X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Faction-executor.cpp;h=34d3b7130f0a713b089bff4461cab34c9ce36445;hb=c9753f7250f33184a1859088a691291f37161f25;hp=cc7834f2745ca6e58d8299dd7c649fe68ecc0aaa;hpb=7966af5763c4aaca39df9bbfa9277ff15715c720;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/action-executor.cpp b/src/bin/lttng-sessiond/action-executor.cpp
index cc7834f27..34d3b7130 100644
--- a/src/bin/lttng-sessiond/action-executor.cpp
+++ b/src/bin/lttng-sessiond/action-executor.cpp
@@ -301,42 +301,35 @@ 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);
-		ret = 0;
 		goto end;
 	}
 
 	session_lock_list();
-	session = session_find_by_name(session_name);
+	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`",
 				session_name, get_action_name(action),
 				get_trigger_name(work_item->trigger));
+		lttng_action_increase_execution_failure_count(action);
 		goto error_unlock_list;
 	}
 
-	/*
-	 * Check if the session id is the same as when the work item was
-	 * enqueued.
-	 */
-	if (session->id != LTTNG_OPTIONAL_GET(item->context.session_id)) {
-		DBG("Session id for session `%s` (id: %" PRIu64
-				" is not the same that was sampled (id: %" PRIu64
-				" at the moment the work item was enqueued for %s` action of trigger `%s`",
-				session_name, session->id,
-				LTTNG_OPTIONAL_GET(item->context.session_id),
+	session_lock(session);
+	if (session->destroyed) {
+		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));
-		ret = 0;
-		goto error_unlock_list;
+		goto error_unlock_session;
 	}
 
-	session_lock(session);
 	if (!is_trigger_allowed_for_session(work_item->trigger, session)) {
-		goto error_dispose_session;
+		goto error_unlock_session;
 	}
 
 	cmd_ret = (lttng_error_code) cmd_start_trace(session);
@@ -357,10 +350,11 @@ static int action_executor_start_session_handler(
 		break;
 	}
 
-error_dispose_session:
+error_unlock_session:
 	session_unlock(session);
 	session_put(session);
 error_unlock_list:
+	rcu_read_unlock();
 	session_unlock_list();
 end:
 	return ret;
@@ -392,16 +386,16 @@ 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);
-		ret = 0;
 		goto end;
 	}
 
 	session_lock_list();
-	session = session_find_by_name(session_name);
+	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`",
 				session_name, get_action_name(action),
@@ -410,25 +404,17 @@ static int action_executor_stop_session_handler(
 		goto error_unlock_list;
 	}
 
-	/*
-	 * Check if the session id is the same as when the work item was
-	 * enqueued
-	 */
-	if (session->id != LTTNG_OPTIONAL_GET(item->context.session_id)) {
-		DBG("Session id for session `%s` (id: %" PRIu64
-				" is not the same that was sampled (id: %" PRIu64
-				" at the moment the work item was enqueued for %s` action of trigger `%s`",
-				session_name, session->id,
-				LTTNG_OPTIONAL_GET(item->context.session_id),
+	session_lock(session);
+	if (session->destroyed) {
+		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));
-		ret = 0;
-		goto error_unlock_list;
+		goto error_unlock_session;
 	}
 
-	session_lock(session);
 	if (!is_trigger_allowed_for_session(work_item->trigger, session)) {
-		goto error_dispose_session;
+		goto error_unlock_session;
 	}
 
 	cmd_ret = (lttng_error_code) cmd_stop_trace(session);
@@ -449,10 +435,11 @@ static int action_executor_stop_session_handler(
 		break;
 	}
 
-error_dispose_session:
+error_unlock_session:
 	session_unlock(session);
 	session_put(session);
 error_unlock_list:
+	rcu_read_unlock();
 	session_unlock_list();
 end:
 	return ret;
@@ -484,16 +471,16 @@ 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);
-		ret = 0;
 		goto end;
 	}
 
 	session_lock_list();
-	session = session_find_by_name(session_name);
+	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`",
 				session_name, get_action_name(action),
@@ -502,25 +489,17 @@ static int action_executor_rotate_session_handler(
 		goto error_unlock_list;
 	}
 
-	/*
-	 * Check if the session id is the same as when the work item was
-	 * enqueued.
-	 */
-	if (session->id != LTTNG_OPTIONAL_GET(item->context.session_id)) {
-		DBG("Session id for session `%s` (id: %" PRIu64
-		    " is not the same that was sampled (id: %" PRIu64
-		    " at the moment the work item was enqueued for %s` action of trigger `%s`",
-				session_name, session->id,
-				LTTNG_OPTIONAL_GET(item->context.session_id),
+	session_lock(session);
+	if (session->destroyed) {
+		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));
-		ret = 0;
-		goto error_unlock_list;
+		goto error_unlock_session;
 	}
 
-	session_lock(session);
 	if (!is_trigger_allowed_for_session(work_item->trigger, session)) {
-		goto error_dispose_session;
+		goto error_unlock_session;
 	}
 
 	cmd_ret = (lttng_error_code) cmd_rotate_session(session, NULL, false,
@@ -548,10 +527,11 @@ static int action_executor_rotate_session_handler(
 		break;
 	}
 
-error_dispose_session:
+error_unlock_session:
 	session_unlock(session);
 	session_put(session);
 error_unlock_list:
+	rcu_read_unlock();
 	session_unlock_list();
 end:
 	return ret;
@@ -579,11 +559,10 @@ 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);
-		ret = 0;
 		goto end;
 	}
 
@@ -607,7 +586,8 @@ static int action_executor_snapshot_session_handler(
 	}
 
 	session_lock_list();
-	session = session_find_by_name(session_name);
+	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`",
 				session_name, get_action_name(action),
@@ -616,25 +596,17 @@ static int action_executor_snapshot_session_handler(
 		goto error_unlock_list;
 	}
 
-	/*
-	 * Check if the session id is the same as when the work item was
-	 * enqueued.
-	 */
-	if (session->id != LTTNG_OPTIONAL_GET(item->context.session_id)) {
-		DBG("Session id for session `%s` (id: %" PRIu64
-		    " is not the same that was sampled (id: %" PRIu64
-		    " at the moment the work item was enqueued for %s` action of trigger `%s`",
-				session_name, session->id,
-				LTTNG_OPTIONAL_GET(item->context.session_id),
+	session_lock(session);
+	if (session->destroyed) {
+		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));
-		ret = 0;
-		goto error_unlock_list;
+		goto error_unlock_session;
 	}
 
-	session_lock(session);
 	if (!is_trigger_allowed_for_session(work_item->trigger, session)) {
-		goto error_dispose_session;
+		goto error_unlock_session;
 	}
 
 	cmd_ret = (lttng_error_code) cmd_snapshot_record(session, snapshot_output, 0);
@@ -651,10 +623,11 @@ static int action_executor_snapshot_session_handler(
 		break;
 	}
 
-error_dispose_session:
+error_unlock_session:
 	session_unlock(session);
 	session_put(session);
 error_unlock_list:
+	rcu_read_unlock();
 	session_unlock_list();
 end:
 	return ret;
@@ -787,7 +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;
@@ -907,6 +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. */
@@ -920,7 +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;