xref: /linux/tools/accounting/getdelays.c (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
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