Fix: session_list lock must be held to launch a rotation

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

diff --git a/src/bin/lttng-sessiond/rotation-thread.c b/src/bin/lttng-sessiond/rotation-thread.c
index 3747ebae7fe337713c1758ad08fe2b8c1c775f10..3256a1e9b6581899380cb47f16cb35b10a90b32c 100644 (file)
--- a/src/bin/lttng-sessiond/rotation-thread.c
+++ b/src/bin/lttng-sessiond/rotation-thread.c
@@ -72,7 +72,6 @@ struct rotation_thread_timer_queue {
 };
 
 struct rotation_thread_handle {
-       int quit_pipe;
        struct rotation_thread_timer_queue *rotation_timer_queue;
        /* Access to the notification thread cmd_queue */
        struct notification_thread_handle *notification_thread_handle;
@@ -169,7 +168,6 @@ void rotation_thread_handle_destroy(
 }
 
 struct rotation_thread_handle *rotation_thread_handle_create(
-               int quit_pipe,
                struct rotation_thread_timer_queue *rotation_timer_queue,
                struct notification_thread_handle *notification_thread_handle,
                sem_t *notification_thread_ready)
@@ -181,7 +179,6 @@ struct rotation_thread_handle *rotation_thread_handle_create(
                goto end;
        }
 
-       handle->quit_pipe = quit_pipe;
        handle->rotation_timer_queue = rotation_timer_queue;
        handle->notification_thread_handle = notification_thread_handle;
        handle->notification_thread_ready = notification_thread_ready;
@@ -276,15 +273,8 @@ int init_poll_set(struct lttng_poll_event *poll_set,
         *      - quit pipe,
         *      - rotation thread timer queue pipe,
         */
-       ret = lttng_poll_create(poll_set, 2, LTTNG_CLOEXEC);
-       if (ret < 0) {
-               goto end;
-       }
-
-       ret = lttng_poll_add(poll_set, handle->quit_pipe,
-                       LPOLLIN | LPOLLERR);
-       if (ret < 0) {
-               ERR("[rotation-thread] Failed to add quit_pipe fd to pollset");
+       ret = sessiond_set_thread_pollset(poll_set, 2);
+       if (ret) {
                goto error;
        }
        ret = lttng_poll_add(poll_set,
@@ -295,7 +285,6 @@ int init_poll_set(struct lttng_poll_event *poll_set,
                goto error;
        }
 
-end:
        return ret;
 error:
        lttng_poll_clean(poll_set);
@@ -598,6 +587,44 @@ int check_session_rotation_pending(struct ltt_session *session,
                                session->name);
        }
 
+       if (!session->active) {
+               /*
+                * A stop command was issued during the rotation, it is
+                * up to the rotation completion check to perform the
+                * renaming of the last chunk that was produced.
+                */
+               ret = notification_thread_command_session_rotation_ongoing(
+                               notification_thread_handle,
+                               session->name,
+                               session->uid,
+                               session->gid,
+                               session->current_archive_id);
+               if (ret != LTTNG_OK) {
+                       ERR("[rotation-thread] Failed to notify notification thread of completed rotation for session %s",
+                                       session->name);
+               }
+
+               ret = rename_active_chunk(session);
+               if (ret < 0) {
+                       ERR("[rotation-thread] Failed to rename active rotation chunk");
+                       goto end;
+               }
+
+               /* Ownership of location is transferred. */
+               location = session_get_trace_archive_location(session);
+               ret = notification_thread_command_session_rotation_completed(
+                               notification_thread_handle,
+                               session->name,
+                               session->uid,
+                               session->gid,
+                               session->current_archive_id,
+                               location);
+               if (ret != LTTNG_OK) {
+                       ERR("[rotation-thread] Failed to notify notification thread of completed rotation for session %s",
+                                       session->name);
+               }
+       }
+
        ret = 0;
 end:
        if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
@@ -615,7 +642,7 @@ end:
        return ret;
 }
 
-/* Call with the session lock held. */
+/* Call with the session and session_list locks held. */
 static
 int launch_session_rotation(struct ltt_session *session)
 {
@@ -709,10 +736,9 @@ int handle_job_queue(struct rotation_thread_handle *handle,
                }
 
                session_lock(session);
-               session_unlock_list();
-
                ret = run_job(job, session, handle->notification_thread_handle);
                session_unlock(session);
+               session_unlock_list();
                free(job);
                if (ret) {
                        goto end;
@@ -777,7 +803,7 @@ int handle_condition(const struct lttng_condition *condition,
        ret = unsubscribe_session_consumed_size_rotation(session,
                        notification_thread_handle);
        if (ret) {
-               goto end;
+               goto end_unlock;
        }
 
        ret = cmd_rotate_session(session, NULL);
@@ -876,12 +902,15 @@ void *thread_rotation(void *data)
                goto end;
        }
 
+       rcu_register_thread();
+       rcu_thread_online();
+
        health_register(health_sessiond, HEALTH_SESSIOND_TYPE_ROTATION);
        health_code_update();
 
        ret = init_thread_state(handle, &thread);
        if (ret) {
-               goto end;
+               goto error;
        }
 
        /* Ready to handle client connections. */
@@ -919,7 +948,7 @@ void *thread_rotation(void *data)
                                goto error;
                        }
 
-                       if (fd == handle->quit_pipe) {
+                       if (sessiond_check_thread_quit_pipe(fd, revents)) {
                                DBG("[rotation-thread] Quit pipe activity");
                                /* TODO flush the queue. */
                                goto exit;
@@ -945,6 +974,8 @@ error:
        DBG("[rotation-thread] Exit");
        fini_thread_state(&thread);
        health_unregister(health_sessiond);
+       rcu_thread_offline();
+       rcu_unregister_thread();
 end:
        return NULL;
 }