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/types.h>
  25 #include <signal.h>
  26
  27 #include <linux/genetlink.h>
  28 #include <linux/taskstats.h>
  29
  30 /*
  31  * Generic macros for dealing with netlink sockets. Might be duplicated
  32  * elsewhere. It is recommended that commercial grade applications use
  33  * libnl or libnetlink and use the interfaces provided by the library
  34  */
  35 #define GENLMSG_DATA(glh)       ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN))
  36 #define GENLMSG_PAYLOAD(glh)    (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN)
  37 #define NLA_DATA(na)            ((void *)((char*)(na) + NLA_HDRLEN))
  38 #define NLA_PAYLOAD(len)        (len - NLA_HDRLEN)
  39
  40 #define err(code, fmt, arg...)                  \
  41         do {                                    \
  42                 fprintf(stderr, fmt, ##arg);    \
  43                 exit(code);                     \
  44         } while (0)
  45
  46 int done;
  47 int rcvbufsz;
  48 char name[100];
  49 int dbg;
  50 int print_delays;
  51 int print_io_accounting;
  52 int print_task_context_switch_counts;
  53 __u64 stime, utime;
  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 }
  83
  84 /*
  85  * Create a raw netlink socket and bind
  86  */
  87 static int create_nl_socket(int protocol)
  88 {
  89         int fd;
  90         struct sockaddr_nl local;
  91
  92         fd = socket(AF_NETLINK, SOCK_RAW, protocol);
  93         if (fd < 0)
  94                 return -1;
  95
  96         if (rcvbufsz)
  97                 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
  98                                 &rcvbufsz, sizeof(rcvbufsz)) < 0) {
  99                         fprintf(stderr, "Unable to set socket rcv buf size "
 100                                         "to %d\n",
 101                                 rcvbufsz);
 102                         return -1;
 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 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 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, 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
 179         rep_len = recv(sd, &ans, sizeof(ans), 0);
 180         if (ans.n.nlmsg_type == NLMSG_ERROR ||
 181             (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
 182                 return 0;
 183
 184         na = (struct nlattr *) GENLMSG_DATA(&ans);
 185         na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
 186         if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
 187                 id = *(__u16 *) NLA_DATA(na);
 188         }
 189         return id;
 190 }
 191
 192 void print_delayacct(struct taskstats *t)
 193 {
 194         printf("\n\nCPU   %15s%15s%15s%15s\n"
 195                "      %15llu%15llu%15llu%15llu\n"
 196                "IO    %15s%15s\n"
 197                "      %15llu%15llu\n"
 198                "MEM   %15s%15s\n"
 199                "      %15llu%15llu\n"
 200                "count", "real total", "virtual total", "delay total",
 201                t->cpu_count, t->cpu_run_real_total, t->cpu_run_virtual_total,
 202                t->cpu_delay_total,
 203                "count", "delay total",
 204                t->blkio_count, t->blkio_delay_total,
 205                "count", "delay total", t->swapin_count, t->swapin_delay_total);
 206 }
 207
 208 void task_context_switch_counts(struct taskstats *t)
 209 {
 210         printf("\n\nTask   %15s%15s\n"
 211                "       %15lu%15lu\n",
 212                "voluntary", "nonvoluntary",
 213                t->nvcsw, t->nivcsw);
 214 }
 215
 216 void print_ioacct(struct taskstats *t)
 217 {
 218         printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
 219                 t->ac_comm,
 220                 (unsigned long long)t->read_bytes,
 221                 (unsigned long long)t->write_bytes,
 222                 (unsigned long long)t->cancelled_write_bytes);
 223 }
 224
 225 int main(int argc, char *argv[])
 226 {
 227         int c, rc, rep_len, aggr_len, len2, cmd_type;
 228         __u16 id;
 229         __u32 mypid;
 230
 231         struct nlattr *na;
 232         int nl_sd = -1;
 233         int len = 0;
 234         pid_t tid = 0;
 235         pid_t rtid = 0;
 236
 237         int fd = 0;
 238         int count = 0;
 239         int write_file = 0;
 240         int maskset = 0;
 241         char *logfile = NULL;
 242         int loop = 0;
 243
 244         struct msgtemplate msg;
 245
 246         while (1) {
 247                 c = getopt(argc, argv, "qdiw:r:m:t:p:vl");
 248                 if (c < 0)
 249                         break;
 250
 251                 switch (c) {
 252                 case 'd':
 253                         printf("print delayacct stats ON\n");
 254                         print_delays = 1;
 255                         break;
 256                 case 'i':
 257                         printf("printing IO accounting\n");
 258                         print_io_accounting = 1;
 259                         break;
 260                 case 'q':
 261                         printf("printing task/process context switch rates\n");
 262                         print_task_context_switch_counts = 1;
 263                         break;
 264                 case 'w':
 265                         logfile = strdup(optarg);
 266                         printf("write to file %s\n", logfile);
 267                         write_file = 1;
 268                         break;
 269                 case 'r':
 270                         rcvbufsz = atoi(optarg);
 271                         printf("receive buf size %d\n", rcvbufsz);
 272                         if (rcvbufsz < 0)
 273                                 err(1, "Invalid rcv buf size\n");
 274                         break;
 275                 case 'm':
 276                         strncpy(cpumask, optarg, sizeof(cpumask));
 277                         maskset = 1;
 278                         printf("cpumask %s maskset %d\n", cpumask, maskset);
 279                         break;
 280                 case 't':
 281                         tid = atoi(optarg);
 282                         if (!tid)
 283                                 err(1, "Invalid tgid\n");
 284                         cmd_type = TASKSTATS_CMD_ATTR_TGID;
 285                         break;
 286                 case 'p':
 287                         tid = atoi(optarg);
 288                         if (!tid)
 289                                 err(1, "Invalid pid\n");
 290                         cmd_type = TASKSTATS_CMD_ATTR_PID;
 291                         break;
 292                 case 'v':
 293                         printf("debug on\n");
 294                         dbg = 1;
 295                         break;
 296                 case 'l':
 297                         printf("listen forever\n");
 298                         loop = 1;
 299                         break;
 300                 default:
 301                         usage();
 302                         exit(-1);
 303                 }
 304         }
 305
 306         if (write_file) {
 307                 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
