Improve comments after review

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

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index b688a4c09e45f25c3d62bc82b86cc73bcb23fe16..195174a4edf259d24e2e0d523f0dd243805e4f01 100644 (file)
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -690,9 +690,6 @@ static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
                                        rcu_read_lock();
                                        cds_lfht_for_each_entry(ksess->consumer->socks->ht,
                                                        &iter.iter, socket, node.node) {
-                                               /* Code flow error */
-                                               assert(socket->fd);
-
                                                pthread_mutex_lock(socket->lock);
                                                ret = kernel_consumer_send_channel_stream(socket,
                                                                channel, ksess,
@@ -727,6 +724,12 @@ static void update_ust_app(int app_sock)
 {
        struct ltt_session *sess, *stmp;
 
+       /* Consumer is in an ERROR state. Stop any application update. */
+       if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
+               /* Stop the update process since the consumer is dead. */
+               return;
+       }
+
        /* For all tracing session(s) */
        cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
                session_lock(sess);
@@ -1018,13 +1021,14 @@ restart:
                        lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
                consumer_data->metadata_fd =
                        lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
-               if (consumer_data->cmd_sock < 0 || consumer_data->metadata_fd < 0) {
+               if (consumer_data->cmd_sock < 0
+                               || consumer_data->metadata_fd < 0) {
                        PERROR("consumer connect cmd socket");
                        /* On error, signal condition and quit. */
                        signal_consumer_condition(consumer_data, -1);
                        goto error;
                }
-               consumer_data->metadata_sock.fd = &consumer_data->metadata_fd;
+               consumer_data->metadata_sock.fd_ptr = &consumer_data->metadata_fd;
                /* Create metadata socket lock. */
                consumer_data->metadata_sock.lock = zmalloc(sizeof(pthread_mutex_t));
                if (consumer_data->metadata_sock.lock == NULL) {
@@ -1135,6 +1139,13 @@ restart_poll:
 
 exit:
 error:
+       /*
+        * We lock here because we are about to close the sockets and some other
+        * thread might be using them so get exclusive access which will abort all
+        * other consumer command by other threads.
+        */
+       pthread_mutex_lock(&consumer_data->lock);
+
        /* Immediately set the consumerd state to stopped */
        if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
                uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
@@ -1160,15 +1171,12 @@ error:
                }
                consumer_data->cmd_sock = -1;
        }
-       if (*consumer_data->metadata_sock.fd >= 0) {
-               ret = close(*consumer_data->metadata_sock.fd);
+       if (*consumer_data->metadata_sock.fd_ptr >= 0) {
+               ret = close(*consumer_data->metadata_sock.fd_ptr);
                if (ret) {
                        PERROR("close");
                }
        }
-       /* Cleanup metadata socket mutex. */
-       pthread_mutex_destroy(consumer_data->metadata_sock.lock);
-       free(consumer_data->metadata_sock.lock);
 
        if (sock >= 0) {
                ret = close(sock);
@@ -1180,6 +1188,11 @@ error:
        unlink(consumer_data->err_unix_sock_path);
        unlink(consumer_data->cmd_unix_sock_path);
        consumer_data->pid = 0;
+       pthread_mutex_unlock(&consumer_data->lock);
+
+       /* Cleanup metadata socket mutex. */
+       pthread_mutex_destroy(consumer_data->metadata_sock.lock);
+       free(consumer_data->metadata_sock.lock);
 
        lttng_poll_clean(&events);
 error_poll: