[client] report presentation cadence over LGMP

client/displayservers/Wayland/presentation.c

@@ -56,6 +56,8 @@ static void presentationFeedbackPresented(void * opaque,
     uint32_t tvNsec, uint32_t refresh, uint32_t seqHi, uint32_t seqLo, uint32_t flags)
 {
   struct FrameData * data = opaque;
+  if (refresh)
+    atomic_store(&wlWm.presentationPeriod, refresh);
   struct timespec present = {
     .tv_sec = (uint64_t) tvSecHi << 32 | tvSecLo,
     .tv_nsec = tvNsec,
@@ -69,6 +71,16 @@ static void presentationFeedbackPresented(void * opaque,
   wp_presentation_feedback_destroy(feedback);
 }
 
+bool waylandGetFramePeriod(uint64_t * period)
+{
+  const uint64_t value = atomic_load(&wlWm.presentationPeriod);
+  if (!value)
+    return false;
+
+  *period = value;
+  return true;
+}
+
 static void presentationFeedbackDiscarded(void * data,
     struct wp_presentation_feedback * feedback)
 {

client/displayservers/Wayland/wayland.c

@@ -314,6 +314,7 @@ struct LG_DisplayServerOps LGDS_Wayland =
   .waitFrame           = waylandWaitFrame,
   .skipFrame           = waylandSkipFrame,
   .stopWaitFrame       = waylandStopWaitFrame,
+  .getFramePeriod      = waylandGetFramePeriod,
   .guestPointerUpdated = waylandGuestPointerUpdated,
   .setPointer          = waylandSetPointer,
   .grabPointer         = waylandGrabPointer,

client/displayservers/Wayland/wayland.h

@@ -158,6 +158,7 @@ struct WaylandDSState
 
   struct wp_presentation * presentation;
   clockid_t clkId;
+  _Atomic(uint64_t) presentationPeriod;
   RingBuffer photonTimings;
   GraphHandle photonGraph;
 
@@ -399,6 +400,7 @@ bool waylandPollUnregister(int fd);
 bool waylandPresentationInit(void);
 void waylandPresentationFrame(void);
 void waylandPresentationFree(void);
+bool waylandGetFramePeriod(uint64_t * period);
 
 // registry module
 bool waylandRegistryInit(void);