X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=ltt-events.c;h=3532dee5a1c8d46e246fa14c8e6c07a1257f26c7;hb=da4e23320ee3bed6a19fe29c8a0b8b78387be7f3;hp=a94e8f9a1dde6a6e315133e59c66e3659455f99d;hpb=e64957da15e3652322dcf6a5389beb01901de8e6;p=lttng-modules.git

diff --git a/ltt-events.c b/ltt-events.c
index a94e8f9a..3532dee5 100644
--- a/ltt-events.c
+++ b/ltt-events.c
@@ -14,7 +14,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/jiffies.h>
-#include <linux/uuid.h>
+#include "wrapper/uuid.h"
 #include "wrapper/vmalloc.h"	/* for wrapper_vmalloc_sync_all() */
 #include "ltt-events.h"
 #include "ltt-tracer.h"
@@ -34,8 +34,6 @@ int _ltt_event_metadata_statedump(struct ltt_session *session,
 static
 int _ltt_session_metadata_statedump(struct ltt_session *session);
 
-
-static
 void synchronize_trace(void)
 {
 	synchronize_sched();
@@ -108,12 +106,9 @@ int ltt_session_enable(struct ltt_session *session)
 
 	ACCESS_ONCE(session->active) = 1;
 	ACCESS_ONCE(session->been_active) = 1;
-	synchronize_trace();	/* Wait for in-flight events to complete */
 	ret = _ltt_session_metadata_statedump(session);
-	if (ret) {
+	if (ret)
 		ACCESS_ONCE(session->active) = 0;
-		synchronize_trace();	/* Wait for in-flight events to complete */
-	}
 end:
 	mutex_unlock(&sessions_mutex);
 	return ret;
@@ -129,7 +124,6 @@ int ltt_session_disable(struct ltt_session *session)
 		goto end;
 	}
 	ACCESS_ONCE(session->active) = 0;
-	synchronize_trace();	/* Wait for in-flight events to complete */
 end:
 	mutex_unlock(&sessions_mutex);
 	return ret;
@@ -139,6 +133,8 @@ int ltt_channel_enable(struct ltt_channel *channel)
 {
 	int old;
 
+	if (channel == channel->session->metadata)
+		return -EPERM;
 	old = xchg(&channel->enabled, 1);
 	if (old)
 		return -EEXIST;
@@ -149,6 +145,8 @@ int ltt_channel_disable(struct ltt_channel *channel)
 {
 	int old;
 
+	if (channel == channel->session->metadata)
+		return -EPERM;
 	old = xchg(&channel->enabled, 0);
 	if (!old)
 		return -EEXIST;
@@ -159,6 +157,8 @@ int ltt_event_enable(struct ltt_event *event)
 {
 	int old;
 
+	if (event->chan == event->chan->session->metadata)
+		return -EPERM;
 	old = xchg(&event->enabled, 1);
 	if (old)
 		return -EEXIST;
@@ -169,6 +169,8 @@ int ltt_event_disable(struct ltt_event *event)
 {
 	int old;
 
+	if (event->chan == event->chan->session->metadata)
+		return -EPERM;
 	old = xchg(&event->enabled, 0);
 	if (!old)
 		return -EEXIST;
@@ -194,7 +196,7 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 				       unsigned int read_timer_interval)
 {
 	struct ltt_channel *chan;
-	struct ltt_transport *transport;
+	struct ltt_transport *transport = NULL;
 
 	mutex_lock(&sessions_mutex);
 	if (session->been_active)
@@ -205,6 +207,10 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 		       transport_name);
 		goto notransport;
 	}
+	if (!try_module_get(transport->owner)) {
+		printk(KERN_WARNING "LTT : Can't lock transport module.\n");
+		goto notransport;
+	}
 	chan = kzalloc(sizeof(struct ltt_channel), GFP_KERNEL);
 	if (!chan)
 		goto nomem;
@@ -222,6 +228,7 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 		goto create_error;
 	chan->enabled = 1;
 	chan->ops = &transport->ops;
+	chan->transport = transport;
 	list_add(&chan->list, &session->chan);
 	mutex_unlock(&sessions_mutex);
 	return chan;
@@ -229,6 +236,8 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 create_error:
 	kfree(chan);
 nomem:
+	if (transport)
+		module_put(transport->owner);
 notransport:
 active:
 	mutex_unlock(&sessions_mutex);
@@ -242,6 +251,7 @@ static
 void _ltt_channel_destroy(struct ltt_channel *chan)
 {
 	chan->ops->channel_destroy(chan->chan);
+	module_put(chan->transport->owner);
 	list_del(&chan->list);
 	lttng_destroy_context(chan->ctx);
 	kfree(chan);