X-Git-Url: https://git.lttng.org/?p=lttngtop.git;a=blobdiff_plain;f=src%2Flttngtop.c;h=d1b36a3e31e17ac20d7493c7e7c0e1849912747b;hp=9ac8d39c1c9f8c262a9fea039de0c7c9b663e339;hb=f16e36fc0e460e58e327de6baaec29e90c3e3c93;hpb=30b646c4e7aab1e1bee8fef60619a61bd80bedad

diff --git a/src/lttngtop.c b/src/lttngtop.c
index 9ac8d39..d1b36a3 100644
--- a/src/lttngtop.c
+++ b/src/lttngtop.c
@@ -51,7 +51,10 @@
 #define DEFAULT_FILE_ARRAY_SIZE 1
 
 const char *opt_input_path;
-int opt_textdump;
+static int opt_textdump;
+static int opt_child;
+
+int quit = 0;
 
 struct lttngtop *copy;
 pthread_t display_thread;
@@ -59,7 +62,6 @@ pthread_t timer_thread;
 
 unsigned long refresh_display = 1 * NSEC_PER_SEC;
 unsigned long last_display_update = 0;
-int quit = 0;
 
 /* list of FDs available for being read with snapshots */
 struct mmap_stream_list mmap_list;
@@ -69,28 +71,54 @@ struct lttng_consumer_local_data *ctx = NULL;
 /* list of snapshots currently not consumed */
 GPtrArray *available_snapshots;
 sem_t metadata_available;
-FILE *metadata_fp;
-int trace_opened = 0;
-int metadata_ready = 0;
+int reload_trace = 0;
+
+int last_textdump_print_newline = 1;
 
 enum {
 	OPT_NONE = 0,
 	OPT_HELP,
 	OPT_TEXTDUMP,
+	OPT_PID,
+	OPT_CHILD,
+	OPT_HOSTNAME,
+	OPT_KPROBES,
 };
 
 static struct poptOption long_options[] = {
 	/* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
 	{ "help", 'h', POPT_ARG_NONE, NULL, OPT_HELP, NULL, NULL },
 	{ "textdump", 't', POPT_ARG_NONE, NULL, OPT_TEXTDUMP, NULL, NULL },
+	{ "child", 'f', POPT_ARG_NONE, NULL, OPT_CHILD, NULL, NULL },
+	{ "pid", 'p', POPT_ARG_STRING, &opt_tid, OPT_PID, NULL, NULL },
+	{ "hostname", 'n', POPT_ARG_STRING, &opt_hostname, OPT_HOSTNAME, NULL, NULL },
+	{ "kprobes", 'k', POPT_ARG_STRING, &opt_kprobes, OPT_KPROBES, NULL, NULL },
 	{ NULL, 0, 0, NULL, 0, NULL, NULL },
 };
 
+static void handle_textdump_sigterm(int signal)
+{
+	quit = 1;
+	lttng_destroy_session("test");
+}
+
 void *refresh_thread(void *p)
 {
+	struct mmap_stream *mmap_info;
+
 	while (1) {
-		if (quit)
-			return NULL;
+		if (quit) {
+			sem_post(&pause_sem);
+			sem_post(&timer);
+			sem_post(&end_trace_sem);
+			sem_post(&goodtodisplay);
+			sem_post(&goodtoupdate);
+			pthread_exit(0);
+		}
+		if (!opt_input_path) {
+			bt_list_for_each_entry(mmap_info, &mmap_list.head, list)
+				helper_kernctl_buffer_flush(mmap_info->fd);
+		}
 		sem_wait(&pause_sem);
 		sem_post(&pause_sem);
 		sem_post(&timer);
@@ -114,16 +142,49 @@ void *ncurses_display(void *p)
 		sem_wait(&goodtodisplay);
 		sem_wait(&pause_sem);
 
