X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=libust%2Ftracer.c;h=ffcc2e74926996257ef7531fa622c1ee9179c0c9;hb=8d6300d3b3cb0219e1109e931a2219dbd812b24d;hp=ecf403adfeee3e6ea580fe8b3ad5f998de295c90;hpb=0222e1213f196b66cbc08cd29093aca4a28e9ffb;p=ust.git

diff --git a/libust/tracer.c b/libust/tracer.c
index ecf403a..ffcc2e7 100644
--- a/libust/tracer.c
+++ b/libust/tracer.c
@@ -182,7 +182,8 @@ static enum ltt_channels get_channel_type_from_name(const char *name)
 //ust// }
 
 static CDS_LIST_HEAD(ltt_transport_list);
-
+/* transport mutex, nests inside traces mutex (ltt_lock_traces) */
+static DEFINE_MUTEX(ltt_transport_mutex);
 /**
  * ltt_transport_register - LTT transport registration
  * @transport: transport structure
@@ -204,9 +205,9 @@ void ltt_transport_register(struct ltt_transport *transport)
 	 */
 //ust//	vmalloc_sync_all();
 
-	ltt_lock_traces();
+	pthread_mutex_lock(&ltt_transport_mutex);
 	cds_list_add_tail(&transport->node, &ltt_transport_list);
-	ltt_unlock_traces();
+	pthread_mutex_unlock(&ltt_transport_mutex);
 }
 
 /**
@@ -215,9 +216,9 @@ void ltt_transport_register(struct ltt_transport *transport)
  */
 void ltt_transport_unregister(struct ltt_transport *transport)
 {
-	ltt_lock_traces();
+	pthread_mutex_lock(&ltt_transport_mutex);
 	cds_list_del(&transport->node);
-	ltt_unlock_traces();
+	pthread_mutex_unlock(&ltt_transport_mutex);
 }
 
 static inline int is_channel_overwrite(enum ltt_channels chan,
@@ -324,7 +325,7 @@ struct ust_trace *_ltt_trace_find_setup(const char *trace_name)
  * ltt_release_transport - Release an LTT transport
  * @kref : reference count on the transport
  */
-void ltt_release_transport(struct kref *kref)
+void ltt_release_transport(struct urcu_ref *urcu_ref)
 {
 //ust// 	struct ust_trace *trace = container_of(kref,
 //ust// 			struct ust_trace, ltt_transport_kref);
@@ -335,10 +336,10 @@ void ltt_release_transport(struct kref *kref)
  * ltt_release_trace - Release a LTT trace
  * @kref : reference count on the trace
  */
-void ltt_release_trace(struct kref *kref)
+void ltt_release_trace(struct urcu_ref *urcu_ref)
 {
-	struct ust_trace *trace = _ust_container_of(kref,
-			struct ust_trace, kref);
+	struct ust_trace *trace = _ust_container_of(urcu_ref,
+			struct ust_trace, urcu_ref);
 	ltt_channels_trace_free(trace->channels);
 	free(trace);
 }
@@ -458,12 +459,15 @@ int ltt_trace_set_type(const char *trace_name, const char *trace_type)
 		goto traces_error;
 	}
 
+	pthread_mutex_lock(&ltt_transport_mutex);
 	cds_list_for_each_entry(tran_iter, &ltt_transport_list, node) {
 		if (!strcmp(tran_iter->name, trace_type)) {
 			transport = tran_iter;
 			break;
 		}
 	}
+	pthread_mutex_unlock(&ltt_transport_mutex);
+
 	if (!transport) {
 		ERR("Transport %s is not present", trace_type);
 		err = -EINVAL;
@@ -640,9 +644,9 @@ int ltt_trace_alloc(const char *trace_name)
 		goto traces_error;
 	}
 
-	kref_init(&trace->kref);
-	kref_init(&trace->ltt_transport_kref);
-//ust//	init_waitqueue_head(&trace->kref_wq);
+	urcu_ref_init(&trace->urcu_ref);
+	urcu_ref_init(&trace->ltt_transport_urcu_ref);
+//ust//	init_waitqueue_head(&trace->urcu_ref_wq);
 	trace->active = 0;
 //ust//	get_trace_clock();
 	trace->freq_scale = trace_clock_freq_scale();
@@ -795,9 +799,6 @@ static void __ltt_trace_destroy(struct ust_trace *trace, int drop)
 		}
 	}
 
-	return; /* FIXME: temporary for ust */
-//ust//	flush_scheduled_work();
-
 	/*
 	 * The currently destroyed trace is not in the trace list anymore,
 	 * so it's safe to call the async wakeup ourself. It will deliver
@@ -811,7 +812,7 @@ static void __ltt_trace_destroy(struct ust_trace *trace, int drop)
 			trace->ops->remove_channel(chan);
 	}
 
-	kref_put(&trace->ltt_transport_kref, ltt_release_transport);
+	urcu_ref_put(&trace->ltt_transport_urcu_ref, ltt_release_transport);
 
 //ust//	module_put(trace->transport->owner);
 
@@ -824,7 +825,7 @@ static void __ltt_trace_destroy(struct ust_trace *trace, int drop)
 //ust//		__wait_event_interruptible(trace->kref_wq,
 //ust//			(atomic_read(&trace->kref.refcount) == 1), ret);
 //ust//	}
-	kref_put(&trace->kref, ltt_release_trace);
+	urcu_ref_put(&trace->urcu_ref, ltt_release_trace);
 }
 
 int ltt_trace_destroy(const char *trace_name, int drop)
@@ -905,11 +906,11 @@ int ltt_trace_start(const char *trace_name)
 	ltt_unlock_traces();
 
 	/*
-	 * Call the kernel state dump.
-	 * Events will be mixed with real kernel events, it's ok.
+	 * Call the process-wide state dump.
 	 * Notice that there is no protection on the trace : that's exactly
 	 * why we iterate on the list and check for trace equality instead of
-	 * directly using this trace handle inside the logging function.
+	 * directly using this trace handle inside the logging function: we want
+	 * to record events only in a single trace in the trace session list.
 	 */
 
 	ltt_dump_marker_state(trace);