1 /* vi: set sw=4 ts=4: */
2 /*
3  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
4  */
5 //config:config BOOTCHARTD
6 //config:	bool "bootchartd (10 kb)"
7 //config:	default y
8 //config:	help
9 //config:	bootchartd is commonly used to profile the boot process
10 //config:	for the purpose of speeding it up. In this case, it is started
11 //config:	by the kernel as the init process. This is configured by adding
12 //config:	the init=/sbin/bootchartd option to the kernel command line.
13 //config:
14 //config:	It can also be used to monitor the resource usage of a specific
15 //config:	application or the running system in general. In this case,
16 //config:	bootchartd is started interactively by running bootchartd start
17 //config:	and stopped using bootchartd stop.
18 //config:
19 //config:config FEATURE_BOOTCHARTD_BLOATED_HEADER
20 //config:	bool "Compatible, bloated header"
21 //config:	default y
22 //config:	depends on BOOTCHARTD
23 //config:	help
24 //config:	Create extended header file compatible with "big" bootchartd.
25 //config:	"Big" bootchartd is a shell script and it dumps some
26 //config:	"convenient" info into the header, such as:
27 //config:		title = Boot chart for `hostname` (`date`)
28 //config:		system.uname = `uname -srvm`
29 //config:		system.release = `cat /etc/DISTRO-release`
30 //config:		system.cpu = `grep '^model name' /proc/cpuinfo | head -1` ($cpucount)
31 //config:		system.kernel.options = `cat /proc/cmdline`
32 //config:	This data is not mandatory for bootchart graph generation,
33 //config:	and is considered bloat. Nevertheless, this option
34 //config:	makes bootchartd applet to dump a subset of it.
35 //config:
36 //config:config FEATURE_BOOTCHARTD_CONFIG_FILE
37 //config:	bool "Support bootchartd.conf"
38 //config:	default y
39 //config:	depends on BOOTCHARTD
40 //config:	help
41 //config:	Enable reading and parsing of $PWD/bootchartd.conf
42 //config:	and /etc/bootchartd.conf files.
43 
44 //applet:IF_BOOTCHARTD(APPLET(bootchartd, BB_DIR_SBIN, BB_SUID_DROP))
45 
46 //kbuild:lib-$(CONFIG_BOOTCHARTD) += bootchartd.o
47 
48 #include "libbb.h"
49 #include "common_bufsiz.h"
50 /* After libbb.h, since it needs sys/types.h on some systems */
51 #include <sys/utsname.h>
52 
53 #ifdef __linux__
54 # include <sys/mount.h>
55 # ifndef MS_SILENT
56 #  define MS_SILENT      (1 << 15)
57 # endif
58 # ifndef MNT_DETACH
59 #  define MNT_DETACH 0x00000002
60 # endif
61 #endif
62 
63 #if !ENABLE_TAR && !ENABLE_WERROR
64 # warning Note: bootchartd requires tar command, but you did not select it.
65 #elif !ENABLE_FEATURE_SEAMLESS_GZ && !ENABLE_WERROR
66 # warning Note: bootchartd requires tar -z support, but you did not select it.
67 #endif
68 
69 #define BC_VERSION_STR "0.8"
70 
71 /* For debugging, set to 0:
72  * strace won't work with DO_SIGNAL_SYNC set to 1.
73  */
74 #define DO_SIGNAL_SYNC 1
75 
76 
77 //$PWD/bootchartd.conf and /etc/bootchartd.conf:
78 //supported options:
79 //# Sampling period (in seconds)
80 //SAMPLE_PERIOD=0.2
81 //
82 //not yet supported:
83 //# tmpfs size
84 //# (32 MB should suffice for ~20 minutes worth of log data, but YMMV)
85 //TMPFS_SIZE=32m
86 //
87 //# Whether to enable and store BSD process accounting information.  The
88 //# kernel needs to be configured to enable v3 accounting
89 //# (CONFIG_BSD_PROCESS_ACCT_V3). accton from the GNU accounting utilities
90 //# is also required.
