* TRACE_EVENT_FN to perform any (un)registration work.
*/
+struct trace_event {
+ const char *name;
+ int (*regfunc)(void *data);
+ int (*unregfunc)(void *data);
+} __attribute__((aligned(32)));
+
+struct trace_event_lib {
+ struct trace_event *trace_events_start;
+ int trace_events_count;
+ struct list_head list;
+};
+
+struct trace_event_iter {
+ struct trace_event_lib *lib;
+ struct trace_event *trace_event;
+};
+
+extern void lock_trace_events(void);
+extern void unlock_trace_events(void);
+
+extern void trace_event_iter_start(struct trace_event_iter *iter);
+extern void trace_event_iter_next(struct trace_event_iter *iter);
+extern void trace_event_iter_reset(struct trace_event_iter *iter);
+
+extern int trace_event_get_iter_range(struct trace_event **trace_event,
+ struct trace_event *begin,
+ struct trace_event *end);
+
+extern void trace_event_update_process(void);
+extern int is_trace_event_enabled(const char *channel, const char *name);
+
+extern int trace_event_register_lib(struct trace_event *start_trace_events,
+ int trace_event_count);
+
+extern int trace_event_unregister_lib(struct trace_event *start_trace_events);
+
+#define TRACE_EVENT_LIB \
+ extern struct trace_event __start___trace_events[] \
+ __attribute__((weak, visibility("hidden"))); \
+ extern struct trace_event __stop___trace_events[] \
+ __attribute__((weak, visibility("hidden"))); \
+ static void __attribute__((constructor)) \
+ __trace_events__init(void) \
+ { \
+ long trace_event_count =((long)__stop___trace_events- \
+ (long)__start___trace_events) \
+ /sizeof(struct trace_event); \
+ trace_event_register_lib(__start___trace_events, \
+ trace_event_count); \
+ } \
+ \
+ static void __attribute__((destructor)) \
+ __trace_event__destroy(void) \
+ { \
+ trace_event_unregister_lib(__start___trace_events); \
+ }
+
#define DECLARE_TRACE_EVENT_CLASS(name, proto, args, tstruct, assign, print)
#define DEFINE_TRACE_EVENT(template, name, proto, args) \
DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
--- /dev/null
+/*
+ * 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;
+}
projects / ust.git / commitdiff
