Use free running metadata channel key between sessiond and kernel consumer

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

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index 58b81477b6bd8345bfafc9c603abd9e2686b49dc..803a88090c95d28a733f7e04614238c830980055 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -167,14 +167,14 @@ static int get_kernel_runtime_stats(struct ltt_session *session,
                goto end;
        }
 
-       ret = consumer_get_discarded_events(session->id, kchan->fd,
+       ret = consumer_get_discarded_events(session->id, kchan->key,
                        session->kernel_session->consumer,
                        discarded_events);
        if (ret < 0) {
                goto end;
        }
 
-       ret = consumer_get_lost_packets(session->id, kchan->fd,
+       ret = consumer_get_lost_packets(session->id, kchan->key,
                        session->kernel_session->consumer,
                        lost_packets);
        if (ret < 0) {
@@ -784,17 +784,17 @@ static int add_uri_to_consumer(struct consumer_output *consumer,
                break;
        case LTTNG_DST_PATH:
                DBG2("Setting trace directory path from URI to %s", uri->dst.path);
-               memset(consumer->dst.trace_path, 0,
-                               sizeof(consumer->dst.trace_path));
+               memset(consumer->dst.session_root_path, 0,
+                               sizeof(consumer->dst.session_root_path));
                /* Explicit length checks for strcpy and strcat. */
                if (strlen(uri->dst.path) + strlen(default_trace_dir)
-                               >= sizeof(consumer->dst.trace_path)) {
+                               >= sizeof(consumer->dst.session_root_path)) {
                        ret = LTTNG_ERR_FATAL;
                        goto error;
                }
-               strcpy(consumer->dst.trace_path, uri->dst.path);
+               strcpy(consumer->dst.session_root_path, uri->dst.path);
                /* Append default trace dir */
-               strcat(consumer->dst.trace_path, default_trace_dir);
+               strcat(consumer->dst.session_root_path, default_trace_dir);
                /* Flag consumer as local. */
                consumer->type = CONSUMER_DST_LOCAL;
                break;
@@ -877,8 +877,11 @@ static int create_connect_relayd(struct lttng_uri *uri,
 
                /* Check relayd version */
                ret = relayd_version_check(rsock);
-               if (ret < 0) {
-                       ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
+               if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
+                       goto close_sock;
+               } else if (ret < 0) {
+                       ERR("Unable to reach lttng-relayd");
+                       ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
                        goto close_sock;
                }
                consumer->relay_major_version = rsock->major;
@@ -907,6 +910,8 @@ error:
 
 /*
  * Connect to the relayd using URI and send the socket to the right consumer.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
                unsigned int session_id, struct lttng_uri *relayd_uri,
@@ -920,7 +925,7 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
        /* Connect to relayd and make version check if uri is the control. */
        ret = create_connect_relayd(relayd_uri, &rsock, consumer);
        if (ret != LTTNG_OK) {
-               goto error;
+               goto relayd_comm_error;
        }
        assert(rsock);
 
@@ -960,10 +965,6 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
         */
 
 close_sock:
-       (void) relayd_close(rsock);
-       free(rsock);
-
-error:
        if (ret != LTTNG_OK) {
                /*
                 * The consumer output for this session should not be used anymore
@@ -972,6 +973,10 @@ error:
                 */
                consumer->enabled = 0;
        }
+       (void) relayd_close(rsock);
+       free(rsock);
+
+relayd_comm_error:
        return ret;
 }
 
@@ -979,6 +984,8 @@ error:
  * Send both relayd sockets to a specific consumer and domain.  This is a
  * helper function to facilitate sending the information to the consumer for a
  * session.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
                unsigned int session_id, struct consumer_output *consumer,
@@ -1650,6 +1657,16 @@ int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
        int ret, chan_kern_created = 0, chan_ust_created = 0;
        char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
 
+       /*
+        * Don't try to add a context if the session has been started at
+        * some point in time before. The tracer does not allow it and would
+        * result in a corrupted trace.
+        */
+       if (session->has_been_started) {
+               ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+               goto end;
+       }
+
        if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
                app_ctx_provider_name = ctx->u.app_ctx.provider_name;
                app_ctx_name = ctx->u.app_ctx.ctx_name;
@@ -3082,7 +3099,7 @@ void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
                                        sizeof(sessions[i].path), session);
                } else {
                        ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
-                                       session->consumer->dst.trace_path);
+                                       session->consumer->dst.session_root_path);
                }
                if (ret < 0) {
                        PERROR("snprintf session path");
@@ -3319,7 +3336,7 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
                }
                if (output->consumer->type == CONSUMER_DST_LOCAL) {
                        if (lttng_strncpy(list[idx].ctrl_url,
-                                       output->consumer->dst.trace_path,
+                                       output->consumer->dst.session_root_path,
                                        sizeof(list[idx].ctrl_url))) {
                                ret = -LTTNG_ERR_INVALID;
                                goto error;
@@ -3550,7 +3567,6 @@ int cmd_regenerate_statedump(struct ltt_session *session)
                ret = LTTNG_ERR_SESSION_NOT_STARTED;
                goto end;
        }
-       ret = 0;
 
        if (session->kernel_session) {
                ret = kernctl_session_regenerate_statedump(
@@ -3707,10 +3723,12 @@ static int set_relayd_for_snapshot(struct consumer_output *consumer,
        rcu_read_lock();
        cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
                        socket, node.node) {
+               pthread_mutex_lock(socket->lock);
                ret = send_consumer_relayd_sockets(0, session->id,
                                snap_output->consumer, socket,
                                session->name, session->hostname,
                                session->live_timer);
+               pthread_mutex_unlock(socket->lock);
                if (ret != LTTNG_OK) {
                        rcu_read_unlock();
                        goto error;