+		if (quit) {
+			sem_post(&pause_sem);
+			sem_post(&timer);
+			reset_ncurses();
+			pthread_exit(0);
+		}
+
 		copy = g_ptr_array_index(copies, current_display_index);
 		assert(copy);
 		display(current_display_index++);
 
 		sem_post(&goodtoupdate);
 		sem_post(&pause_sem);
+	}
+}
 
-		if (quit) {
-			reset_ncurses();
-			pthread_exit(0);
+void print_fields(struct bt_ctf_event *event)
+{
+	unsigned int cnt, i;
+	const struct definition *const * list;
+	const struct definition *scope;
+	enum ctf_type_id type;
+	const char *str;
+
+	scope = bt_ctf_get_top_level_scope(event, BT_EVENT_FIELDS);
+
+	bt_ctf_get_field_list(event, scope, &list, &cnt);
+	for (i = 0; i < cnt; i++) {
+		if (i != 0)
+			printf(", ");
+		printf("%s = ", bt_ctf_field_name(list[i]));
+		type = bt_ctf_field_type(list[i]);
+		if (type == CTF_TYPE_INTEGER) {
+			if (bt_ctf_get_int_signedness(list[i]) == 0)
+				printf("%" PRIu64 "", bt_ctf_get_uint64(list[i]));
+			else
+				printf("%" PRId64 "", bt_ctf_get_int64(list[i]));
+		} else if (type == CTF_TYPE_STRING) {
+			printf("%s", bt_ctf_get_string(list[i]));
+		} else if (type == CTF_TYPE_ARRAY) {
+			str = bt_ctf_get_char_array(list[i]);
+			if (!bt_ctf_field_get_error() && str)
+				printf("%s", str);
 		}
 	}
 }
@@ -137,16 +198,78 @@ enum bt_cb_ret print_timestamp(struct bt_ctf_event *call_data, void *private_dat
 	unsigned long timestamp;
 	struct tm start;
 	uint64_t ts_nsec_start;
-
+	int pid, cpu_id;
+	int64_t syscall_ret;
+	const struct definition *scope;
+	const char *hostname, *procname;
 
 	timestamp = bt_ctf_get_timestamp(call_data);
 
 	start = format_timestamp(timestamp);
 	ts_nsec_start = timestamp % NSEC_PER_SEC;
 
-	printf("%02d:%02d:%02d.%09" PRIu64 " %s\n", start.tm_hour,
-			start.tm_min, start.tm_sec, ts_nsec_start,
-			bt_ctf_event_name(call_data));
+	pid = get_context_pid(call_data);
+	if (pid == -1ULL && opt_tid) {
+		goto error;
+	}
+	
+	hostname = get_context_hostname(call_data);
+	if (!opt_tid && (opt_hostname && !lookup_hostname_list(hostname)))
+		goto end;
+	if (!opt_hostname && (opt_tid && !lookup_tid_list(pid)))
+		goto end;
+	if ((opt_tid && !lookup_tid_list(pid)) &&
+			(opt_hostname && !lookup_hostname_list(hostname)))
+		goto end;
+
+	cpu_id = get_cpu_id(call_data);
+	procname = get_context_comm(call_data);
+
+	if ((strcmp(bt_ctf_event_name(call_data), "exit_syscall") == 0) &&
+			!last_textdump_print_newline) {
+		scope = bt_ctf_get_top_level_scope(call_data,
+				BT_EVENT_FIELDS);
+		syscall_ret = bt_ctf_get_int64(bt_ctf_get_field(call_data,
+					scope, "_ret"));
+		printf("= %ld\n", syscall_ret);
+		last_textdump_print_newline = 1;
+	} else {
+		/* we might have lost the exit_syscall event, so need to
+		 * print the newline in this case */
+		if (last_textdump_print_newline == 0)
+			printf("\n");
+		printf("%02d:%02d:%02d.%09" PRIu64 " (%s) (cpu %d) [%s (%d)] %s (",
+				start.tm_hour, start.tm_min, start.tm_sec,
+				ts_nsec_start, hostname, cpu_id, procname, pid,
+				bt_ctf_event_name(call_data));
+		print_fields(call_data);
+		printf(") ");
+		if (strncmp(bt_ctf_event_name(call_data), "sys_", 4) != 0) {
+			printf("\n");
+			last_textdump_print_newline = 1;
+		} else {
+			last_textdump_print_newline = 0;
+		}
+	}
+
+end:
+	return BT_CB_OK;
+error:
+	return BT_CB_ERROR_STOP;
+}
+
+enum bt_cb_ret handle_kprobes(struct bt_ctf_event *call_data, void *private_data)
+{
+	int i;
+	struct kprobes *kprobe;
+
+	/* for kprobes */
+	for (i = 0; i < lttngtop.kprobes_table->len; i++) {
+		kprobe = g_ptr_array_index(lttngtop.kprobes_table, i);
+		if (strcmp(bt_ctf_event_name(call_data), kprobe->probe_name) == 0) {
+			kprobe->count++;
+		}
+	}
 
