/*
* udevd.c - hotplug event serializer
*
- * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
* Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
*
*
*/
#include <stddef.h>
-#include <sys/wait.h>
#include <signal.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <sys/select.h>
+#include <sys/wait.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>
#include "list.h"
+#include "udev_libc_wrapper.h"
#include "udev.h"
#include "udev_version.h"
#include "udev_utils.h"
/* global variables*/
static int udevsendsock;
+static pid_t sid;
static int pipefds[2];
static long startup_time;
static void reap_sigchilds(void);
char *udev_bin;
-#ifdef LOG
+#ifdef USE_LOG
void log_message (int level, const char *format, ...)
{
va_list args;
#ifdef DEBUG
struct hotplug_msg *msg;
- list_for_each_entry(msg, &msg_list, list)
+ list_for_each_entry(msg, &msg_list, node)
dbg("sequence %llu in queue", msg->seqnum);
#endif
}
static void run_queue_delete(struct hotplug_msg *msg)
{
- list_del(&msg->list);
+ list_del(&msg->node);
free(msg);
}
if (msg->seqnum == 0) {
dbg("no SEQNUM, move straight to the exec queue");
- list_add(&msg->list, &exec_list);
+ list_add(&msg->node, &exec_list);
run_exec_q = 1;
return;
}
/* sort message by sequence number into list */
- list_for_each_entry_reverse(loop_msg, &msg_list, list) {
+ list_for_each_entry_reverse(loop_msg, &msg_list, node) {
if (loop_msg->seqnum < msg->seqnum)
break;
sysinfo(&info);
msg->queue_time = info.uptime;
- list_add(&msg->list, &loop_msg->list);
+ list_add(&msg->node, &loop_msg->node);
dbg("queued message seq %llu", msg->seqnum);
/* run msg queue manager */
/* 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;
- for (i = 0; i < DEVPATH_SIZE; i++) {
+ for (i = 0; i < PATH_SIZE; i++) {
/* identical device event found */
if (running[i] == '\0' && waiting[i] == '\0')
return 1;
if (msg->devpath == NULL)
return NULL;
- list_for_each_entry(loop_msg, &running_list, list) {
+ list_for_each_entry(loop_msg, &running_list, node) {
if (loop_msg->devpath == NULL)
continue;
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, node) {
+ /* 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;
+ }
+ }
- list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, list) {
msg = running_with_devpath(loop_msg);
if (!msg) {
/* move event to run list */
- list_move_tail(&loop_msg->list, &running_list);
+ list_move_tail(&loop_msg->node, &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 msg_move_exec(struct hotplug_msg *msg)
{
- list_move_tail(&msg->list, &exec_list);
+ list_move_tail(&msg->node, &exec_list);
run_exec_q = 1;
expected_seqnum = msg->seqnum+1;
dbg("moved seq %llu to exec, next expected is %llu",
dbg("msg queue manager, next expected is %llu", expected_seqnum);
recheck:
- list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, list) {
+ list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, node) {
/* move event with expected sequence to the exec list */
if (loop_msg->seqnum == expected_seqnum) {
msg_move_exec(loop_msg);
/* find msg associated with pid and delete it */
struct hotplug_msg *msg;
- list_for_each_entry(msg, &running_list, list) {
+ list_for_each_entry(msg, &running_list, node) {
if (msg->pid == pid) {
dbg("<== exec seq %llu came back", msg->seqnum);
run_queue_delete(msg);
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) {
} else
dbg("error opening /dev/null %s", strerror(errno));
- /* become session leader */
- setsid();
-
/* setup signal handler pipe */
retval = pipe(pipefds);
if (retval < 0) {
dbg("error fcntl on write pipe: %s", strerror(errno));
/* 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;
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