91 //PROCESS_ACCOUNTING="no"
92 //
93 //# Tarball for the various boot log files
94 //BOOTLOG_DEST=/var/log/bootchart.tgz
95 //
96 //# Whether to automatically stop logging as the boot process completes.
97 //# The logger will look for known processes that indicate bootup completion
98 //# at a specific runlevel (e.g. gdm-binary, mingetty, etc.).
99 //AUTO_STOP_LOGGER="yes"
100 //
101 //# Whether to automatically generate the boot chart once the boot logger
102 //# completes.  The boot chart will be generated in $AUTO_RENDER_DIR.
103 //# Note that the bootchart package must be installed.
104 //AUTO_RENDER="no"
105 //
106 //# Image format to use for the auto-generated boot chart
107 //# (choose between png, svg and eps).
108 //AUTO_RENDER_FORMAT="png"
109 //
110 //# Output directory for auto-generated boot charts
111 //AUTO_RENDER_DIR="/var/log"
112 
113 
114 /* Globals */
115 struct globals {
116 	char jiffy_line[COMMON_BUFSIZE];
117 } FIX_ALIASING;
118 #define G (*(struct globals*)bb_common_bufsiz1)
119 #define INIT_G() do { setup_common_bufsiz(); } while (0)
120 
dump_file(FILE * fp,const char * filename)121 static void dump_file(FILE *fp, const char *filename)
122 {
123 	int fd = open(filename, O_RDONLY);
124 	if (fd >= 0) {
125 		fputs(G.jiffy_line, fp);
126 		fflush(fp);
127 		bb_copyfd_eof(fd, fileno(fp));
128 		close(fd);
129 		fputc('\n', fp);
130 	}
131 }
132 
dump_procs(FILE * fp,int look_for_login_process)133 static int dump_procs(FILE *fp, int look_for_login_process)
134 {
135 	struct dirent *entry;
136 	DIR *dir = opendir("/proc");
137 	int found_login_process = 0;
138 
139 	fputs(G.jiffy_line, fp);
140 	while ((entry = readdir(dir)) != NULL) {
141 		char name[sizeof("/proc/%u/cmdline") + sizeof(int)*3];
142 		int stat_fd;
143 		unsigned pid = bb_strtou(entry->d_name, NULL, 10);
144 		if (errno)
145 			continue;
146 
147 		/* Android's version reads /proc/PID/cmdline and extracts
148 		 * non-truncated process name. Do we want to do that? */
149 
150 		sprintf(name, "/proc/%u/stat", pid);
151 		stat_fd = open(name, O_RDONLY);
152 		if (stat_fd >= 0) {
153 			char *p;
154 			char stat_line[4*1024];
155 			int rd = safe_read(stat_fd, stat_line, sizeof(stat_line)-2);
156 
157 			close(stat_fd);
158 			if (rd < 0)
159 				continue;
160 			stat_line[rd] = '\0';
161 			p = strchrnul(stat_line, '\n');
162 			*p++ = '\n';
163 			*p = '\0';
164 			fputs(stat_line, fp);
165 			if (!look_for_login_process)
166 				continue;
167 			p = strchr(stat_line, '(');
168 			if (!p)
169 				continue;
170 			p++;
171 			strchrnul(p, ')')[0] = '\0';
172 			/* Is it gdm, kdm or a getty? */
173 			if (((p[0] == 'g' || p[0] == 'k' || p[0] == 'x')
174 			     && p[1] == 'd' && p[2] == 'm' && p[3] == '\0'
175 			    )
176 			 || strstr(p, "getty")
177 			) {
178 				found_login_process = 1;
179 			}
180 		}
181 	}
182 	closedir(dir);
183 	fputc('\n', fp);
184 	return found_login_process;
185 }
186 
make_tempdir(void)187 static char *make_tempdir(void)
188 {
189 	char template[] = "/tmp/bootchart.XXXXXX";
190 	char *tempdir = xstrdup(mkdtemp(template));
191 	if (!tempdir) {
192 #ifdef __linux__
193 		/* /tmp is not writable (happens when we are used as init).
194 		 * Try to mount a tmpfs, then cd and lazily unmount it.
