Documentation/accounting/getdelays.c

   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 __u64 stime, utime;
  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 + 1 + 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                "count", "real total", "virtual total",
 208                "delay total", "delay average",
 209                (unsigned long long)t->cpu_count,
 210                (unsigned long long)t->cpu_run_real_total,
 211                (unsigned long long)t->cpu_run_virtual_total,
 212                (unsigned long long)t->cpu_delay_total,
 213                average_ms((double)t->cpu_delay_total, t->cpu_count),
 214                "count", "delay total", "delay average",
 215                (unsigned long long)t->blkio_count,
 216                (unsigned long long)t->blkio_delay_total,
 217                average_ms(t->blkio_delay_total, t->blkio_count),
 218                "count", "delay total", "delay average",
 219                (unsigned long long)t->swapin_count,
 220                (unsigned long long)t->swapin_delay_total,
 221                average_ms(t->swapin_delay_total, t->swapin_count),
 222                "count", "delay total", "delay average",
 223                (unsigned long long)t->freepages_count,
 224                (unsigned long long)t->freepages_delay_total,
 225                average_ms(t->freepages_delay_total, t->freepages_count));
 226 }
 227
 228 static void task_context_switch_counts(struct taskstats *t)
 229 {
 230         printf("\n\nTask   %15s%15s\n"
 231                "       %15llu%15llu\n",
 232                "voluntary", "nonvoluntary",
 233                (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);
 234 }
 235
 236 static void print_cgroupstats(struct cgroupstats *c)
 237 {
 238         printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, "
 239                 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,
 240                 (unsigned long long)c->nr_io_wait,
 241                 (unsigned long long)c->nr_running,
 242                 (unsigned long long)c->nr_stopped,
 243                 (unsigned long long)c->nr_uninterruptible);
 244 }
 245
 246
 247 static void print_ioacct(struct taskstats *t)
 248 {
 249         printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
 250                 t->ac_comm,
 251                 (unsigned long long)t->read_bytes,
 252                 (unsigned long long)t->write_bytes,
 253                 (unsigned long long)t->cancelled_write_bytes);
 254 }
 255
 256 int main(int argc, char *argv[])
 257 {
 258         int c, rc, rep_len, aggr_len, len2;
 259         int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;
 260         __u16 id;
 261         __u32 mypid;
 262
 263         struct nlattr *na;
 264         int nl_sd = -1;
 265         int len = 0;
 266         pid_t tid = 0;
 267         pid_t rtid = 0;
 268
 269         int fd = 0;
 270         int count = 0;
 271         int write_file = 0;
 272         int maskset = 0;
 273         char *logfile = NULL;
 274         int loop = 0;
 275         int containerset = 0;
 276         char containerpath[1024];
 277         int cfd = 0;
 278         int forking = 0;
 279         sigset_t sigset;
 280
 281         struct msgtemplate msg;
 282
 283         while (!forking) {
 284                 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
 285                 if (c < 0)
 286                         break;
 287
 288                 switch (c) {
 289                 case 'd':
 290                         printf("print delayacct stats ON\n");
 291                         print_delays = 1;
 292                         break;
 293                 case 'i':
 294                         printf("printing IO accounting\n");
 295                         print_io_accounting = 1;
 296                         break;
 297                 case 'q':
 298                         printf("printing task/process context switch rates\n");
 299                         print_task_context_switch_counts = 1;
 300                         break;
 301                 case 'C':
 302                         containerset = 1;
 303                         strncpy(containerpath, optarg, strlen(optarg) + 1);
 304                         break;
 305                 case 'w':
 306                         logfile = strdup(optarg);
 307                         printf("write to file %s\n", logfile);
 308                         write_file = 1;
 309                         break;
 310                 case 'r':
 311                         rcvbufsz = atoi(optarg);
 312                         printf("receive buf size %d\n", rcvbufsz);
 313                         if (rcvbufsz < 0)
 314                                 err(1, "Invalid rcv buf size\n");
 315                         break;
 316                 case 'm':
 317                         strncpy(cpumask, optarg, sizeof(cpumask));
 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         if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0)
 379                 err(1, "error creating Netlink socket\n");
 380
 381
 382         mypid = getpid();
 383         id = get_family_id(nl_sd);
 384         if (!id) {
 385                 fprintf(stderr, "Error getting family id, errno %d\n", errno);
 386                 goto err;
 387         }
 388         PRINTF("family id %d\n", id);
 389
 390         if (maskset) {
 391                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 392                               TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
 393                               &cpumask, strlen(cpumask) + 1);
 394                 PRINTF("Sent register cpumask, retval %d\n", rc);
 395                 if (rc < 0) {
 396                         fprintf(stderr, "error sending register cpumask\n");
 397                         goto err;
 398                 }
 399         }
 400
 401         if (tid && containerset) {
 402                 fprintf(stderr, "Select either -t or -C, not both\n");
 403                 goto err;
 404         }
 405
 406         /*
 407          * If we forked a child, wait for it to exit. Cannot use waitpid()
 408          * as all the delicious data would be reaped as part of the wait
 409          */
 410         if (tid && forking) {
 411                 int sig_received;
 412                 sigwait(&sigset, &sig_received);
 413         }
 414
 415         if (tid) {
 416                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 417                               cmd_type, &tid, sizeof(__u32));
 418                 PRINTF("Sent pid/tgid, retval %d\n", rc);
 419                 if (rc < 0) {
