SurfaceFlinger: add a test for unknown offset

Add a unit test that tries to get phase offset for a
refresh rate that is not part of the boot list.
The scenarios simulates an external display hotplug
with different refresh rate than the internal one.

Bug: 151859083
Test: adb shell /data/nativetest64/libsurfaceflinger_unittest/libsurfaceflinger_unittest
Change-Id: I3adee92b91d0c1a337c9a6ffd7431e7b854bbe0d
diff --git a/services/surfaceflinger/Scheduler/PhaseOffsets.cpp b/services/surfaceflinger/Scheduler/PhaseOffsets.cpp
index 7941cda..43883fb 100644
--- a/services/surfaceflinger/Scheduler/PhaseOffsets.cpp
+++ b/services/surfaceflinger/Scheduler/PhaseOffsets.cpp
@@ -36,6 +36,19 @@
     return std::abs(fpsA - fpsB) <= MARGIN;
 }
 
+std::vector<float> getRefreshRatesFromConfigs(
+        const android::scheduler::RefreshRateConfigs& refreshRateConfigs) {
+    const auto& allRefreshRates = refreshRateConfigs.getAllRefreshRates();
+    std::vector<float> refreshRates;
+    refreshRates.reserve(allRefreshRates.size());
+
+    for (const auto& [ignored, refreshRate] : allRefreshRates) {
+        refreshRates.emplace_back(refreshRate->fps);
+    }
+
+    return refreshRates;
+}
+
 } // namespace
 
 namespace android::scheduler {
@@ -45,14 +58,21 @@
 namespace impl {
 
 PhaseOffsets::PhaseOffsets(const scheduler::RefreshRateConfigs& refreshRateConfigs)
-      : // Below defines the threshold when an offset is considered to be negative, i.e. targeting
-        // for the N+2 vsync instead of N+1. This means that:
-        // For offset < threshold, SF wake up (vsync_duration - offset) before HW vsync.
-        // For offset >= threshold, SF wake up (2 * vsync_duration - offset) before HW vsync.
-        mThresholdForNextVsync(getProperty("debug.sf.phase_offset_threshold_for_next_vsync_ns")
-                                       .value_or(std::numeric_limits<nsecs_t>::max())),
-        mOffsets(initializeOffsets(refreshRateConfigs)),
-        mRefreshRateFps(refreshRateConfigs.getCurrentRefreshRate().fps) {}
+      : PhaseOffsets(getRefreshRatesFromConfigs(refreshRateConfigs),
+                     refreshRateConfigs.getCurrentRefreshRate().fps,
+                     // Below defines the threshold when an offset is considered to be negative,
+                     // i.e. targeting for the N+2 vsync instead of N+1. This means that: For offset
+                     // < threshold, SF wake up (vsync_duration - offset) before HW vsync. For
+                     // offset >= threshold, SF wake up (2 * vsync_duration - offset) before HW
+                     // vsync.
+                     getProperty("debug.sf.phase_offset_threshold_for_next_vsync_ns")
+                             .value_or(std::numeric_limits<nsecs_t>::max())) {}
+
+PhaseOffsets::PhaseOffsets(const std::vector<float>& refreshRates, float currentFps,
+                           nsecs_t thresholdForNextVsync)
+      : mThresholdForNextVsync(thresholdForNextVsync),
+        mOffsets(initializeOffsets(refreshRates)),
+        mRefreshRateFps(currentFps) {}
 
 void PhaseOffsets::dump(std::string& result) const {
     const auto [early, earlyGl, late] = getCurrentOffsets();
@@ -67,12 +87,12 @@
 }
 
 std::unordered_map<float, PhaseOffsets::Offsets> PhaseOffsets::initializeOffsets(
-        const scheduler::RefreshRateConfigs& refreshRateConfigs) const {
+        const std::vector<float>& refreshRates) const {
     std::unordered_map<float, Offsets> offsets;
 
-    for (const auto& [ignored, refreshRate] : refreshRateConfigs.getAllRefreshRates()) {
-        const float fps = refreshRate->fps;
-        offsets.emplace(fps, getPhaseOffsets(fps, refreshRate->vsyncPeriod));
+    for (const auto& refreshRate : refreshRates) {
+        offsets.emplace(refreshRate,
+                        getPhaseOffsets(refreshRate, static_cast<nsecs_t>(1e9f / refreshRate)));
     }
     return offsets;
 }
@@ -243,19 +263,6 @@
     };
 }
 
-static std::vector<float> getRefreshRatesFromConfigs(
-        const android::scheduler::RefreshRateConfigs& refreshRateConfigs) {
-    const auto& allRefreshRates = refreshRateConfigs.getAllRefreshRates();
-    std::vector<float> refreshRates;
-    refreshRates.reserve(allRefreshRates.size());
-
-    for (const auto& [ignored, refreshRate] : allRefreshRates) {
-        refreshRates.emplace_back(refreshRate->fps);
-    }
-
-    return refreshRates;
-}
-
 std::unordered_map<float, PhaseDurations::Offsets> PhaseDurations::initializeOffsets(
         const std::vector<float>& refreshRates) const {
     std::unordered_map<float, Offsets> offsets;
diff --git a/services/surfaceflinger/Scheduler/PhaseOffsets.h b/services/surfaceflinger/Scheduler/PhaseOffsets.h
index 208f06b..fa8011d 100644
--- a/services/surfaceflinger/Scheduler/PhaseOffsets.h
+++ b/services/surfaceflinger/Scheduler/PhaseOffsets.h
@@ -66,9 +66,12 @@
     // Returns current offsets in human friendly format.
     void dump(std::string& result) const override;
 