195 		 * Since we unmount it at once, we can mount it anywhere.
196 		 * Try a few locations which are likely ti exist.
197 		 */
198 		static const char dirs[] ALIGN1 = "/mnt\0""/tmp\0""/boot\0""/proc\0";
199 		const char *try_dir = dirs;
200 		while (mount("none", try_dir, "tmpfs", MS_SILENT, "size=16m") != 0) {
201 			try_dir += strlen(try_dir) + 1;
202 			if (!try_dir[0])
203 				bb_perror_msg_and_die("can't %smount tmpfs", "");
204 		}
205 		//bb_error_msg("mounted tmpfs on %s", try_dir);
206 		xchdir(try_dir);
207 		if (umount2(try_dir, MNT_DETACH) != 0) {
208 			bb_perror_msg_and_die("can't %smount tmpfs", "un");
209 		}
210 #else
211 		bb_simple_perror_msg_and_die("can't create temporary directory");
212 #endif
213 	} else {
214 		xchdir(tempdir);
215 	}
216 	return tempdir;
217 }
218 
do_logging(unsigned sample_period_us,int process_accounting)219 static void do_logging(unsigned sample_period_us, int process_accounting)
220 {
221 	FILE *proc_stat = xfopen_for_write("proc_stat.log");
222 	FILE *proc_diskstats = xfopen_for_write("proc_diskstats.log");
223 	//FILE *proc_netdev = xfopen_for_write("proc_netdev.log");
224 	FILE *proc_ps = xfopen_for_write("proc_ps.log");
225 	int look_for_login_process = (getppid() == 1);
226 	unsigned count = 60*1000*1000 / sample_period_us; /* ~1 minute */
227 
228 	if (process_accounting) {
229 		close(xopen("kernel_pacct", O_WRONLY | O_CREAT | O_TRUNC));
230 		acct("kernel_pacct");
231 	}
232 
233 	while (--count && !bb_got_signal) {
234 		char *p;
235 		int len = open_read_close("/proc/uptime", G.jiffy_line, sizeof(G.jiffy_line)-2);
236 		if (len < 0)
237 			goto wait_more;
238 		/* /proc/uptime has format "NNNNNN.MM NNNNNNN.MM" */
239 		/* we convert it to "NNNNNNMM\n" (using first value) */
240 		G.jiffy_line[len] = '\0';
241 		p = strchr(G.jiffy_line, '.');
242 		if (!p)
243 			goto wait_more;
244 		while (isdigit(*++p))
245 			p[-1] = *p;
246 		p[-1] = '\n';
247 		p[0] = '\0';
248 
249 		dump_file(proc_stat, "/proc/stat");
250 		dump_file(proc_diskstats, "/proc/diskstats");
251 		//dump_file(proc_netdev, "/proc/net/dev");
252 		if (dump_procs(proc_ps, look_for_login_process)) {
253 			/* dump_procs saw a getty or {g,k,x}dm
254 			 * stop logging in 2 seconds:
255 			 */
256 			if (count > 2*1000*1000 / sample_period_us)
257 				count = 2*1000*1000 / sample_period_us;
258 		}
259 		fflush_all();
260  wait_more:
261 		usleep(sample_period_us);
262 	}
263 }
264 
finalize(char * tempdir,const char * prog,int process_accounting)265 static void finalize(char *tempdir, const char *prog, int process_accounting)
266 {
267 	//# Stop process accounting if configured
268 	//local pacct=
269 	//[ -e kernel_pacct ] && pacct=kernel_pacct
270 
271 	FILE *header_fp = xfopen_for_write("header");
272 
273 	if (process_accounting)
274 		acct(NULL);
275 
276 	if (prog)
277 		fprintf(header_fp, "profile.process = %s\n", prog);
278 
279 	fputs("version = "BC_VERSION_STR"\n", header_fp);
280 	if (ENABLE_FEATURE_BOOTCHARTD_BLOATED_HEADER) {
281 		char *hostname;
282 		char *kcmdline;
283 		time_t t;
