From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 16 Nov 2011 00:15:18 +0000 (-0500)
Subject: lttng-sessiond: keep enabled/active state for sessions, cleanup enabled state for... 
X-Git-Tag: v2.0-pre15~109
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=464dd62d5617322366e321877b440951e00a0152;p=lttng-tools.git

lttng-sessiond: keep enabled/active state for sessions, cleanup enabled state for events/channels

allows

lttng list
Available tracing sessions:
  1) test1 (/root/lttng-traces/test1-20111115-191312) [inactive]
  2) test2 (/root/lttng-traces/test2-20111115-191310) [active]

and

root@thinkos:~# lttng list test2
Tracing session test2: [active]
    Trace path: /root/lttng-traces/test2-20111115-191502

When events/channels/sessions enabled state is set to -1, show an empty
string instead of the meaningless "[enabled: -1]".

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/include/lttng/lttng.h b/include/lttng/lttng.h
index ee749c1f6..280075037 100644
--- a/include/lttng/lttng.h
+++ b/include/lttng/lttng.h
@@ -189,6 +189,7 @@ struct lttng_session {
 	char name[NAME_MAX];
 	/* The path where traces are written */
 	char path[PATH_MAX];
+	uint32_t enabled;	/* enabled/started: 1, disabled/stopped: 0 */
 };
 
 /*
diff --git a/lttng-sessiond/main.c b/lttng-sessiond/main.c
index d1cc3fa8f..2e6292d38 100644
--- a/lttng-sessiond/main.c
+++ b/lttng-sessiond/main.c
@@ -1790,6 +1790,7 @@ static void list_lttng_sessions(struct lttng_session *sessions)
 		sessions[i].path[PATH_MAX - 1] = '\0';
 		strncpy(sessions[i].name, session->name, NAME_MAX);
 		sessions[i].name[NAME_MAX - 1] = '\0';
+		sessions[i].enabled = session->enabled;
 		i++;
 	}
 }
@@ -2512,6 +2513,10 @@ static int cmd_start_trace(struct ltt_session *session)
 	ksession = session->kernel_session;
 	usess = session->ust_session;
 
+	if (session->enabled)
+		return LTTCOMM_UST_START_FAIL;
+	session->enabled = 1;
+
 	/* Kernel tracing */
 	if (ksession != NULL) {
 		struct ltt_kernel_channel *kchan;
@@ -2597,6 +2602,10 @@ static int cmd_stop_trace(struct ltt_session *session)
 	/* Short cut */
 	ksession = session->kernel_session;
 
+	if (!session->enabled)
+		return LTTCOMM_UST_START_FAIL;
+	session->enabled = 0;
+
 	/* Kernel tracer */
 	if (ksession != NULL) {
 		DBG("Stop kernel tracing");
diff --git a/lttng-sessiond/session.h b/lttng-sessiond/session.h
index f6a9fff4d..2d077a4bc 100644
--- a/lttng-sessiond/session.h
+++ b/lttng-sessiond/session.h
@@ -67,6 +67,7 @@ struct ltt_session {
 	 */
 	pthread_mutex_t lock;
 	struct cds_list_head list;
+	int enabled;	/* enabled/started flag */
 };
 
 /* Prototypes */
diff --git a/lttng/commands/list.c b/lttng/commands/list.c
index fcfaa3f23..a3d8868b5 100644
--- a/lttng/commands/list.c
+++ b/lttng/commands/list.c
@@ -109,6 +109,28 @@ end:
 	return cmdline;
 }
 
+static
+const char *active_string(int value)
+{
+	switch (value) {
+	case 0:	return " [active]";
+	case 1: return " [inactive]";
+	case -1: return "";
+	default: return NULL;
+	}
+}
+
+static
+const char *enabled_string(int value)
+{
+	switch (value) {
+	case 0:	return " [enabled]";
+	case 1: return " [disabled]";
+	case -1: return "";
+	default: return NULL;
+	}
+}
+
 /*
  * Pretty print single event.
  */
@@ -116,12 +138,12 @@ static void print_events(struct lttng_event *event)
 {
 	switch (event->type) {
 	case LTTNG_EVENT_TRACEPOINT:
-		MSG("%s%s (type: tracepoint) [enabled: %d]", indent6,
-				event->name, event->enabled);
+		MSG("%s%s (type: tracepoint)%s", indent6,
+				event->name, enabled_string(event->enabled));
 		break;
 	case LTTNG_EVENT_PROBE:
-		MSG("%s%s (type: probe) [enabled: %d]", indent6,
-				event->name, event->enabled);
+		MSG("%s%s (type: probe)%s", indent6,
+				event->name, enabled_string(event->enabled));
 		if (event->attr.probe.addr != 0) {
 			MSG("%saddr: 0x%" PRIx64, indent8, event->attr.probe.addr);
 		} else {
@@ -131,17 +153,17 @@ static void print_events(struct lttng_event *event)
 		break;
 	case LTTNG_EVENT_FUNCTION:
 	case LTTNG_EVENT_FUNCTION_ENTRY:
-		MSG("%s%s (type: function) [enabled: %d]", indent6,
-				event->name, event->enabled);
+		MSG("%s%s (type: function)%s", indent6,
+				event->name, enabled_string(event->enabled));
 		MSG("%ssymbol: \"%s\"", indent8, event->attr.ftrace.symbol_name);
 		break;
 	case LTTNG_EVENT_SYSCALL:
-		MSG("%s (type: syscall) [enabled: %d]", indent6,
-				event->enabled);
+		MSG("%s (type: syscall)%s", indent6,
+				enabled_string(event->enabled));
 		break;
 	case LTTNG_EVENT_NOOP:
-		MSG("%s (type: noop) [enabled: %d]", indent6,
-				event->enabled);
+		MSG("%s (type: noop)%s", indent6,
+				enabled_string(event->enabled));
 		break;
 	case LTTNG_EVENT_ALL:
 		/* We should never have "all" events in list. */
@@ -282,7 +304,7 @@ error:
  */
 static void print_channel(struct lttng_channel *channel)
 {
-	MSG("- %s (enabled: %d):\n", channel->name, channel->enabled);
+	MSG("- %s:%s\n", channel->name, enabled_string(channel->enabled));
 
 	MSG("%sAttributes:", indent4);
 	MSG("%soverwrite mode: %d", indent6, channel->attr.overwrite);
@@ -385,14 +407,14 @@ static int list_sessions(const char *session_name)
 		if (session_name != NULL) {
 			if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 				session_found = 1;
-				MSG("Tracing session %s:", session_name);
+				MSG("Tracing session %s:%s", session_name, active_string(sessions[i].enabled));
 				MSG("%sTrace path: %s\n", indent4, sessions[i].path);
 				break;
 			}
 			continue;
 		}
 
-		MSG("  %d) %s (%s)", i + 1, sessions[i].name, sessions[i].path);
+		MSG("  %d) %s (%s)%s", i + 1, sessions[i].name, sessions[i].path, active_string(sessions[i].enabled));
 
 		if (session_found) {
 			break;