1 // SPDX-License-Identifier: GPL-2.0
2 /* getdelays.c
3 *
4 * Utility to get per-pid and per-tgid delay accounting statistics
5 * Also illustrates usage of the taskstats interface
6 *
7 * Copyright (C) Shailabh Nagar, IBM Corp. 2005
8 * Copyright (C) Balbir Singh, IBM Corp. 2006
9 * Copyright (c) Jay Lan, SGI. 2006
10 *
11 * Compile with
12 * gcc -I/usr/src/linux/include getdelays.c -o getdelays
13 */
14
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <errno.h>
18 #include <unistd.h>
19 #include <poll.h>
20 #include <string.h>
21 #include <fcntl.h>
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <sys/socket.h>
25 #include <sys/wait.h>
26 #include <signal.h>
27
28 #include <linux/genetlink.h>
29 #include <linux/taskstats.h>
30 #include <linux/cgroupstats.h>
31
32 /*
33 * Generic macros for dealing with netlink sockets. Might be duplicated
34 * elsewhere. It is recommended that commercial grade applications use
35 * libnl or libnetlink and use the interfaces provided by the library
36 */
37 #define GENLMSG_DATA(glh) ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN))
38 #define GENLMSG_PAYLOAD(glh) (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN)
39 #define NLA_DATA(na) ((void *)((char*)(na) + NLA_HDRLEN))
40 #define NLA_PAYLOAD(len) (len - NLA_HDRLEN)
41
42 #define err(code, fmt, arg...) \
43 do { \
44 fprintf(stderr, fmt, ##arg); \
45 exit(code); \
46 } while (0)
47
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
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 fprintf(stderr, " -C: container path\n");
83 }
84
85 /*
86 * Create a raw netlink socket and bind
87 */
88 static int create_nl_socket(int protocol)
89 {
90 int fd;
91 struct sockaddr_nl local;
92
93 fd = socket(AF_NETLINK, SOCK_RAW, protocol);
94 if (fd < 0)
95 return -1;
96
97 if (rcvbufsz)
98 if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
99 &rcvbufsz, sizeof(rcvbufsz)) < 0) {
100 fprintf(stderr, "Unable to set socket rcv buf size to %d\n",
101 rcvbufsz);
102 goto error;
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 static 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 + 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 static 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 = 0, 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 if (rc < 0)
179 return 0; /* sendto() failure? */
180
181 rep_len = recv(sd, &ans, sizeof(ans), 0);
182 if (ans.n.nlmsg_type == NLMSG_ERROR ||
183 (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
184 return 0;
185
186 na = (struct nlattr *) GENLMSG_DATA(&ans);
187 na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
188 if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
189 id = *(__u16 *) NLA_DATA(na);
190 }
191 return id;
192 }
193
194 #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1))
195
196 static void print_delayacct(struct taskstats *t)
197 {
198 printf("\n\nCPU %15s%15s%15s%15s%15s\n"
199 " %15llu%15llu%15llu%15llu%15.3fms\n"
200 "IO %15s%15s%15s\n"
201 " %15llu%15llu%15.3fms\n"
202 "SWAP %15s%15s%15s\n"
203 " %15llu%15llu%15.3fms\n"
204 "RECLAIM %12s%15s%15s\n"
205 " %15llu%15llu%15.3fms\n"
206 "THRASHING%12s%15s%15s\n"
207 " %15llu%15llu%15.3fms\n"
208 "COMPACT %12s%15s%15s\n"
209 " %15llu%15llu%15.3fms\n"
210 "WPCOPY %12s%15s%15s\n"
211 " %15llu%15llu%15.3fms\n"
212 "IRQ %15s%15s%15s\n"
213 " %15llu%15llu%15.3fms\n",
214 "count", "real total", "virtual total",
215 "delay total", "delay average",
216 (unsigned long long)t->cpu_count,
217 (unsigned long long)t->cpu_run_real_total,
218 (unsigned long long)t->cpu_run_virtual_total,
219 (unsigned long long)t->cpu_delay_total,
220 average_ms((double)t->cpu_delay_total, t->cpu_count),
221 "count", "delay total", "delay average",
222 (unsigned long long)t->blkio_count,
223 (unsigned long long)t->blkio_delay_total,
224 average_ms((double)t->blkio_delay_total, t->blkio_count),
225 "count", "delay total", "delay average",
226 (unsigned long long)t->swapin_count,
227 (unsigned long long)t->swapin_delay_total,
228 average_ms((double)t->swapin_delay_total, t->swapin_count),
229 "count", "delay total", "delay average",
230 (unsigned long long)t->freepages_count,
231 (unsigned long long)t->freepages_delay_total,
232 average_ms((double)t->freepages_delay_total, t->freepages_count),
233 "count", "delay total", "delay average",
234 (unsigned long long)t->thrashing_count,
235 (unsigned long long)t->thrashing_delay_total,
