init/bootchartd.c

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