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