Fix: flush the rotation thread's job queue on exit

[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 64f958233cdc6ccb22ee671a5d5feb51fd6cae67..043993a60484130450dbe3dd75818b72ea9f4b66 100644 (file)
--- a/src/bin/lttng-sessiond/rotation-thread.c
+++ b/src/bin/lttng-sessiond/rotation-thread.c
@@ -75,7 +75,6 @@ struct rotation_thread_handle {
        struct rotation_thread_timer_queue *rotation_timer_queue;
        /* Access to the notification thread cmd_queue */
        struct notification_thread_handle *notification_thread_handle;
-       sem_t *notification_thread_ready;
 };
 
 static
@@ -169,8 +168,7 @@ void rotation_thread_handle_destroy(
 
 struct rotation_thread_handle *rotation_thread_handle_create(
                struct rotation_thread_timer_queue *rotation_timer_queue,
-               struct notification_thread_handle *notification_thread_handle,
-               sem_t *notification_thread_ready)
+               struct notification_thread_handle *notification_thread_handle)
 {
        struct rotation_thread_handle *handle;
 
@@ -181,7 +179,6 @@ struct rotation_thread_handle *rotation_thread_handle_create(
 
        handle->rotation_timer_queue = rotation_timer_queue;
        handle->notification_thread_handle = notification_thread_handle;
-       handle->notification_thread_ready = notification_thread_ready;
 
 end:
        return handle;
@@ -320,11 +317,6 @@ int init_thread_state(struct rotation_thread_handle *handle,
                goto end;
        }
 
-       /*
-        * We wait until the notification thread is ready to create the
-        * notification channel and add it to the poll_set.
-        */
-       sem_wait(handle->notification_thread_ready);
        rotate_notification_channel = lttng_notification_channel_create(
                        lttng_session_daemon_notification_endpoint);
        if (!rotate_notification_channel) {
@@ -535,6 +527,19 @@ int check_session_rotation_pending(struct ltt_session *session,
        DBG("[rotation-thread] Checking for pending rotation on session \"%s\", trace archive %" PRIu64,
                        session->name, session->current_archive_id - 1);
 
+       /*
+        * The rotation-pending check timer of a session is launched in
+        * one-shot mode. If the rotation is incomplete, the rotation
+        * thread will re-enable the pending-check timer.
+        *
+        * The timer thread can't stop the timer itself since it is involved
+        * in the check for the timer's quiescence.
+        */
+       ret = timer_session_rotation_pending_check_stop(session);
+       if (ret) {
+               goto end;
+       }
+
        if (session->rotation_pending_local) {
                /* Updates session->rotation_pending_local as needed. */
                ret = check_session_rotation_pending_local(session);
@@ -710,15 +715,6 @@ int handle_job_queue(struct rotation_thread_handle *handle,
                struct rotation_thread_timer_queue *queue)
 {
        int ret = 0;
-       int fd = lttng_pipe_get_readfd(queue->event_pipe);
-       char buf;
-
-       ret = lttng_read(fd, &buf, 1);
-       if (ret != 1) {
-               ERR("[rotation-thread] Failed to read from wakeup pipe (fd = %i)", fd);
-               ret = -1;
-               goto end;
-       }
 
        for (;;) {
                struct ltt_session *session;
@@ -759,6 +755,7 @@ int handle_job_queue(struct rotation_thread_handle *handle,
                session_lock(session);
                ret = run_job(job, session, handle->notification_thread_handle);
                session_unlock(session);
+               /* Release reference held by the job. */
                session_put(session);
                session_unlock_list();
                free(job);
@@ -971,23 +968,43 @@ void *thread_rotation(void *data)
                                goto error;
                        }
 
-                       if (sessiond_check_thread_quit_pipe(fd, revents)) {
-                               DBG("[rotation-thread] Quit pipe activity");
-                               /* TODO flush the queue. */
-                               goto exit;
-                       } else if (fd == lttng_pipe_get_readfd(handle->rotation_timer_queue->event_pipe)) {
+                       if (fd == rotate_notification_channel->socket) {
+                               ret = handle_notification_channel(fd, handle,
+                                               &thread);
+                               if (ret) {
+                                       ERR("[rotation-thread] Error occurred while handling activity on notification channel socket");
+                                       goto error;
+                               }
+                       } else {
+                               /* Job queue or quit pipe activity. */
+                               if (fd == lttng_pipe_get_readfd(
+                                               handle->rotation_timer_queue->event_pipe)) {
+                                       char buf;
+
+                                       ret = lttng_read(fd, &buf, 1);
+                                       if (ret != 1) {
+                                               ERR("[rotation-thread] Failed to read from wakeup pipe (fd = %i)", fd);
+                                               ret = -1;
+                                               goto error;
+                                       }
+                               }
+
+                               /*
+                                * The job queue is serviced if there is
+                                * activity on the quit pipe to ensure it is
+                                * flushed and all references held in the queue
+                                * are released.
+                                */
                                ret = handle_job_queue(handle, &thread,
                                                handle->rotation_timer_queue);
                                if (ret) {
                                        ERR("[rotation-thread] Failed to handle rotation timer pipe event");
                                        goto error;
                                }
-                       } else if (fd == rotate_notification_channel->socket) {
-                               ret = handle_notification_channel(fd, handle,
-                                               &thread);
-                               if (ret) {
-                                       ERR("[rotation-thread] Error occurred while handling activity on notification channel socket");
-                                       goto error;
+
+                               if (sessiond_check_thread_quit_pipe(fd, revents)) {
+                                       DBG("[rotation-thread] Quit pipe activity");
+                                       goto exit;
                                }
                        }
                }