Stats: added isDeclared return value caching

- reduces the amount of logcat messages from AServiceManager_isDeclared()

Bug: 184056476
Test: build, flash & boot, grep "VINTF manifest" - should be once per app
Change-Id: I13d3671f7b530435ecd6be85d4723607175afafc

1 files changed, 8 insertions, 3 deletions

diff --git a/pixelstats/StatsHelper.cpp b/pixelstats/StatsHelper.cpp
index 28304a8..30899ba 100644
--- a/pixelstats/StatsHelper.cpp
+++ b/pixelstats/StatsHelper.cpp
@@ -36,9 +36,14 @@ const int kVendorAtomOffset = 2;
 
 std::shared_ptr<IStats> getStatsService() {
     const std::string instance = std::string() + IStats::descriptor + "/default";
-    if (!AServiceManager_isDeclared(instance.c_str())) {
-        ALOGE("Stats service is not registered.");
-        return nullptr;
+    static bool isStatsDeclared = false;
+    if (!isStatsDeclared) {
+        // It is good to cache the result - it would not be changed
+        isStatsDeclared = AServiceManager_isDeclared(instance.c_str());
+        if (!isStatsDeclared) {
+            ALOGE("Stats service is not registered.");
+            return nullptr;
+        }
     }
     return IStats::fromBinder(ndk::SpAIBinder(AServiceManager_waitForService(instance.c_str())));
 }