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