libceph: distinguish two phases of connect sequence

Currently a ceph connection enters a "CONNECTING" state when it
begins the process of (re-)connecting with its peer.  Once the two
ends have successfully exchanged their banner and addresses, an
additional NEGOTIATING bit is set in the ceph connection's state to
indicate the connection information exhange has begun.  The
CONNECTING bit/state continues to be set during this phase.

Rather than have the CONNECTING state continue while the NEGOTIATING
bit is set, interpret these two phases as distinct states.  In other
words, when NEGOTIATING is set, clear CONNECTING.  That way only
one of them will be active at a time.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 5e67be3fa2966fd39a50c051368611f9e43a43c4..32a3a2a72580044addc4f43c3246c130d96b5a63 100644 (file)
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -1559,7 +1559,6 @@ static int process_connect(struct ceph_connection *con)
                        return -1;
                }
                clear_bit(NEGOTIATING, &con->state);
-               clear_bit(CONNECTING, &con->state);
                set_bit(CONNECTED, &con->state);
                con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
                con->connect_seq++;
@@ -2000,7 +1999,8 @@ more_kvec:
        }
 
 do_next:
-       if (!test_bit(CONNECTING, &con->state)) {
+       if (!test_bit(CONNECTING, &con->state) &&
+                       !test_bit(NEGOTIATING, &con->state)) {
                /* is anything else pending? */
                if (!list_empty(&con->out_queue)) {
                        prepare_write_message(con);
@@ -2057,25 +2057,29 @@ more:
        }
 
        if (test_bit(CONNECTING, &con->state)) {
-               if (!test_bit(NEGOTIATING, &con->state)) {
-                       dout("try_read connecting\n");
-                       ret = read_partial_banner(con);
-                       if (ret <= 0)
-                               goto out;
-                       ret = process_banner(con);
-                       if (ret < 0)
-                               goto out;
-
-                       /* Banner is good, exchange connection info */
-                       ret = prepare_write_connect(con);
-                       if (ret < 0)
-                               goto out;
-                       prepare_read_connect(con);
-                       set_bit(NEGOTIATING, &con->state);
-
-                       /* Send connection info before awaiting response */
+               dout("try_read connecting\n");
+               ret = read_partial_banner(con);
+               if (ret <= 0)
                        goto out;
-               }
+               ret = process_banner(con);
+               if (ret < 0)
+                       goto out;
+
+               clear_bit(CONNECTING, &con->state);
+               set_bit(NEGOTIATING, &con->state);
+
+               /* Banner is good, exchange connection info */
+               ret = prepare_write_connect(con);
+               if (ret < 0)
+                       goto out;
+               prepare_read_connect(con);
+
+               /* Send connection info before awaiting response */
+               goto out;
+       }
+
+       if (test_bit(NEGOTIATING, &con->state)) {
+               dout("try_read negotiating\n");
                ret = read_partial_connect(con);
                if (ret <= 0)
                        goto out;
@@ -2197,12 +2201,12 @@ restart:
        if (test_and_clear_bit(SOCK_CLOSED, &con->flags)) {
                if (test_and_clear_bit(CONNECTED, &con->state))
                        con->error_msg = "socket closed";
-               else if (test_and_clear_bit(CONNECTING, &con->state)) {
-                       clear_bit(NEGOTIATING, &con->state);
+               else if (test_and_clear_bit(NEGOTIATING, &con->state))
+                       con->error_msg = "negotiation failed";
+               else if (test_and_clear_bit(CONNECTING, &con->state))
                        con->error_msg = "connection failed";
-               } else {
+               else
                        con->error_msg = "unrecognized con state";
-               }
                goto fault;
        }