 	return BT_CB_OK;
 }
@@ -285,8 +408,8 @@ void update_perf_counter(struct processtop *proc, const struct bt_ctf_event *eve
 enum bt_cb_ret fix_process_table(struct bt_ctf_event *call_data,
 		void *private_data)
 {
-	int pid, tid, ppid;
-	char *comm;
+	int pid, tid, ppid, vpid, vtid, vppid;
+	char *comm, *hostname;
 	struct processtop *parent, *child;
 	unsigned long timestamp;
 
@@ -298,6 +421,7 @@ enum bt_cb_ret fix_process_table(struct bt_ctf_event *call_data,
 	if (pid == -1ULL) {
 		goto error;
 	}
+
 	tid = get_context_tid(call_data);
 	if (tid == -1ULL) {
 		goto error;
@@ -306,23 +430,40 @@ enum bt_cb_ret fix_process_table(struct bt_ctf_event *call_data,
 	if (ppid == -1ULL) {
 		goto error;
 	}
+	vpid = get_context_vpid(call_data);
+	if (pid == -1ULL) {
+		vpid = -1;
+	}
+	vtid = get_context_vtid(call_data);
+	if (tid == -1ULL) {
+		vtid = -1;
+	}
+	vppid = get_context_vppid(call_data);
+	if (ppid == -1ULL) {
+		vppid = -1;
+	}
 	comm = get_context_comm(call_data);
 	if (!comm) {
 		goto error;
 	}
+	/* optional */
+	hostname = get_context_hostname(call_data);
 
 	/* find or create the current process */
 	child = find_process_tid(&lttngtop, tid, comm);
 	if (!child)
 		child = add_proc(&lttngtop, tid, comm, timestamp);
-	update_proc(child, pid, tid, ppid, comm);
+	if (!child)
+		goto end;
+	update_proc(child, pid, tid, ppid, vpid, vtid, vppid, comm, hostname);
 
 	if (pid != tid) {
 		/* find or create the parent */
 		parent = find_process_tid(&lttngtop, pid, comm);
 		if (!parent) {
 			parent = add_proc(&lttngtop, pid, comm, timestamp);
-			parent->pid = pid;
+			if (parent)
+				parent->pid = pid;
 		}
 
 		/* attach the parent to the current process */
@@ -332,6 +473,7 @@ enum bt_cb_ret fix_process_table(struct bt_ctf_event *call_data,
 
 	update_perf_counter(child, call_data);
 
+end:
 	return BT_CB_OK;
 
 error:
@@ -343,7 +485,6 @@ void init_lttngtop()
 	copies = g_ptr_array_new();
 	global_perf_liszt = g_hash_table_new(g_str_hash, g_str_equal);
 
