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
usage(void)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 */
create_nl_socket(int protocol)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 "
102 "to %d\n",
103 rcvbufsz);
104 return -1;
105 }
106
107 memset(&local, 0, sizeof(local));
108 local.nl_family = AF_NETLINK;
109
110 if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
111 goto error;
112
113 return fd;
114 error:
115 close(fd);
116 return -1;
117 }
118
119
send_cmd(int sd,__u16 nlmsg_type,__u32 nlmsg_pid,__u8 genl_cmd,__u16 nla_type,void * nla_data,int nla_len)120 static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid,
121 __u8 genl_cmd, __u16 nla_type,
122 void *nla_data, int nla_len)
123 {
124 struct nlattr *na;
125 struct sockaddr_nl nladdr;
126 int r, buflen;
127 char *buf;
128
129 struct msgtemplate msg;
130
131 msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
132 msg.n.nlmsg_type = nlmsg_type;
133 msg.n.nlmsg_flags = NLM_F_REQUEST;
134 msg.n.nlmsg_seq = 0;
135 msg.n.nlmsg_pid = nlmsg_pid;
136 msg.g.cmd = genl_cmd;
137 msg.g.version = 0x1;
138 na = (struct nlattr *) GENLMSG_DATA(&msg);
139 na->nla_type = nla_type;
140 na->nla_len = nla_len + 1 + NLA_HDRLEN;
141 memcpy(NLA_DATA(na), nla_data, nla_len);
142 msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len);
143
144 buf = (char *) &msg;
145 buflen = msg.n.nlmsg_len ;
146 memset(&nladdr, 0, sizeof(nladdr));
147 nladdr.nl_family = AF_NETLINK;
148 while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr,
149 sizeof(nladdr))) < buflen) {
150 if (r > 0) {
151 buf += r;
152 buflen -= r;
153 } else if (errno != EAGAIN)
154 return -1;
155 }
156 return 0;
157 }
158
159
160 /*
161 * Probe the controller in genetlink to find the family id
162 * for the TASKSTATS family
163 */
get_family_id(int sd)164 static int get_family_id(int sd)
165 {
166 struct {
167 struct nlmsghdr n;
168 struct genlmsghdr g;
169 char buf[256];
170 } ans;
171
172 int id = 0, rc;
173 struct nlattr *na;
174 int rep_len;
175
176 strcpy(name, TASKSTATS_GENL_NAME);
177 rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
178 CTRL_ATTR_FAMILY_NAME, (void *)name,
179 strlen(TASKSTATS_GENL_NAME)+1);
180 if (rc < 0)
181 return 0; /* sendto() failure? */
182
183 rep_len = recv(sd, &ans, sizeof(ans), 0);
184 if (ans.n.nlmsg_type == NLMSG_ERROR ||
185 (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
186 return 0;
187
188 na = (struct nlattr *) GENLMSG_DATA(&ans);
189 na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
190 if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
191 id = *(__u16 *) NLA_DATA(na);
192 }
193 return id;
194 }
195
196 #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1))
197
print_delayacct(struct taskstats * t)198 static void print_delayacct(struct taskstats *t)
199 {
200 printf("\n\nCPU %15s%15s%15s%15s%15s\n"
201 " %15llu%15llu%15llu%15llu%15.3fms\n"
202 "IO %15s%15s%15s\n"
203 " %15llu%15llu%15llums\n"
204 "SWAP %15s%15s%15s\n"
205 " %15llu%15llu%15llums\n"
206 "RECLAIM %12s%15s%15s\n"
207 " %15llu%15llu%15llums\n",
208 "count", "real total", "virtual total",
209 "delay total", "delay average",
210 (unsigned long long)t->cpu_count,
211 (unsigned long long)t->cpu_run_real_total,
212 (unsigned long long)t->cpu_run_virtual_total,
213 (unsigned long long)t->cpu_delay_total,
214 average_ms((double)t->cpu_delay_total, t->cpu_count),
215 "count", "delay total", "delay average",
216 (unsigned long long)t->blkio_count,
217 (unsigned long long)t->blkio_delay_total,
218 average_ms(t->blkio_delay_total, t->blkio_count),
219 "count", "delay total", "delay average",
220 (unsigned long long)t->swapin_count,
221 (unsigned long long)t->swapin_delay_total,
222 average_ms(t->swapin_delay_total, t->swapin_count),
223 "count", "delay total", "delay average",
224 (unsigned long long)t->freepages_count,
225 (unsigned long long)t->freepages_delay_total,
226 average_ms(t->freepages_delay_total, t->freepages_count));
227 }
228
task_context_switch_counts(struct taskstats * t)229 static void task_context_switch_counts(struct taskstats *t)
