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 __u64 stime, utime;
  53
  54 #define PRINTF(fmt, arg...) {                   \
  55             if (dbg) {                          \
  56                 printf(fmt, ##arg);             \
  57             }                                   \
  58         }
  59
  60 /* Maximum size of response requested or message sent */
  61 #define MAX_MSG_SIZE    1024
  62 /* Maximum number of cpus expected to be specified in a cpumask */
  63 #define MAX_CPUS        32
  64
  65 struct msgtemplate {
  66         struct nlmsghdr n;
  67         struct genlmsghdr g;
  68         char buf[MAX_MSG_SIZE];
  69 };
  70
  71 char cpumask[100+6*MAX_CPUS];
  72
  73 static void usage(void)
  74 {
  75         fprintf(stderr, "getdelays [-dilv] [-w logfile] [-r bufsize] "
  76                         "[-m cpumask] [-t tgid] [-p pid]\n");
  77         fprintf(stderr, "  -d: print delayacct stats\n");
  78         fprintf(stderr, "  -i: print IO accounting (works only with -p)\n");
  79         fprintf(stderr, "  -l: listen forever\n");
  80         fprintf(stderr, "  -v: debug on\n");
  81 }
  82
  83 /*
  84  * Create a raw netlink socket and bind
  85  */
  86 static int create_nl_socket(int protocol)
  87 {
  88         int fd;
  89         struct sockaddr_nl local;
  90
  91         fd = socket(AF_NETLINK, SOCK_RAW, protocol);
  92         if (fd < 0)
  93                 return -1;
  94
  95         if (rcvbufsz)
  96                 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
  97                                 &rcvbufsz, sizeof(rcvbufsz)) < 0) {
  98                         fprintf(stderr, "Unable to set socket rcv buf size "
  99                                         "to %d\n",
 100                                 rcvbufsz);
 101                         return -1;
 102                 }
 103
 104         memset(&local, 0, sizeof(local));
 105         local.nl_family = AF_NETLINK;
 106
 107         if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
 108                 goto error;
 109
 110         return fd;
 111 error:
 112         close(fd);
 113         return -1;
 114 }
 115
 116
 117 int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid,
 118              __u8 genl_cmd, __u16 nla_type,
 119              void *nla_data, int nla_len)
 120 {
 121         struct nlattr *na;
 122         struct sockaddr_nl nladdr;
 123         int r, buflen;
 124         char *buf;
 125
 126         struct msgtemplate msg;
 127
 128         msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
 129         msg.n.nlmsg_type = nlmsg_type;
 130         msg.n.nlmsg_flags = NLM_F_REQUEST;
 131         msg.n.nlmsg_seq = 0;
 132         msg.n.nlmsg_pid = nlmsg_pid;
 133         msg.g.cmd = genl_cmd;
 134         msg.g.version = 0x1;
 135         na = (struct nlattr *) GENLMSG_DATA(&msg);
 136         na->nla_type = nla_type;
 137         na->nla_len = nla_len + 1 + NLA_HDRLEN;
 138         memcpy(NLA_DATA(na), nla_data, nla_len);
 139         msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len);
 140
 141         buf = (char *) &msg;
 142         buflen = msg.n.nlmsg_len ;
 143         memset(&nladdr, 0, sizeof(nladdr));
 144         nladdr.nl_family = AF_NETLINK;
 145         while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr,
 146                            sizeof(nladdr))) < buflen) {
 147                 if (r > 0) {
 148                         buf += r;
 149                         buflen -= r;
 150                 } else if (errno != EAGAIN)
 151                         return -1;
 152         }
 153         return 0;
 154 }
 155
 156
 157 /*
 158  * Probe the controller in genetlink to find the family id
 159  * for the TASKSTATS family
 160  */
 161 int get_family_id(int sd)
 162 {
 163         struct {
 164                 struct nlmsghdr n;
 165                 struct genlmsghdr g;
 166                 char buf[256];
 167         } ans;
 168
 169         int id, rc;
 170         struct nlattr *na;
 171         int rep_len;
 172
 173         strcpy(name, TASKSTATS_GENL_NAME);
 174         rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
 175                         CTRL_ATTR_FAMILY_NAME, (void *)name,
 176                         strlen(TASKSTATS_GENL_NAME)+1);
 177
 178         rep_len = recv(sd, &ans, sizeof(ans), 0);
 179         if (ans.n.nlmsg_type == NLMSG_ERROR ||
 180             (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
 181                 return 0;
 182
 183         na = (struct nlattr *) GENLMSG_DATA(&ans);
 184         na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
 185         if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
 186                 id = *(__u16 *) NLA_DATA(na);
 187         }
 188         return id;
 189 }
 190
 191 void print_delayacct(struct taskstats *t)
 192 {
 193         printf("\n\nCPU   %15s%15s%15s%15s\n"
 194                "      %15llu%15llu%15llu%15llu\n"
 195                "IO    %15s%15s\n"
 196                "      %15llu%15llu\n"
 197                "MEM   %15s%15s\n"
 198                "      %15llu%15llu\n\n",
 199                "count", "real total", "virtual total", "delay total",
 200                t->cpu_count, t->cpu_run_real_total, t->cpu_run_virtual_total,
