aboutsummaryrefslogtreecommitdiff
path: root/Documentation/accounting/getdelays.c
blob: e9c77788a39d8f2c5c807b59295be6c3f1b3fea6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
/* getdelays.c
 *
 * Utility to get per-pid and per-tgid delay accounting statistics
 * Also illustrates usage of the taskstats interface
 *
 * Copyright (C) Shailabh Nagar, IBM Corp. 2005
 * Copyright (C) Balbir Singh, IBM Corp. 2006
 * Copyright (c) Jay Lan, SGI. 2006
 *
 * Compile with
 *	gcc -I/usr/src/linux/include getdelays.c -o getdelays
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <poll.h>
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <signal.h>

#include <linux/genetlink.h>
#include <linux/taskstats.h>
#include <linux/cgroupstats.h>

/*
 * Generic macros for dealing with netlink sockets. Might be duplicated
 * elsewhere. It is recommended that commercial grade applications use
 * libnl or libnetlink and use the interfaces provided by the library
 */
#define GENLMSG_DATA(glh)	((void *)(NLMSG_DATA(glh) + GENL_HDRLEN))
#define GENLMSG_PAYLOAD(glh)	(NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN)
#define NLA_DATA(na)		((void *)((char*)(na) + NLA_HDRLEN))
#define NLA_PAYLOAD(len)	(len - NLA_HDRLEN)

#define err(code, fmt, arg...)			\
	do {					\
		fprintf(stderr, fmt, ##arg);	\
		exit(code);			\
	} while (0)

int done;
int rcvbufsz;
char name[100];
int dbg;
int print_delays;
int print_io_accounting;
int print_task_context_switch_counts;
__u64 stime, utime;

#define PRINTF(fmt, arg...) {			\
	    if (dbg) {				\
		printf(fmt, ##arg);		\
	    }					\
	}

/* Maximum size of response requested or message sent */
#define MAX_MSG_SIZE	1024
/* Maximum number of cpus expected to be specified in a cpumask */
#define MAX_CPUS	32

struct msgtemplate {
	struct nlmsghdr n;
	struct genlmsghdr g;
	char buf[MAX_MSG_SIZE];
};

char cpumask[100+6*MAX_CPUS];

static void usage(void)
{
	fprintf(stderr, "getdelays [-dilv] [-w logfile] [-r bufsize] "
			"[-m cpumask] [-t tgid] [-p pid]\n");
	fprintf(stderr, "  -d: print delayacct stats\n");
	fprintf(stderr, "  -i: print IO accounting (works only with -p)\n");
	fprintf(stderr, "  -l: listen forever\n");
	fprintf(stderr, "  -v: debug on\n");
	fprintf(stderr, "  -C: container path\n");
}

/*
 * Create a raw netlink socket and bind
 */
static int create_nl_socket(int protocol)
{
	int fd;
	struct sockaddr_nl local;

	fd = socket(AF_NETLINK, SOCK_RAW, protocol);
	if (fd < 0)
		return -1;

	if (rcvbufsz)
		if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
				&rcvbufsz, sizeof(rcvbufsz)) < 0) {
			fprintf(stderr, "Unable to set socket rcv buf size "
					"to %d\n",
				rcvbufsz);
			return -1;
		}

	memset(&local, 0, sizeof(local));
	local.nl_family = AF_NETLINK;

	if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
		goto error;

	return fd;
error:
	close(fd);
	return -1;
}


static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid,
	     __u8 genl_cmd, __u16 nla_type,
	     void *nla_data, int nla_len)
{
	struct nlattr *na;
	struct sockaddr_nl nladdr;
	int r, buflen;
	char *buf;

	struct msgtemplate msg;

	msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
	msg.n.nlmsg_type = nlmsg_type;
	msg.n.nlmsg_flags = NLM_F_REQUEST;
	msg.n.nlmsg_seq = 0;
	msg.n.nlmsg_pid = nlmsg_pid;
	msg.g.cmd = genl_cmd;
	msg.g.version = 0x1;
	na = (struct nlattr *) GENLMSG_DATA(&msg);
	na->nla_type = nla_type;
	na->nla_len = nla_len + 1 + NLA_HDRLEN;
	memcpy(NLA_DATA(na), nla_data, nla_len);
	msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len);

	buf = (char *) &msg;
	buflen = msg.n.nlmsg_len ;
	memset(&nladdr, 0, sizeof(nladdr));
	nladdr.nl_family = AF_NETLINK;
	while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr,
			   sizeof(nladdr))) < buflen) {
		if (r > 0) {
			buf += r;
			buflen -= r;
		} else if (errno != EAGAIN)
			return -1;
	}
	return 0;
}


