diff --git a/compositor/drmdisplaycompositor.cpp b/compositor/drmdisplaycompositor.cpp
index 401af48..1519736 100644
--- a/compositor/drmdisplaycompositor.cpp
+++ b/compositor/drmdisplaycompositor.cpp
@@ -23,6 +23,7 @@
 #include <sched.h>
 #include <stdlib.h>
 #include <time.h>
+#include <array>
 #include <sstream>
 #include <vector>
 
@@ -40,6 +41,15 @@
 
 namespace android {
 
+std::ostream &operator<<(std::ostream &str, FlatteningState state) {
+  std::array<const char *, 6> flattenting_state_str = {
+      "None",   "Not needed", "SF Requested", "Squashed by GPU",
+      "Serial", "Concurrent",
+  };
+
+  return str << flattenting_state_str[static_cast<int>(state)];
+}
+
 class CompositorVsyncCallback : public VsyncCallback {
  public:
   CompositorVsyncCallback(DrmDisplayCompositor *compositor)
@@ -64,7 +74,8 @@
       dump_last_timestamp_ns_(0),
       flatten_countdown_(FLATTEN_COUNTDOWN_INIT),
       writeback_fence_(-1),
-      flattening_state_(FlatteningState::kNone) {
+      flattening_state_(FlatteningState::kNone),
+      frames_flattened_(0) {
   struct timespec ts;
   if (clock_gettime(CLOCK_MONOTONIC, &ts))
     return;
@@ -148,6 +159,10 @@
   return flattening_state_;
 }
 
+uint32_t DrmDisplayCompositor::GetFlattenedFramesCount() const {
+  return frames_flattened_;
+}
+
 bool DrmDisplayCompositor::ShouldFlattenOnClient() const {
   return flattening_state_ == FlatteningState::kClientRequested ||
          flattening_state_ == FlatteningState::kClientDone;
@@ -616,9 +631,9 @@
 
   flatten_countdown_ = FLATTEN_COUNTDOWN_INIT;
   if (flattening_state_ != FlatteningState::kClientRequested) {
-    flattening_state_ = FlatteningState::kNone;
+    SetFlattening(FlatteningState::kNone);
   } else {
-    flattening_state_ = FlatteningState::kClientDone;
+    SetFlattening(FlatteningState::kClientDone);
   }
   vsync_worker_.VSyncControl(!writeback);
 }
@@ -776,6 +791,23 @@
   return 0;
 }
 
+void DrmDisplayCompositor::SetFlattening(FlatteningState new_state) {
+  if (flattening_state_ != new_state) {
+    switch (flattening_state_) {
+      case FlatteningState::kClientDone:
+      case FlatteningState::kConcurrent:
+      case FlatteningState::kSerial:
+        ++frames_flattened_;
+        break;
+      case FlatteningState::kClientRequested:
+      case FlatteningState::kNone:
+      case FlatteningState::kNotNeeded:
+        break;
+    }
+  }
+  flattening_state_ = new_state;
+}
+
 bool DrmDisplayCompositor::IsFlatteningNeeded() const {
   return CountdownExpired() && active_composition_->layers().size() >= 2;
 }
@@ -787,7 +819,7 @@
       if (!IsFlatteningNeeded()) {
         if (flattening_state_ != FlatteningState::kClientDone) {
           ALOGV("Flattening is not needed");
-          flattening_state_ = FlatteningState::kNotNeeded;
+          SetFlattening(FlatteningState::kNotNeeded);
         }
         return -EALREADY;
       }
@@ -796,7 +828,7 @@
     ALOGV(
         "No writeback connector available, "
         "falling back to client composition");
-    flattening_state_ = FlatteningState::kClientRequested;
+    SetFlattening(FlatteningState::kClientRequested);
     refresh_display_cb_(display_);
     return 0;
   } else {
@@ -822,7 +854,7 @@
     return ret;
   if (!IsFlatteningNeeded()) {
     ALOGV("Flattening is not needed");
-    flattening_state_ = FlatteningState::kNotNeeded;
+    SetFlattening(FlatteningState::kNotNeeded);
     return -EALREADY;
   }
 
