From bc18f4b1c850ab355e38373fbb60fd28568d84b5 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 20 Jun 2012 21:53:53 -0500 Subject: [PATCH] libceph: add some fine ASCII art Sage liked the state diagram I put in my commit description so I'm putting it in with the code. Signed-off-by: Alex Elder Reviewed-by: Sage Weil --- net/ceph/messenger.c | 42 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 4578e99bbef1..dcc50e4cd5cd 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -29,7 +29,47 @@ * the sender. */ -/* State values for ceph_connection->sock_state; NEW is assumed to be 0 */ +/* + * We track the state of the socket on a given connection using + * values defined below. The transition to a new socket state is + * handled by a function which verifies we aren't coming from an + * unexpected state. + * + * -------- + * | NEW* | transient initial state + * -------- + * | con_sock_state_init() + * v + * ---------- + * | CLOSED | initialized, but no socket (and no + * ---------- TCP connection) + * ^ \ + * | \ con_sock_state_connecting() + * | ---------------------- + * | \ + * + con_sock_state_closed() \ + * |\ \ + * | \ \ + * | ----------- \ + * | | CLOSING | socket event; \ + * | ----------- await close \ + * | ^ | + * | | | + * | + con_sock_state_closing() | + * | / \ | + * | / --------------- | + * | / \ v + * | / -------------- + * | / -----------------| CONNECTING | socket created, TCP + * | | / -------------- connect initiated + * | | | con_sock_state_connected() + * | | v + * ------------- + * | CONNECTED | TCP connection established + * ------------- + * + * State values for ceph_connection->sock_state; NEW is assumed to be 0. + */ #define CON_SOCK_STATE_NEW 0 /* -> CLOSED */ #define CON_SOCK_STATE_CLOSED 1 /* -> CONNECTING */