From ab166d5aa3bc036fba7efaca6e4e43a7e9510acf Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Thu, 31 May 2012 11:37:29 -0500 Subject: [PATCH] libceph: separate banner and connect writes There are two phases in the process of linking together the two ends of a ceph connection. The first involves exchanging a banner and IP addresses, and if that is successful a second phase exchanges some detail about each side's connection capabilities. When initiating a connection, the client side now queues to send its information for both phases of this process at the same time. This is probably a bit more efficient, but it is slightly messier from a layering perspective in the code. So rearrange things so that the client doesn't send the connection information until it has received and processed the response in the initial banner phase (in process_banner()). Move the code (in the (con->sock == NULL) case in try_write()) that prepares for writing the connection information, delaying doing that until the banner exchange has completed. Move the code that begins the transition to this second "NEGOTIATING" phase out of process_banner() and into its caller, so preparing to write the connection information and preparing to read the response are adjacent to each other. Finally, preparing to write the connection information now requires the output kvec to be reset in all cases, so move that into the prepare_write_connect() and delete it from all callers. Signed-off-by: Alex Elder Reviewed-by: Sage Weil --- net/ceph/messenger.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 83bcf977e9b9..5e67be3fa296 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -841,6 +841,7 @@ static int prepare_write_connect(struct ceph_connection *con) con->out_connect.authorizer_len = auth ? cpu_to_le32(auth->authorizer_buf_len) : 0; + con_out_kvec_reset(con); con_out_kvec_add(con, sizeof (con->out_connect), &con->out_connect); if (auth && auth->authorizer_buf_len) @@ -1430,8 +1431,6 @@ static int process_banner(struct ceph_connection *con) ceph_pr_addr(&con->msgr->inst.addr.in_addr)); } - set_bit(NEGOTIATING, &con->state); - prepare_read_connect(con); return 0; } @@ -1481,7 +1480,6 @@ static int process_connect(struct ceph_connection *con) return -1; } con->auth_retry = 1; - con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; @@ -1502,7 +1500,6 @@ static int process_connect(struct ceph_connection *con) ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr)); reset_connection(con); - con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; @@ -1528,7 +1525,6 @@ static int process_connect(struct ceph_connection *con) le32_to_cpu(con->out_connect.connect_seq), le32_to_cpu(con->in_connect.connect_seq)); con->connect_seq = le32_to_cpu(con->in_connect.connect_seq); - con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; @@ -1545,7 +1541,6 @@ static int process_connect(struct ceph_connection *con) le32_to_cpu(con->in_connect.global_seq)); get_global_seq(con->msgr, le32_to_cpu(con->in_connect.global_seq)); - con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; @@ -1958,9 +1953,6 @@ more: con_out_kvec_reset(con); prepare_write_banner(con); - ret = prepare_write_connect(con); - if (ret < 0) - goto out; prepare_read_banner(con); BUG_ON(con->in_msg); @@ -2073,6 +2065,16 @@ more: 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 */ + goto out; } ret = read_partial_connect(con); if (ret <= 0) -- 2.30.2