From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Fri, 27 Feb 2015 16:34:44 +0000 (-0500)
Subject: Cleanup: Reduce scope of connections in main relayd thread
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=90e7d72ff2b93752b8c81c49e9251a83b01703c6

Cleanup: Reduce scope of connections in main relayd thread

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index c843aa5ad..a554aedbf 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -2494,7 +2494,6 @@ void *relay_thread_worker(void *data)
 {
 	int ret, err = -1, last_seen_data_fd = -1;
 	uint32_t nb_fd;
-	struct relay_connection *conn;
 	struct lttng_poll_event events;
 	struct lttng_ht *relay_connections_ht;
 	struct lttng_ht_iter iter;
@@ -2502,6 +2501,7 @@ void *relay_thread_worker(void *data)
 	struct relay_local_data *relay_ctx = (struct relay_local_data *) data;
 	struct lttng_ht *sessions_ht = relay_ctx->sessions_ht;
 	struct relay_index *index;
+	struct relay_connection *destroy_conn = NULL;
 
 	DBG("[thread] Relay worker started");
 
@@ -2590,6 +2590,8 @@ restart:
 					ERR("Relay connection pipe error");
 					goto error;
 				} else if (revents & LPOLLIN) {
+					struct relay_connection *conn;
+
 					ret = lttng_read(relay_conn_pipe[0], &conn, sizeof(conn));
 					if (ret < 0) {
 						goto error;
@@ -2605,32 +2607,34 @@ restart:
 					DBG("Connection socket %d added", conn->sock->fd);
 				}
 			} else {
+				struct relay_connection *ctrl_conn;
+
 				rcu_read_lock();
-				conn = connection_find_by_sock(relay_connections_ht, pollfd);
+				ctrl_conn = connection_find_by_sock(relay_connections_ht, pollfd);
 				/* If not found, there is a synchronization issue. */
-				assert(conn);
+				assert(ctrl_conn);
 
 				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
 					cleanup_connection_pollfd(&events, pollfd);
-					destroy_connection(relay_connections_ht, conn);
+					destroy_connection(relay_connections_ht, ctrl_conn);
 					if (last_seen_data_fd == pollfd) {
 						last_seen_data_fd = last_notdel_data_fd;
 					}
 				} else if (revents & LPOLLIN) {
-					if (conn->type == RELAY_CONTROL) {
-						ret = conn->sock->ops->recvmsg(conn->sock, &recv_hdr,
+					if (ctrl_conn->type == RELAY_CONTROL) {
+						ret = ctrl_conn->sock->ops->recvmsg(ctrl_conn->sock, &recv_hdr,
 								sizeof(recv_hdr), 0);
 						if (ret <= 0) {
 							/* Connection closed */
 							cleanup_connection_pollfd(&events, pollfd);
-							destroy_connection(relay_connections_ht, conn);
+							destroy_connection(relay_connections_ht, ctrl_conn);
 							DBG("Control connection closed with %d", pollfd);
 						} else {
-							ret = relay_process_control(&recv_hdr, conn);
+							ret = relay_process_control(&recv_hdr, ctrl_conn);
 							if (ret < 0) {
 								/* Clear the session on error. */
 								cleanup_connection_pollfd(&events, pollfd);
-								destroy_connection(relay_connections_ht, conn);
+								destroy_connection(relay_connections_ht, ctrl_conn);
 								DBG("Connection closed with %d", pollfd);
 							}
 							seen_control = 1;
@@ -2676,6 +2680,7 @@ restart:
 			/* Fetch the poll data. */
 			uint32_t revents = LTTNG_POLL_GETEV(&events, i);
 			int pollfd = LTTNG_POLL_GETFD(&events, i);
+			struct relay_connection *data_conn;
 
 			health_code_update();
 
@@ -2690,24 +2695,24 @@ restart:
 			}
 
 			rcu_read_lock();
-			conn = connection_find_by_sock(relay_connections_ht, pollfd);
-			if (!conn) {
+			data_conn = connection_find_by_sock(relay_connections_ht, pollfd);
+			if (!data_conn) {
 				/* Skip it. Might be removed before. */
 				rcu_read_unlock();
 				continue;
 			}
 
 			if (revents & LPOLLIN) {
-				if (conn->type != RELAY_DATA) {
+				if (data_conn->type != RELAY_DATA) {
 					rcu_read_unlock();
 					continue;
 				}
 
-				ret = relay_process_data(conn);
+				ret = relay_process_data(data_conn);
 				/* Connection closed */
 				if (ret < 0) {
 					cleanup_connection_pollfd(&events, pollfd);
-					destroy_connection(relay_connections_ht, conn);
+					destroy_connection(relay_connections_ht, data_conn);
 					DBG("Data connection closed with %d", pollfd);
 					/*
 					 * Every goto restart call sets the last seen fd where
@@ -2735,10 +2740,11 @@ error:
 
 	/* Cleanup reamaining connection object. */
 	rcu_read_lock();
-	cds_lfht_for_each_entry(relay_connections_ht->ht, &iter.iter, conn,
+	cds_lfht_for_each_entry(relay_connections_ht->ht, &iter.iter,
+			destroy_conn,
 			sock_n.node) {
 		health_code_update();
-		destroy_connection(relay_connections_ht, conn);
+		destroy_connection(relay_connections_ht, destroy_conn);
 	}
 	rcu_read_unlock();
 error_poll_create: