Move implementation for DSPLoadCalculator back into header

It can be inline now that it is much simpler

1 files changed, 29 insertions, 4 deletions

diff --git a/libs/ardour/ardour/dsp_load_calculator.h b/libs/ardour/ardour/dsp_load_calculator.h
index 42386e2cb0..1da9786d36 100644
--- a/libs/ardour/ardour/dsp_load_calculator.h
+++ b/libs/ardour/ardour/dsp_load_calculator.h
@@ -23,11 +23,9 @@
 #include <cassert>
 #include <algorithm>
 
-#include "ardour/libardour_visibility.h"
-
 namespace ARDOUR {
 
-class LIBARDOUR_API DSPLoadCalculator {
+class DSPLoadCalculator {
 public:
 	DSPLoadCalculator()
 	    : m_max_time_us(0)
@@ -50,7 +48,34 @@ public:
 		m_start_timestamp_us = start_timestamp_us;
 	}
 
-	void set_stop_timestamp_us(int64_t stop_timestamp_us);
+	void set_stop_timestamp_us(int64_t stop_timestamp_us)
+	{
+		m_stop_timestamp_us = stop_timestamp_us;
+
+		/* querying the performance counter can fail occasionally (-1).
+		 * Also on some multi-core systems, timers are CPU specific and not
+		 * synchronized. We assume they differ more than a few milliseconds
+		 * (4 * nominal cycle time) and simply ignore cases where the
+		 * execution switches cores.
+		 */
+		if (m_start_timestamp_us < 0 || m_stop_timestamp_us < 0 ||
+		    m_start_timestamp_us > m_stop_timestamp_us ||
+		    elapsed_time_us() > max_timer_error()) {
+			return;
+		}
+
+		if (elapsed_time_us() > m_max_time_us) {
+			m_dsp_load = 1.0f;
+		} else {
+			const float load = elapsed_time_us() / (float)m_max_time_us;
+			if (load > m_dsp_load) {
+				m_dsp_load = load;
+			} else {
+				const float alpha = 0.2f * (m_max_time_us * 1e-6f);
+				m_dsp_load = m_dsp_load + alpha * (load - m_dsp_load) + 1e-12;
+			}
+		}
+	}
 
 	int64_t elapsed_time_us()
 	{