Fix: missing RCU read side critical sections

[lttng-tools.git] / src / bin / lttng-sessiond / action-executor.cpp

diff --git a/src/bin/lttng-sessiond/action-executor.cpp b/src/bin/lttng-sessiond/action-executor.cpp
index 53d831354d21f19942def858f334241b14ac37ab..34d3b7130f0a713b089bff4461cab34c9ce36445 100644 (file)
--- a/src/bin/lttng-sessiond/action-executor.cpp
+++ b/src/bin/lttng-sessiond/action-executor.cpp
@@ -301,7 +301,7 @@ static int action_executor_start_session_handler(
         * existed. If not skip the action altogether.
         */
        if (!item->context.session_id.is_set) {
-               DBG("Session `%s` was not present at the moment the work item was enqueued for %s` action of trigger `%s`",
+               DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`",
                                session_name, get_action_name(action),
                                get_trigger_name(work_item->trigger));
                lttng_action_increase_execution_failure_count(action);
@@ -309,6 +309,7 @@ static int action_executor_start_session_handler(
        }
 
        session_lock_list();
+       rcu_read_lock();
        session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id));
        if (!session) {
                DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`",
@@ -320,7 +321,7 @@ static int action_executor_start_session_handler(
 
        session_lock(session);
        if (session->destroyed) {
-               DBG("Session '%s' with id = %" PRIu64 " is flagged as destroyed. Skipping: action = '%s', trigger = '%s'",
+               DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`",
                                session->name, session->id,
                                get_action_name(action),
                                get_trigger_name(work_item->trigger));
@@ -353,6 +354,7 @@ error_unlock_session:
        session_unlock(session);
        session_put(session);
 error_unlock_list:
+       rcu_read_unlock();
        session_unlock_list();
 end:
        return ret;
@@ -384,7 +386,7 @@ static int action_executor_stop_session_handler(
         * existed. If not, skip the action altogether.
         */
        if (!item->context.session_id.is_set) {
-               DBG("Session `%s` was not present at the moment the work item was enqueued for %s` action of trigger `%s`",
+               DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`",
                                session_name, get_action_name(action),
                                get_trigger_name(work_item->trigger));
                lttng_action_increase_execution_failure_count(action);
@@ -392,6 +394,7 @@ static int action_executor_stop_session_handler(
        }
 
        session_lock_list();
+       rcu_read_lock();
        session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id));
        if (!session) {
                DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`",
@@ -403,7 +406,7 @@ static int action_executor_stop_session_handler(
 
        session_lock(session);
        if (session->destroyed) {
-               DBG("Session '%s' with id = %" PRIu64 " is flagged as destroyed. Skipping: action = '%s', trigger = '%s'",
+               DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`",
                                session->name, session->id,
                                get_action_name(action),
                                get_trigger_name(work_item->trigger));
@@ -436,6 +439,7 @@ error_unlock_session:
        session_unlock(session);
        session_put(session);
 error_unlock_list:
+       rcu_read_unlock();
        session_unlock_list();
 end:
        return ret;
@@ -467,7 +471,7 @@ static int action_executor_rotate_session_handler(
         * existed. If not, skip the action altogether.
         */
        if (!item->context.session_id.is_set) {
-               DBG("Session `%s` was not present at the moment the work item was enqueued for %s` action of trigger `%s`",
+               DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`",
                                session_name, get_action_name(action),
                                get_trigger_name(work_item->trigger));
                lttng_action_increase_execution_failure_count(action);
@@ -475,6 +479,7 @@ static int action_executor_rotate_session_handler(
        }
 
        session_lock_list();
+       rcu_read_lock();
        session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id));
        if (!session) {
                DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`",
@@ -486,7 +491,7 @@ static int action_executor_rotate_session_handler(
 
        session_lock(session);
        if (session->destroyed) {
-               DBG("Session '%s' with id = %" PRIu64 " is flagged as destroyed. Skipping: action = '%s', trigger = '%s'",
+               DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`",
                                session->name, session->id,
                                get_action_name(action),
                                get_trigger_name(work_item->trigger));
@@ -526,6 +531,7 @@ error_unlock_session:
        session_unlock(session);
        session_put(session);
 error_unlock_list:
+       rcu_read_unlock();
        session_unlock_list();
 end:
        return ret;
@@ -553,7 +559,7 @@ static int action_executor_snapshot_session_handler(
         * existed. If not, skip the action altogether.
         */
        if (!item->context.session_id.is_set) {
-               DBG("Session was not present at the moment the work item was enqueued for %s` action of trigger `%s`",
+               DBG("Session was not present at the moment the work item was enqueued for `%s` action of trigger `%s`",
                                get_action_name(action),
                                get_trigger_name(work_item->trigger));
                lttng_action_increase_execution_failure_count(action);
@@ -580,6 +586,7 @@ static int action_executor_snapshot_session_handler(
        }
 
        session_lock_list();
+       rcu_read_lock();
        session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id));
        if (!session) {
                DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`",
@@ -591,7 +598,7 @@ static int action_executor_snapshot_session_handler(
 
        session_lock(session);
        if (session->destroyed) {
-               DBG("Session '%s' with id = %" PRIu64 " is flagged as destroyed. Skipping: action = '%s', trigger = '%s'",
+               DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`",
                                session->name, session->id,
                                get_action_name(action),
                                get_trigger_name(work_item->trigger));
@@ -620,6 +627,7 @@ error_unlock_session:
        session_unlock(session);
        session_put(session);
 error_unlock_list:
+       rcu_read_unlock();
        session_unlock_list();
 end:
        return ret;
@@ -752,7 +760,7 @@ static void *action_executor_thread(void *_data)
                                        work_item->trigger, &trigger_owner_uid);
                        LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
 
-                       DBG("Work item skipped since the associated trigger is no longer registered: work item id = %" PRIu64 ", trigger name = '%s', trigger owner uid = %d",
+                       DBG("Work item skipped since the associated trigger is no longer registered: work item id = %" PRIu64 ", trigger name = `%s`, trigger owner uid = %d",
                                        work_item->id, trigger_name,
                                        (int) trigger_owner_uid);
                        ret = 0;
@@ -872,6 +880,7 @@ enum action_executor_status action_executor_enqueue_trigger(
        bool signal = false;
 
        LTTNG_ASSERT(trigger);
+       ASSERT_RCU_READ_LOCKED();
 
        pthread_mutex_lock(&executor->work.lock);
        /* Check for queue overflow. */
@@ -885,7 +894,7 @@ enum action_executor_status action_executor_enqueue_trigger(
 
        work_item = (action_work_item *) zmalloc(sizeof(*work_item));
        if (!work_item) {
-               PERROR("Failed to allocate action executor work item: trigger name = '%s'",
+               PERROR("Failed to allocate action executor work item: trigger name = `%s`",
                                get_trigger_name(trigger));
                executor_status = ACTION_EXECUTOR_STATUS_ERROR;
                goto error_unlock;