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 //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
 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')
 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
 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
 219 static void do_logging(unsigned sample_period_us, int process_accounting)
 220 {
 221         FILE *proc_stat = xfopen("proc_stat.log", "w");
 222         FILE *proc_diskstats = xfopen("proc_diskstats.log", "w");
 223         //FILE *proc_netdev = xfopen("proc_netdev.log", "w");
 224         FILE *proc_ps = xfopen("proc_ps.log", "w");
 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
 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("header", "w");
 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;
 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 }