chiark / gitweb /
udevd: depend on netlink and remove all sequence reorder logic
authorKay Sievers <kay.sievers@suse.de>
Mon, 7 Nov 2005 01:22:44 +0000 (02:22 +0100)
committerKay Sievers <kay.sievers@suse.de>
Mon, 7 Nov 2005 01:22:44 +0000 (02:22 +0100)
Netlink will never get out-of-order and we just depend on it from
now on. Udevsend messages will have no effect if they contain a
sequence number (SEQNUM).

Thanks to Bastian Blank <waldi@debian.org>, for the debugging session
which identified a bug where the timeouts are not working if
inotify was not available. All the timeout handling is removed
now and this issue should be solved.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Makefile
udev.h
udevd.c
udevd.h
udevsend.c

index 8d280ac..afa649e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -270,7 +270,6 @@ udev_version.h:
        @echo \#define UDEV_CONFIG_DIR          \"$(configdir)\" >> $@
        @echo \#define UDEV_CONFIG_FILE         \"$(configdir)/udev.conf\" >> $@
        @echo \#define UDEV_RULES_FILE          \"$(configdir)/rules.d\" >> $@
-       @echo \#define UDEV_BIN                 \"$(sbindir)/udev\" >> $@
        @echo \#define UDEVD_BIN                \"$(sbindir)/udevd\" >> $@
 
 # man pages
diff --git a/udev.h b/udev.h
index 66edfd6..ecc0a44 100644 (file)
--- a/udev.h
+++ b/udev.h
@@ -36,7 +36,7 @@
 #define VALUE_SIZE                     128
 
 #define DEFAULT_PARTITIONS_COUNT       15
-#define UDEV_ALARM_TIMEOUT             120
+#define UDEV_ALARM_TIMEOUT             180
 
 struct udev_rules;
 
diff --git a/udevd.c b/udevd.c
index 64a6f4d..dcf5781 100644 (file)
--- a/udevd.c
+++ b/udevd.c
 #include <dirent.h>
 #include <fcntl.h>
 #include <syslog.h>
+#include <time.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 <sys/sysinfo.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
-#include <linux/types.h>
 #include <linux/netlink.h>
 
 #include "list.h"
@@ -61,19 +59,14 @@ static pid_t sid;
 
 static int signal_pipe[2] = {-1, -1};
 static volatile int sigchilds_waiting;
-static volatile int run_msg_q;
 static volatile int udev_exit;
 static volatile int reload_config;
-static int init_phase = 1;
 static int run_exec_q;
 static int stop_exec_q;
-static int event_timeout;
 static int max_childs;
 static int max_childs_running;
-static unsigned long long expected_seqnum;
 static char udev_log[32];
 
-static LIST_HEAD(msg_list);
 static LIST_HEAD(exec_list);
 static LIST_HEAD(running_list);
 
@@ -92,14 +85,11 @@ void log_message(int priority, const char *format, ...)
 }
 #endif
 
-static void msg_dump_queue(void)
+static void msg_queue_insert(struct uevent_msg *msg)
 {
-#ifdef DEBUG
-       struct uevent_msg *msg;
-
-       list_for_each_entry(msg, &msg_list, node)
-               dbg("sequence %llu in queue", msg->seqnum);
-#endif
+       list_add(&msg->node, &exec_list);
+       msg->queue_time = time(NULL);
+       run_exec_q = 1;
 }
 
 static void msg_queue_delete(struct uevent_msg *msg)
@@ -108,53 +98,6 @@ static void msg_queue_delete(struct uevent_msg *msg)
        free(msg);
 }
 
