X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-relayd%2Fmain.c;h=62e149ed2cbdaf574968cbbe93659c48c8907db3;hb=c7759e6a503ebd197dd6a84de0eeaa52fbd0e81f;hp=7e5733ec8c3253432bd61dbac17b0968fefef21a;hpb=a4baae1b0463bc4ce65c2a458c4a941e7fabc594;p=lttng-tools.git

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index 7e5733ec8..62e149ed2 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -45,6 +45,7 @@
 #include <common/compat/poll.h>
 #include <common/compat/socket.h>
 #include <common/defaults.h>
+#include <common/daemonize.h>
 #include <common/futex.h>
 #include <common/sessiond-comm/sessiond-comm.h>
 #include <common/sessiond-comm/inet.h>
@@ -63,7 +64,17 @@
 
 /* command line options */
 char *opt_output_path;
-static int opt_daemon;
+static int opt_daemon, opt_background;
+
+/*
+ * We need to wait for listener and live listener threads, as well as
+ * health check thread, before being ready to signal readiness.
+ */
+#define NR_LTTNG_RELAY_READY	3
+static int lttng_relay_ready = NR_LTTNG_RELAY_READY;
+static int recv_child_signal;	/* Set to 1 when a SIGUSR1 signal is received. */
+static pid_t child_ppid;	/* Internal parent PID use with daemonize. */
+
 static struct lttng_uri *control_uri;
 static struct lttng_uri *data_uri;
 static struct lttng_uri *live_uri;
@@ -131,6 +142,7 @@ static struct option long_options[] = {
 	{ "data-port", 1, 0, 'D', },
 	{ "live-port", 1, 0, 'L', },
 	{ "daemonize", 0, 0, 'd', },
+	{ "background", 0, 0, 'b', },
 	{ "group", 1, 0, 'g', },
 	{ "help", 0, 0, 'h', },
 	{ "output", 1, 0, 'o', },
@@ -150,6 +162,7 @@ void usage(void)
 	fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 	fprintf(stderr, "  -h, --help                Display this usage.\n");
 	fprintf(stderr, "  -d, --daemonize           Start as a daemon.\n");
+	fprintf(stderr, "  -b, --background          Start as a daemon, keeping console open.\n");
 	fprintf(stderr, "  -C, --control-port URL    Control port listening.\n");
 	fprintf(stderr, "  -D, --data-port URL       Data port listening.\n");
 	fprintf(stderr, "  -L, --live-port URL       Live view port listening.\n");
@@ -210,6 +223,9 @@ int set_option(int opt, const char *arg, const char *optname)
 	case 'd':
 		opt_daemon = 1;
 		break;
+	case 'b':
+		opt_background = 1;
+		break;
 	case 'g':
 		tracing_group_name = strdup(arg);
 		tracing_group_name_override = 1;
@@ -504,6 +520,9 @@ void sighandler(int sig)
 		DBG("SIGTERM caught");
 		stop_threads();
 		break;
+	case SIGUSR1:
+		CMM_STORE_SHARED(recv_child_signal, 1);
+		break;
 	default:
 		break;
 	}
@@ -543,11 +562,26 @@ int set_signal_handler(void)
 		return ret;
 	}
 
-	DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
+	if ((ret = sigaction(SIGUSR1, &sa, NULL)) < 0) {
+		PERROR("sigaction");
+		return ret;
+	}
+
+	DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE and SIGINT");
 
 	return ret;
 }
 
+void lttng_relay_notify_ready(void)
+{
+	/* Notify the parent of the fork() process that we are ready. */
+	if (opt_daemon || opt_background) {
+		if (uatomic_sub_return(&lttng_relay_ready, 1) == 0) {
+			kill(child_ppid, SIGUSR1);
+		}
+	}
+}
+
 /*
  * Init thread quit pipe.
  *
@@ -582,7 +616,7 @@ int create_thread_poll_set(struct lttng_poll_event *events, int size)
 	}
 
 	/* Add quit pipe */
-	ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
+	ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN | LPOLLERR);
 	if (ret < 0) {
 		goto error;
 	}
@@ -717,6 +751,8 @@ void *relay_thread_listener(void *data)
 		goto error_poll_add;
 	}
 
+	lttng_relay_notify_ready();
+
 	while (1) {
 		health_code_update();
 
@@ -1166,18 +1202,10 @@ void set_viewer_ready_flag(struct relay_command *cmd)
 			 * Stream is most probably being cleaned up by the data thread thus
 			 * simply continue to the next one.
 			 */
+			rcu_read_unlock();
 			continue;
 		}
 
-		/*
-		 * If any of the streams in the list doesn't have a ctf_trace assigned,
-		 * it means that we never received the metadata stream, so we have to
-		 * wait until it arrives to make the streams available to the viewer.
-		 */
-		if (!stream->ctf_trace) {
-			goto end;
-		}
-
 		stream->viewer_ready = 1;
 		rcu_read_unlock();
 
@@ -1186,7 +1214,6 @@ void set_viewer_ready_flag(struct relay_command *cmd)
 		free(node);
 	}
 
-end:
 	return;
 }
 
@@ -1308,7 +1335,11 @@ int relay_add_stream(struct lttcomm_relayd_hdr *recv_hdr,
 	 * stream message is received, this list is emptied and streams are set
 	 * with the viewer ready flag.
 	 */
-	queue_stream_handle(stream->stream_handle, cmd);
+	if (stream->metadata_flag) {
+		stream->viewer_ready = 1;
+	} else {
+		queue_stream_handle(stream->stream_handle, cmd);
+	}
 
 	lttng_ht_node_init_ulong(&stream->stream_n,
 			(unsigned long) stream->stream_handle);
@@ -2822,11 +2853,6 @@ int main(int argc, char **argv)
 	void *status;
 	struct relay_local_data *relay_ctx;
 
-	/* Create thread quit pipe */
-	if ((ret = init_thread_quit_pipe()) < 0) {
-		goto error;
-	}
-
 	/* Parse arguments */
 	progname = argv[0];
 	if ((ret = set_options(argc, argv)) < 0) {
@@ -2852,12 +2878,28 @@ int main(int argc, char **argv)
 	}
 
 	/* Daemonize */
-	if (opt_daemon) {
-		ret = daemon(0, 0);
+	if (opt_daemon || opt_background) {
+		int i;
+
+		ret = lttng_daemonize(&child_ppid, &recv_child_signal,
+			!opt_background);
 		if (ret < 0) {
-			PERROR("daemon");
 			goto exit;
 		}
+
+		/*
+		 * We are in the child. Make sure all other file
+		 * descriptors are closed, in case we are called with
+		 * more opened file descriptors than the standard ones.
+		 */
+		for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
+			(void) close(i);
+		}
+	}
+
+	/* Create thread quit pipe */
+	if ((ret = init_thread_quit_pipe()) < 0) {
+		goto error;
 	}
 
 	/* We need those values for the file/dir creation. */
@@ -2886,6 +2928,7 @@ int main(int argc, char **argv)
 
 	/* Initialize communication library */
 	lttcomm_init();
+	lttcomm_inet_init();
 
 	relay_ctx = zmalloc(sizeof(struct relay_local_data));
 	if (!relay_ctx) {