busybox/init/bootchartd.c

452 lines
13 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//applet:IF_BOOTCHARTD(APPLET(bootchartd, BB_DIR_SBIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_BOOTCHARTD) += bootchartd.o
//config:config BOOTCHARTD
//config: bool "bootchartd"
//config: default y
//config: help
//config: bootchartd is commonly used to profile the boot process
//config: for the purpose of speeding it up. In this case, it is started
//config: by the kernel as the init process. This is configured by adding
//config: the init=/sbin/bootchartd option to the kernel command line.
//config:
//config: It can also be used to monitor the resource usage of a specific
//config: application or the running system in general. In this case,
//config: bootchartd is started interactively by running bootchartd start
//config: and stopped using bootchartd stop.
//config:
//config:config FEATURE_BOOTCHARTD_BLOATED_HEADER
//config: bool "Compatible, bloated header"
//config: default y
//config: depends on BOOTCHARTD
//config: help
//config: Create extended header file compatible with "big" bootchartd.
//config: "Big" bootchartd is a shell script and it dumps some
//config: "convenient" info int the header, such as:
//config: title = Boot chart for `hostname` (`date`)
//config: system.uname = `uname -srvm`
//config: system.release = `cat /etc/DISTRO-release`
//config: system.cpu = `grep '^model name' /proc/cpuinfo | head -1` ($cpucount)
//config: system.kernel.options = `cat /proc/cmdline`
//config: This data is not mandatory for bootchart graph generation,
//config: and is considered bloat. Nevertheless, this option
//config: makes bootchartd applet to dump a subset of it.
//config:
//config:config FEATURE_BOOTCHARTD_CONFIG_FILE
//config: bool "Support bootchartd.conf"
//config: default y
//config: depends on BOOTCHARTD
//config: help
//config: Enable reading and parsing of $PWD/bootchartd.conf
//config: and /etc/bootchartd.conf files.
#include "libbb.h"
/* After libbb.h, since it needs sys/types.h on some systems */
#include <sys/utsname.h>
#ifdef __linux__
# include <sys/mount.h>
# ifndef MS_SILENT
# define MS_SILENT (1 << 15)
# endif
# ifndef MNT_DETACH
# define MNT_DETACH 0x00000002
# endif
#endif
#define BC_VERSION_STR "0.8"
/* For debugging, set to 0:
* strace won't work with DO_SIGNAL_SYNC set to 1.
*/
#define DO_SIGNAL_SYNC 1
//$PWD/bootchartd.conf and /etc/bootchartd.conf:
//supported options:
//# Sampling period (in seconds)
//SAMPLE_PERIOD=0.2
//
//not yet supported:
//# tmpfs size
//# (32 MB should suffice for ~20 minutes worth of log data, but YMMV)
//TMPFS_SIZE=32m
//
//# Whether to enable and store BSD process accounting information. The
//# kernel needs to be configured to enable v3 accounting
//# (CONFIG_BSD_PROCESS_ACCT_V3). accton from the GNU accounting utilities
//# is also required.
//PROCESS_ACCOUNTING="no"
//
//# Tarball for the various boot log files
//BOOTLOG_DEST=/var/log/bootchart.tgz
//
//# Whether to automatically stop logging as the boot process completes.
//# The logger will look for known processes that indicate bootup completion
//# at a specific runlevel (e.g. gdm-binary, mingetty, etc.).
//AUTO_STOP_LOGGER="yes"
//
//# Whether to automatically generate the boot chart once the boot logger
//# completes. The boot chart will be generated in $AUTO_RENDER_DIR.
//# Note that the bootchart package must be installed.
//AUTO_RENDER="no"
//
//# Image format to use for the auto-generated boot chart
//# (choose between png, svg and eps).
