Fix: rotation error may leave session in "ONGOING" state

[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 545269525ccb73c909d73cba1fcda1ff306496b1..4d4d0088cf8299ed7859c5b1558d4db0aac644f9 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -4531,6 +4531,11 @@ int cmd_rotate_session(struct ltt_session *session,
        struct tm *timeinfo;
        char datetime[21];
        time_t now;
+       /*
+        * Used to roll-back timestamps in case of failure to launch the
+        * rotation.
+        */
+       time_t original_last_chunk_start_ts, original_current_chunk_start_ts;
 
        assert(session);
 
@@ -4611,29 +4616,17 @@ int cmd_rotate_session(struct ltt_session *session,
         * archive id.
         */
        session->current_archive_id++;
-       /*
-        * A rotation has a local step even if the destination is a relay
-        * daemon; the buffers must be consumed by the consumer daemon.
-        */
-       session->rotation_pending_local = true;
-       session->rotation_pending_relay =
-               session_get_consumer_destination_type(session) == CONSUMER_DST_NET;
-       session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
-       ret = notification_thread_command_session_rotation_ongoing(
-                       notification_thread_handle,
-                       session->name, session->uid, session->gid,
-                       session->current_archive_id - 1);
-       if (ret != LTTNG_OK) {
-               ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
-                               session->name);
-       }
 
-       /* Create the path name for the next chunk. */
        now = time(NULL);
        if (now == (time_t) -1) {
                ret = -LTTNG_ERR_ROTATION_NOT_AVAILABLE;
                goto end;
        }
+
+       /* Sample chunk bounds for roll-back in case of error. */
+       original_last_chunk_start_ts = session->last_chunk_start_ts;
+       original_current_chunk_start_ts = session->current_chunk_start_ts;
+
        session->last_chunk_start_ts = session->current_chunk_start_ts;
        session->current_chunk_start_ts = now;
 
@@ -4650,6 +4643,16 @@ int cmd_rotate_session(struct ltt_session *session,
                ret = -LTTNG_ERR_UNK;
                goto end;
        }
+
+       /*
+        * A rotation has a local step even if the destination is a relay
+        * daemon; the buffers must be consumed by the consumer daemon.
+        */
+       session->rotation_pending_local = true;
+       session->rotation_pending_relay =
+               session_get_consumer_destination_type(session) == CONSUMER_DST_NET;
+       session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
+
        if (session->kernel_session) {
                /*
                 * The active path for the next rotation/destroy.
@@ -4663,7 +4666,7 @@ int cmd_rotate_session(struct ltt_session *session,
                if (ret < 0 || ret == sizeof(session->rotation_chunk.active_tracing_path)) {
                        ERR("Failed to format active kernel tracing path in rotate session command");
                        ret = -LTTNG_ERR_UNK;
-                       goto end;
+                       goto error;
                }
                /*
                 * The sub-directory for the consumer
@@ -4676,7 +4679,7 @@ int cmd_rotate_session(struct ltt_session *session,
                if (ret < 0 || ret == sizeof(session->kernel_session->consumer->chunk_path)) {
                        ERR("Failed to format the kernel consumer's sub-directory in rotate session command");
                        ret = -LTTNG_ERR_UNK;
-                       goto end;
+                       goto error;
                }
                /*
                 * Create the new chunk folder, before the rotation begins so we don't
@@ -4689,12 +4692,12 @@ int cmd_rotate_session(struct ltt_session *session,
                        ERR("Failed to create kernel session tracing path at %s",
                                        session->kernel_session->consumer->chunk_path);
                        ret = -LTTNG_ERR_CREATE_DIR_FAIL;
-                       goto end;
+                       goto error;
                }
                ret = kernel_rotate_session(session);
                if (ret != LTTNG_OK) {
                        ret = -ret;
-                       goto end;
+                       goto error;
                }
        }
        if (session->ust_session) {
@@ -4705,7 +4708,7 @@ int cmd_rotate_session(struct ltt_session *session,
                if (ret < 0) {
                        ERR("Failed to format active UST tracing path in rotate session command");
                        ret = -LTTNG_ERR_UNK;
-                       goto end;
+                       goto error;
                }
                ret = snprintf(session->ust_session->consumer->chunk_path,
                                PATH_MAX, "/%s-%" PRIu64, datetime,
@@ -4713,7 +4716,7 @@ int cmd_rotate_session(struct ltt_session *session,
                if (ret < 0) {
                        ERR("Failed to format the UST consumer's sub-directory in rotate session command");
                        ret = -LTTNG_ERR_UNK;
-                       goto end;
+                       goto error;
                }
                /*
                 * Create the new chunk folder, before the rotation begins so we don't
@@ -4724,18 +4727,18 @@ int cmd_rotate_session(struct ltt_session *session,
                                session->ust_session->gid);
                if (ret) {
                        ret = -LTTNG_ERR_CREATE_DIR_FAIL;
-                       goto end;
+                       goto error;
                }
                ret = ust_app_rotate_session(session);
                if (ret != LTTNG_OK) {
-                       goto end;
+                       goto error;
                }
        }
 
        ret = timer_session_rotation_pending_check_start(session,
                        DEFAULT_ROTATE_PENDING_TIMER);
        if (ret) {
-               goto end;
+               goto error;
        }
 
        if (!session->active) {
@@ -4746,12 +4749,30 @@ int cmd_rotate_session(struct ltt_session *session,
                rotate_return->rotation_id = session->current_archive_id;
        }
 
+       ret = notification_thread_command_session_rotation_ongoing(
+                       notification_thread_handle,
+                       session->name, session->uid, session->gid,
+                       session->current_archive_id - 1);
+       if (ret != LTTNG_OK) {
+               ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
+                               session->name);
+       }
+
        DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
                        session->name, session->current_archive_id - 1);
        ret = LTTNG_OK;
 
 end:
        return ret;
+error:
+       session->last_chunk_start_ts = original_last_chunk_start_ts;
+       session->current_archive_id = original_current_chunk_start_ts;
+       if (session_reset_rotation_state(session,
+                       LTTNG_ROTATION_STATE_NO_ROTATION)) {
+               ERR("Failed to reset rotation state of session \"%s\"",
+                               session->name);
+       }
+       goto end;
 }
 
 /*