-/* orders the message in the queue by sequence number */
-static void msg_queue_insert(struct uevent_msg *msg)
-{
-       struct uevent_msg *loop_msg;
-       struct sysinfo info;
-
-       if (msg->seqnum == 0) {
-               dbg("no SEQNUM, move straight to the exec queue");
-               list_add_tail(&msg->node, &exec_list);
-               run_exec_q = 1;
-               return;
-       }
-
-       /* store timestamp of queuing */
-       sysinfo(&info);
-       msg->queue_time = info.uptime;
-
-       /* with the first event we provide a phase of shorter timeout */
-       if (init_phase) {
-               static long init_time;
-
-               if (init_time == 0)
-                       init_time = info.uptime;
-               if (info.uptime - init_time >= UDEVD_INIT_TIME)
-                       init_phase = 0;
-       }
-
-       /* sort message by sequence number into list */
-       list_for_each_entry_reverse(loop_msg, &msg_list, node) {
-               if (loop_msg->seqnum < msg->seqnum)
-                       break;
-
-               if (loop_msg->seqnum == msg->seqnum) {
-                       dbg("ignoring duplicate message seq %llu", msg->seqnum);
-                       free(msg);
-                       return;
-               }
-       }
-       list_add(&msg->node, &loop_msg->node);
-       info("seq %llu queued, '%s' '%s'", msg->seqnum, msg->action, msg->devpath);
-
-       /* run msg queue manager */
-       run_msg_q = 1;
-
-       return;
-}
-
 static void asmlinkage udev_event_sig_handler(int signum)
 {
        if (signum == SIGALRM)
@@ -205,7 +148,6 @@ static int udev_event_process(struct uevent_msg *msg)
 static void udev_event_run(struct uevent_msg *msg)
 {
        pid_t pid;
-       struct sysinfo info;
 
        pid = fork();
        switch (pid) {
@@ -232,9 +174,8 @@ static void udev_event_run(struct uevent_msg *msg)
                break;
        default:
                /* get SIGCHLD in main loop */
-               sysinfo(&info);
                info("seq %llu forked, pid [%d], '%s' '%s', %ld seconds old",
-                    msg->seqnum, pid,  msg->action, msg->subsystem, info.uptime - msg->queue_time);
+                    msg->seqnum, pid,  msg->action, msg->subsystem, time(NULL) - msg->queue_time);
                msg->pid = pid;
        }
 }
@@ -436,61 +377,6 @@ static void exec_queue_manager(void)
        }
 }
 
-static void msg_move_exec(struct uevent_msg *msg)
-{
-       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",
-               msg->seqnum, expected_seqnum);
-}
-
-/* msg queue management routine handles the timeouts and dispatches the events */
-static void msg_queue_manager(void)
-{
-       struct uevent_msg *loop_msg;
-       struct uevent_msg *tmp_msg;
-       struct sysinfo info;
-       long msg_age = 0;
-       int timeout = event_timeout;
-
-       dbg("msg queue manager, next expected is %llu", expected_seqnum);
-recheck:
-       sysinfo(&info);
-       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);
-                       continue;
-               }
-
-               /* limit timeout during initialization phase */
-               if (init_phase) {
-                       if (timeout > UDEVD_INIT_EVENT_TIMEOUT)
-                               timeout = UDEVD_INIT_EVENT_TIMEOUT;
-                       dbg("initialization phase, timeout %i seconds", timeout);
-               }
-
-               /* move event with expired timeout to the exec list */
-               msg_age = info.uptime - loop_msg->queue_time;
-               dbg("seq %llu is %li seconds old", loop_msg->seqnum, msg_age);
-               if (msg_age >= timeout) {
-                       msg_move_exec(loop_msg);
-                       goto recheck;
-               } else
-                       break;
-       }
-
-       msg_dump_queue();
-
-       /* set timeout for remaining queued events */
-       if (!list_empty(&msg_list)) {
-               struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}};
-               info("next event expires in %li seconds", timeout - msg_age);
-               setitimer(ITIMER_REAL, &itv, NULL);
-       }
-}
-
 static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
 {
        int bufpos;
@@ -691,10 +577,6 @@ static void asmlinkage sig_handler(int signum)
                case SIGTERM:
                        udev_exit = 1;
                        break;
-               case SIGALRM:
-                       /* set flag, then write to pipe if needed */
-                       run_msg_q = 1;
-                       break;
                case SIGCHLD:
                        /* set flag, then write to pipe if needed */
                        sigchilds_waiting = 1;
@@ -712,13 +594,11 @@ static void udev_done(int pid)
 {
        /* find msg associated with pid and delete it */
        struct uevent_msg *msg;
-       struct sysinfo info;
 