-
 	sem_init(&goodtodisplay, 0, 0);
 	sem_init(&goodtoupdate, 0, 1);
 	sem_init(&timer, 0, 1);
@@ -366,7 +507,88 @@ void init_lttngtop()
 void usage(FILE *fp)
 {
 	fprintf(fp, "LTTngTop %s\n\n", VERSION);
-	fprintf(fp, "Usage : lttngtop /path/to/trace\n");
+	fprintf(fp, "Usage : lttngtop [OPTIONS] [TRACE]\n");
+	fprintf(fp, "  TRACE			Path to the trace to analyse (no trace path for live tracing)\n");
+	fprintf(fp, "  -h, --help               This help message\n");
+	fprintf(fp, "  -t, --textdump           Display live events in text-only\n");
+	fprintf(fp, "  -p, --pid                Comma-separated list of PIDs to display\n");
+	fprintf(fp, "  -f, --child              Follow threads associated with selected PIDs\n");
+	fprintf(fp, "  -n, --hostname           Comma-separated list of hostnames to display (require hostname context in trace)\n");
+}
+
+/*
+ * Parse probe options.
+ * Shamelessly stolen from lttng-tools :
+ * src/bin/lttng/commands/enable_events.c
+ */
+static struct kprobes *parse_probe_opts(char *opt)
+{
+	char s_hex[19];
+	char name[LTTNG_SYMBOL_NAME_LEN];
+	struct kprobes *kprobe;
+	int ret;
+
+	/*
+	kprobe->probe_addr = 0;
+	kprobe->probe_offset = 0;
+	asprintf(&kprobe->probe_name, "probe_sys_open");
+	asprintf(&kprobe->symbol_name, "sys_open");
+	*/
+
+	if (opt == NULL) {
+		kprobe = NULL;
+		goto end;
+	}
+
+	kprobe = g_new0(struct kprobes, 1);
+
+	/* Check for symbol+offset */
+	ret = sscanf(opt, "%[^'+']+%s", name, s_hex);
+	if (ret == 2) {
+		asprintf(&kprobe->probe_name, "probe_%s", name);
+		asprintf(&kprobe->symbol_name, "%s", name);
+
+		if (strlen(s_hex) == 0) {
+			fprintf(stderr, "Invalid probe offset %s", s_hex);
+			ret = -1;
+			goto end;
+		}
+		kprobe->probe_offset = strtoul(s_hex, NULL, 0);
+		kprobe->probe_addr = 0;
+		goto end;
+	}
+
+	/* Check for symbol */
+	if (isalpha(name[0])) {
+		ret = sscanf(opt, "%s", name);
+		if (ret == 1) {
+			asprintf(&kprobe->probe_name, "probe_%s", name);
+			asprintf(&kprobe->symbol_name, "%s", name);
+			kprobe->probe_offset = 0;
+			kprobe->probe_addr = 0;
+			goto end;
+		}
+	}
+
+	/* Check for address */
+	ret = sscanf(opt, "%s", s_hex);
+	if (ret > 0) {
+		if (strlen(s_hex) == 0) {
+			fprintf(stderr, "Invalid probe address %s", s_hex);
+			ret = -1;
+			goto end;
+		}
+		asprintf(&kprobe->probe_name, "probe_%s", s_hex);
+		kprobe->probe_offset = 0;
+		kprobe->probe_addr = strtoul(s_hex, NULL, 0);
+		goto end;
+	}
+
+	/* No match */
+	kprobe = NULL;
+
+end:
+	return kprobe;
 }
 
 /*
@@ -377,6 +599,8 @@ static int parse_options(int argc, char **argv)
 {
 	poptContext pc;
 	int opt, ret = 0;
+	char *tmp_str;
+	int *tid;
 
 	pc = poptGetContext(NULL, argc, (const char **) argv, long_options, 0);
 	poptReadDefaultConfig(pc, 0);
@@ -389,7 +613,53 @@ static int parse_options(int argc, char **argv)
 				goto end;
 			case OPT_TEXTDUMP:
 				opt_textdump = 1;
-				goto end;
+				break;
+			case OPT_CHILD:
+				opt_textdump = 1;
+				opt_child = 1;
+				break;
+			case OPT_PID:
+				tid_list = g_hash_table_new(g_str_hash,
+						g_str_equal);
+				tmp_str = strtok(opt_tid, ",");
+				while (tmp_str) {
+					tid = malloc(sizeof(int));
+					*tid = atoi(tmp_str);
+					g_hash_table_insert(tid_list,
+							(gpointer) tid, tid);
+					tmp_str = strtok(NULL, ",");
+				}
+				break;
+			case OPT_HOSTNAME:
+				hostname_list = g_hash_table_new(g_str_hash,
+						g_str_equal);
+				tmp_str = strtok(opt_hostname, ",");
+				while (tmp_str) {
+					char *new_str = strdup(tmp_str);
+					g_hash_table_insert(hostname_list,
+							(gpointer) new_str,
+							(gpointer) new_str);
+					tmp_str = strtok(NULL, ",");
+				}
+				break;
+			case OPT_KPROBES:
+				lttngtop.kprobes_table = g_ptr_array_new();
+				tmp_str = strtok(opt_kprobes, ",");
+				while (tmp_str) {
+					struct kprobes *kprobe;
+
+					kprobe = parse_probe_opts(tmp_str);
+					if (kprobe) {
+						g_ptr_array_add(
+							lttngtop.kprobes_table,
+							kprobe);
+					} else {
+						ret = -EINVAL;
+						goto end;
+					}
+					tmp_str = strtok(NULL, ",");
+				}
+				break;
 			default:
 				ret = -EINVAL;
 				goto end;
@@ -409,7 +679,9 @@ void iter_trace(struct bt_context *bt_ctx)
 {
 	struct bt_ctf_iter *iter;
 	struct bt_iter_pos begin_pos;
+	struct kprobes *kprobe;
 	const struct bt_ctf_event *event;
+	int i;
 	int ret = 0;
 
