libceph: don't change socket state on sock event

Currently the socket state change event handler records an error
message on a connection to distinguish a close while connecting from
a close while a connection was already established.

Changing connection information during handling of a socket event is
not very clean, so instead move this assignment inside con_work(),
where it can be done during normal connection-level processing (and
under protection of the connection mutex as well).

Move the handling of a socket closed event up to the top of the
processing loop in con_work(); there's no point in handling backoff
etc. if we have a newly-closed socket to take care of.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

net/ceph/messenger.c

@@ -261,13 +261,8 @@ static void ceph_sock_state_change(struct sock *sk)
 	case TCP_CLOSE_WAIT:
 		dout("%s TCP_CLOSE_WAIT\n", __func__);
 		con_sock_state_closing(con);
-		if (test_and_set_bit(SOCK_CLOSED, &con->flags) == 0) {
-			if (test_bit(CONNECTING, &con->state))
-				con->error_msg = "connection failed";
-			else
-				con->error_msg = "socket closed";
+		if (!test_and_set_bit(SOCK_CLOSED, &con->flags))
 			queue_con(con);
-		}
 		break;
 	case TCP_ESTABLISHED:
 		dout("%s TCP_ESTABLISHED\n", __func__);
@@ -2187,6 +2182,14 @@ static void con_work(struct work_struct *work)
 
 	mutex_lock(&con->mutex);
 restart:
+	if (test_and_clear_bit(SOCK_CLOSED, &con->flags)) {
+		if (test_bit(CONNECTING, &con->state))
+			con->error_msg = "connection failed";
+		else
+			con->error_msg = "socket closed";
+		goto fault;
+	}
+
 	if (test_and_clear_bit(BACKOFF, &con->flags)) {
 		dout("con_work %p backing off\n", con);
 		if (queue_delayed_work(ceph_msgr_wq, &con->work,
@@ -2216,9 +2219,6 @@ static void con_work(struct work_struct *work)
 		con_close_socket(con);
 	}
 
-	if (test_and_clear_bit(SOCK_CLOSED, &con->flags))
-		goto fault;
-
 	ret = try_read(con);
 	if (ret == -EAGAIN)
 		goto restart;