236 average_ms((double)t->thrashing_delay_total, t->thrashing_count),
237 "count", "delay total", "delay average",
238 (unsigned long long)t->compact_count,
239 (unsigned long long)t->compact_delay_total,
240 average_ms((double)t->compact_delay_total, t->compact_count),
241 "count", "delay total", "delay average",
242 (unsigned long long)t->wpcopy_count,
243 (unsigned long long)t->wpcopy_delay_total,
244 average_ms((double)t->wpcopy_delay_total, t->wpcopy_count),
245 "count", "delay total", "delay average",
246 (unsigned long long)t->irq_count,
247 (unsigned long long)t->irq_delay_total,
248 average_ms((double)t->irq_delay_total, t->irq_count));
249 }
250
251 static void task_context_switch_counts(struct taskstats *t)
252 {
253 printf("\n\nTask %15s%15s\n"
254 " %15llu%15llu\n",
255 "voluntary", "nonvoluntary",
256 (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);
257 }
258
259 static void print_cgroupstats(struct cgroupstats *c)
260 {
261 printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, "
262 "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,
263 (unsigned long long)c->nr_io_wait,
264 (unsigned long long)c->nr_running,
265 (unsigned long long)c->nr_stopped,
266 (unsigned long long)c->nr_uninterruptible);
267 }
268
269
270 static void print_ioacct(struct taskstats *t)
271 {
272 printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
273 t->ac_comm,
274 (unsigned long long)t->read_bytes,
275 (unsigned long long)t->write_bytes,
276 (unsigned long long)t->cancelled_write_bytes);
277 }
278
279 int main(int argc, char *argv[])
280 {
281 int c, rc, rep_len, aggr_len, len2;
282 int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;
283 __u16 id;
284 __u32 mypid;
285
286 struct nlattr *na;
287 int nl_sd = -1;
288 int len = 0;
289 pid_t tid = 0;
290 pid_t rtid = 0;
291
292 int fd = 0;
293 int write_file = 0;
294 int maskset = 0;
295 char *logfile = NULL;
296 int loop = 0;
297 int containerset = 0;
298 char *containerpath = NULL;
299 int cfd = 0;
300 int forking = 0;
301 sigset_t sigset;
302
303 struct msgtemplate msg;
304
305 while (!forking) {
306 c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
307 if (c < 0)
308 break;
309
310 switch (c) {
311 case 'd':
312 printf("print delayacct stats ON\n");
313 print_delays = 1;
314 break;
315 case 'i':
316 printf("printing IO accounting\n");
317 print_io_accounting = 1;
318 break;
319 case 'q':
320 printf("printing task/process context switch rates\n");
321 print_task_context_switch_counts = 1;
322 break;
323 case 'C':
324 containerset = 1;
325 containerpath = optarg;
326 break;
327 case 'w':
328 logfile = strdup(optarg);
329 printf("write to file %s\n", logfile);
330 write_file = 1;
331 break;
332 case 'r':
333 rcvbufsz = atoi(optarg);
334 printf("receive buf size %d\n", rcvbufsz);
335 if (rcvbufsz < 0)
336 err(1, "Invalid rcv buf size\n");
337 break;
338 case 'm':
339 strncpy(cpumask, optarg, sizeof(cpumask));
340 cpumask[sizeof(cpumask) - 1] = '\0';
341 maskset = 1;
342 printf("cpumask %s maskset %d\n", cpumask, maskset);
343 break;
344 case 't':
345 tid = atoi(optarg);
346 if (!tid)
347 err(1, "Invalid tgid\n");
348 cmd_type = TASKSTATS_CMD_ATTR_TGID;
349 break;
350 case 'p':
351 tid = atoi(optarg);
352 if (!tid)
353 err(1, "Invalid pid\n");
354 cmd_type = TASKSTATS_CMD_ATTR_PID;
355 break;
356 case 'c':
357
358 /* Block SIGCHLD for sigwait() later */
359 if (sigemptyset(&sigset) == -1)
360 err(1, "Failed to empty sigset");
361 if (sigaddset(&sigset, SIGCHLD))
362 err(1, "Failed to set sigchld in sigset");
363 sigprocmask(SIG_BLOCK, &sigset, NULL);
364
365 /* fork/exec a child */
366 tid = fork();
367 if (tid < 0)
368 err(1, "Fork failed\n");
369 if (tid == 0)
370 if (execvp(argv[optind - 1],
371 &argv[optind - 1]) < 0)
372 exit(-1);
373
374 /* Set the command type and avoid further processing */
375 cmd_type = TASKSTATS_CMD_ATTR_PID;
376 forking = 1;
377 break;
378 case 'v':
379 printf("debug on\n");
380 dbg = 1;
381 break;
382 case 'l':
383 printf("listen forever\n");
384 loop = 1;
385 break;
386 default:
387 usage();
388 exit(-1);
389 }
390 }
391
392 if (write_file) {
393 fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
394 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
395 if (fd == -1) {
396 perror("Cannot open output file\n");
397 exit(1);
398 }
399 }
400
401 nl_sd = create_nl_socket(NETLINK_GENERIC);
402 if (nl_sd < 0)
403 err(1, "error creating Netlink socket\n");