284 		struct tm tm_time;
285 		/* x2 for possible localized weekday/month names */
286 		char date_buf[sizeof("Mon Jun 21 05:29:03 CEST 2010") * 2];
287 		struct utsname unamebuf;
288 
289 		hostname = safe_gethostname();
290 		time(&t);
291 		localtime_r(&t, &tm_time);
292 		strftime(date_buf, sizeof(date_buf), "%a %b %e %H:%M:%S %Z %Y", &tm_time);
293 		fprintf(header_fp, "title = Boot chart for %s (%s)\n", hostname, date_buf);
294 		if (ENABLE_FEATURE_CLEAN_UP)
295 			free(hostname);
296 
297 		uname(&unamebuf); /* never fails */
298 		/* same as uname -srvm */
299 		fprintf(header_fp, "system.uname = %s %s %s %s\n",
300 				unamebuf.sysname,
301 				unamebuf.release,
302 				unamebuf.version,
303 				unamebuf.machine
304 		);
305 
306 		//system.release = `cat /etc/DISTRO-release`
307 		//system.cpu = `grep '^model name' /proc/cpuinfo | head -1` ($cpucount)
308 
309 		kcmdline = xmalloc_open_read_close("/proc/cmdline", NULL);
310 		/* kcmdline includes trailing "\n" */
311 		fprintf(header_fp, "system.kernel.options = %s", kcmdline);
312 		if (ENABLE_FEATURE_CLEAN_UP)
313 			free(kcmdline);
314 	}
315 	fclose(header_fp);
316 
317 	/* Package log files */
318 	system(xasprintf("tar -zcf /var/log/bootlog.tgz header %s *.log", process_accounting ? "kernel_pacct" : ""));
319 	/* Clean up (if we are not in detached tmpfs) */
320 	if (tempdir) {
321 		unlink("header");
322 		unlink("proc_stat.log");
323 		unlink("proc_diskstats.log");
324 		//unlink("proc_netdev.log");
325 		unlink("proc_ps.log");
326 		if (process_accounting)
327 			unlink("kernel_pacct");
328 		rmdir(tempdir);
329 	}
330 
331 	/* shell-based bootchartd tries to run /usr/bin/bootchart if $AUTO_RENDER=yes:
332 	 * /usr/bin/bootchart -o "$AUTO_RENDER_DIR" -f $AUTO_RENDER_FORMAT "$BOOTLOG_DEST"
333 	 */
334 }
335 
336 //usage:#define bootchartd_trivial_usage
337 //usage:       "start [PROG ARGS]|stop|init"
338 //usage:#define bootchartd_full_usage "\n\n"
339 //usage:       "Create /var/log/bootchart.tgz with boot chart data\n"
340 //usage:     "\nstart: start background logging; with PROG, run PROG, then kill logging with USR1"
341 //usage:     "\nstop: send USR1 to all bootchartd processes"
342 //usage:     "\ninit: start background logging; stop when getty/xdm is seen (for init scripts)"
343 //usage:     "\nUnder PID 1: as init, then exec $bootchart_init, /init, /sbin/init"
344 
345 int bootchartd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
bootchartd_main(int argc UNUSED_PARAM,char ** argv)346 int bootchartd_main(int argc UNUSED_PARAM, char **argv)
347 {
348 	unsigned sample_period_us;
349 	pid_t parent_pid, logger_pid;
350 	smallint cmd;
351 	int process_accounting;
352 	enum {
353 		CMD_STOP = 0,
354 		CMD_START,
355 		CMD_INIT,
356 		CMD_PID1, /* used to mark pid 1 case */
357 	};
358 
359 	INIT_G();
360 
361 	parent_pid = getpid();
362 	if (argv[1]) {
363 		cmd = index_in_strings("stop\0""start\0""init\0", argv[1]);
364 		if (cmd < 0)
365 			bb_show_usage();
366 		if (cmd == CMD_STOP) {
367 			pid_t *pidList = find_pid_by_name("bootchartd");
368 			while (*pidList != 0) {