 	begin_pos.type = BT_SEEK_BEGIN;
@@ -464,9 +736,21 @@ void iter_trace(struct bt_context *bt_ctx)
 					"lttng_statedump_file_descriptor"),
 				NULL, 0, handle_statedump_file_descriptor,
 				NULL, NULL, NULL);
+
+		/* for kprobes */
+		for (i = 0; i < lttngtop.kprobes_table->len; i++) {
+			kprobe = g_ptr_array_index(lttngtop.kprobes_table, i);
+			bt_ctf_iter_add_callback(iter,
+					g_quark_from_static_string(
+						kprobe->probe_name),
+					NULL, 0, handle_kprobes,
+					NULL, NULL, NULL);
+		}
 	}
 
 	while ((event = bt_ctf_iter_read_event(iter)) != NULL) {
+		if (quit || reload_trace)
+			goto end_iter;
 		ret = bt_iter_next(bt_ctf_get_iter(iter));
 		if (ret < 0)
 			goto end_iter;
@@ -762,38 +1046,34 @@ int on_recv_fd(struct lttng_consumer_stream *kconsumerd_fd)
 		ret = 0;
 	}
 
+	reload_trace = 1;
+
 end:
 	return ret;
 }
 
-void *live_consume()
+void live_consume(struct bt_context **bt_ctx)
 {
-	struct bt_context *bt_ctx = NULL;
 	int ret;
+	FILE *metadata_fp;
 
-	if (!metadata_ready) {
-		sem_wait(&metadata_available);
-		if (access("/tmp/livesession/metadata", F_OK) != 0) {
-			fprintf(stderr,"no metadata\n");
-			return NULL;
-		}
-		metadata_ready = 1;
-		metadata_fp = fopen("/tmp/livesession/metadata", "r");
+	sem_wait(&metadata_available);
+	if (access("/tmp/livesession/kernel/metadata", F_OK) != 0) {
+		fprintf(stderr,"no metadata\n");
+		goto end;
 	}
+	metadata_fp = fopen("/tmp/livesession/kernel/metadata", "r");
 
-	if (!trace_opened) {
-		bt_ctx = bt_context_create();
-		ret = bt_context_add_trace(bt_ctx, NULL, "ctf",
-				lttngtop_ctf_packet_seek, &mmap_list, metadata_fp);
-		if (ret < 0) {
-			printf("Error adding trace\n");
-			return NULL;
-		}
-		trace_opened = 1;
+	*bt_ctx = bt_context_create();
+	ret = bt_context_add_trace(*bt_ctx, NULL, "ctf",
+			lttngtop_ctf_packet_seek, &mmap_list, metadata_fp);
+	if (ret < 0) {
+		printf("Error adding trace\n");
+		goto end;
 	}
-	iter_trace(bt_ctx);
 
-	return NULL;
+end:
+	return;
 }
 
 int setup_consumer(char *command_sock_path, pthread_t *threads,
@@ -829,7 +1109,35 @@ end:
 	return ret;
 }
 