//AUTO_RENDER_FORMAT="png"
//
//# Output directory for auto-generated boot charts
//AUTO_RENDER_DIR="/var/log"
/* Globals */
struct globals {
char jiffy_line[COMMON_BUFSIZE];
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
static void dump_file(FILE *fp, const char *filename)
{
int fd = open(filename, O_RDONLY);
if (fd >= 0) {
fputs(G.jiffy_line, fp);
fflush(fp);
bb_copyfd_eof(fd, fileno(fp));
close(fd);
fputc('\n', fp);
}
}
static int dump_procs(FILE *fp, int look_for_login_process)
{
struct dirent *entry;
DIR *dir = opendir("/proc");
int found_login_process = 0;
fputs(G.jiffy_line, fp);
while ((entry = readdir(dir)) != NULL) {
char name[sizeof("/proc/%u/cmdline") + sizeof(int)*3];
int stat_fd;
unsigned pid = bb_strtou(entry->d_name, NULL, 10);
if (errno)
continue;
/* Android's version reads /proc/PID/cmdline and extracts
* non-truncated process name. Do we want to do that? */
sprintf(name, "/proc/%u/stat", pid);
stat_fd = open(name, O_RDONLY);
if (stat_fd >= 0) {
char *p;
char stat_line[4*1024];
int rd = safe_read(stat_fd, stat_line, sizeof(stat_line)-2);
close(stat_fd);
if (rd < 0)
continue;
stat_line[rd] = '\0';
p = strchrnul(stat_line, '\n');
*p++ = '\n';
*p = '\0';
fputs(stat_line, fp);
if (!look_for_login_process)
continue;
p = strchr(stat_line, '(');
if (!p)
continue;
p++;
strchrnul(p, ')')[0] = '\0';
/* Is it gdm, kdm or a getty? */
if (((p[0] == 'g' || p[0] == 'k' || p[0] == 'x') && p[1] == 'd' && p[2] == 'm')
|| strstr(p, "getty")
) {
found_login_process = 1;
}
}
}
closedir(dir);
fputc('\n', fp);
return found_login_process;
}
static char *make_tempdir(void)
{
char template[] = "/tmp/bootchart.XXXXXX";
char *tempdir = xstrdup(mkdtemp(template));
if (!tempdir) {
#ifdef __linux__
/* /tmp is not writable (happens when we are used as init).
* Try to mount a tmpfs, them cd and lazily unmount it.
* Since we unmount it at once, we can mount it anywhere.
* Try a few locations which are likely ti exist.
*/
static const char dirs[] = "/mnt\0""/tmp\0""/boot\0""/proc\0";
const char *try_dir = dirs;
while (mount("none", try_dir, "tmpfs", MS_SILENT, "size=16m") != 0) {
try_dir += strlen(try_dir) + 1;
if (!try_dir[0])
bb_perror_msg_and_die("can't %smount tmpfs", "");
}
//bb_error_msg("mounted tmpfs on %s", try_dir);
xchdir(try_dir);
if (umount2(try_dir, MNT_DETACH) != 0) {
bb_perror_msg_and_die("can't %smount tmpfs", "un");
}
#else
bb_perror_msg_and_die("can't create temporary directory");
#endif
} else {
xchdir(tempdir);
}
return tempdir;
}
static void do_logging(unsigned sample_period_us)
{
//# Enable process accounting if configured
//if [ "$PROCESS_ACCOUNTING" = "yes" ]; then
// [ -e kernel_pacct ] || : > kernel_pacct
// accton kernel_pacct
//fi
FILE *proc_stat = xfopen("proc_stat.log", "w");
FILE *proc_diskstats = xfopen("proc_diskstats.log", "w");
//FILE *proc_netdev = xfopen("proc_netdev.log", "w");
FILE *proc_ps = xfopen("proc_ps.log", "w");
int look_for_login_process = (getppid() == 1);
