Revert of "Route DXGI Frame Statistics to VSyncProvider"

ui/gl/sync_control_vsync_provider.cc

Index: ui/gl/sync_control_vsync_provider.cc
diff --git a/ui/gl/sync_control_vsync_provider.cc b/ui/gl/sync_control_vsync_provider.cc
index e181d70eb179340835e68d0039d2faf3c4ad0ad5..f9dc5c56e47e7e0a0a64eacc06d6f960ab83ea8e 100644
--- a/ui/gl/sync_control_vsync_provider.cc
+++ b/ui/gl/sync_control_vsync_provider.cc
@@ -11,7 +11,7 @@
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 
-#if defined(OS_LINUX) || defined(OS_WIN)
+#if defined(OS_LINUX)
 // These constants define a reasonable range for a calculated refresh interval.
 // Calculating refreshes out of this range will be considered a fatal error.
 const int64_t kMinVsyncIntervalUs = base::Time::kMicrosecondsPerSecond / 400;
@@ -21,17 +21,17 @@ const int64_t kMaxVsyncIntervalUs = base::Time::kMicrosecondsPerSecond / 10;
 // we think the latest computed interval is invalid (noisey due to
 // monitor configuration change, moving a window between monitors, etc.).
 const double kRelativeIntervalDifferenceThreshold = 0.05;
-#endif  // defined(OS_LINUX) || defined(OS_WIN)
+#endif
 
 namespace gl {
 
 SyncControlVSyncProvider::SyncControlVSyncProvider() : gfx::VSyncProvider() {
-#if defined(OS_LINUX) || defined(OS_WIN)
+#if defined(OS_LINUX)
   // On platforms where we can't get an accurate reading on the refresh
   // rate we fall back to the assumption that we're displaying 60 frames
   // per second.
   last_good_interval_ = base::TimeDelta::FromSeconds(1) / 60;
-#endif  // defined(OS_LINUX) || defined(OS_WIN)
+#endif
 }
 
 SyncControlVSyncProvider::~SyncControlVSyncProvider() {}
@@ -39,121 +39,33 @@ SyncControlVSyncProvider::~SyncControlVSyncProvider() {}
 void SyncControlVSyncProvider::GetVSyncParameters(
     const UpdateVSyncCallback& callback) {
   TRACE_EVENT0("gpu", "SyncControlVSyncProvider::GetVSyncParameters");
-#if defined(OS_LINUX) || defined(OS_WIN)
+#if defined(OS_LINUX)
   base::TimeTicks timebase;
 
+  // The actual clock used for the system time returned by glXGetSyncValuesOML
+  // is unspecified. In practice, the clock used is likely to be either
+  // CLOCK_REALTIME or CLOCK_MONOTONIC, so we compare the returned time to the
+  // current time according to both clocks, and assume that the returned time
+  // was produced by the clock whose current time is closest to it, subject
+  // to the restriction that the returned time must not be in the future
+  // (since it is the time of a vblank that has already occurred).
   int64_t system_time;
   int64_t media_stream_counter;
   int64_t swap_buffer_counter;
   if (!GetSyncValues(&system_time, &media_stream_counter, &swap_buffer_counter))
     return;
 
