xref: /linux/tools/accounting/procacct.c (revision e2683c8868d03382da7e1ce8453b543a043066d1)
1 // SPDX-License-Identifier: GPL-2.0
2 /* procacct.c
3  *
4  * Demonstrator of fetching resource data on task exit, as a way
5  * to accumulate accurate program resource usage statistics, without
6  * prior identification of the programs. For that, the fields for
7  * device and inode of the program executable binary file are also
8  * extracted in addition to the command string.
9  *
10  * The TGID together with the PID and the AGROUP flag allow
11  * identification of threads in a process and single-threaded processes.
12  * The ac_tgetime field gives proper whole-process walltime.
13  *
14  * Written (changed) by Thomas Orgis, University of Hamburg in 2022
15  *
16  * This is a cheap derivation (inheriting the style) of getdelays.c:
17  *
18  * Utility to get per-pid and per-tgid delay accounting statistics
19  * Also illustrates usage of the taskstats interface
20  *
21  * Copyright (C) Shailabh Nagar, IBM Corp. 2005
22  * Copyright (C) Balbir Singh, IBM Corp. 2006
23  * Copyright (c) Jay Lan, SGI. 2006
24  */
25 
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <poll.h>
31 #include <string.h>
32 #include <fcntl.h>
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <sys/socket.h>
36 #include <sys/wait.h>
37 #include <signal.h>
38 
39 #include <linux/genetlink.h>
40 #include <linux/acct.h>
41 #include <linux/taskstats.h>
42 #include <linux/kdev_t.h>
43 
44 /*
45  * Generic macros for dealing with netlink sockets. Might be duplicated
46  * elsewhere. It is recommended that commercial grade applications use
47  * libnl or libnetlink and use the interfaces provided by the library
48  */
49 #define GENLMSG_DATA(glh)	((void *)(NLMSG_DATA(glh) + GENL_HDRLEN))
50 #define GENLMSG_PAYLOAD(glh)	(NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN)
51 #define NLA_DATA(na)		((void *)((char *)(na) + NLA_HDRLEN))
52 #define NLA_PAYLOAD(len)	(len - NLA_HDRLEN)
53 
54 #define err(code, fmt, arg...)			\
55 	do {					\
56 		fprintf(stderr, fmt, ##arg);	\
57 		exit(code);			\
58 	} while (0)
59 
60 int rcvbufsz;
61 char name[100];
62 int dbg;
63 int print_delays;
64 int print_io_accounting;
65 int print_task_context_switch_counts;
66 
67 #define PRINTF(fmt, arg...) {			\
68 		if (dbg) {			\
69 			printf(fmt, ##arg);	\
70 		}				\
71 	}
72 
73 /* Maximum size of response requested or message sent */
74 #define MAX_MSG_SIZE	2048
75 /* Maximum number of cpus expected to be specified in a cpumask */
76 #define MAX_CPUS	32
77 
78 struct msgtemplate {
79 	struct nlmsghdr n;
80 	struct genlmsghdr g;
81 	char buf[MAX_MSG_SIZE];
82 };
83 
84 char cpumask[100+6*MAX_CPUS];
85 
86 static void usage(void)
87 {
88 	fprintf(stderr, "procacct [-v] [-w logfile] [-r bufsize] [-m cpumask]\n");
89 	fprintf(stderr, "  -v: debug on\n");
90 }
91 
92 /*
93  * Create a raw netlink socket and bind
94  */
95 static int create_nl_socket(int protocol)
96 {
97 	int fd;
98 	struct sockaddr_nl local;
99 
100 	fd = socket(AF_NETLINK, SOCK_RAW, protocol);
101 	if (fd < 0)
102 		return -1;
103 
104 	if (rcvbufsz)
105 		if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
106 				&rcvbufsz, sizeof(rcvbufsz)) < 0) {
107 			fprintf(stderr, "Unable to set socket rcv buf size to %d\n",
108 				rcvbufsz);
109 			goto error;
