X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=ltt-events.c;h=f22351fcb0f92fc83070f3a0b90009ee3adba7ab;hb=ad1c05e136eba463795ba592e5f6c27542643e16;hp=688d7f3bb491811e131cf846e14d251706f80dfa;hpb=e5382b6d90ebe0752f5955a91525f3207f440e18;p=lttng-modules.git

diff --git a/ltt-events.c b/ltt-events.c
index 688d7f3b..f22351fc 100644
--- a/ltt-events.c
+++ b/ltt-events.c
@@ -13,18 +13,22 @@ static LIST_HEAD(sessions);
 static DEFINE_MUTEX(sessions_mutex);
 static struct kmem_cache *event_cache;
 
-struct ltt_session *ltt_session_create(char *name)
+static void synchronize_trace(void)
+{
+	synchronize_sched();
+#ifdef CONFIG_PREEMPT_RT
+	synchronize_rcu();
+#endif
+}
+
+struct ltt_session *ltt_session_create(void)
 {
 	struct ltt_session *session;
 
 	mutex_lock(&sessions_mutex);
-	list_for_each_entry(session, &sessions, list)
-		if (!strcmp(session->name, name))
-			goto exist;
-	session = kmalloc(sizeof(struct ltt_session) + strlen(name) + 1);
+	session = kmalloc(sizeof(struct ltt_session));
 	if (!session)
 		return NULL;
-	strcpy(session->name, name);
 	INIT_LIST_HEAD(&session->chan);
 	list_add(&session->list, &sessions);
 	mutex_unlock(&sessions_mutex);
@@ -41,6 +45,8 @@ int ltt_session_destroy(struct ltt_session *session)
 	struct ltt_event *event, *tmpevent;
 
 	mutex_lock(&sessions_mutex);
+	session->active = 0;
+	synchronize_trace();	/* Wait for in-flight events to complete */
 	list_for_each_entry_safe(event, tmpevent, &session->events, list)
 		_ltt_event_destroy(event);
 	list_for_each_entry_safe(chan, tmpchan, &session->chan, list)
@@ -50,7 +56,7 @@ int ltt_session_destroy(struct ltt_session *session)
 	kfree(session);
 }
 
-struct ltt_channel *ltt_channel_create(struct ltt_session *session, char *name,
+struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 				       int overwrite, void *buf_addr,
 				       size_t subbuf_size, size_t num_subbuf,
 				       unsigned int switch_timer_interval,
@@ -61,13 +67,9 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session, char *name,
 	mutex_lock(&sessions_mutex);
 	if (session->active)
 		goto active;	/* Refuse to add channel to active session */
-	list_for_each_entry(chan, &session->chan, list)
-		if (!strcmp(chan->name, name))
-			goto exist;
-	chan = kmalloc(sizeof(struct ltt_channel) + strlen(name) + 1, GFP_KERNEL);
+	chan = kmalloc(sizeof(struct ltt_channel), GFP_KERNEL);
 	if (!chan)
 		return NULL;
-	strcpy(chan->name, name);
 	chan->session = session;
 
 	/* TODO: create rb channel */
@@ -86,6 +88,7 @@ active:
  */
 int _ltt_channel_destroy(struct ltt_channel *chan)
 {
+	/* TODO: destroy rb channel */
 	list_del(&chan->list);
 	kfree(chan);
 }
@@ -94,9 +97,11 @@ int _ltt_channel_destroy(struct ltt_channel *chan)
  * Supports event creation while tracing session is active.
  */
 struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
-				   void *filter)
+				   enum instrum_type itype,
+				   void *probe, void *filter)
 {
 	struct ltt_event *event;
+	int ret;
 
 	mutex_lock(&sessions_mutex);
 	if (chan->free_event_id == -1UL)
@@ -116,12 +121,20 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
 		goto error;
 	strcpy(event->name, name);
 	event->chan = chan;
+	event->probe = probe;
 	event->filter = filter;
 	event->id = chan->free_event_id++;
+	event->itype = itype;
 	mutex_unlock(&sessions_mutex);
 	/* Populate ltt_event structure before tracepoint registration. */
 	smp_wmb();
-	/* TODO register to tracepoint */
+	switch (itype) {
+	case INSTRUM_TRACEPOINTS:
+		ret = tracepoint_probe_register(name, probe, event);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+	}
 	return event;
 
 error:
@@ -138,7 +151,13 @@ full:
  */
 int _ltt_event_destroy(struct ltt_event *event)
 {
-	/* TODO unregister from tracepoint */
+	switch (event->itype) {
+	case INSTRUM_TRACEPOINTS:
+		ret = tracepoint_probe_unregister(name, event->probe, event);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+	}
 	kfree(event->name);
 	kmem_cache_free(event);
 }
@@ -150,10 +169,23 @@ static int __init ltt_events_init(void)
 	events_cache = KMEM_CACHE(ltt_event, 0);
 	if (!events_cache)
 		return -ENOMEM;
+
+	/* TODO: show ABI to userspace */
+
 	return 0;
 }
 
 static void __exit ltt_events_exit(void)
 {
+	struct ltt_session *session, *tmpsession;
+
+	/* TODO: hide ABI from userspace, wait for callers to release refs. */
+
+	list_for_each_entry_safe(session, tmpsession, &sessions, list)
+		ltt_session_destroy(session);
 	kmem_cache_destroy(events_cache);
 }
+
+MODULE_LICENSE("GPL and additional rights");
+MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
+MODULE_DESCRIPTION("LTTng Events");