        list_for_each_entry(msg, &running_list, node) {
                if (msg->pid == pid) {
-                       sysinfo(&info);
                        if (msg->queue_time)
-                               info("seq %llu, pid [%d] exit, %ld seconds old", msg->seqnum, msg->pid, info.uptime - msg->queue_time);
+                               info("seq %llu, pid [%d] exit, %ld seconds old", msg->seqnum, msg->pid, time(NULL) - msg->queue_time);
                        else
                                info("seq 0, pid [%d] exit", msg->pid);
                        msg_queue_delete(msg);
@@ -818,10 +698,10 @@ int main(int argc, char *argv[], char *envp[])
        struct sigaction act;
        fd_set readfds;
        const char *value;
-       int uevent_netlink_active = 0;
        int daemonize = 0;
        int i;
        int rc = 0;
+       int maxfd;
 
        /* redirect std fd's, if the kernel forks us, we don't have them at all */
        fd = open("/dev/null", O_RDWR);
@@ -943,7 +823,6 @@ int main(int argc, char *argv[], char *envp[])
        act.sa_flags = SA_RESTART;
        sigaction(SIGINT, &act, NULL);
        sigaction(SIGTERM, &act, NULL);
-       sigaction(SIGALRM, &act, NULL);
        sigaction(SIGCHLD, &act, NULL);
        sigaction(SIGHUP, &act, NULL);
 
@@ -952,21 +831,6 @@ int main(int argc, char *argv[], char *envp[])
        if (inotify_fd > 0)
                inotify_add_watch(inotify_fd, udev_rules_filename, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
 
-       /* init of expected_seqnum value */
-       value = getenv("UDEVD_EXPECTED_SEQNUM");
-       if (value) {
-               expected_seqnum = strtoull(value, NULL, 10);
-               info("initialize expected_seqnum to %llu", expected_seqnum);
-       }
-
-       /* timeout to wait for missing events */
-       value = getenv("UDEVD_EVENT_TIMEOUT");
-       if (value)
-               event_timeout = strtoul(value, NULL, 10);
-       else
-               event_timeout = UDEVD_EVENT_TIMEOUT;
-       info("initialize event_timeout to %u", event_timeout);
-
        /* maximum limit of forked childs */
        value = getenv("UDEVD_MAX_CHILDS");
        if (value)
@@ -990,6 +854,11 @@ int main(int argc, char *argv[], char *envp[])
        sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
        putenv(udev_log);
 
+       maxfd = udevd_sock;
+       maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
+       maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
+       maxfd = UDEV_MAX(maxfd, inotify_fd);
+
        while (!udev_exit) {
                struct uevent_msg *msg;
                int fdcount;
@@ -1001,7 +870,7 @@ int main(int argc, char *argv[], char *envp[])
                if (inotify_fd > 0)
                        FD_SET(inotify_fd, &readfds);
 
-               fdcount = select(UDEV_MAX(uevent_netlink_sock, inotify_fd)+1, &readfds, NULL, NULL, NULL);
+               fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
                if (fdcount < 0) {
                        if (errno != EINTR)
                                dbg("error in select: %s", strerror(errno));
@@ -1012,9 +881,8 @@ int main(int argc, char *argv[], char *envp[])
                if (FD_ISSET(udevd_sock, &readfds)) {
                        msg = get_udevd_msg();
                        if (msg) {
-                               /* discard kernel messages if netlink is active */
-                               if (uevent_netlink_active && msg->type == UDEVD_UEVENT_UDEVSEND && msg->seqnum != 0) {
-                                       info("skip uevent_helper message with SEQNUM, netlink is active");
+                               if (msg->type == UDEVD_UEVENT_UDEVSEND && msg->seqnum != 0) {
+                                       info("skip non-kernel message with SEQNUM");
                                        free(msg);
                                } else
                                        msg_queue_insert(msg);
@@ -1024,14 +892,8 @@ int main(int argc, char *argv[], char *envp[])
                /* get kernel netlink message */
                if (FD_ISSET(uevent_netlink_sock, &readfds)) {
                        msg = get_netlink_msg();
-                       if (msg) {
+                       if (msg)
                                msg_queue_insert(msg);
-                               /* disable udevsend with first netlink message */
-                               if (!uevent_netlink_active) {
-                                       info("uevent_nl message received, disable udevsend messages");
-                                       uevent_netlink_active = 1;
-                               }
-                       }
                }
 