110 		}
111 
112 	memset(&local, 0, sizeof(local));
113 	local.nl_family = AF_NETLINK;
114 
115 	if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
116 		goto error;
117 
118 	return fd;
119 error:
120 	close(fd);
121 	return -1;
122 }
123 
124 static int recv_taskstats_msg(int sd, struct msgtemplate *msg)
125 {
126 	struct sockaddr_nl nladdr;
127 	struct iovec iov = {
128 		.iov_base = msg,
129 		.iov_len = sizeof(*msg),
130 	};
131 	struct msghdr hdr = {
132 		.msg_name = &nladdr,
133 		.msg_namelen = sizeof(nladdr),
134 		.msg_iov = &iov,
135 		.msg_iovlen = 1,
136 	};
137 	int ret;
138 
139 	ret = recvmsg(sd, &hdr, 0);
140 	if (ret < 0)
141 		return -1;
142 	if (hdr.msg_flags & MSG_TRUNC) {
143 		errno = EMSGSIZE;
144 		return -1;
145 	}
146 
147 	return ret;
148 }
149 
150 
151 static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid,
152 	     __u8 genl_cmd, __u16 nla_type,
153 	     void *nla_data, int nla_len)
154 {
155 	struct nlattr *na;
156 	struct sockaddr_nl nladdr;
157 	int r, buflen;
158 	char *buf;
159 
160 	struct msgtemplate msg;
161 
162 	msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
163 	msg.n.nlmsg_type = nlmsg_type;
164 	msg.n.nlmsg_flags = NLM_F_REQUEST;
165 	msg.n.nlmsg_seq = 0;
166 	msg.n.nlmsg_pid = nlmsg_pid;
167 	msg.g.cmd = genl_cmd;
168 	msg.g.version = 0x1;
169 	na = (struct nlattr *) GENLMSG_DATA(&msg);
170 	na->nla_type = nla_type;
171 	na->nla_len = nla_len + 1 + NLA_HDRLEN;
172 	memcpy(NLA_DATA(na), nla_data, nla_len);
173 	msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len);
174 
175 	buf = (char *) &msg;
176 	buflen = msg.n.nlmsg_len;
177 	memset(&nladdr, 0, sizeof(nladdr));
178 	nladdr.nl_family = AF_NETLINK;
179 	while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr,
180 			   sizeof(nladdr))) < buflen) {
181 		if (r > 0) {
182 			buf += r;
183 			buflen -= r;
184 		} else if (errno != EAGAIN)
185 			return -1;
186 	}
187 	return 0;
188 }
189 
190 
191 /*
192  * Probe the controller in genetlink to find the family id
193  * for the TASKSTATS family
194  */
195 static int get_family_id(int sd)
196 {
197 	struct {
198 		struct nlmsghdr n;
199 		struct genlmsghdr g;
200 		char buf[256];
201 	} ans;
202 
203 	int id = 0, rc;
204 	struct nlattr *na;
205 	int rep_len;
206 
207 	strcpy(name, TASKSTATS_GENL_NAME);
208 	rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
209 			CTRL_ATTR_FAMILY_NAME, (void *)name,
210 			strlen(TASKSTATS_GENL_NAME)+1);
211 	if (rc < 0)
212 		return 0;	/* sendto() failure? */
213 
214 	rep_len = recv(sd, &ans, sizeof(ans), 0);
215 	if (ans.n.nlmsg_type == NLMSG_ERROR ||
216 	    (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
217 		return 0;
218 
219 	na = (struct nlattr *) GENLMSG_DATA(&ans);
220 	na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
221 	if (na->nla_type == CTRL_ATTR_FAMILY_ID)
222 		id = *(__u16 *) NLA_DATA(na);
223 
224 	return id;
225 }
226 
227 #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1))
228 
229 static void print_procacct(struct taskstats *t)
230 {
231 	/* First letter: T is a mere thread, G the last in a group, U  unknown. */
232 	printf(
233 		"%c pid=%lu tgid=%lu uid=%lu wall=%llu gwall=%llu cpu=%llu vmpeak=%llu rsspeak=%llu dev=%lu:%lu inode=%llu comm=%s\n"
234 	,	t->version >= 12 ? (t->ac_flag & AGROUP ? 'P' : 'T') : '?'