230 {
231 printf("\n\nTask %15s%15s\n"
232 " %15llu%15llu\n",
233 "voluntary", "nonvoluntary",
234 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);
235 }
236
print_cgroupstats(struct cgroupstats * c)237 static void print_cgroupstats(struct cgroupstats *c)
238 {
239 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, "
240 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,
241 (unsigned long long)c->nr_io_wait,
242 (unsigned long long)c->nr_running,
243 (unsigned long long)c->nr_stopped,
244 (unsigned long long)c->nr_uninterruptible);
245 }
246
247
print_ioacct(struct taskstats * t)248 static void print_ioacct(struct taskstats *t)
249 {
250 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
251 t->ac_comm,
252 (unsigned long long)t->read_bytes,
253 (unsigned long long)t->write_bytes,
254 (unsigned long long)t->cancelled_write_bytes);
255 }
256
main(int argc,char * argv[])257 int main(int argc, char *argv[])
258 {
259 int c, rc, rep_len, aggr_len, len2;
260 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;
261 __u16 id;
262 __u32 mypid;
263
264 struct nlattr *na;
265 int nl_sd = -1;
266 int len = 0;
267 pid_t tid = 0;
268 pid_t rtid = 0;
269
270 int fd = 0;
271 int count = 0;
272 int write_file = 0;
273 int maskset = 0;
274 char *logfile = NULL;
275 int loop = 0;
276 int containerset = 0;
277 char containerpath[1024];
278 int cfd = 0;
279 int forking = 0;
280 sigset_t sigset;
281
282 struct msgtemplate msg;
283
284 while (!forking) {
285 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
286 if (c < 0)
287 break;
288
289 switch (c) {
290 case 'd':
291 printf("print delayacct stats ON\n");
292 print_delays = 1;
293 break;
294 case 'i':
295 printf("printing IO accounting\n");
296 print_io_accounting = 1;
297 break;
298 case 'q':
299 printf("printing task/process context switch rates\n");
300 print_task_context_switch_counts = 1;
301 break;
302 case 'C':
303 containerset = 1;
304 strncpy(containerpath, optarg, strlen(optarg) + 1);
305 break;
306 case 'w':
307 logfile = strdup(optarg);
308 printf("write to file %s\n", logfile);
309 write_file = 1;
310 break;
311 case 'r':
312 rcvbufsz = atoi(optarg);
313 printf("receive buf size %d\n", rcvbufsz);
314 if (rcvbufsz < 0)
315 err(1, "Invalid rcv buf size\n");
316 break;
317 case 'm':
318 strncpy(cpumask, optarg, sizeof(cpumask));
319 maskset = 1;
320 printf("cpumask %s maskset %d\n", cpumask, maskset);
321 break;
322 case 't':
323 tid = atoi(optarg);
324 if (!tid)
325 err(1, "Invalid tgid\n");
326 cmd_type = TASKSTATS_CMD_ATTR_TGID;
327 break;
328 case 'p':
329 tid = atoi(optarg);
330 if (!tid)
331 err(1, "Invalid pid\n");
332 cmd_type = TASKSTATS_CMD_ATTR_PID;
333 break;
334 case 'c':
335
336 /* Block SIGCHLD for sigwait() later */
337 if (sigemptyset(&sigset) == -1)
338 err(1, "Failed to empty sigset");
339 if (sigaddset(&sigset, SIGCHLD))
340 err(1, "Failed to set sigchld in sigset");
341 sigprocmask(SIG_BLOCK, &sigset, NULL);
342
343 /* fork/exec a child */
344 tid = fork();
345 if (tid < 0)
346 err(1, "Fork failed\n");
347 if (tid == 0)
348 if (execvp(argv[optind - 1],
349 &argv[optind - 1]) < 0)
350 exit(-1);
351
352 /* Set the command type and avoid further processing */
353 cmd_type = TASKSTATS_CMD_ATTR_PID;
354 forking = 1;
355 break;
356 case 'v':
357 printf("debug on\n");
358 dbg = 1;
359 break;
360 case 'l':
361 printf("listen forever\n");
362 loop = 1;
363 break;
364 default:
365 usage();
366 exit(-1);
367 }
368 }
369
370 if (write_file) {
371 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
372 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
373 if (fd == -1) {
374 perror("Cannot open output file\n");
375 exit(1);
376 }
377 }
378
379 if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0)
380 err(1, "error creating Netlink socket\n");
381
382
383 mypid = getpid();
384 id = get_family_id(nl_sd);
385 if (!id) {
386 fprintf(stderr, "Error getting family id, errno %d\n", errno);
387 goto err;
388 }
389 PRINTF("family id %d\n", id);
390
391 if (maskset) {
