From: David Goulet <david.goulet@polymtl.ca>
Date: Wed, 23 Nov 2011 18:19:04 +0000 (-0500)
Subject: Add UST default channel creation support
X-Git-Tag: v2.0-pre15~82
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=aea829b3086fb53d411eb79a5abe0e706d4d9cf3;p=lttng-tools.git

Add UST default channel creation support

When enabling event without a channel specified, a default channel
(channel0) will be created.

Also fix the enabled flag for channels when listing them.

Minor fix of code and comments.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>
---

diff --git a/lttng-sessiond/main.c b/lttng-sessiond/main.c
index dc71e0eae..bca057543 100644
--- a/lttng-sessiond/main.c
+++ b/lttng-sessiond/main.c
@@ -1922,6 +1922,7 @@ static void list_lttng_channels(int domain, struct ltt_session *session,
 			channels[i].attr.read_timer_interval =
 				uchan->attr.read_timer_interval;
 			channels[i].attr.output = uchan->attr.output;
+			channels[i].enabled = uchan->enabled;
 			i++;
 		}
 		break;
@@ -2134,14 +2135,14 @@ error:
  * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
  */
 static int cmd_enable_channel(struct ltt_session *session,
-		struct lttng_domain *domain, struct lttng_channel *attr)
+		int domain, struct lttng_channel *attr)
 {
 	int ret;
 	struct ltt_ust_session *usess = session->ust_session;
 
 	DBG("Enabling channel %s for session %s", attr->name, session->name);
 
-	switch (domain->type) {
+	switch (domain) {
 	case LTTNG_DOMAIN_KERNEL:
 	{
 		struct ltt_kernel_channel *kchan;
@@ -2432,13 +2433,34 @@ static int cmd_enable_event(struct ltt_session *session, int domain,
 	{
 		struct ltt_ust_channel *uchan;
 		struct ltt_ust_event *uevent;
+		struct lttng_channel *attr;
 
 		uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
 				channel_name);
 		if (uchan == NULL) {
-			/* TODO: Create default channel */
-			ret = LTTCOMM_UST_CHAN_NOT_FOUND;
-			goto error;
+			/* Create default channel */
+			attr = channel_new_default_attr(domain);
+			if (attr == NULL) {
+				ret = LTTCOMM_FATAL;
+				goto error;
+			}
+
+			/* Use the internal command enable channel */
+			ret = cmd_enable_channel(session, domain, attr);
+			if (ret < 0) {
+				goto error;
+			}
+
+			free(attr);
+
+			/* Get the newly created channel reference back */
+			uchan = trace_ust_find_channel_by_name(
+					usess->domain_global.channels, channel_name);
+			if (uchan == NULL) {
+				/* Something is really wrong */
+				ret = LTTCOMM_FATAL;
+				goto error;
+			}
 		}
 
 		uevent = trace_ust_find_event_by_name(uchan->events, event->name);
@@ -2720,7 +2742,6 @@ static int cmd_stop_trace(struct ltt_session *session)
 		kernel_wait_quiescent(kernel_tracer_fd);
 	}
 
-	/* Flag session that trace should start automatically */
 	if (usess) {
 		usess->start_trace = 0;
 
@@ -3159,7 +3180,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
 	}
 	case LTTNG_ENABLE_CHANNEL:
 	{
-		ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
+		ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
 				&cmd_ctx->lsm->u.channel.chan);
 		break;
 	}
diff --git a/lttng-sessiond/ust-app.c b/lttng-sessiond/ust-app.c
index 78c84bd75..cd5829cb6 100644
--- a/lttng-sessiond/ust-app.c
+++ b/lttng-sessiond/ust-app.c
@@ -1146,9 +1146,10 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		goto error_rcu_unlock;
 	}
 
-	/* upon restart, we skip the setup, already done */
-	if (ua_sess->started)
+	/* Upon restart, we skip the setup, already done */
+	if (ua_sess->started) {
 		goto skip_setup;
+	}
 
 	ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
 	if (ret < 0) {
@@ -1199,6 +1200,7 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
 		ret = -EINVAL;
 		goto error_rcu_unlock;
 	}
+
 	/* Setup UST consumer socket and send fds to it */
 	ret = ust_consumer_send_session(consumerd_fd, ua_sess);
 	if (ret < 0) {
diff --git a/lttng-sessiond/ust-app.h b/lttng-sessiond/ust-app.h
index ec6bafdfe..657ca4a12 100644
--- a/lttng-sessiond/ust-app.h
+++ b/lttng-sessiond/ust-app.h
@@ -96,7 +96,7 @@ struct ust_app_session {
 struct ust_app {
 	pid_t ppid;
 	uid_t uid;           /* User ID that owns the apps */
-	gid_t gid;           /* Group ID that owns the apps */	
+	gid_t gid;           /* Group ID that owns the apps */
 	int bits_per_long;
 	uint32_t v_major;    /* Verion major number */
 	uint32_t v_minor;    /* Verion minor number */