add some initial timing points for dsp stats

libs/ardour/ardour/audio_backend.h

@@ -849,6 +849,17 @@ public:
 		return false;
 	}
 
+	enum TimingTypes {
+		DeviceWait = 0,
+		PreProcess = 1,
+		ProcessCallback = 2,
+		PostProcess = 3,
+		/* end */
+		NTT = 4
+	};
+
+	PBD::TimingStats dsp_stats[NTT];
+
 protected:
 	AudioBackendInfo& _info;
 	AudioEngine&      engine;

libs/ardour/ardour/audioengine.h

@@ -250,6 +250,14 @@ class LIBARDOUR_API AudioEngine : public PortManager, public SessionHandlePtr
 	void add_pending_port_deletion (Port*);
 	void queue_latency_update (bool);
 
+	enum TimingTypes {
+		ProcessCallback = 0,
+		/* end */
+		NTT = 1
+	};
+
+	PBD::TimingStats dsp_stats[NTT];
+
   private:
 	AudioEngine ();
 

libs/ardour/ardour/session.h

@@ -1322,6 +1322,17 @@ public:
 	std::vector<struct ptflookup> ptfwavpair;
 	SourceList pt_imported_sources;
 
+	enum TimingTypes {
+		OverallProcess = 0,
+		ProcessFunction = 1,
+		NoRoll = 2,
+		Roll = 3,
+		/* end */
+		NTT = 4
+	};
+
+	PBD::TimingStats dsp_stats[NTT];
+
 protected:
 	friend class AudioEngine;
 	void set_block_size (pframes_t nframes);

libs/ardour/audioengine.cc

@@ -228,6 +228,7 @@ __attribute__((annotate("realtime")))
 int
 AudioEngine::process_callback (pframes_t nframes)
 {
+	TimerRAII tr (dsp_stats[ProcessCallback]);
 	Glib::Threads::Mutex::Lock tm (_process_lock, Glib::Threads::TRY_LOCK);
 	Port::set_speed_ratio (1.0);
 

libs/ardour/session_process.cc

@@ -74,6 +74,8 @@ using namespace std;
 void
 Session::process (pframes_t nframes)
 {
+	TimerRAII tr (dsp_stats[OverallProcess]);
+
 	samplepos_t transport_at_start = _transport_sample;
 
 	_silent = false;
@@ -166,6 +168,7 @@ int
 Session::no_roll (pframes_t nframes)
 {
 	PT_TIMING_CHECK (4);
+	TimerRAII tr (dsp_stats[NoRoll]);
 
 	samplepos_t end_sample = _transport_sample + floor (nframes * _transport_fsm->transport_speed());
 	int ret = 0;
@@ -212,6 +215,7 @@ Session::no_roll (pframes_t nframes)
 int
 Session::process_routes (pframes_t nframes, bool& need_butler)
 {
+	TimerRAII tr (dsp_stats[Roll]);
 	boost::shared_ptr<RouteList> r = routes.reader ();
 
 	const samplepos_t start_sample = _transport_sample;
@@ -331,6 +335,7 @@ void
 Session::process_with_events (pframes_t nframes)
 {
 	PT_TIMING_CHECK (3);
+	TimerRAII tr (dsp_stats[ProcessFunction]);
 
 	SessionEvent*  ev;
 	pframes_t      this_nframes;
@@ -631,6 +636,7 @@ Session::transport_locked () const
 void
 Session::process_without_events (pframes_t nframes)
 {
+	TimerRAII tr (dsp_stats[ProcessFunction]);
 	bool session_needs_butler = false;
 	samplecnt_t samples_moved;
 

libs/backends/alsa/alsa_audiobackend.cc

@@ -1852,9 +1852,12 @@ AlsaAudioBackend::main_process_thread ()
 		}
 
 		if (!_freewheel) {
+			dsp_stats[DeviceWait].start();
 			nr = _pcmi->pcm_wait ();
+			dsp_stats[DeviceWait].update();
 
 			/* update DLL */
+			dsp_stats[PreProcess].start();
 			uint64_t clock0 = g_get_monotonic_time ();
 			if (reset_dll || last_n_periods != 1) {
 				reset_dll    = false;
@@ -1957,11 +1960,13 @@ AlsaAudioBackend::main_process_thread ()
 
 				/* call engine process callback */
 				_last_process_start = g_get_monotonic_time ();
+				dsp_stats[PreProcess].update();
 				if (engine.process_callback (_samples_per_period)) {
 					_pcmi->pcm_stop ();
 					_active = false;
 					return 0;
 				}
+				dsp_stats[PostProcess].start ();
 
 				/* only used when adding/removing MIDI device/system ports */
 				pthread_mutex_lock (&_device_port_mutex);
@@ -2012,6 +2017,8 @@ AlsaAudioBackend::main_process_thread ()
 				_dsp_load_calc.set_stop_timestamp_us (g_get_monotonic_time ());
 				_dsp_load = _dsp_load_calc.get_dsp_load ();
 				++last_n_periods;
+
+				dsp_stats[PostProcess].update ();
 			}
 
 			if (xrun && (_pcmi->capt_xrun () > 0 || _pcmi->play_xrun () > 0)) {