X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=libust%2Ftrace_event.c;fp=libust%2Ftrace_event.c;h=af1e3fb1180e55753a8adb63a2a84246f9280509;hb=0c0686eefbf60682c54bc4b3c0bc593250deedc1;hp=0000000000000000000000000000000000000000;hpb=1e620c5350cfbd0b0be4122547115dd4da503bcf;p=ust.git

diff --git a/libust/trace_event.c b/libust/trace_event.c
new file mode 100644
index 0000000..af1e3fb
--- /dev/null
+++ b/libust/trace_event.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2010 Nils Carlson
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ *
+ */
+
+#include <errno.h>
+#include <ust/tracepoint.h>
+#include <ust/core.h>
+#include <ust/kcompat/kcompat.h>
+#include "usterr.h"
+
+#define _LGPL_SOURCE
+#include <urcu-bp.h>
+
+/* libraries that contain trace_events (struct trace_event_lib) */
+static LIST_HEAD(libs);
+
+static DEFINE_MUTEX(trace_events_mutex);
+
+void lock_trace_events(void)
+{
+	pthread_mutex_lock(&trace_events_mutex);
+}
+
+void unlock_trace_events(void)
+{
+	pthread_mutex_unlock(&trace_events_mutex);
+}
+
+
+int lib_get_iter_trace_events(struct trace_event_iter *iter)
+{
+	struct trace_event_lib *iter_lib;
+	int found = 0;
+
+	list_for_each_entry(iter_lib, &libs, list) {
+		if (iter_lib < iter->lib)
+			continue;
+		else if (iter_lib > iter->lib)
+			iter->trace_event = NULL;
+		found = trace_event_get_iter_range(&iter->trace_event,
+			iter_lib->trace_events_start,
+			iter_lib->trace_events_start + iter_lib->trace_events_count);
+		if (found) {
+			iter->lib = iter_lib;
+			break;
+		}
+	}
+	return found;
+}
+
+/**
+ * trace_event_get_iter_range - Get a next trace_event iterator given a range.
+ * @trace_event: current trace_events (in), next trace_event (out)
+ * @begin: beginning of the range
+ * @end: end of the range
+ *
+ * Returns whether a next trace_event has been found (1) or not (0).
+ * Will return the first trace_event in the range if the input trace_event is NULL.
+ */
+int trace_event_get_iter_range(struct trace_event **trace_event, struct trace_event *begin,
+	struct trace_event *end)
+{
+	if (!*trace_event && begin != end) {
+		*trace_event = begin;
+		return 1;
+	}
+	if (*trace_event >= begin && *trace_event < end)
+		return 1;
+	return 0;
+}
+
+static void trace_event_get_iter(struct trace_event_iter *iter)
+{
+	int found = 0;
+
+	found = lib_get_iter_trace_events(iter);
+end:
+	if (!found)
+		trace_event_iter_reset(iter);
+}
+
+void trace_event_iter_start(struct trace_event_iter *iter)
+{
+	trace_event_get_iter(iter);
+}
+
+void trace_event_iter_next(struct trace_event_iter *iter)
+{
+	iter->trace_event++;
+	/*
+	 * iter->trace_event may be invalid because we blindly incremented it.
+	 * Make sure it is valid by marshalling on the trace_events, getting the
+	 * trace_events from following modules if necessary.
+	 */
+	trace_event_get_iter(iter);
+}
+
+void trace_event_iter_reset(struct trace_event_iter *iter)
+{
+	iter->lib = NULL;
+	iter->trace_event = NULL;
+}
+
+int trace_event_register_lib(struct trace_event *trace_events_start,
+			     int trace_events_count)
+{
+	struct trace_event_lib *pl;
+
+	pl = (struct trace_event_lib *) malloc(sizeof(struct trace_event_lib));
+
+	pl->trace_events_start = trace_events_start;
+	pl->trace_events_count = trace_events_count;
+
+	/* FIXME: maybe protect this with its own mutex? */
+	pthread_mutex_lock(&trace_events_mutex);
+	list_add(&pl->list, &libs);
+	pthread_mutex_unlock(&trace_events_mutex);
+
+	DBG("just registered a trace_events section from %p and having %d trace_events", trace_events_start, trace_events_count);
+
+	return 0;
+}
+
+int trace_event_unregister_lib(struct trace_event *trace_events_start)
+{
+	struct trace_event_lib *lib;
+
+	pthread_mutex_lock(&trace_events_mutex);
+
+	list_for_each_entry(lib, &libs, list) {
+		if(lib->trace_events_start == trace_events_start) {
+			struct trace_event_lib *lib2free = lib;
+			list_del(&lib->list);
+			free(lib2free);
+			break;
+		}
+	}
+
+	pthread_mutex_unlock(&trace_events_mutex);
+
+	return 0;
+}