#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <fcntl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
-#include <fcntl.h>
#include <sys/sysinfo.h>
#include <sys/stat.h>
/* global variables*/
static int udevsendsock;
+static pid_t sid;
static int pipefds[2];
static long startup_time;
/* child */
close(udevsendsock);
logging_close();
+
+ setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
execve(udev_bin, argv, msg->envp);
dbg("exec of child failed");
_exit(1);
case -1:
dbg("fork of child failed");
run_queue_delete(msg);
- /* note: we never managed to run, so we had no impact on
- * running_with_devpath(), so don't bother setting run_exec_q
- */
break;
default:
/* get SIGCHLD in main loop */
}
}
+static int running_processes(void)
+{
+ int f;
+ static char buf[4096];
+ int len;
+ int running;
+ const char *pos;
+
+ f = open("/proc/stat", O_RDONLY);
+ if (f == -1)
+ return -1;
+
+ len = read(f, buf, sizeof(buf));
+ close(f);
+
+ if (len <= 0)
+ return -1;
+ else
+ buf[len] = '\0';
+
+ pos = strstr(buf, "procs_running ");
+ if (pos == NULL)
+ return -1;
+
+ if (sscanf(pos, "procs_running %u", &running) != 1)
+ return -1;
+
+ return running;
+}
+
+/* return the number of process es in our session, count only until limit */
+static int running_processes_in_session(pid_t session, int limit)
+{
+ DIR *dir;
+ struct dirent *dent;
+ int running = 0;
+
+ dir = opendir("/proc");
+ if (!dir)
+ return -1;
+
+ /* read process info from /proc */
+ for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+ int f;
+ char procdir[64];
+ char line[256];
+ const char *pos;
+ char state;
+ pid_t ppid, pgrp, sess;
+ int len;
+
+ if (!isdigit(dent->d_name[0]))
+ continue;
+
+ snprintf(procdir, sizeof(procdir), "/proc/%s/stat", dent->d_name);
+ procdir[sizeof(procdir)-1] = '\0';
+
+ f = open(procdir, O_RDONLY);
+ if (f == -1)
+ continue;
+
+ len = read(f, line, sizeof(line));
+ close(f);
+
+ if (len <= 0)
+ continue;
+ else
+ line[len] = '\0';
+
+ /* skip ugly program name */
+ pos = strrchr(line, ')') + 2;
+ if (pos == NULL)
+ continue;
+
+ if (sscanf(pos, "%c %d %d %d ", &state, &ppid, &pgrp, &sess) != 4)
+ continue;
+
+ /* count only processes in our session */
+ if (sess != session)
+ continue;
+
+ /* count only running, no sleeping processes */
+ if (state != 'R')
+ continue;
+
+ running++;
+ if (limit > 0 && running >= limit)
+ break;
+ }
+ closedir(dir);
+
+ return running;
+}
+
static int compare_devpath(const char *running, const char *waiting)
{
int i;
struct hotplug_msg *loop_msg;
struct hotplug_msg *tmp_msg;
struct hotplug_msg *msg;
+ int running;
+
+ running = running_processes();
+ dbg("%d processes runnning on system", running);
+ if (running < 0)
+ running = THROTTLE_MAX_RUNNING_CHILDS;
list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, list) {
+ /* check running processes in our session and possibly throttle */
+ if (running >= THROTTLE_MAX_RUNNING_CHILDS) {
+ running = running_processes_in_session(sid, THROTTLE_MAX_RUNNING_CHILDS+10);
+ dbg("%d processes running in session", running);
+ if (running >= THROTTLE_MAX_RUNNING_CHILDS) {
+ dbg("delay seq %llu, cause too many processes already running", loop_msg->seqnum);
+ return;
+ }
+ }
+
msg = running_with_devpath(loop_msg);
if (!msg) {
/* move event to run list */
list_move_tail(&loop_msg->list, &running_list);
udev_run(loop_msg);
+ running++;
dbg("moved seq %llu to running list", loop_msg->seqnum);
} else {
dbg("delay seq %llu (%s), cause seq %llu (%s) is still running",
static void user_sighandler(void)
{
int sig;
+
while(1) {
int rc = read(pipefds[0], &sig, sizeof(sig));
if (rc < 0)
int fd;
struct sigaction act;
fd_set readfds;
+ const char *udevd_expected_seqnum;
logging_init("udevd");
dbg("version %s", UDEV_VERSION);
}
}
+ /* become session leader */
+ sid = setsid();
+ dbg("our session is %d", sid);
+
/* make sure we don't lock any path */
chdir("/");
umask(umask(077) | 022);
+ /*set a reasonable scheduling priority for the daemon */
+ setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
+
/* Set fds to dev/null */
fd = open( "/dev/null", O_RDWR );
- if ( fd < 0 ) {
+ if (fd >= 0) {
+ dup2(fd, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+ if (fd > 2)
+ close(fd);
+ } else
dbg("error opening /dev/null %s", strerror(errno));
- goto exit;
- }
- dup2(fd, 0);
- dup2(fd, 1);
- dup2(fd, 2);
- if (fd > 2)
- close(fd);
-
- /* become session leader */
- setsid();
/* setup signal handler pipe */
retval = pipe(pipefds);
goto exit;
}
retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
- if (retval < 0) {
+ if (retval < 0)
dbg("error fcntl on read pipe: %s", strerror(errno));
- goto exit;
- }
retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
if (retval < 0) {
goto exit;
}
retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
- if (retval < 0) {
+ if (retval < 0)
dbg("error fcntl on write pipe: %s", strerror(errno));
- goto exit;
- }
/* set signal handlers */
+ memset(&act, 0x00, sizeof(struct sigaction));
act.sa_handler = (void (*) (int))sig_handler;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_RESTART;
if (init_udevsend_socket() < 0) {
if (errno == EADDRINUSE)
- dbg("another udevd is running, exit");
+ dbg("another udevd running, exit");
else
dbg("error initialising udevsend socket: %s", strerror(errno));
else
udev_bin = UDEV_BIN;
- /* handle special startup timeout*/
+ /* possible init of expected_seqnum value */
+ udevd_expected_seqnum = getenv("UDEVD_EXPECTED_SEQNUM");
+ if (udevd_expected_seqnum != NULL) {
+ expected_seqnum = strtoull(udevd_expected_seqnum, NULL, 10);
+ dbg("initialize expected_seqnum to %llu", expected_seqnum);
+ }
+
+ /* get current time to provide shorter timeout on startup */
sysinfo(&info);
startup_time = info.uptime;
~ianmdlvl / elogind.git / blobdiff