 201                t->cpu_delay_total,
 202                "count", "delay total",
 203                t->blkio_count, t->blkio_delay_total,
 204                "count", "delay total", t->swapin_count, t->swapin_delay_total);
 205 }
 206
 207 void print_ioacct(struct taskstats *t)
 208 {
 209         printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
 210                 t->ac_comm,
 211                 (unsigned long long)t->read_bytes,
 212                 (unsigned long long)t->write_bytes,
 213                 (unsigned long long)t->cancelled_write_bytes);
 214 }
 215
 216 int main(int argc, char *argv[])
 217 {
 218         int c, rc, rep_len, aggr_len, len2, cmd_type;
 219         __u16 id;
 220         __u32 mypid;
 221
 222         struct nlattr *na;
 223         int nl_sd = -1;
 224         int len = 0;
 225         pid_t tid = 0;
 226         pid_t rtid = 0;
 227
 228         int fd = 0;
 229         int count = 0;
 230         int write_file = 0;
 231         int maskset = 0;
 232         char *logfile = NULL;
 233         int loop = 0;
 234
 235         struct msgtemplate msg;
 236
 237         while (1) {
 238                 c = getopt(argc, argv, "diw:r:m:t:p:vl");
 239                 if (c < 0)
 240                         break;
 241
 242                 switch (c) {
 243                 case 'd':
 244                         printf("print delayacct stats ON\n");
 245                         print_delays = 1;
 246                         break;
 247                 case 'i':
 248                         printf("printing IO accounting\n");
 249                         print_io_accounting = 1;
 250                         break;
 251                 case 'w':
 252                         logfile = strdup(optarg);
 253                         printf("write to file %s\n", logfile);
 254                         write_file = 1;
 255                         break;
 256                 case 'r':
 257                         rcvbufsz = atoi(optarg);
 258                         printf("receive buf size %d\n", rcvbufsz);
 259                         if (rcvbufsz < 0)
 260                                 err(1, "Invalid rcv buf size\n");
 261                         break;
 262                 case 'm':
 263                         strncpy(cpumask, optarg, sizeof(cpumask));
 264                         maskset = 1;
 265                         printf("cpumask %s maskset %d\n", cpumask, maskset);
 266                         break;
 267                 case 't':
 268                         tid = atoi(optarg);
 269                         if (!tid)
 270                                 err(1, "Invalid tgid\n");
 271                         cmd_type = TASKSTATS_CMD_ATTR_TGID;
 272                         break;
 273                 case 'p':
 274                         tid = atoi(optarg);
 275                         if (!tid)
 276                                 err(1, "Invalid pid\n");
 277                         cmd_type = TASKSTATS_CMD_ATTR_PID;
 278                         break;
 279                 case 'v':
 280                         printf("debug on\n");
 281                         dbg = 1;
 282                         break;
 283                 case 'l':
 284                         printf("listen forever\n");
 285                         loop = 1;
 286                         break;
 287                 default:
 288                         usage();
 289                         exit(-1);
 290                 }
 291         }
 292
 293         if (write_file) {
 294                 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
 295                           S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
 296                 if (fd == -1) {
 297                         perror("Cannot open output file\n");
 298                         exit(1);
 299                 }
 300         }
 301
 302         if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0)
 303                 err(1, "error creating Netlink socket\n");
 304
 305
 306         mypid = getpid();
 307         id = get_family_id(nl_sd);
 308         if (!id) {
 309                 fprintf(stderr, "Error getting family id, errno %d\n", errno);
 310                 goto err;
 311         }
 312         PRINTF("family id %d\n", id);
 313
 314         if (maskset) {
 315                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 316                               TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
 317                               &cpumask, strlen(cpumask) + 1);
 318                 PRINTF("Sent register cpumask, retval %d\n", rc);
 319                 if (rc < 0) {
 320                         fprintf(stderr, "error sending register cpumask\n");
 321                         goto err;
 322                 }
 323         }
 324
 325         if (tid) {
 326                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 327                               cmd_type, &tid, sizeof(__u32));
 328                 PRINTF("Sent pid/tgid, retval %d\n", rc);
 329                 if (rc < 0) {
 330                         fprintf(stderr, "error sending tid/tgid cmd\n");
 331                         goto done;
 332                 }
 333         }
 334
 335         do {
 336                 int i;
 337