235 	,	(unsigned long)t->ac_pid
236 	,	(unsigned long)(t->version >= 12 ? t->ac_tgid : 0)
237 	,	(unsigned long)t->ac_uid
238 	,	(unsigned long long)t->ac_etime
239 	,	(unsigned long long)(t->version >= 12 ? t->ac_tgetime : 0)
240 	,	(unsigned long long)(t->ac_utime+t->ac_stime)
241 	,	(unsigned long long)t->hiwater_vm
242 	,	(unsigned long long)t->hiwater_rss
243 	,	(unsigned long)(t->version >= 12 ? MAJOR(t->ac_exe_dev) : 0)
244 	,	(unsigned long)(t->version >= 12 ? MINOR(t->ac_exe_dev) : 0)
245 	,	(unsigned long long)(t->version >= 12 ? t->ac_exe_inode : 0)
246 	,	t->ac_comm
247 	);
248 }
249 
250 void handle_aggr(int mother, struct nlattr *na, int fd)
251 {
252 	int aggr_len = NLA_PAYLOAD(na->nla_len);
253 	int len2 = 0;
254 	pid_t rtid = 0;
255 
256 	na = (struct nlattr *) NLA_DATA(na);
257 	while (len2 < aggr_len) {
258 		switch (na->nla_type) {
259 		case TASKSTATS_TYPE_PID:
260 			rtid = *(int *) NLA_DATA(na);
261 			PRINTF("PID\t%d\n", rtid);
262 			break;
263 		case TASKSTATS_TYPE_TGID:
264 			rtid = *(int *) NLA_DATA(na);
265 			PRINTF("TGID\t%d\n", rtid);
266 			break;
267 		case TASKSTATS_TYPE_STATS:
268 			PRINTF("version %u\n",
269 			       ((struct taskstats *)NLA_DATA(na))->version);
270 			if (mother == TASKSTATS_TYPE_AGGR_PID)
271 				print_procacct((struct taskstats *) NLA_DATA(na));
272 			if (fd) {
273 				if (write(fd, NLA_DATA(na), na->nla_len) < 0)
274 					err(1, "write error\n");
275 			}
276 			break;
277 		case TASKSTATS_TYPE_NULL:
278 			break;
279 		default:
280 			fprintf(stderr, "Unknown nested nla_type %d\n",
281 				na->nla_type);
282 			break;
283 		}
284 		len2 += NLA_ALIGN(na->nla_len);
285 		na = (struct nlattr *)((char *)na +
286 						 NLA_ALIGN(na->nla_len));
287 	}
288 }
289 
290 int main(int argc, char *argv[])
291 {
292 	int c, rc, rep_len;
293 	__u16 id;
294 	__u32 mypid;
295 
296 	struct nlattr *na;
297 	int nl_sd = -1;
298 	int len = 0;
299 
300 	int fd = 0;
301 	int write_file = 0;
302 	int maskset = 0;
303 	char *logfile = NULL;
304 	int cfd = 0;
305 
306 	struct msgtemplate msg;
307 
308 	while (1) {
309 		c = getopt(argc, argv, "m:vr:w:");
310 		if (c < 0)
311 			break;
312 
313 		switch (c) {
314 		case 'w':
315 			logfile = strdup(optarg);
316 			printf("write to file %s\n", logfile);
317 			write_file = 1;
318 			break;
319 		case 'r':
320 			rcvbufsz = atoi(optarg);
321 			printf("receive buf size %d\n", rcvbufsz);
322 			if (rcvbufsz < 0)
323 				err(1, "Invalid rcv buf size\n");
324 			break;
325 		case 'm':
326 			strncpy(cpumask, optarg, sizeof(cpumask));
327 			cpumask[sizeof(cpumask) - 1] = '\0';
328 			maskset = 1;
329 			break;
330 		case 'v':
331 			printf("debug on\n");
332 			dbg = 1;
333 			break;
334 		default:
335 			usage();
336 			exit(-1);
337 		}
338 	}
339 	if (!maskset) {
340 		maskset = 1;
341 		strncpy(cpumask, "1", sizeof(cpumask));
342 		cpumask[sizeof(cpumask) - 1] = '\0';
