[mutter] clutter/frame-clock: Add presented profile trace

[Marge Bot <marge-bot src gnome org>]

commit e10084199bbd836de8850efa648bfad390e139a3
Author: Ivan Molodetskikh <yalterz gmail com>
Date:   Tue Dec 14 12:32:42 2021 +0300

    clutter/frame-clock: Add presented profile trace
    
    In addition to the presented callback time, it shows the time to the
    reported presentation time (which can be earlier or later than the
    presented callback), as well as the GPU rendering duration.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1928>

 clutter/clutter/clutter-frame-clock.c | 42 +++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
---
diff --git a/clutter/clutter/clutter-frame-clock.c b/clutter/clutter/clutter-frame-clock.c
index 164e77c083..17bd900370 100644
--- a/clutter/clutter/clutter-frame-clock.c
+++ b/clutter/clutter/clutter-frame-clock.c
@@ -228,6 +228,48 @@ void
 clutter_frame_clock_notify_presented (ClutterFrameClock *frame_clock,
                                       ClutterFrameInfo  *frame_info)
 {
+  COGL_TRACE_BEGIN_SCOPED (ClutterFrameClockNotifyPresented,
+                           "Frame Clock (presented)");
+
+#ifdef COGL_HAS_TRACING
+  if (G_UNLIKELY (cogl_is_tracing_enabled ()))
+    {
+      int64_t current_time_us;
+      g_autoptr (GString) description = NULL;
+
+      current_time_us = g_get_monotonic_time ();
+      description = g_string_new (NULL);
+
+      if (frame_info->presentation_time != 0)
+        {
+          if (frame_info->presentation_time <= current_time_us)
+            {
+              g_string_append_printf (description,
+                                      "presentation was %ld µs earlier",
+                                      current_time_us - frame_info->presentation_time);
+            }
+          else
+            {
+              g_string_append_printf (description,
+                                      "presentation will be %ld µs later",
+                                      frame_info->presentation_time - current_time_us);
+            }
+        }
+
+      if (frame_info->gpu_rendering_duration_ns != 0)
+        {
+          if (description->len > 0)
+            g_string_append (description, ", ");
+
+          g_string_append_printf (description,
+                                  "buffer swap to GPU done: %ld µs",
+                                  ns2us (frame_info->gpu_rendering_duration_ns));
+        }
+
+      COGL_TRACE_DESCRIBE (ClutterFrameClockNotifyPresented, description->str);
+    }
+#endif
+
   frame_clock->last_presentation_time_us = frame_info->presentation_time;
 
   frame_clock->got_measurements_last_frame = FALSE;