404
405
406 mypid = getpid();
407 id = get_family_id(nl_sd);
408 if (!id) {
409 fprintf(stderr, "Error getting family id, errno %d\n", errno);
410 goto err;
411 }
412 PRINTF("family id %d\n", id);
413
414 if (maskset) {
415 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
416 TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
417 &cpumask, strlen(cpumask) + 1);
418 PRINTF("Sent register cpumask, retval %d\n", rc);
419 if (rc < 0) {
420 fprintf(stderr, "error sending register cpumask\n");
421 goto err;
422 }
423 }
424
425 if (tid && containerset) {
426 fprintf(stderr, "Select either -t or -C, not both\n");
427 goto err;
428 }
429
430 /*
431 * If we forked a child, wait for it to exit. Cannot use waitpid()
432 * as all the delicious data would be reaped as part of the wait
433 */
434 if (tid && forking) {
435 int sig_received;
436 sigwait(&sigset, &sig_received);
437 }
438
439 if (tid) {
440 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
441 cmd_type, &tid, sizeof(__u32));
442 PRINTF("Sent pid/tgid, retval %d\n", rc);
443 if (rc < 0) {
444 fprintf(stderr, "error sending tid/tgid cmd\n");
445 goto done;
446 }
447 }
448
449 if (containerset) {
450 cfd = open(containerpath, O_RDONLY);
451 if (cfd < 0) {
452 perror("error opening container file");
453 goto err;
454 }
455 rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,
456 CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));
457 if (rc < 0) {
458 perror("error sending cgroupstats command");
459 goto err;
460 }
461 }
462 if (!maskset && !tid && !containerset) {
463 usage();
464 goto err;
465 }
466
467 do {
468 rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
469 PRINTF("received %d bytes\n", rep_len);
470
471 if (rep_len < 0) {
472 fprintf(stderr, "nonfatal reply error: errno %d\n",
473 errno);
474 continue;
475 }
476 if (msg.n.nlmsg_type == NLMSG_ERROR ||
477 !NLMSG_OK((&msg.n), rep_len)) {
478 struct nlmsgerr *err = NLMSG_DATA(&msg);
479 fprintf(stderr, "fatal reply error, errno %d\n",
480 err->error);
481 goto done;
482 }
483
484 PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
485 sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
486
487
488 rep_len = GENLMSG_PAYLOAD(&msg.n);
489
490 na = (struct nlattr *) GENLMSG_DATA(&msg);
491 len = 0;
492 while (len < rep_len) {
493 len += NLA_ALIGN(na->nla_len);
494 switch (na->nla_type) {
495 case TASKSTATS_TYPE_AGGR_TGID:
496 /* Fall through */
497 case TASKSTATS_TYPE_AGGR_PID:
498 aggr_len = NLA_PAYLOAD(na->nla_len);
499 len2 = 0;
500 /* For nested attributes, na follows */
501 na = (struct nlattr *) NLA_DATA(na);
502 while (len2 < aggr_len) {
503 switch (na->nla_type) {
504 case TASKSTATS_TYPE_PID:
505 rtid = *(int *) NLA_DATA(na);
506 if (print_delays)
507 printf("PID\t%d\n", rtid);
508 break;
509 case TASKSTATS_TYPE_TGID:
510 rtid = *(int *) NLA_DATA(na);
511 if (print_delays)
512 printf("TGID\t%d\n", rtid);
513 break;
514 case TASKSTATS_TYPE_STATS:
515 if (print_delays)
516 print_delayacct((struct taskstats *) NLA_DATA(na));
517 if (print_io_accounting)
518 print_ioacct((struct taskstats *) NLA_DATA(na));
519 if (print_task_context_switch_counts)
520 task_context_switch_counts((struct taskstats *) NLA_DATA(na));
521 if (fd) {
522 if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
523 err(1,"write error\n");
524 }
525 }
526 if (!loop)
527 goto done;
528 break;
529 case TASKSTATS_TYPE_NULL:
530 break;
531 default:
532 fprintf(stderr, "Unknown nested"
533 " nla_type %d\n",
534 na->nla_type);
535 break;
536 }
537 len2 += NLA_ALIGN(na->nla_len);
538 na = (struct nlattr *)((char *)na +
539 NLA_ALIGN(na->nla_len));
540 }
541 break;
542
543 case CGROUPSTATS_TYPE_CGROUP_STATS:
544 print_cgroupstats(NLA_DATA(na));
545 break;
546 default:
547 fprintf(stderr, "Unknown nla_type %d\n",
548 na->nla_type);
549 case TASKSTATS_TYPE_NULL:
550 break;
551 }
552 na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
553 }
554 } while (loop);
555 done:
556 if (maskset) {
557 rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
558 TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
559 &cpumask, strlen(cpumask) + 1);
560 printf("Sent deregister mask, retval %d\n", rc);
561 if (rc < 0)
562 err(rc, "error sending deregister cpumask\n");
563 }
564 err:
565 close(nl_sd);
566 if (fd)
567 close(fd);
568 if (cfd)
569 close(cfd);
570 return 0;
571 }
572
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