/*
 * Probe the controller in genetlink to find the family id
 * for the TASKSTATS family
 */
static int get_family_id(int sd)
{
	struct {
		struct nlmsghdr n;
		struct genlmsghdr g;
		char buf[256];
	} ans;

	int id = 0, rc;
	struct nlattr *na;
	int rep_len;

	strcpy(name, TASKSTATS_GENL_NAME);
	rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
			CTRL_ATTR_FAMILY_NAME, (void *)name,
			strlen(TASKSTATS_GENL_NAME)+1);

	rep_len = recv(sd, &ans, sizeof(ans), 0);
	if (ans.n.nlmsg_type == NLMSG_ERROR ||
	    (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
		return 0;

	na = (struct nlattr *) GENLMSG_DATA(&ans);
	na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
	if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
		id = *(__u16 *) NLA_DATA(na);
	}
	return id;
}

static void print_delayacct(struct taskstats *t)
{
	printf("\n\nCPU   %15s%15s%15s%15s\n"
	       "      %15llu%15llu%15llu%15llu\n"
	       "IO    %15s%15s\n"
	       "      %15llu%15llu\n"
	       "SWAP  %15s%15s\n"
	       "      %15llu%15llu\n"
	       "RECLAIM  %12s%15s\n"
	       "      %15llu%15llu\n",
	       "count", "real total", "virtual total", "delay total",
	       (unsigned long long)t->cpu_count,
	       (unsigned long long)t->cpu_run_real_total,
	       (unsigned long long)t->cpu_run_virtual_total,
	       (unsigned long long)t->cpu_delay_total,
	       "count", "delay total",
	       (unsigned long long)t->blkio_count,
	       (unsigned long long)t->blkio_delay_total,
	       "count", "delay total",
	       (unsigned long long)t->swapin_count,
	       (unsigned long long)t->swapin_delay_total,
	       "count", "delay total",
	       (unsigned long long)t->freepages_count,
	       (unsigned long long)t->freepages_delay_total);
}

static void task_context_switch_counts(struct taskstats *t)
{
	printf("\n\nTask   %15s%15s\n"
	       "       %15llu%15llu\n",
	       "voluntary", "nonvoluntary",
	       (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);
}

static void print_cgroupstats(struct cgroupstats *c)
{
	printf("sleeping %llu, blocked %llu, running %llu, stopped %llu, "
		"uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,
		(unsigned long long)c->nr_io_wait,
		(unsigned long long)c->nr_running,
		(unsigned long long)c->nr_stopped,
		(unsigned long long)c->nr_uninterruptible);
}


static void print_ioacct(struct taskstats *t)
{
	printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n",
		t->ac_comm,
		(unsigned long long)t->read_bytes,
		(unsigned long long)t->write_bytes,
		(unsigned long long)t->cancelled_write_bytes);
}

int main(int argc, char *argv[])
{
	int c, rc, rep_len, aggr_len, len2;
	int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;
	__u16 id;
	__u32 mypid;

	struct nlattr *na;
	int nl_sd = -1;
	int len = 0;
	pid_t tid = 0;
	pid_t rtid = 0;

	int fd = 0;
	int count = 0;
	int write_file = 0;
	int maskset = 0;
	char *logfile = NULL;
	int loop = 0;
	int containerset = 0;
	char containerpath[1024];
	int cfd = 0;
	int forking = 0;
	sigset_t sigset;

	struct msgtemplate msg;

	while (!forking) {
		c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
		if (c < 0)
			break;

		switch (c) {
		case 'd':
			printf("print delayacct stats ON\n");
			print_delays = 1;
			break;
		case 'i':
			printf("printing IO accounting\n");
			print_io_accounting = 1;
			break;
		case 'q':
			printf("printing task/process context switch rates\n");
			print_task_context_switch_counts = 1;
			break;
		case 'C':
			containerset = 1;
			strncpy(containerpath, optarg, strlen(optarg) + 1);
			break;
		case 'w':
			logfile = strdup(optarg);
			printf("write to file %s\n", logfile);
			write_file = 1;
			break;
		case 'r':
			rcvbufsz = atoi(optarg);
			printf("receive buf size %d\n", rcvbufsz);
			if (rcvbufsz < 0)
				err(1, "Invalid rcv buf size\n");
			break;
		case 'm':
			strncpy(cpumask, optarg, sizeof(cpumask));
			maskset = 1;
			printf("cpumask %s maskset %d\n", cpumask, maskset);
			break;
		case 't':
			tid = atoi(optarg);
			if (!tid)
				err(1, "Invalid tgid\n");
			cmd_type = TASKSTATS_CMD_ATTR_TGID;
			break;
		case 'p':
			tid = atoi(optarg);
			if (!tid)
				err(1, "Invalid pid\n");
			cmd_type = TASKSTATS_CMD_ATTR_PID;
			break;
		case 'c':

			/* Block SIGCHLD for sigwait() later */
			if (sigemptyset(&sigset) == -1)
				err(1, "Failed to empty sigset");
			if (sigaddset(&sigset, SIGCHLD))
				err(1, "Failed to set sigchld in sigset");
			sigprocmask(SIG_BLOCK, &sigset, NULL);

			/* fork/exec a child */
			tid = fork();
			if (tid < 0)
				err(1, "Fork failed\n");
			if (tid == 0)
				if (execvp(argv[optind - 1],
				    &argv[optind - 1]) < 0)
					exit(-1);