-  if (media_stream_counter == last_media_stream_counter_) {
-    // SyncValues haven't updated, there is no reason to invoke the callback.
-    return;
-  }
-
-  // Perform platform specific adjustment of |system_time| and
-  // |media_stream_counter|.
-  if (!AdjustSyncValues(&system_time, &media_stream_counter))
-    return;
-
-  timebase = base::TimeTicks::FromInternalValue(system_time);
-
-  // Only need the previous calculated interval for our filtering.
-  while (last_computed_intervals_.size() > 1)
-    last_computed_intervals_.pop();
-
-  base::TimeDelta timebase_diff;
-  int64_t counter_diff = 0;
-
-  int32_t numerator, denominator;
-  if (GetMscRate(&numerator, &denominator) && numerator) {
-    timebase_diff = base::TimeDelta::FromSeconds(denominator);
-    counter_diff = numerator;
-  } else if (!last_timebase_.is_null()) {
-    timebase_diff = timebase - last_timebase_;
-    counter_diff = media_stream_counter - last_media_stream_counter_;
-  }
-
-  if (counter_diff > 0 && timebase_diff > base::TimeDelta()) {
-    last_computed_intervals_.push(timebase_diff / counter_diff);
-
-    if (last_computed_intervals_.size() == 2) {
-      const base::TimeDelta& old_interval = last_computed_intervals_.front();
-      const base::TimeDelta& new_interval = last_computed_intervals_.back();
-
-      double relative_change = fabs(old_interval.InMillisecondsF() -
-                                    new_interval.InMillisecondsF()) /
-                               new_interval.InMillisecondsF();
-      if (relative_change < kRelativeIntervalDifferenceThreshold) {
-        if (new_interval.InMicroseconds() < kMinVsyncIntervalUs ||
-            new_interval.InMicroseconds() > kMaxVsyncIntervalUs) {
-#if defined(OS_WIN) || defined(USE_ASH)
-          // On ash platforms (ChromeOS essentially), the real refresh interval
-          // is queried from XRandR, regardless of the value calculated here,
-          // and this value is overriden by ui::CompositorVSyncManager.  The log
-          // should not be fatal in this case. Reconsider all this when XRandR
-          // support is added to non-ash platforms.
-          // http://crbug.com/340851
-          // On Windows |system_time| is based on QPC and it seems it may
-          // produce invalid value after a suspend/resume cycle.
-          // http://crbug.com/656469
-          LOG(ERROR)
-#else
-          LOG(FATAL)
-#endif  // OS_WIN || USE_ASH
-              << "Calculated bogus refresh interval="
-              << new_interval.InMicroseconds()
-              << " us, old_interval=" << old_interval.InMicroseconds()
-              << " us, last_timebase_=" << last_timebase_.ToInternalValue()
-              << " us, timebase=" << timebase.ToInternalValue()
-              << " us, timebase_diff=" << timebase_diff.ToInternalValue()
-              << " us, last_timebase_diff_="
-              << last_timebase_diff_.ToInternalValue()
-              << " us, last_media_stream_counter_="
-              << last_media_stream_counter_
-              << ", media_stream_counter=" << media_stream_counter
-              << ", counter_diff=" << counter_diff
-              << ", last_counter_diff_=" << last_counter_diff_;
-        } else {
-          last_good_interval_ = new_interval;
-        }
-      }
-    }
-
-    last_timebase_diff_ = timebase_diff;
-    last_counter_diff_ = counter_diff;
-  }
-
-  last_timebase_ = timebase;
-  last_media_stream_counter_ = media_stream_counter;
-  callback.Run(timebase, last_good_interval_);
-#endif  // defined(OS_LINUX) || defined(OS_WIN)
-}
-
-#if defined(OS_LINUX)
-bool SyncControlVSyncProvider::AdjustSyncValues(int64_t* system_time,
-                                                int64_t* media_stream_counter) {
   // Both Intel and Mali drivers will return TRUE for GetSyncValues
   // but a value of 0 for MSC if they cannot access the CRTC data structure
   // associated with the surface. crbug.com/231945
   bool prev_invalid_msc = invalid_msc_;
-  invalid_msc_ = (*media_stream_counter == 0);
+  invalid_msc_ = (media_stream_counter == 0);
   if (invalid_msc_) {
-    LOG_IF(ERROR, !prev_invalid_msc)
-        << "glXGetSyncValuesOML "
-           "should not return TRUE with a media stream counter of 0.";
-    return false;
+    LOG_IF(ERROR, !prev_invalid_msc) << "glXGetSyncValuesOML "
+        "should not return TRUE with a media stream counter of 0.";
+    return;
   }
 
-  // The actual clock used for the system time returned by glXGetSyncValuesOML
-  // is unspecified. In practice, the clock used is likely to be either
-  // CLOCK_REALTIME or CLOCK_MONOTONIC, so we compare the returned time to the
-  // current time according to both clocks, and assume that the returned time
-  // was produced by the clock whose current time is closest to it, subject
-  // to the restriction that the returned time must not be in the future
-  // (since it is the time of a vblank that has already occurred).
   struct timespec real_time;
   struct timespec monotonic_time;
   clock_gettime(CLOCK_REALTIME, &real_time);
@@ -169,62 +81,81 @@ bool SyncControlVSyncProvider::AdjustSyncValues(int64_t* system_time,
   // We need the time according to CLOCK_MONOTONIC, so if we've been given
   // a time from CLOCK_REALTIME, we need to convert.
   bool time_conversion_needed =
-      llabs(*system_time - real_time_in_microseconds) <
-      llabs(*system_time - monotonic_time_in_microseconds);
+      llabs(system_time - real_time_in_microseconds) <
+      llabs(system_time - monotonic_time_in_microseconds);
 
   if (time_conversion_needed)
-    *system_time += monotonic_time_in_microseconds - real_time_in_microseconds;
+    system_time += monotonic_time_in_microseconds - real_time_in_microseconds;
 
-  // Return if |*system_time| is more than 1 frames in the future.
+  // Return if |system_time| is more than 1 frames in the future.
   int64_t interval_in_microseconds = last_good_interval_.InMicroseconds();
-  if (*system_time > monotonic_time_in_microseconds + interval_in_microseconds)
-    return false;
+  if (system_time > monotonic_time_in_microseconds + interval_in_microseconds)
+    return;
 