@@ -931,7 +963,7 @@
     return ret;
   if (!IsFlatteningNeeded()) {
     ALOGV("Flattening is not needed");
-    flattening_state_ = FlatteningState::kNotNeeded;
+    SetFlattening(FlatteningState::kNotNeeded);
     return -EALREADY;
   }
   DrmCrtc *crtc = active_composition_->crtc();
@@ -1007,10 +1039,10 @@
   }
 
   if (writeback_conn->display() != display_) {
-    flattening_state_ = FlatteningState::kConcurrent;
+    SetFlattening(FlatteningState::kConcurrent);
     return FlattenConcurrent(writeback_conn);
   } else {
-    flattening_state_ = FlatteningState::kSerial;
+    SetFlattening(FlatteningState::kSerial);
     return FlattenSerial(writeback_conn);
   }
 
diff --git a/drmhwctwo.cpp b/drmhwctwo.cpp
index a4a8187..605406b 100644
--- a/drmhwctwo.cpp
+++ b/drmhwctwo.cpp
@@ -142,6 +142,7 @@
           << ((delta.failed_kms_present_ > 0)
                   ? " !!! Internal failure, FIX it please\n"
                   : "")
+          << " Flattened frames: " << delta.frames_flattened_ << "\n"
           << " Pixel operations (free units)"
           << " : [TOTAL: " << delta.total_pixops_
           << " / GPU: " << delta.gpu_pixops_ << "]\n"
@@ -152,6 +153,8 @@
 std::string DrmHwcTwo::HwcDisplay::Dump() {
   auto out = (std::stringstream()
               << "- Display on: " << connector_->name() << "\n"
+              << "  Flattening state: " << compositor_.GetFlatteningState()
+              << "\n"
               << "Statistics since system boot:\n"
               << DumpDelta(total_stats_) << "\n\n"
               << "Statistics since last dumpsys request:\n"
@@ -970,6 +973,7 @@
 
   *num_types = client_size;
 
+  total_stats_.frames_flattened_ = compositor_.GetFlattenedFramesCount();
   total_stats_.gpu_pixops_ += gpu_pixops;
   total_stats_.total_pixops_ += total_pixops;
 
diff --git a/include/drmdisplaycompositor.h b/include/drmdisplaycompositor.h
index cfd8f4a..26e2572 100644
--- a/include/drmdisplaycompositor.h
+++ b/include/drmdisplaycompositor.h
@@ -50,6 +50,8 @@
   kConcurrent
 };
 
+std::ostream &operator<<(std::ostream &str, FlatteningState state);
+
 class DrmDisplayCompositor {
  public:
   DrmDisplayCompositor();
@@ -77,6 +79,7 @@
   }
 
   FlatteningState GetFlatteningState() const;
+  uint32_t GetFlattenedFramesCount() const;
   bool ShouldFlattenOnClient() const;
 
   std::tuple<uint32_t, uint32_t, int> GetActiveModeResolution();
@@ -108,6 +111,7 @@
   void ApplyFrame(std::unique_ptr<DrmDisplayComposition> composition,
                   int status, bool writeback = false);
 
+  void SetFlattening(FlatteningState new_state);
   bool IsFlatteningNeeded() const;
   int FlattenActiveComposition();
   int FlattenOnClient();
@@ -148,6 +152,7 @@
   int writeback_fence_;
 
   FlatteningState flattening_state_;
+  uint32_t frames_flattened_;
 
   std::function<void(int)> refresh_display_cb_;
 };
diff --git a/include/drmhwctwo.h b/include/drmhwctwo.h
index 43f1fce..2bbe334 100644
--- a/include/drmhwctwo.h
+++ b/include/drmhwctwo.h
@@ -260,9 +260,11 @@
     struct Stats {
       Stats minus(Stats b) {
         return {total_frames_ - b.total_frames_,
-                total_pixops_ - b.total_pixops_, gpu_pixops_ - b.gpu_pixops_,
+                total_pixops_ - b.total_pixops_,
+                gpu_pixops_ - b.gpu_pixops_,
                 failed_kms_validate_ - b.failed_kms_validate_,
-                failed_kms_present_ - b.failed_kms_present_};
+                failed_kms_present_ - b.failed_kms_present_,
+                frames_flattened_ - b.frames_flattened_};
       }
 
       uint32_t total_frames_ = 0;
@@ -270,6 +272,7 @@
       uint64_t gpu_pixops_ = 0;
       uint32_t failed_kms_validate_ = 0;
       uint32_t failed_kms_present_ = 0;
+      uint32_t frames_flattened_ = 0;
     } total_stats_, prev_stats_;
     std::string DumpDelta(DrmHwcTwo::HwcDisplay::Stats delta);
   };