-void *setup_live_tracing()
+int enable_kprobes(struct lttng_handle *handle, char *channel_name)
+{
+	struct lttng_event ev;
+	struct kprobes *kprobe;
+	int ret = 0;
+	int i;
+
+	for (i = 0; i < lttngtop.kprobes_table->len; i++) {
+		kprobe = g_ptr_array_index(lttngtop.kprobes_table, i);
+
+		memset(&ev, '\0', sizeof(struct lttng_event));
+		ev.type = LTTNG_EVENT_PROBE;
+		if (kprobe->symbol_name)
+			sprintf(ev.attr.probe.symbol_name, "%s", kprobe->symbol_name);
+		sprintf(ev.name, "%s", kprobe->probe_name);
+		ev.attr.probe.addr = kprobe->probe_addr;
+		ev.attr.probe.offset = kprobe->probe_offset;
+		if ((ret = lttng_enable_event(handle, &ev, channel_name)) < 0) {
+			fprintf(stderr,"error enabling kprobes : %s\n",
+					helper_lttcomm_get_readable_code(ret));
+			goto end;
+		}
+	}
+
+end:
+	return ret;
+}
+
+int setup_live_tracing()
 {
 	struct lttng_domain dom;
 	struct lttng_channel chan;
@@ -848,7 +1156,7 @@ void *setup_live_tracing()
 
 	if ((ret = setup_consumer(command_sock_path, threads, ctx)) < 0) {
 		fprintf(stderr,"error setting up consumer\n");
-		goto end;
+		goto error;
 	}
 
 	available_snapshots = g_ptr_array_new();
@@ -856,31 +1164,45 @@ void *setup_live_tracing()
 	/* setup the session */
 	dom.type = LTTNG_DOMAIN_KERNEL;
 
-	ret = system("rm -rf /tmp/livesession");
+	ret = unlink("/tmp/livesession");
 
 	lttng_destroy_session("test");
 	if ((ret = lttng_create_session("test", "/tmp/livesession")) < 0) {
 		fprintf(stderr,"error creating the session : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error;
 	}
 
 	if ((handle = lttng_create_handle("test", &dom)) == NULL) {
 		fprintf(stderr,"error creating handle\n");
-		goto end;
+		goto error_session;
+	}
+
+	/*
+	 * FIXME : need to let the
+	 * helper_lttng_consumer_thread_receive_fds create the
+	 * socket.
+	 * Cleaner solution ?
+	 */
+	while (access(command_sock_path, F_OK)) {
+		sleep(0.1);
 	}
 
 	if ((ret = lttng_register_consumer(handle, command_sock_path)) < 0) {
 		fprintf(stderr,"error registering consumer : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error_session;
 	}
 
 	strcpy(chan.name, channel_name);
 	chan.attr.overwrite = 0;
-//	chan.attr.subbuf_size = 32768;
-	chan.attr.subbuf_size = 1048576; /* 1MB */
-	chan.attr.num_subbuf = 4;
+	if (opt_tid && opt_textdump) {
+		chan.attr.subbuf_size = 32768;
+		chan.attr.num_subbuf = 8;
+	} else {
+		chan.attr.subbuf_size = 1048576; /* 1MB */
+		chan.attr.num_subbuf = 4;
+	}
 	chan.attr.switch_timer_interval = 0;
 	chan.attr.read_timer_interval = 200;
 	chan.attr.output = LTTNG_EVENT_MMAP;
@@ -888,7 +1210,7 @@ void *setup_live_tracing()
 	if ((ret = lttng_enable_channel(handle, &chan)) < 0) {
 		fprintf(stderr,"error creating channel : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error_session;
 	}
 
 	memset(&ev, '\0', sizeof(struct lttng_event));
@@ -897,29 +1219,41 @@ void *setup_live_tracing()
 	if ((ret = lttng_enable_event(handle, &ev, channel_name)) < 0) {
 		fprintf(stderr,"error enabling event : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error_session;
 	}
 