 308                           S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
 309                 if (fd == -1) {
 310                         perror("Cannot open output file\n");
 311                         exit(1);
 312                 }
 313         }
 314
 315         if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0)
 316                 err(1, "error creating Netlink socket\n");
 317
 318
 319         mypid = getpid();
 320         id = get_family_id(nl_sd);
 321         if (!id) {
 322                 fprintf(stderr, "Error getting family id, errno %d\n", errno);
 323                 goto err;
 324         }
 325         PRINTF("family id %d\n", id);
 326
 327         if (maskset) {
 328                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 329                               TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
 330                               &cpumask, strlen(cpumask) + 1);
 331                 PRINTF("Sent register cpumask, retval %d\n", rc);
 332                 if (rc < 0) {
 333                         fprintf(stderr, "error sending register cpumask\n");
 334                         goto err;
 335                 }
 336         }
 337
 338         if (tid) {
 339                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 340                               cmd_type, &tid, sizeof(__u32));
 341                 PRINTF("Sent pid/tgid, retval %d\n", rc);
 342                 if (rc < 0) {
 343                         fprintf(stderr, "error sending tid/tgid cmd\n");
 344                         goto done;
 345                 }
 346         }
 347
 348         do {
 349                 int i;
 350
 351                 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
 352                 PRINTF("received %d bytes\n", rep_len);
 353
 354                 if (rep_len < 0) {
 355                         fprintf(stderr, "nonfatal reply error: errno %d\n",
 356                                 errno);
 357                         continue;
 358                 }
 359                 if (msg.n.nlmsg_type == NLMSG_ERROR ||
 360                     !NLMSG_OK((&msg.n), rep_len)) {
 361                         struct nlmsgerr *err = NLMSG_DATA(&msg);
 362                         fprintf(stderr, "fatal reply error,  errno %d\n",
 363                                 err->error);
 364                         goto done;
 365                 }
 366
 367                 PRINTF("nlmsghdr size=%d, nlmsg_len=%d, rep_len=%d\n",
 368                        sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
 369
 370
 371                 rep_len = GENLMSG_PAYLOAD(&msg.n);
 372
 373                 na = (struct nlattr *) GENLMSG_DATA(&msg);
 374                 len = 0;
 375                 i = 0;
 376                 while (len < rep_len) {
 377                         len += NLA_ALIGN(na->nla_len);
 378                         switch (na->nla_type) {
 379                         case TASKSTATS_TYPE_AGGR_TGID:
 380                                 /* Fall through */
 381                         case TASKSTATS_TYPE_AGGR_PID:
 382                                 aggr_len = NLA_PAYLOAD(na->nla_len);
 383                                 len2 = 0;
 384                                 /* For nested attributes, na follows */
 385                                 na = (struct nlattr *) NLA_DATA(na);
 386                                 done = 0;
 387                                 while (len2 < aggr_len) {
 388                                         switch (na->nla_type) {
 389                                         case TASKSTATS_TYPE_PID:
 390                                                 rtid = *(int *) NLA_DATA(na);
 391                                                 if (print_delays)
 392                                                         printf("PID\t%d\n", rtid);
 393                                                 break;
 394                                         case TASKSTATS_TYPE_TGID:
 395                                                 rtid = *(int *) NLA_DATA(na);
 396                                                 if (print_delays)
 397                                                         printf("TGID\t%d\n", rtid);
 398                                                 break;
 399                                         case TASKSTATS_TYPE_STATS:
 400                                                 count++;
 401                                                 if (print_delays)
 402                                                         print_delayacct((struct taskstats *) NLA_DATA(na));
 403                                                 if (print_io_accounting)
 404                                                         print_ioacct((struct taskstats *) NLA_DATA(na));
 405                                                 if (print_task_context_switch_counts)
 406                                                         task_context_switch_counts((struct taskstats *) NLA_DATA(na));
 407                                                 if (fd) {
 408                                                         if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
 409                                                                 err(1,"write error\n");
 410                                                         }
 411                                                 }
 412                                                 if (!loop)
 413                                                         goto done;
 414                                                 break;
 415                                         default:
 416                                                 fprintf(stderr, "Unknown nested"
 417                                                         " nla_type %d\n",
 418                                                         na->nla_type);
 419                                                 break;
 420                                         }
 421                                         len2 += NLA_ALIGN(na->nla_len);
 422                                         na = (struct nlattr *) ((char *) na + len2);
 423                                 }
 424                                 break;
 425
 426                         default:
 427                                 fprintf(stderr, "Unknown nla_type %d\n",
 428                                         na->nla_type);
 429                                 break;
 430                         }
 431                         na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
 432                 }
 433         } while (loop);
 434 done:
 435         if (maskset) {
 436                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 437                               TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
 438                               &cpumask, strlen(cpumask) + 1);
 439                 printf("Sent deregister mask, retval %d\n", rc);
 440                 if (rc < 0)
 441                         err(rc, "error sending deregister cpumask\n");
 442         }
 443 err:
 444         close(nl_sd);
 445         if (fd)
 446                 close(fd);
 447         return 0;
 448 }