369 				if (*pidList != parent_pid)
370 					kill(*pidList, SIGUSR1);
371 				pidList++;
372 			}
373 			return EXIT_SUCCESS;
374 		}
375 	} else {
376 		if (parent_pid != 1)
377 			bb_show_usage();
378 		cmd = CMD_PID1;
379 	}
380 
381 	/* Here we are in START, INIT or CMD_PID1 state */
382 
383 	/* Read config file: */
384 	sample_period_us = 200 * 1000;
385 	process_accounting = 0;
386 	if (ENABLE_FEATURE_BOOTCHARTD_CONFIG_FILE) {
387 		char* token[2];
388 		parser_t *parser = config_open2("/etc/bootchartd.conf" + 5, fopen_for_read);
389 		if (!parser)
390 			parser = config_open2("/etc/bootchartd.conf", fopen_for_read);
391 		while (config_read(parser, token, 2, 0, "#=", PARSE_NORMAL & ~PARSE_COLLAPSE)) {
392 			if (strcmp(token[0], "SAMPLE_PERIOD") == 0 && token[1])
393 				sample_period_us = atof(token[1]) * 1000000;
394 			if (strcmp(token[0], "PROCESS_ACCOUNTING") == 0 && token[1]
395 			 && (strcmp(token[1], "on") == 0 || strcmp(token[1], "yes") == 0)
396 			) {
397 				process_accounting = 1;
398 			}
399 		}
400 		config_close(parser);
401 		if ((int)sample_period_us <= 0)
402 			sample_period_us = 1; /* prevent division by 0 */
403 	}
404 
405 	/* Create logger child: */
406 	logger_pid = fork_or_rexec(argv);
407 
408 	if (logger_pid == 0) { /* child */
409 		char *tempdir;
410 
411 		bb_signals(0
412 			+ (1 << SIGUSR1)
413 			+ (1 << SIGUSR2)
414 			+ (1 << SIGTERM)
415 			+ (1 << SIGQUIT)
416 			+ (1 << SIGINT)
417 			+ (1 << SIGHUP)
418 			, record_signo);
419 
420 		if (DO_SIGNAL_SYNC)
421 			/* Inform parent that we are ready */
422 			raise(SIGSTOP);
423 
424 		/* If we are started by kernel, PATH might be unset.
425 		 * In order to find "tar", let's set some sane PATH:
426 		 */
427 		if (cmd == CMD_PID1 && !getenv("PATH"))
428 			putenv((char*)bb_PATH_root_path);
429 
430 		tempdir = make_tempdir();
431 		do_logging(sample_period_us, process_accounting);
432 		finalize(tempdir, cmd == CMD_START ? argv[2] : NULL, process_accounting);
433 		return EXIT_SUCCESS;
434 	}
435 
436 	/* parent */
437 
438 	USE_FOR_NOMMU(argv[0][0] &= 0x7f); /* undo fork_or_rexec() damage */
439 
440 	if (DO_SIGNAL_SYNC) {
441 		/* Wait for logger child to set handlers, then unpause it.
442 		 * Otherwise with short-lived PROG (e.g. "bootchartd start true")
443 		 * we might send SIGUSR1 before logger sets its handler.
444 		 */
445 		waitpid(logger_pid, NULL, WUNTRACED);
446 		kill(logger_pid, SIGCONT);
447 	}
448 
449 	if (cmd == CMD_PID1) {
450 		char *bootchart_init = getenv("bootchart_init");
451 		if (bootchart_init)
452 			execl(bootchart_init, bootchart_init, NULL);
453 		execl("/init", "init", NULL);
454 		execl("/sbin/init", "init", NULL);
455 		bb_perror_msg_and_die("can't execute '%s'", "/sbin/init");
456 	}
457 
458 	if (cmd == CMD_START && argv[2]) { /* "start PROG ARGS" */
459 		pid_t pid = xvfork();
460 		if (pid == 0) { /* child */
461 			argv += 2;
462 			BB_EXECVP_or_die(argv);
463 		}
464 		/* parent */
465 		waitpid(pid, NULL, 0);
466 		kill(logger_pid, SIGUSR1);
467 	}
468 
469 	return EXIT_SUCCESS;
470 }
471