Fix: compat poll: add missing empty revents checks

[lttng-tools.git] / src / bin / lttng-relayd / main.c

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index 1ec1eeaa4b14be22fa0a8cde2d708279a50bcf4b..94bb4cb8e6a1ea24924e96e449dbb0c610aee85e 100644 (file)
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -868,6 +868,11 @@ restart:
                        revents = LTTNG_POLL_GETEV(&events, i);
                        pollfd = LTTNG_POLL_GETFD(&events, i);
 
+                       if (!revents) {
+                               /* No activity for this FD (poll implementation). */
+                               continue;
+                       }
+
                        /* Thread quit pipe has been closed. Killing thread. */
                        ret = check_thread_quit_pipe(pollfd, revents);
                        if (ret) {
@@ -2536,6 +2541,11 @@ restart:
 
                        health_code_update();
 
+                       if (!revents) {
+                               /* No activity for this FD (poll implementation). */
+                               continue;
+                       }
+
                        /* Thread quit pipe has been closed. Killing thread. */
                        ret = check_thread_quit_pipe(pollfd, revents);
                        if (ret) {
@@ -2638,46 +2648,49 @@ restart:
 
                        health_code_update();
 
+                       if (!revents) {
+                               /* No activity for this FD (poll implementation). */
+                               continue;
+                       }
+
                        /* Skip the command pipe. It's handled in the first loop. */
                        if (pollfd == relay_conn_pipe[0]) {
                                continue;
                        }
 
-                       if (revents) {
-                               rcu_read_lock();
-                               conn = connection_find_by_sock(relay_connections_ht, pollfd);
-                               if (!conn) {
-                                       /* Skip it. Might be removed before. */
+                       rcu_read_lock();
+                       conn = connection_find_by_sock(relay_connections_ht, pollfd);
+                       if (!conn) {
+                               /* Skip it. Might be removed before. */
+                               rcu_read_unlock();
+                               continue;
+                       }
+
+                       if (revents & LPOLLIN) {
+                               if (conn->type != RELAY_DATA) {
                                        rcu_read_unlock();
                                        continue;
                                }
 
-                               if (revents & LPOLLIN) {
-                                       if (conn->type != RELAY_DATA) {
-                                               rcu_read_unlock();
-                                               continue;
-                                       }
-
-                                       ret = relay_process_data(conn);
-                                       /* Connection closed */
-                                       if (ret < 0) {
-                                               cleanup_connection_pollfd(&events, pollfd);
-                                               destroy_connection(relay_connections_ht, conn);
-                                               DBG("Data connection closed with %d", pollfd);
-                                               /*
-                                                * Every goto restart call sets the last seen fd where
-                                                * here we don't really care since we gracefully
-                                                * continue the loop after the connection is deleted.
-                                                */
-                                       } else {
-                                               /* Keep last seen port. */
-                                               last_seen_data_fd = pollfd;
-                                               rcu_read_unlock();
-                                               goto restart;
-                                       }
+                               ret = relay_process_data(conn);
+                               /* Connection closed */
+                               if (ret < 0) {
+                                       cleanup_connection_pollfd(&events, pollfd);
+                                       destroy_connection(relay_connections_ht, conn);
+                                       DBG("Data connection closed with %d", pollfd);
+                                       /*
+                                        * Every goto restart call sets the last seen fd where
+                                        * here we don't really care since we gracefully
+                                        * continue the loop after the connection is deleted.
+                                        */
+                               } else {
+                                       /* Keep last seen port. */
+                                       last_seen_data_fd = pollfd;
+                                       rcu_read_unlock();
+                                       goto restart;
                                }
-                               rcu_read_unlock();
                        }
+                       rcu_read_unlock();
                }
                last_seen_data_fd = -1;
        }