   // If |system_time| is slightly in the future, adjust it to the previous
   // frame and use the last frame counter to prevent issues in the callback.
-  if (*system_time > monotonic_time_in_microseconds) {
-    *system_time -= interval_in_microseconds;
-    (*media_stream_counter)--;
+  if (system_time > monotonic_time_in_microseconds) {
+    system_time -= interval_in_microseconds;
+    media_stream_counter--;
   }
-  if (monotonic_time_in_microseconds - *system_time >
+  if (monotonic_time_in_microseconds - system_time >
       base::Time::kMicrosecondsPerSecond)
-    return false;
+    return;
 
-  return true;
-}
-#endif  // defined(OS_LINUX)
+  timebase = base::TimeTicks::FromInternalValue(system_time);
 
-#if defined(OS_WIN)
-bool SyncControlVSyncProvider::AdjustSyncValues(int64_t* system_time,
-                                                int64_t* media_stream_counter) {
-  // Zero MSC is returned once when switching between windowed and full screen
-  // modes.
-  if (*media_stream_counter == 0)
-    return false;
-
-  // The actual clock used for the system time returned by glXGetSyncValuesEGL
-  // is unspecified. In practice, the clock comes from QueryPerformanceCounter.
-  LARGE_INTEGER perf_counter_now = {};
-  ::QueryPerformanceCounter(&perf_counter_now);
-  int64_t qpc_now =
-      base::TimeDelta::FromQPCValue(perf_counter_now.QuadPart).InMicroseconds();
+  // Only need the previous calculated interval for our filtering.
+  while (last_computed_intervals_.size() > 1)
+    last_computed_intervals_.pop();
 
-  // Return if |system_time| is more than 1 frames in the future.
-  int64_t interval_in_microseconds = last_good_interval_.InMicroseconds();
-  if (*system_time > qpc_now + interval_in_microseconds)
-    return false;
+  int32_t numerator, denominator;
+  if (GetMscRate(&numerator, &denominator) && numerator) {
+    last_computed_intervals_.push(base::TimeDelta::FromSeconds(denominator) /
+                                  numerator);
+  } else if (!last_timebase_.is_null()) {
+    base::TimeDelta timebase_diff = timebase - last_timebase_;
+    int64_t counter_diff = media_stream_counter - last_media_stream_counter_;
+    if (counter_diff > 0 && timebase > last_timebase_)
+      last_computed_intervals_.push(timebase_diff / counter_diff);
+  }
 
-  // If |system_time| is slightly in the future, adjust it to the previous
-  // frame and use the last frame counter to prevent issues in the callback.
-  if (*system_time > qpc_now) {
-    *system_time -= interval_in_microseconds;
-    (*media_stream_counter)--;
+  if (last_computed_intervals_.size() == 2) {
+    const base::TimeDelta& old_interval = last_computed_intervals_.front();
+    const base::TimeDelta& new_interval = last_computed_intervals_.back();
+
+    double relative_change =
+        fabs(old_interval.InMillisecondsF() - new_interval.InMillisecondsF()) /
+        new_interval.InMillisecondsF();
+    if (relative_change < kRelativeIntervalDifferenceThreshold) {
+      if (new_interval.InMicroseconds() < kMinVsyncIntervalUs ||
+          new_interval.InMicroseconds() > kMaxVsyncIntervalUs) {
+#if defined(USE_ASH)
+        // On ash platforms (ChromeOS essentially), the real refresh interval is
+        // queried from XRandR, regardless of the value calculated here, and
+        // this value is overriden by ui::CompositorVSyncManager.  The log
+        // should not be fatal in this case. Reconsider all this when XRandR
+        // support is added to non-ash platforms.
+        // http://crbug.com/340851
+        LOG(ERROR)
+#else
+        LOG(FATAL)
+#endif  // USE_ASH
+            << "Calculated bogus refresh interval="
+            << new_interval.InMicroseconds()
+            << " us., last_timebase_=" << last_timebase_.ToInternalValue()
+            << " us., timebase=" << timebase.ToInternalValue()
+            << " us., last_media_stream_counter_=" << last_media_stream_counter_
+            << ", media_stream_counter=" << media_stream_counter;
+      } else {
+        last_good_interval_ = new_interval;
+      }
+    }
   }
-  if (qpc_now - *system_time > base::Time::kMicrosecondsPerSecond)
-    return false;
 
-  return true;
+  last_timebase_ = timebase;
+  last_media_stream_counter_ = media_stream_counter;
+  callback.Run(timebase, last_good_interval_);
+#endif  // defined(OS_LINUX)
 }
-#endif  // defined(OS_WIN)
 
 }  // namespace gl