                /* received a signal, clear our notification pipe */
@@ -1068,24 +930,13 @@ int main(int argc, char *argv[], char *envp[])
                        udev_rules_init(&rules, 1);
                }
 
-               /* forked child have returned */
+               /* forked child has returned */
                if (sigchilds_waiting) {
                        sigchilds_waiting = 0;
                        reap_sigchilds();
                }
 
-               if (run_msg_q) {
-                       run_msg_q = 0;
-                       msg_queue_manager();
-               }
-
                if (run_exec_q) {
-                        /* clean up running_list before calling exec_queue_manager() */
-                       if (sigchilds_waiting) {
-                               sigchilds_waiting = 0;
-                               reap_sigchilds();
-                       }
-
                        run_exec_q = 0;
                        if (!stop_exec_q)
                                exec_queue_manager();
diff --git a/udevd.h b/udevd.h
index db510ab..884c4b0 100644 (file)
--- a/udevd.h
+++ b/udevd.h
 #define UDEVD_PRIORITY                 -4
 #define UDEV_PRIORITY                  -2
 
-/* duration of initialization phase with shorter timeout */
-#define UDEVD_INIT_TIME                        5
-#define UDEVD_INIT_EVENT_TIMEOUT       2
-
-/* timeout to wait for missing events */
-#define UDEVD_EVENT_TIMEOUT            5
-
 /* maximum limit of runnig childs */
 #define UDEVD_MAX_CHILDS               64
 /* start to throttle forking if maximum number of running childs in our session is reached */
@@ -68,7 +61,7 @@ struct uevent_msg {
        enum udevd_msg_type type;
        struct list_head node;
        pid_t pid;
-       long queue_time;
+       time_t queue_time;
        char *action;
        char *devpath;
        char *subsystem;
index 0ba1b58..29d5bc1 100644 (file)
@@ -89,27 +89,6 @@ static int start_daemon(void)
        return 0;
 }
 
-static void run_udev(const char *subsystem)
-{
-       char *const argv[] = { "udev", (char *)subsystem, NULL };
-       pid_t pid;
-
-       pid = fork();
-       switch (pid) {
-       case 0:
-               /* child */
-               execv(UDEV_BIN, argv);
-               err("exec of udev child failed");
-               _exit(1);
-               break;
-       case -1:
-               err("fork of udev child failed");
-               break;
-       default:
-               waitpid(pid, NULL, 0);
-       }
-}
-
 int main(int argc, char *argv[], char *envp[])
 {
        static struct udevd_msg usend_msg;
@@ -132,7 +111,7 @@ int main(int argc, char *argv[], char *envp[])
        sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
        if (sock == -1) {
                err("error getting socket");
-               goto fallback;
+               goto exit;
        }
 
        memset(&saddr, 0x00, sizeof(struct sockaddr_un));
@@ -192,7 +171,7 @@ int main(int argc, char *argv[], char *envp[])
 
                if (errno != ECONNREFUSED) {
                        err("error sending message (%s)", strerror(errno));
-                       goto fallback;
+                       goto exit;
                }
 
                if (!started_daemon) {
@@ -200,7 +179,7 @@ int main(int argc, char *argv[], char *envp[])
                        retval = start_daemon();
                        if (retval) {
                                dbg("error starting daemon");
-                               goto fallback;
+                               goto exit;
                        }
                        dbg("udevd daemon started");
                        started_daemon = 1;
@@ -210,10 +189,6 @@ int main(int argc, char *argv[], char *envp[])
                }
        }
 
-fallback:
-       err("unable to connect to event daemon, try to call udev directly");
-       run_udev(subsystem);
-
 exit:
        if (sock != -1)
                close(sock);