xenstored: Delay forking until after listening sockets are

opened. Also, in startup xend script, delay further startup until
xenstored initial child process has exited. This serialises xenstored
startup with that of other daemons (e.g., xenconsoled).

Signed-off-by: Bastian Blank <waldi@debian.org>

diff --git a/tools/misc/xend b/tools/misc/xend
index 7cb617630d044f25503a16f5904d764e17d74030..15e9b8a53fed58fa8853e8f97d2e0bdff88c837f 100644 (file)
--- a/tools/misc/xend
+++ b/tools/misc/xend
@@ -95,11 +95,17 @@ def start_xenstored():
         f.close()
     except:
         pass
-    XENSTORED_TRACE = os.getenv("XENSTORED_TRACE")
-    cmd = "xenstored --pid-file /var/run/xenstore.pid"
-    if XENSTORED_TRACE:
-        cmd += " -T /var/log/xen/xenstored-trace.log"
-    s,o = commands.getstatusoutput(cmd)
+    args = ['xenstored', "--pid-file", pidfname]
+    if os.getenv("XENSTORED_TRACE"):
+        args.extend(["-T", "/var/log/xen/xenstored-trace.log"])
+    pid = os.fork()
+    if pid == 0:
+        os.execvp('xenstored', args)
+    p, status = os.waitpid(pid, 0)
+    if os.WIFEXITED(status):
+        status = os.WEXITSTATUS(status)
+        if status:
+            raise RuntimeError("Failed to start xenstored: %d" % status)
 
 def start_consoled():
     if os.fork() == 0:

diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c
index a643f2d9690c84a41605d84827ff174b1a5411dc..37ceab8493410ea4dcfecc05f21c71d57dde915a 100644 (file)
--- a/tools/xenstore/xenstored_core.c
+++ b/tools/xenstore/xenstored_core.c
@@ -1839,13 +1839,6 @@ int main(int argc, char *argv[])
                }
        }
 
-       if (dofork) {
-               openlog("xenstored", 0, LOG_DAEMON);
-               daemonize();
-       }
-       if (pidfile)
-               write_pidfile(pidfile);
-
        /* Talloc leak reports go to stderr, which is closed if we fork. */
        if (!dofork)
                talloc_enable_leak_report_full();
@@ -1899,16 +1892,21 @@ int main(int argc, char *argv[])
        /* Restore existing connections. */
        restore_existing_connections();
 
-       if (outputpid) {
-               printf("%ld\n", (long)getpid());
-               fflush(stdout);
-       }
-
        /* redirect to /dev/null now we're ready to accept connections */
        if (dofork) {
                int devnull = open("/dev/null", O_RDWR);
                if (devnull == -1)
                        barf_perror("Could not open /dev/null\n");
+
+               openlog("xenstored", 0, LOG_DAEMON);
+
+               daemonize();
+
+               if (outputpid) {
+                       printf("%ld\n", (long)getpid());
+                       fflush(stdout);
+               }
+
                dup2(devnull, STDIN_FILENO);
                dup2(devnull, STDOUT_FILENO);
                dup2(devnull, STDERR_FILENO);
@@ -1916,6 +1914,9 @@ int main(int argc, char *argv[])
                xprintf = trace;
        }
 
+       if (pidfile)
+               write_pidfile(pidfile);
+
        signal(SIGHUP, trigger_reopen_log);
 
        if (xce_handle != -1)