 420                         fprintf(stderr, "error sending tid/tgid cmd\n");
 421                         goto done;
 422                 }
 423         }
 424
 425         if (containerset) {
 426                 cfd = open(containerpath, O_RDONLY);
 427                 if (cfd < 0) {
 428                         perror("error opening container file");
 429                         goto err;
 430                 }
 431                 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,
 432                               CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));
 433                 if (rc < 0) {
 434                         perror("error sending cgroupstats command");
 435                         goto err;
 436                 }
 437         }
 438         if (!maskset && !tid && !containerset) {
 439                 usage();
 440                 goto err;
 441         }
 442
 443         do {
 444                 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
 445                 PRINTF("received %d bytes\n", rep_len);
 446
 447                 if (rep_len < 0) {
 448                         fprintf(stderr, "nonfatal reply error: errno %d\n",
 449                                 errno);
 450                         continue;
 451                 }
 452                 if (msg.n.nlmsg_type == NLMSG_ERROR ||
 453                     !NLMSG_OK((&msg.n), rep_len)) {
 454                         struct nlmsgerr *err = NLMSG_DATA(&msg);
 455                         fprintf(stderr, "fatal reply error,  errno %d\n",
 456                                 err->error);
 457                         goto done;
 458                 }
 459
 460                 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
 461                        sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
 462
 463
 464                 rep_len = GENLMSG_PAYLOAD(&msg.n);
 465
 466                 na = (struct nlattr *) GENLMSG_DATA(&msg);
 467                 len = 0;
 468                 while (len < rep_len) {
 469                         len += NLA_ALIGN(na->nla_len);
 470                         switch (na->nla_type) {
 471                         case TASKSTATS_TYPE_AGGR_TGID:
 472                                 /* Fall through */
 473                         case TASKSTATS_TYPE_AGGR_PID:
 474                                 aggr_len = NLA_PAYLOAD(na->nla_len);
 475                                 len2 = 0;
 476                                 /* For nested attributes, na follows */
 477                                 na = (struct nlattr *) NLA_DATA(na);
 478                                 done = 0;
 479                                 while (len2 < aggr_len) {
 480                                         switch (na->nla_type) {
 481                                         case TASKSTATS_TYPE_PID:
 482                                                 rtid = *(int *) NLA_DATA(na);
 483                                                 if (print_delays)
 484                                                         printf("PID\t%d\n", rtid);
 485                                                 break;
 486                                         case TASKSTATS_TYPE_TGID:
 487                                                 rtid = *(int *) NLA_DATA(na);
 488                                                 if (print_delays)
 489                                                         printf("TGID\t%d\n", rtid);
 490                                                 break;
 491                                         case TASKSTATS_TYPE_STATS:
 492                                                 count++;
 493                                                 if (print_delays)
 494                                                         print_delayacct((struct taskstats *) NLA_DATA(na));
 495                                                 if (print_io_accounting)
 496                                                         print_ioacct((struct taskstats *) NLA_DATA(na));
 497                                                 if (print_task_context_switch_counts)
 498                                                         task_context_switch_counts((struct taskstats *) NLA_DATA(na));
 499                                                 if (fd) {
 500                                                         if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
 501                                                                 err(1,"write error\n");
 502                                                         }
 503                                                 }
 504                                                 if (!loop)
 505                                                         goto done;
 506                                                 break;
 507                                         default:
 508                                                 fprintf(stderr, "Unknown nested"
 509                                                         " nla_type %d\n",
 510                                                         na->nla_type);
 511                                                 break;
 512                                         }
 513                                         len2 += NLA_ALIGN(na->nla_len);
 514                                         na = (struct nlattr *) ((char *) na + len2);
 515                                 }
 516                                 break;
 517
 518                         case CGROUPSTATS_TYPE_CGROUP_STATS:
 519                                 print_cgroupstats(NLA_DATA(na));
 520                                 break;
 521                         default:
 522                                 fprintf(stderr, "Unknown nla_type %d\n",
 523                                         na->nla_type);
 524                         case TASKSTATS_TYPE_NULL:
 525                                 break;
 526                         }
 527                         na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
 528                 }
 529         } while (loop);
 530 done:
 531         if (maskset) {
 532                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 533                               TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
 534                               &cpumask, strlen(cpumask) + 1);
 535                 printf("Sent deregister mask, retval %d\n", rc);
 536                 if (rc < 0)
 537                         err(rc, "error sending deregister cpumask\n");
 538         }
 539 err:
 540         close(nl_sd);
 541         if (fd)
 542                 close(fd);
 543         if (cfd)
 544                 close(cfd);
 545         return 0;
 546 }