			/* Set the command type and avoid further processing */
			cmd_type = TASKSTATS_CMD_ATTR_PID;
			forking = 1;
			break;
		case 'v':
			printf("debug on\n");
			dbg = 1;
			break;
		case 'l':
			printf("listen forever\n");
			loop = 1;
			break;
		default:
			usage();
			exit(-1);
		}
	}

	if (write_file) {
		fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
			  S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
		if (fd == -1) {
			perror("Cannot open output file\n");
			exit(1);
		}
	}

	if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0)
		err(1, "error creating Netlink socket\n");


	mypid = getpid();
	id = get_family_id(nl_sd);
	if (!id) {
		fprintf(stderr, "Error getting family id, errno %d\n", errno);
		goto err;
	}
	PRINTF("family id %d\n", id);

	if (maskset) {
		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
			      TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
			      &cpumask, strlen(cpumask) + 1);
		PRINTF("Sent register cpumask, retval %d\n", rc);
		if (rc < 0) {
			fprintf(stderr, "error sending register cpumask\n");
			goto err;
		}
	}

	if (tid && containerset) {
		fprintf(stderr, "Select either -t or -C, not both\n");
		goto err;
	}

	/*
	 * If we forked a child, wait for it to exit. Cannot use waitpid()
	 * as all the delicious data would be reaped as part of the wait
	 */
	if (tid && forking) {
		int sig_received;
		sigwait(&sigset, &sig_received);
	}

	if (tid) {
		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
			      cmd_type, &tid, sizeof(__u32));
		PRINTF("Sent pid/tgid, retval %d\n", rc);
		if (rc < 0) {
			fprintf(stderr, "error sending tid/tgid cmd\n");
			goto done;
		}
	}

	if (containerset) {
		cfd = open(containerpath, O_RDONLY);
		if (cfd < 0) {
			perror("error opening container file");
			goto err;
		}
		rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,
			      CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));
		if (rc < 0) {
			perror("error sending cgroupstats command");
			goto err;
		}
	}
	if (!maskset && !tid && !containerset) {
		usage();
		goto err;
	}

	do {
		int i;

		rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
		PRINTF("received %d bytes\n", rep_len);

		if (rep_len < 0) {
			fprintf(stderr, "nonfatal reply error: errno %d\n",
				errno);
			continue;
		}
		if (msg.n.nlmsg_type == NLMSG_ERROR ||
		    !NLMSG_OK((&msg.n), rep_len)) {
			struct nlmsgerr *err = NLMSG_DATA(&msg);
			fprintf(stderr, "fatal reply error,  errno %d\n",
				err->error);
			goto done;
		}

		PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
		       sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);


		rep_len = GENLMSG_PAYLOAD(&msg.n);

		na = (struct nlattr *) GENLMSG_DATA(&msg);
		len = 0;
		i = 0;
		while (len < rep_len) {
			len += NLA_ALIGN(na->nla_len);
			switch (na->nla_type) {
			case TASKSTATS_TYPE_AGGR_TGID:
				/* Fall through */
			case TASKSTATS_TYPE_AGGR_PID:
				aggr_len = NLA_PAYLOAD(na->nla_len);
				len2 = 0;
				/* For nested attributes, na follows */
				na = (struct nlattr *) NLA_DATA(na);
				done = 0;
				while (len2 < aggr_len) {
					switch (na->nla_type) {
					case TASKSTATS_TYPE_PID:
						rtid = *(int *) NLA_DATA(na);
						if (print_delays)
							printf("PID\t%d\n", rtid);
						break;
					case TASKSTATS_TYPE_TGID:
						rtid = *(int *) NLA_DATA(na);
						if (print_delays)
							printf("TGID\t%d\n", rtid);
						break;
					case TASKSTATS_TYPE_STATS:
						count++;
						if (print_delays)
							print_delayacct((struct taskstats *) NLA_DATA(na));
						if (print_io_accounting)
							print_ioacct((struct taskstats *) NLA_DATA(na));
						if (print_task_context_switch_counts)
							task_context_switch_counts((struct taskstats *) NLA_DATA(na));
						if (fd) {
							if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
								err(1,"write error\n");
							}
						}
						if (!loop)
							goto done;
						break;
					default:
						fprintf(stderr, "Unknown nested"
							" nla_type %d\n",
							na->nla_type);
						break;
					}
					len2 += NLA_ALIGN(na->nla_len);
					na = (struct nlattr *) ((char *) na + len2);
				}
				break;

			case CGROUPSTATS_TYPE_CGROUP_STATS:
				print_cgroupstats(NLA_DATA(na));
				break;
			default:
				fprintf(stderr, "Unknown nla_type %d\n",
					na->nla_type);
			case TASKSTATS_TYPE_NULL:
				break;
			}
			na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
		}
	} while (loop);
done:
	if (maskset) {
		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
			      TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
			      &cpumask, strlen(cpumask) + 1);
		printf("Sent deregister mask, retval %d\n", rc);
		if (rc < 0)
			err(rc, "error sending deregister cpumask\n");
	}
err:
	close(nl_sd);
	if (fd)
		close(fd);
	if (cfd)
		close(cfd);
	return 0;
}