343 	}
344 	printf("cpumask %s maskset %d\n", cpumask, maskset);
345 
346 	if (write_file) {
347 		fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
348 		if (fd == -1) {
349 			perror("Cannot open output file\n");
350 			exit(1);
351 		}
352 	}
353 
354 	nl_sd = create_nl_socket(NETLINK_GENERIC);
355 	if (nl_sd < 0)
356 		err(1, "error creating Netlink socket\n");
357 
358 	mypid = getpid();
359 	id = get_family_id(nl_sd);
360 	if (!id) {
361 		fprintf(stderr, "Error getting family id, errno %d\n", errno);
362 		goto err;
363 	}
364 	PRINTF("family id %d\n", id);
365 
366 	if (maskset) {
367 		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
368 			      TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
369 			      &cpumask, strlen(cpumask) + 1);
370 		PRINTF("Sent register cpumask, retval %d\n", rc);
371 		if (rc < 0) {
372 			fprintf(stderr, "error sending register cpumask\n");
373 			goto err;
374 		}
375 	}
376 
377 	do {
378 		rep_len = recv_taskstats_msg(nl_sd, &msg);
379 		PRINTF("received %d bytes\n", rep_len);
380 
381 		if (rep_len < 0) {
382 			if (errno == EMSGSIZE)
383 				fprintf(stderr,
384 					"dropped truncated taskstats netlink message, please increase MAX_MSG_SIZE\n");
385 			else
386 				fprintf(stderr, "nonfatal reply error: errno %d\n",
387 					errno);
388 			continue;
389 		}
390 		if (msg.n.nlmsg_type == NLMSG_ERROR ||
391 		    !NLMSG_OK((&msg.n), rep_len)) {
392 			struct nlmsgerr *err = NLMSG_DATA(&msg);
393 
394 			fprintf(stderr, "fatal reply error,  errno %d\n",
395 				err->error);
396 			goto done;
397 		}
398 
399 		PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
400 		       sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
401 
402 
403 		rep_len = GENLMSG_PAYLOAD(&msg.n);
404 
405 		na = (struct nlattr *) GENLMSG_DATA(&msg);
406 		len = 0;
407 		while (len < rep_len) {
408 			len += NLA_ALIGN(na->nla_len);
409 			int mother = na->nla_type;
410 
411 			PRINTF("mother=%i\n", mother);
412 			switch (na->nla_type) {
413 			case TASKSTATS_TYPE_AGGR_PID:
414 			case TASKSTATS_TYPE_AGGR_TGID:
415 				/* For nested attributes, na follows */
416 				handle_aggr(mother, na, fd);
417 				break;
418 			default:
419 				fprintf(stderr, "Unexpected nla_type %d\n",
420 					na->nla_type);
421 			case TASKSTATS_TYPE_NULL:
422 				break;
423 			}
424 			na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
425 		}
426 	} while (1);
427 done:
428 	if (maskset) {
429 		rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
430 			      TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
431 			      &cpumask, strlen(cpumask) + 1);
432 		printf("Sent deregister mask, retval %d\n", rc);
433 		if (rc < 0)
434 			err(rc, "error sending deregister cpumask\n");
435 	}
436 err:
437 	close(nl_sd);
438 	if (fd)
439 		close(fd);
440 	if (cfd)
441 		close(cfd);
442 	return 0;
443 }
444