--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#ifndef CEPH_TRACEPOINT_PROVIDER_H
+#define CEPH_TRACEPOINT_PROVIDER_H
+
+#include "common/config_obs.h"
+#include "common/Mutex.h"
+#include <dlfcn.h>
+
+struct md_config_t;
+
+class TracepointProvider : public md_config_obs_t, boost::noncopyable {
+public:
+ struct Traits {
+ const char *library;
+ const char *config_key;
+
+ Traits(const char *library, const char *config_key)
+ : library(library), config_key(config_key) {
+ }
+ };
+
+ class Singleton {
+ public:
+ Singleton(CephContext *cct, const char *library, const char *config_key)
+ : tracepoint_provider(new TracepointProvider(cct, library, config_key)) {
+ }
+ ~Singleton() {
+ delete tracepoint_provider;
+ }
+
+ inline bool is_enabled() const {
+ return tracepoint_provider->m_handle != nullptr;
+ }
+ private:
+ TracepointProvider *tracepoint_provider;
+ };
+
+ template <const Traits &traits>
+ class TypedSingleton : public Singleton {
+ public:
+ explicit TypedSingleton(CephContext *cct)
+ : Singleton(cct, traits.library, traits.config_key) {
+ }
+ };
+
+ TracepointProvider(CephContext *cct, const char *library,
+ const char *config_key);
+ ~TracepointProvider() override;
+
+ template <const Traits &traits>
+ static void initialize(CephContext *cct) {
+#ifdef WITH_LTTNG
+ TypedSingleton<traits> *singleton;
+ cct->lookup_or_create_singleton_object(singleton, traits.library);
+#endif
+ }
+
+protected:
+ const char** get_tracked_conf_keys() const override {
+ return m_config_keys;
+ }
+ void handle_conf_change(const struct md_config_t *conf,
+ const std::set <std::string> &changed) override;
+
+private:
+ CephContext *m_cct;
+ std::string m_library;
+ mutable const char* m_config_keys[2];
+
+ Mutex m_lock;
+ void* m_handle = nullptr;
+
+ void verify_config(const struct md_config_t *conf);
+};
+
+#endif // CEPH_TRACEPOINT_PROVIDER_H