commit 6da0e492c1cdf673111b439655bd071cfce0a042
author Ana Krulec <akrulec@google.com> Tue Feb 19 14:46:01 2019 -0800
committer Ana Krulec <akrulec@google.com> Tue Feb 19 16:38:28 2019 -0800
tree a25ad43ced95fd0f25d9a4d47105f83cdeaf6f3d
parent 38929e14a9eda7c6c6e7f3820cff3b450328f3ae

SF: Add a lock guard to mLayerHistory

Test: forrest
Bug: 124760910
Bug: 124660613
Change-Id: I2275f6abf52369c84e7f2d3bb77d6eb7c597b892

services/surfaceflinger/Scheduler/Scheduler.cpp

diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 30fba3c..f792f1e 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -293,6 +293,7 @@
 }
 
 void Scheduler::incrementFrameCounter() {
+    std::lock_guard<std::mutex> lock(mLayerHistoryLock);
     mLayerHistory.incrementCounter();
 }
 
@@ -317,25 +318,28 @@
 
 void Scheduler::determineLayerTimestampStats(const std::string layerName,
                                              const nsecs_t framePresentTime) {
-    mLayerHistory.insert(layerName, framePresentTime);
     std::vector<int64_t> differencesMs;
-
-    // Traverse through the layer history, and determine the differences in present times.
-    nsecs_t newestPresentTime = framePresentTime;
     std::string differencesText = "";
-    for (int i = 1; i < mLayerHistory.getSize(); i++) {
-        std::unordered_map<std::string, nsecs_t> layers = mLayerHistory.get(i);
-        for (auto layer : layers) {
-            if (layer.first != layerName) {
-                continue;
+    {
+        std::lock_guard<std::mutex> lock(mLayerHistoryLock);
+        mLayerHistory.insert(layerName, framePresentTime);
+
+        // Traverse through the layer history, and determine the differences in present times.
+        nsecs_t newestPresentTime = framePresentTime;
+        for (int i = 1; i < mLayerHistory.getSize(); i++) {
+            std::unordered_map<std::string, nsecs_t> layers = mLayerHistory.get(i);
+            for (auto layer : layers) {
+                if (layer.first != layerName) {
+                    continue;
+                }
+                int64_t differenceMs = (newestPresentTime - layer.second) / 1000000;
+                // Dismiss noise.
+                if (differenceMs > 10 && differenceMs < 60) {
+                    differencesMs.push_back(differenceMs);
+                }
+                IF_ALOGV() { differencesText += (std::to_string(differenceMs) + " "); }
+                newestPresentTime = layer.second;
             }
-            int64_t differenceMs = (newestPresentTime - layer.second) / 1000000;
-            // Dismiss noise.
-            if (differenceMs > 10 && differenceMs < 60) {
-                differencesMs.push_back(differenceMs);
-            }
-            IF_ALOGV() { differencesText += (std::to_string(differenceMs) + " "); }
-            newestPresentTime = layer.second;
         }
     }
     ALOGV("Layer %s timestamp intervals: %s", layerName.c_str(), differencesText.c_str());