392 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
393 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
394 &cpumask, strlen(cpumask) + 1);
395 PRINTF("Sent register cpumask, retval %d\n", rc);
396 if (rc < 0) {
397 fprintf(stderr, "error sending register cpumask\n");
398 goto err;
399 }
400 }
401
402 if (tid && containerset) {
403 fprintf(stderr, "Select either -t or -C, not both\n");
404 goto err;
405 }
406
407 /*
408 * If we forked a child, wait for it to exit. Cannot use waitpid()
409 * as all the delicious data would be reaped as part of the wait
410 */
411 if (tid && forking) {
412 int sig_received;
413 sigwait(&sigset, &sig_received);
414 }
415
416 if (tid) {
417 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
418 cmd_type, &tid, sizeof(__u32));
419 PRINTF("Sent pid/tgid, retval %d\n", rc);
420 if (rc < 0) {
421 fprintf(stderr, "error sending tid/tgid cmd\n");
422 goto done;
423 }
424 }
425
426 if (containerset) {
427 cfd = open(containerpath, O_RDONLY);
428 if (cfd < 0) {
429 perror("error opening container file");
430 goto err;
431 }
432 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,
433 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));
434 if (rc < 0) {
435 perror("error sending cgroupstats command");
436 goto err;
437 }
438 }
439 if (!maskset && !tid && !containerset) {
440 usage();
441 goto err;
442 }
443
444 do {
445 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
446 PRINTF("received %d bytes\n", rep_len);
447
448 if (rep_len < 0) {
449 fprintf(stderr, "nonfatal reply error: errno %d\n",
450 errno);
451 continue;
452 }
453 if (msg.n.nlmsg_type == NLMSG_ERROR ||
454 !NLMSG_OK((&msg.n), rep_len)) {
455 struct nlmsgerr *err = NLMSG_DATA(&msg);
456 fprintf(stderr, "fatal reply error, errno %d\n",
457 err->error);
458 goto done;
459 }
460
461 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
462 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
463
464
465 rep_len = GENLMSG_PAYLOAD(&msg.n);
466
467 na = (struct nlattr *) GENLMSG_DATA(&msg);
468 len = 0;
469 while (len < rep_len) {
470 len += NLA_ALIGN(na->nla_len);
471 switch (na->nla_type) {
472 case TASKSTATS_TYPE_AGGR_TGID:
473 /* Fall through */
474 case TASKSTATS_TYPE_AGGR_PID:
475 aggr_len = NLA_PAYLOAD(na->nla_len);
476 len2 = 0;
477 /* For nested attributes, na follows */
478 na = (struct nlattr *) NLA_DATA(na);
479 done = 0;
480 while (len2 < aggr_len) {
481 switch (na->nla_type) {
482 case TASKSTATS_TYPE_PID:
483 rtid = *(int *) NLA_DATA(na);
484 if (print_delays)
485 printf("PID\t%d\n", rtid);
486 break;
487 case TASKSTATS_TYPE_TGID:
488 rtid = *(int *) NLA_DATA(na);
489 if (print_delays)
490 printf("TGID\t%d\n", rtid);
491 break;
492 case TASKSTATS_TYPE_STATS:
493 count++;
494 if (print_delays)
495 print_delayacct((struct taskstats *) NLA_DATA(na));
496 if (print_io_accounting)
497 print_ioacct((struct taskstats *) NLA_DATA(na));
498 if (print_task_context_switch_counts)
499 task_context_switch_counts((struct taskstats *) NLA_DATA(na));
500 if (fd) {
501 if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
502 err(1,"write error\n");
503 }
504 }
505 if (!loop)
506 goto done;
507 break;
508 default:
509 fprintf(stderr, "Unknown nested"
510 " nla_type %d\n",
511 na->nla_type);
512 break;
513 }
514 len2 += NLA_ALIGN(na->nla_len);
515 na = (struct nlattr *) ((char *) na + len2);
516 }
517 break;
518
519 case CGROUPSTATS_TYPE_CGROUP_STATS:
520 print_cgroupstats(NLA_DATA(na));
521 break;
522 default:
523 fprintf(stderr, "Unknown nla_type %d\n",
524 na->nla_type);
525 case TASKSTATS_TYPE_NULL:
526 break;
527 }
528 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
529 }
530 } while (loop);
531 done:
532 if (maskset) {
533 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
534 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
535 &cpumask, strlen(cpumask) + 1);
536 printf("Sent deregister mask, retval %d\n", rc);
537 if (rc < 0)
538 err(rc, "error sending deregister cpumask\n");
539 }
540 err:
541 close(nl_sd);
542 if (fd)
543 close(fd);
544 if (cfd)
545 close(cfd);
546 return 0;
547 }
548