508 break;509 case TASKSTATS_TYPE_TGID:510 rtid = *(int *) NLA_DATA(na);511 if (print_delays)512 printf("TGID\t%d\n", rtid);513 break;514 case TASKSTATS_TYPE_STATS:515 if (print_delays)516 print_delayacct((struct taskstats *) NLA_DATA(na));517 if (print_io_accounting)518 print_ioacct((struct taskstats *) NLA_DATA(na));519 if (print_task_context_switch_counts)520 task_context_switch_counts((struct taskstats *) NLA_DATA(na));521 if (fd) {522 if (write(fd, NLA_DATA(na), na->nla_len) < 0) {523 err(1,"write error\n");524 }525 }526 if (!loop)527 goto done;528 break;529 case TASKSTATS_TYPE_NULL:530 break;531 default:532 fprintf(stderr, "Unknown nested"533 " nla_type %d\n",534 na->nla_type);535 break;536 }537 len2 += NLA_ALIGN(na->nla_len);538 na = (struct nlattr *)((char *)na +539 NLA_ALIGN(na->nla_len));540 }541 break;542 543 case CGROUPSTATS_TYPE_CGROUP_STATS:544 print_cgroupstats(NLA_DATA(na));545 break;546 default:547 fprintf(stderr, "Unknown nla_type %d\n",548 na->nla_type);549 case TASKSTATS_TYPE_NULL:550 break;551 }552 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);553 }554 } while (loop);555done:556 if (maskset) {557 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,558 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,559 &cpumask, strlen(cpumask) + 1);560 printf("Sent deregister mask, retval %d\n", rc);561 if (rc < 0)562 err(rc, "error sending deregister cpumask\n");563 }564err:565 close(nl_sd);566 if (fd)567 close(fd);568 if (cfd)569 close(cfd);570 return 0;571}572