+	memset(&ev, '\0', sizeof(struct lttng_event));
 	ev.type = LTTNG_EVENT_SYSCALL;
 	if ((ret = lttng_enable_event(handle, &ev, channel_name)) < 0) {
 		fprintf(stderr,"error enabling syscalls : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error_session;
+	}
+
+	ret = enable_kprobes(handle, channel_name);
+	if (ret < 0) {
+		goto error_session;
 	}
 
 	kctxpid.ctx = LTTNG_EVENT_CONTEXT_PID;
 	lttng_add_context(handle, &kctxpid, NULL, NULL);
+	kctxtid.ctx = LTTNG_EVENT_CONTEXT_TID;
+	lttng_add_context(handle, &kctxtid, NULL, NULL);
 	kctxppid.ctx = LTTNG_EVENT_CONTEXT_PPID;
 	lttng_add_context(handle, &kctxppid, NULL, NULL);
 	kctxcomm.ctx = LTTNG_EVENT_CONTEXT_PROCNAME;
 	lttng_add_context(handle, &kctxcomm, NULL, NULL);
-	kctxtid.ctx = LTTNG_EVENT_CONTEXT_TID;
+	kctxpid.ctx = LTTNG_EVENT_CONTEXT_VPID;
+	lttng_add_context(handle, &kctxpid, NULL, NULL);
+	kctxtid.ctx = LTTNG_EVENT_CONTEXT_VTID;
+	lttng_add_context(handle, &kctxtid, NULL, NULL);
+	kctxtid.ctx = LTTNG_EVENT_CONTEXT_HOSTNAME;
 	lttng_add_context(handle, &kctxtid, NULL, NULL);
 
 	if ((ret = lttng_start_tracing("test")) < 0) {
 		fprintf(stderr,"error starting tracing : %s\n",
 				helper_lttcomm_get_readable_code(ret));
-		goto end;
+		goto error_session;
 	}
 
 	helper_kernctl_buffer_flush(consumerd_metadata);
@@ -927,14 +1261,20 @@ void *setup_live_tracing()
 	/* block until metadata is ready */
 	sem_init(&metadata_available, 0, 0);
 
-end:
-	return NULL;
+	return 0;
+
+error_session:
+	lttng_destroy_session("test");
+error:
+	return -1;
 }
 
 int main(int argc, char **argv)
 {
 	int ret;
 	struct bt_context *bt_ctx = NULL;
+	struct mmap_stream *mmap_info;
+	unsigned long mmap_len;
 
 	ret = parse_options(argc, argv);
 	if (ret < 0) {
@@ -946,15 +1286,50 @@ int main(int argc, char **argv)
 	}
 
 	if (!opt_input_path) {
-		setup_live_tracing();
+		if (opt_textdump) {
+			signal(SIGTERM, handle_textdump_sigterm);
+			signal(SIGINT, handle_textdump_sigterm);
+		}
 		init_lttngtop();
+		ret = setup_live_tracing();
+		if (ret < 0) {
+			goto end;
+		}
 		if (!opt_textdump) {
 			pthread_create(&display_thread, NULL, ncurses_display, (void *) NULL);
 			pthread_create(&timer_thread, NULL, refresh_thread, (void *) NULL);
 		}
-		live_consume();
+		while (!quit) {
+			reload_trace = 0;
+			live_consume(&bt_ctx);
+			iter_trace(bt_ctx);
+			ret = bt_context_remove_trace(bt_ctx, 0);
+			if (ret != 0)
+				fprintf(stderr, "error removing trace\n");
+			if (bt_ctx) {
+				bt_context_put(bt_ctx);
+			}
+
+			/*
+			 * since we receive all FDs every time there is an
+			 * update and the FD number is different every time,
+			 * we don't know which one are valid.
+			 * so we check if all FDs are usable with a simple
+			 * ioctl call.
+			 */
+			bt_list_for_each_entry(mmap_info, &mmap_list.head, list) {
+				ret = helper_kernctl_get_mmap_len(mmap_info->fd, &mmap_len);
+				if (ret != 0) {
+					bt_list_del(&mmap_info->list);
+				}
+			}
+			sem_post(&metadata_available);
+		}
+
+		pthread_join(timer_thread, NULL);
+		quit = 1;
+		pthread_join(display_thread, NULL);
 
-		sleep(2000);
 		lttng_stop_tracing("test");
 		lttng_destroy_session("test");
 
@@ -979,8 +1354,8 @@ int main(int argc, char **argv)
 
 		iter_trace(bt_ctx);
 
-		quit = 1;
 		pthread_join(display_thread, NULL);
+		quit = 1;
 		pthread_join(timer_thread, NULL);
 	}