 338                 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
 339                 PRINTF("received %d bytes\n", rep_len);
 340
 341                 if (rep_len < 0) {
 342                         fprintf(stderr, "nonfatal reply error: errno %d\n",
 343                                 errno);
 344                         continue;
 345                 }
 346                 if (msg.n.nlmsg_type == NLMSG_ERROR ||
 347                     !NLMSG_OK((&msg.n), rep_len)) {
 348                         struct nlmsgerr *err = NLMSG_DATA(&msg);
 349                         fprintf(stderr, "fatal reply error,  errno %d\n",
 350                                 err->error);
 351                         goto done;
 352                 }
 353
 354                 PRINTF("nlmsghdr size=%d, nlmsg_len=%d, rep_len=%d\n",
 355                        sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
 356
 357
 358                 rep_len = GENLMSG_PAYLOAD(&msg.n);
 359
 360                 na = (struct nlattr *) GENLMSG_DATA(&msg);
 361                 len = 0;
 362                 i = 0;
 363                 while (len < rep_len) {
 364                         len += NLA_ALIGN(na->nla_len);
 365                         switch (na->nla_type) {
 366                         case TASKSTATS_TYPE_AGGR_TGID:
 367                                 /* Fall through */
 368                         case TASKSTATS_TYPE_AGGR_PID:
 369                                 aggr_len = NLA_PAYLOAD(na->nla_len);
 370                                 len2 = 0;
 371                                 /* For nested attributes, na follows */
 372                                 na = (struct nlattr *) NLA_DATA(na);
 373                                 done = 0;
 374                                 while (len2 < aggr_len) {
 375                                         switch (na->nla_type) {
 376                                         case TASKSTATS_TYPE_PID:
 377                                                 rtid = *(int *) NLA_DATA(na);
 378                                                 if (print_delays)
 379                                                         printf("PID\t%d\n", rtid);
 380                                                 break;
 381                                         case TASKSTATS_TYPE_TGID:
 382                                                 rtid = *(int *) NLA_DATA(na);
 383                                                 if (print_delays)
 384                                                         printf("TGID\t%d\n", rtid);
 385                                                 break;
 386                                         case TASKSTATS_TYPE_STATS:
 387                                                 count++;
 388                                                 if (print_delays)
 389                                                         print_delayacct((struct taskstats *) NLA_DATA(na));
 390                                                 if (print_io_accounting)
 391                                                         print_ioacct((struct taskstats *) NLA_DATA(na));
 392                                                 if (fd) {
 393                                                         if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
 394                                                                 err(1,"write error\n");
 395                                                         }
 396                                                 }
 397                                                 if (!loop)
 398                                                         goto done;
 399                                                 break;
 400                                         default:
 401                                                 fprintf(stderr, "Unknown nested"
 402                                                         " nla_type %d\n",
 403                                                         na->nla_type);
 404                                                 break;
 405                                         }
 406                                         len2 += NLA_ALIGN(na->nla_len);
 407                                         na = (struct nlattr *) ((char *) na + len2);
 408                                 }
 409                                 break;
 410
 411                         default:
 412                                 fprintf(stderr, "Unknown nla_type %d\n",
 413                                         na->nla_type);
 414                                 break;
 415                         }
 416                         na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
 417                 }
 418         } while (loop);
 419 done:
 420         if (maskset) {
 421                 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
 422                               TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
 423                               &cpumask, strlen(cpumask) + 1);
 424                 printf("Sent deregister mask, retval %d\n", rc);
 425                 if (rc < 0)
 426                         err(rc, "error sending deregister cpumask\n");
 427         }
 428 err:
 429         close(nl_sd);
 430         if (fd)
 431                 close(fd);
 432         return 0;
 433 }