[gtk/tracing: 11/16] frame clock: Add tracing

[Matthias Clasen <matthiasc src gnome org>]

commit 1660bac6bda835e8ec5eb46ed28eff4de48abad2
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat May 19 20:24:21 2018 +0100

    frame clock: Add tracing
    
    Emit tracing data for frames. For now, we emit the
    entire frame, and the layout and paint phases. Also
    emit frames-per-second.

 gdk/gdkframeclockidle.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 105 insertions(+), 3 deletions(-)
---
diff --git a/gdk/gdkframeclockidle.c b/gdk/gdkframeclockidle.c
index 5a72624d76..ae6443a798 100644
--- a/gdk/gdkframeclockidle.c
+++ b/gdk/gdkframeclockidle.c
@@ -29,6 +29,7 @@
 #include "gdkinternals.h"
 #include "gdkframeclockprivate.h"
 #include "gdk.h"
+#include "gdkprofilerprivate.h"
 
 #ifdef G_OS_WIN32
 #include <windows.h>
@@ -113,6 +114,96 @@ get_sleep_serial (void)
   return sleep_serial;
 }
 
+static guint fps_counter = 0;
+
+static void
+add_timings_to_profiler (GdkFrameTimings *timings)
+{
+  gdk_profiler_add_mark (timings->frame_time * 1000,
+                         (timings->frame_end_time - timings->frame_time) * 1000,
+                         "frame", "");
+  if (timings->layout_start_time != 0)
+    gdk_profiler_add_mark (timings->layout_start_time * 1000,
+                           (timings->paint_start_time - timings->layout_start_time) * 1000,
+                            "layout", "");
+
+  if (timings->paint_start_time != 0)
+    gdk_profiler_add_mark (timings->paint_start_time * 1000,
+                           (timings->frame_end_time - timings->paint_start_time) * 1000,
+                            "paint", "");
+}
+
+static gint64
+guess_refresh_interval (GdkFrameClock *frame_clock)
+{
+  gint64 interval;
+  gint64 i;
+
+  interval = G_MAXINT64;
+
+  for (i = gdk_frame_clock_get_history_start (frame_clock);
+       i < gdk_frame_clock_get_frame_counter (frame_clock);
+       i++)
+    {
+      GdkFrameTimings *t, *before;
+      gint64 ts, before_ts;
+
+      t = gdk_frame_clock_get_timings (frame_clock, i);
+      before = gdk_frame_clock_get_timings (frame_clock, i - 1);
+      if (t == NULL || before == NULL)
+        continue;
+
+      ts = gdk_frame_timings_get_frame_time (t);
+      before_ts = gdk_frame_timings_get_frame_time (before);
+      if (ts == 0 || before_ts == 0)
+        continue;
+
+      interval = MIN (interval, ts - before_ts);
+    }
+
+  if (interval == G_MAXINT64)
+    return 0;
+
+  return interval;
+}
+
+static double
+frame_clock_get_fps (GdkFrameClock *frame_clock)
+{
+  GdkFrameTimings *start, *end;
+  gint64 start_counter, end_counter;
+  gint64 start_timestamp, end_timestamp;
+  gint64 interval;
+
+  start_counter = gdk_frame_clock_get_history_start (frame_clock);
+  end_counter = gdk_frame_clock_get_frame_counter (frame_clock);
+  start = gdk_frame_clock_get_timings (frame_clock, start_counter);
+  for (end = gdk_frame_clock_get_timings (frame_clock, end_counter);
+       end_counter > start_counter && end != NULL && !gdk_frame_timings_get_complete (end);
+       end = gdk_frame_clock_get_timings (frame_clock, end_counter))
+    end_counter--;
+  if (end_counter - start_counter < 4)
+    return 0.0;
+
+  start_timestamp = gdk_frame_timings_get_presentation_time (start);
+  end_timestamp = gdk_frame_timings_get_presentation_time (end);
+  if (start_timestamp == 0 || end_timestamp == 0)
+    {
+      start_timestamp = gdk_frame_timings_get_frame_time (start);
+      end_timestamp = gdk_frame_timings_get_frame_time (end);
+    }
+
+  interval = gdk_frame_timings_get_refresh_interval (end);
+  if (interval == 0)
+    {
+      interval = guess_refresh_interval (frame_clock);
+      if (interval == 0)
+        return 0.0;
+    }
+
+  return ((double) end_counter - start_counter) * G_USEC_PER_SEC / (end_timestamp - start_timestamp);
+}
+
 static void
 gdk_frame_clock_idle_init (GdkFrameClockIdle *frame_clock_idle)
 {
@@ -123,6 +214,11 @@ gdk_frame_clock_idle_init (GdkFrameClockIdle *frame_clock_idle)
 
   priv->frame_time = g_get_monotonic_time (); /* more sane than zero */
   priv->freeze_count = 0;
+
+#ifdef G_ENABLE_DEBUG
+  if (fps_counter == 0)
+    fps_counter = gdk_profiler_define_counter ("fps", "Frames per Second");
+#endif
 }
 
 static void
@@ -405,7 +501,7 @@ gdk_frame_clock_paint_idle (void *data)
             {
              int iter;
 #ifdef G_ENABLE_DEBUG
-              if (GDK_DEBUG_CHECK (FRAMES))
+              if (GDK_DEBUG_CHECK (FRAMES) || gdk_profiler_is_running ())
                 {
                   if (priv->phase != GDK_FRAME_CLOCK_PHASE_LAYOUT &&
                       (priv->requested & GDK_FRAME_CLOCK_PHASE_LAYOUT))
@@ -435,7 +531,7 @@ gdk_frame_clock_paint_idle (void *data)
           if (priv->freeze_count == 0)
             {
 #ifdef G_ENABLE_DEBUG
-              if (GDK_DEBUG_CHECK (FRAMES))
+              if (GDK_DEBUG_CHECK (FRAMES) || gdk_profiler_is_running ())
                 {
                   if (priv->phase != GDK_FRAME_CLOCK_PHASE_PAINT &&
                       (priv->requested & GDK_FRAME_CLOCK_PHASE_PAINT))
@@ -462,7 +558,7 @@ gdk_frame_clock_paint_idle (void *data)
               priv->phase = GDK_FRAME_CLOCK_PHASE_NONE;
 
 #ifdef G_ENABLE_DEBUG
-              if (GDK_DEBUG_CHECK (FRAMES))
+              if (GDK_DEBUG_CHECK (FRAMES) || gdk_profiler_is_running ())
                 timings->frame_end_time = g_get_monotonic_time ();
 #endif /* G_ENABLE_DEBUG */
             }
@@ -475,6 +571,12 @@ gdk_frame_clock_paint_idle (void *data)
     }
 
 #ifdef G_ENABLE_DEBUG
+  if (gdk_profiler_is_running ())
+    {
+      add_timings_to_profiler (timings);
+      gdk_profiler_set_counter (fps_counter, timings->frame_end_time * 1000, frame_clock_get_fps (clock)); 
+    }
+
   if (GDK_DEBUG_CHECK (FRAMES))
     {
       if (timings && timings->complete)