unsigned count = 60*1000*1000 / sample_period_us; /* ~1 minute */
while (--count && !bb_got_signal) {
char *p;
int len = open_read_close("/proc/uptime", G.jiffy_line, sizeof(G.jiffy_line)-2);
if (len < 0)
goto wait_more;
/* /proc/uptime has format "NNNNNN.MM NNNNNNN.MM" */
/* we convert it to "NNNNNNMM\n" (using first value) */
G.jiffy_line[len] = '\0';
p = strchr(G.jiffy_line, '.');
if (!p)
goto wait_more;
while (isdigit(*++p))
p[-1] = *p;
p[-1] = '\n';
p[0] = '\0';
dump_file(proc_stat, "/proc/stat");
dump_file(proc_diskstats, "/proc/diskstats");
//dump_file(proc_netdev, "/proc/net/dev");
if (dump_procs(proc_ps, look_for_login_process)) {
/* dump_procs saw a getty or {g,k,x}dm
* stop logging in 2 seconds:
*/
if (count > 2*1000*1000 / sample_period_us)
count = 2*1000*1000 / sample_period_us;
}
fflush_all();
wait_more:
usleep(sample_period_us);
}
// [ -e kernel_pacct ] && accton off
}
static void finalize(char *tempdir, const char *prog)
{
//# Stop process accounting if configured
//local pacct=
//[ -e kernel_pacct ] && pacct=kernel_pacct
FILE *header_fp = xfopen("header", "w");
if (prog)
fprintf(header_fp, "profile.process = %s\n", prog);
fputs("version = "BC_VERSION_STR"\n", header_fp);
if (ENABLE_FEATURE_BOOTCHARTD_BLOATED_HEADER) {
char *hostname;
char *kcmdline;
time_t t;
struct tm tm_time;
/* x2 for possible localized weekday/month names */
char date_buf[sizeof("Mon Jun 21 05:29:03 CEST 2010") * 2];
struct utsname unamebuf;
hostname = safe_gethostname();
time(&t);
localtime_r(&t, &tm_time);
strftime(date_buf, sizeof(date_buf), "%a %b %e %H:%M:%S %Z %Y", &tm_time);
fprintf(header_fp, "title = Boot chart for %s (%s)\n", hostname, date_buf);
if (ENABLE_FEATURE_CLEAN_UP)
free(hostname);
uname(&unamebuf); /* never fails */
/* same as uname -srvm */
fprintf(header_fp, "system.uname = %s %s %s %s\n",
unamebuf.sysname,
unamebuf.release,
unamebuf.version,
unamebuf.machine
);
//system.release = `cat /etc/DISTRO-release`
//system.cpu = `grep '^model name' /proc/cpuinfo | head -1` ($cpucount)
kcmdline = xmalloc_open_read_close("/proc/cmdline", NULL);
/* kcmdline includes trailing "\n" */
fprintf(header_fp, "system.kernel.options = %s", kcmdline);
if (ENABLE_FEATURE_CLEAN_UP)
free(kcmdline);
}
fclose(header_fp);
/* Package log files */
system("tar -zcf /var/log/bootchart.tgz header *.log"); // + $pacct
/* Clean up (if we are not in detached tmpfs) */
if (tempdir) {
unlink("header");
unlink("proc_stat.log");
unlink("proc_diskstats.log");
//unlink("proc_netdev.log");
unlink("proc_ps.log");
rmdir(tempdir);
}
/* shell-based bootchartd tries to run /usr/bin/bootchart if $AUTO_RENDER=yes:
* /usr/bin/bootchart -o "$AUTO_RENDER_DIR" -f $AUTO_RENDER_FORMAT "$BOOTLOG_DEST"
*/
}
//usage:#define bootchartd_trivial_usage
//usage: "start [PROG ARGS]|stop|init"
//usage:#define bootchartd_full_usage "\n\n"
//usage: "Create /var/log/bootchart.tgz with boot chart data\n"
//usage: "\nstart: start background logging; with PROG, run PROG, then kill logging with USR1"
