[ovs-dev] [PATCH] daemon: Make sure that vlog is initialized when a process daemonizes.

[Ben Pfaff]

If a process daemonizes itself, then it should be possible to control that
process's log levels with "ovs-appctl vlog/set" and related commands.  The
vlog_init() function registers those commands.  But vlog_init() doesn't
normally get called until the first log message is issued.  This can take a
while, especially for ovs-controller, where I first noticed the problem.

This commit fixes the problem by calling vlog_init() from
daemonize_start(), which always gets called as a process daemonizes.
---
 lib/daemon.c |    4 ++++
 lib/vlog.c   |    3 ++-
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/lib/daemon.c b/lib/daemon.c
index 6cb553a..c8033fb 100644
--- a/lib/daemon.c
+++ b/lib/daemon.c
@@ -448,6 +448,10 @@ daemonize_start(void)
     }
 
     make_pidfile();
+
+    /* Make sure that the unixctl commands for vlog get registered in a
+     * daemon, even before the first log message. */
+    vlog_init();
 }
 
 /* If daemonization is configured, then this function notifies the parent
diff --git a/lib/vlog.c b/lib/vlog.c
index ddda266..cb0567e 100644
--- a/lib/vlog.c
+++ b/lib/vlog.c
@@ -438,7 +438,8 @@ vlog_unixctl_reopen(struct unixctl_conn *conn,
     }
 }
 
-/* Initializes the logging subsystem. */
+/* Initializes the logging subsystem and registers its unixctl server
+ * commands. */
 void
 vlog_init(void) 
 {
-- 
1.7.1