X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread.c;h=8d69ef7c45919448d227056ad82880e21a476e48;hp=4ce38e180e106986ae630a0c85483e93568405a3;hb=1f4962443f25c371e4b54e97f9eb867d67cbf88e;hpb=ea9a44f03f3f6e144b5f7f312eee2a5f7a849ecb

diff --git a/src/bin/lttng-sessiond/notification-thread.c b/src/bin/lttng-sessiond/notification-thread.c
index 4ce38e180..8d69ef7c4 100644
--- a/src/bin/lttng-sessiond/notification-thread.c
+++ b/src/bin/lttng-sessiond/notification-thread.c
@@ -37,6 +37,7 @@
 #include "notification-thread-commands.h"
 #include "lttng-sessiond.h"
 #include "health-sessiond.h"
+#include "thread.h"
 
 #include <urcu.h>
 #include <urcu/list.h>
@@ -56,6 +57,7 @@ void notification_thread_handle_destroy(
 
 	assert(cds_list_empty(&handle->cmd_queue.list));
 	pthread_mutex_destroy(&handle->cmd_queue.lock);
+	sem_destroy(&handle->ready);
 
 	if (handle->cmd_queue.event_pipe) {
 		lttng_pipe_destroy(handle->cmd_queue.event_pipe);
@@ -85,8 +87,7 @@ end:
 struct notification_thread_handle *notification_thread_handle_create(
 		struct lttng_pipe *ust32_channel_monitor_pipe,
 		struct lttng_pipe *ust64_channel_monitor_pipe,
-		struct lttng_pipe *kernel_channel_monitor_pipe,
-		sem_t *notification_thread_ready)
+		struct lttng_pipe *kernel_channel_monitor_pipe)
 {
 	int ret;
 	struct notification_thread_handle *handle;
@@ -97,6 +98,8 @@ struct notification_thread_handle *notification_thread_handle_create(
 		goto end;
 	}
 
+	sem_init(&handle->ready, 0, 0);
+
 	event_pipe = lttng_pipe_open(FD_CLOEXEC);
 	if (!event_pipe) {
 		ERR("event_pipe creation");
@@ -142,7 +145,6 @@ struct notification_thread_handle *notification_thread_handle_create(
 	} else {
 		handle->channel_monitoring_pipes.kernel_consumer = -1;
 	}
-	handle->notification_thread_ready = notification_thread_ready;
 end:
 	return handle;
 error:
@@ -170,7 +172,7 @@ char *get_notification_channel_sock_path(void)
 			goto error;
 		}
 	} else {
-		char *home_path = utils_get_home_dir();
+		const char *home_path = utils_get_home_dir();
 
 		if (!home_path) {
 			ERR("Can't get HOME directory for socket creation");
@@ -237,8 +239,16 @@ int notification_channel_socket_create(void)
 	}
 
 	if (getuid() == 0) {
-		ret = chown(sock_path, 0,
-				utils_get_group_id(config.tracing_group_name.value));
+		gid_t gid;
+
+		ret =  utils_get_group_id(config.tracing_group_name.value, true,
+				&gid);
+		if (ret) {
+			/* Default to root group. */
+			gid = 0;
+		}
+
+		ret = chown(sock_path, 0, gid);
 		if (ret) {
 			ERR("Failed to set the notification channel socket's group");
 			ret = -1;
@@ -374,6 +384,21 @@ void fini_thread_state(struct notification_thread_state *state)
 	lttng_poll_clean(&state->events);
 }
 
+static
+void mark_thread_as_ready(struct notification_thread_handle *handle)
+{
+	DBG("Marking notification thread as ready");
+	sem_post(&handle->ready);
+}
+
+static
+void wait_until_thread_is_ready(struct notification_thread_handle *handle)
+{
+	DBG("Waiting for notification thread to be ready");
+	sem_wait(&handle->ready);
+	DBG("Notification thread is ready");
+}
+
 static
 int init_thread_state(struct notification_thread_handle *handle,
 		struct notification_thread_state *state)
@@ -448,7 +473,7 @@ int init_thread_state(struct notification_thread_handle *handle,
 	if (!state->triggers_ht) {
 		goto error;
 	}
-	sem_post(handle->notification_thread_ready);
+	mark_thread_as_ready(handle);
 end:
 	return 0;
 error:
@@ -496,6 +521,7 @@ end:
  * This thread services notification channel clients and commands received
  * from various lttng-sessiond components over a command queue.
  */
+static
 void *thread_notification(void *data)
 {
 	int ret;
@@ -504,15 +530,15 @@ void *thread_notification(void *data)
 
 	DBG("[notification-thread] Started notification thread");
 
+	health_register(health_sessiond, HEALTH_SESSIOND_TYPE_NOTIFICATION);
+	rcu_register_thread();
+	rcu_thread_online();
+
 	if (!handle) {
 		ERR("[notification-thread] Invalid thread context provided");
 		goto end;
 	}
 
-	rcu_register_thread();
-	rcu_thread_online();
-
-	health_register(health_sessiond, HEALTH_SESSIOND_TYPE_NOTIFICATION);
 	health_code_update();
 
 	ret = init_thread_state(handle, &state);
@@ -520,9 +546,6 @@ void *thread_notification(void *data)
 		goto end;
 	}
 
-	/* Ready to handle client connections. */
-	sessiond_notify_ready();
-
 	while (true) {
 		int fd_count, i;
 
@@ -547,9 +570,6 @@ void *thread_notification(void *data)
 			int fd = LTTNG_POLL_GETFD(&state.events, i);
 			uint32_t revents = LTTNG_POLL_GETEV(&state.events, i);
 
-			if (!revents) {
-				continue;
-			}
 			DBG("[notification-thread] Handling fd (%i) activity (%u)", fd, revents);
 
 			if (fd == state.notification_channel_socket) {
@@ -622,9 +642,43 @@ void *thread_notification(void *data)
 exit:
 error:
 	fini_thread_state(&state);
-	health_unregister(health_sessiond);
+end:
 	rcu_thread_offline();
 	rcu_unregister_thread();
-end:
+	health_unregister(health_sessiond);
+	return NULL;
+}
+
+static
+bool shutdown_notification_thread(void *thread_data)
+{
+	struct notification_thread_handle *handle = thread_data;
+
+	notification_thread_command_quit(handle);
+	return true;
+}
+
+struct lttng_thread *launch_notification_thread(
+		struct notification_thread_handle *handle)
+{
+	struct lttng_thread *thread;
+
+	thread = lttng_thread_create("Notification",
+			thread_notification,
+			shutdown_notification_thread,
+			NULL,
+			handle);
+	if (!thread) {
+		goto error;
+	}
+
+	/*
+	 * Wait for the thread to be marked as "ready" before returning
+	 * as other subsystems depend on the notification subsystem
+	 * (e.g. rotation thread).
+	 */
+	wait_until_thread_is_ready(handle);
+	return thread;
+error:
 	return NULL;
 }