//usage: "\nstop: send USR1 to all bootchartd processes"
//usage: "\ninit: start background logging; stop when getty/xdm is seen (for init scripts)"
//usage: "\nUnder PID 1: as init, then exec $bootchart_init, /init, /sbin/init"
int bootchartd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int bootchartd_main(int argc UNUSED_PARAM, char **argv)
{
unsigned sample_period_us;
pid_t parent_pid, logger_pid;
smallint cmd;
enum {
CMD_STOP = 0,
CMD_START,
CMD_INIT,
CMD_PID1, /* used to mark pid 1 case */
};
INIT_G();
parent_pid = getpid();
if (argv[1]) {
cmd = index_in_strings("stop\0""start\0""init\0", argv[1]);
if (cmd < 0)
bb_show_usage();
if (cmd == CMD_STOP) {
pid_t *pidList = find_pid_by_name("bootchartd");
while (*pidList != 0) {
if (*pidList != parent_pid)
kill(*pidList, SIGUSR1);
pidList++;
}
return EXIT_SUCCESS;
}
} else {
if (parent_pid != 1)
bb_show_usage();
cmd = CMD_PID1;
}
/* Here we are in START, INIT or CMD_PID1 state */
/* Read config file: */
sample_period_us = 200 * 1000;
if (ENABLE_FEATURE_BOOTCHARTD_CONFIG_FILE) {
char* token[2];
parser_t *parser = config_open2("/etc/bootchartd.conf" + 5, fopen_for_read);
if (!parser)
parser = config_open2("/etc/bootchartd.conf", fopen_for_read);
while (config_read(parser, token, 2, 0, "#=", PARSE_NORMAL & ~PARSE_COLLAPSE)) {
if (strcmp(token[0], "SAMPLE_PERIOD") == 0 && token[1])
sample_period_us = atof(token[1]) * 1000000;
}
config_close(parser);
}
if ((int)sample_period_us <= 0)
sample_period_us = 1; /* prevent division by 0 */
/* Create logger child: */
logger_pid = fork_or_rexec(argv);
if (logger_pid == 0) { /* child */
char *tempdir;
bb_signals(0
+ (1 << SIGUSR1)
+ (1 << SIGUSR2)
+ (1 << SIGTERM)
+ (1 << SIGQUIT)
+ (1 << SIGINT)
+ (1 << SIGHUP)
, record_signo);
if (DO_SIGNAL_SYNC)
/* Inform parent that we are ready */
raise(SIGSTOP);
/* If we are started by kernel, PATH might be unset.
* In order to find "tar", let's set some sane PATH:
*/
if (cmd == CMD_PID1 && !getenv("PATH"))
putenv((char*)bb_PATH_root_path);
tempdir = make_tempdir();
do_logging(sample_period_us);
finalize(tempdir, cmd == CMD_START ? argv[2] : NULL);
return EXIT_SUCCESS;
}
/* parent */
if (DO_SIGNAL_SYNC) {
/* Wait for logger child to set handlers, then unpause it.
* Otherwise with short-lived PROG (e.g. "bootchartd start true")
* we might send SIGUSR1 before logger sets its handler.
*/
waitpid(logger_pid, NULL, WUNTRACED);
kill(logger_pid, SIGCONT);
}
if (cmd == CMD_PID1) {
char *bootchart_init = getenv("bootchart_init");
if (bootchart_init)
execl(bootchart_init, bootchart_init, NULL);
execl("/init", "init", NULL);
execl("/sbin/init", "init", NULL);
bb_perror_msg_and_die("can't execute '%s'", "/sbin/init");
}
if (cmd == CMD_START && argv[2]) { /* "start PROG ARGS" */
pid_t pid = xvfork();
if (pid == 0) { /* child */
argv += 2;
BB_EXECVP_or_die(argv);
}
/* parent */
waitpid(pid, NULL, 0);
kill(logger_pid, SIGUSR1);
}
return EXIT_SUCCESS;
}