-private:
+protected:
+    // Used for unit tests
+    PhaseOffsets(const std::vector<float>& refreshRates, float currentFps,
+                 nsecs_t thresholdForNextVsync);
     std::unordered_map<float, Offsets> initializeOffsets(
-            const scheduler::RefreshRateConfigs&) const;
+            const std::vector<float>& refreshRates) const;
     Offsets getDefaultOffsets(nsecs_t vsyncPeriod) const;
     Offsets getHighFpsOffsets(nsecs_t vsyncPeriod) const;
     Offsets getPhaseOffsets(float fps, nsecs_t vsyncPeriod) const;
diff --git a/services/surfaceflinger/tests/unittests/PhaseOffsetsTest.cpp b/services/surfaceflinger/tests/unittests/PhaseOffsetsTest.cpp
index 910e73b..8d49201 100644
--- a/services/surfaceflinger/tests/unittests/PhaseOffsetsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/PhaseOffsetsTest.cpp
@@ -42,25 +42,25 @@
                                  appEarlyGlDuration) {}
 };
 
-class PhaseOffsetsTest : public testing::Test {
+class PhaseDurationTest : public testing::Test {
 protected:
-    PhaseOffsetsTest()
-          : mPhaseOffsets(60.0f, 10'500'000, 20'500'000, 16'000'000, 33'500'000, 13'500'000,
-                          38'000'000) {}
+    PhaseDurationTest()
+          : mPhaseDurations(60.0f, 10'500'000, 20'500'000, 16'000'000, 33'500'000, 13'500'000,
+                            38'000'000) {}
 
-    ~PhaseOffsetsTest() = default;
+    ~PhaseDurationTest() = default;
 
-    TestablePhaseOffsetsAsDurations mPhaseOffsets;
+    TestablePhaseOffsetsAsDurations mPhaseDurations;
 };
 
 namespace {
 /* ------------------------------------------------------------------------
  * Test cases
  */
-TEST_F(PhaseOffsetsTest, getOffsetsForRefreshRate_60Hz) {
-    mPhaseOffsets.setRefreshRateFps(60.0f);
-    auto currentOffsets = mPhaseOffsets.getCurrentOffsets();
-    auto offsets = mPhaseOffsets.getOffsetsForRefreshRate(60.0f);
+TEST_F(PhaseDurationTest, getOffsetsForRefreshRate_60Hz) {
+    mPhaseDurations.setRefreshRateFps(60.0f);
+    auto currentOffsets = mPhaseDurations.getCurrentOffsets();
+    auto offsets = mPhaseDurations.getOffsetsForRefreshRate(60.0f);
 
     EXPECT_EQ(currentOffsets, offsets);
     EXPECT_EQ(offsets.late.sf, 6'166'667);
@@ -76,10 +76,10 @@
     EXPECT_EQ(offsets.earlyGl.app, 15'166'668);
 }
 
-TEST_F(PhaseOffsetsTest, getOffsetsForRefreshRate_90Hz) {
-    mPhaseOffsets.setRefreshRateFps(90.0f);
-    auto currentOffsets = mPhaseOffsets.getCurrentOffsets();
-    auto offsets = mPhaseOffsets.getOffsetsForRefreshRate(90.0f);
+TEST_F(PhaseDurationTest, getOffsetsForRefreshRate_90Hz) {
+    mPhaseDurations.setRefreshRateFps(90.0f);
+    auto currentOffsets = mPhaseDurations.getCurrentOffsets();
+    auto offsets = mPhaseDurations.getOffsetsForRefreshRate(90.0f);
 
     EXPECT_EQ(currentOffsets, offsets);
     EXPECT_EQ(offsets.late.sf, 611'111);
@@ -95,7 +95,7 @@
     EXPECT_EQ(offsets.earlyGl.app, 4'055'555);
 }
 
-TEST_F(PhaseOffsetsTest, getOffsetsForRefreshRate_DefaultOffsets) {
+TEST_F(PhaseDurationTest, getOffsetsForRefreshRate_DefaultOffsets) {
     TestablePhaseOffsetsAsDurations phaseOffsetsWithDefaultValues(60.0f, -1, -1, -1, -1, -1, -1);
 
     auto validateOffsets = [](auto& offsets) {
@@ -125,6 +125,54 @@
     validateOffsets(offsets);
 }
 
+TEST_F(PhaseDurationTest, getOffsetsForRefreshRate_unknownRefreshRate) {
+    auto offsets = mPhaseDurations.getOffsetsForRefreshRate(14.7f);
+
+    EXPECT_EQ(offsets.late.sf, 57'527'208);
+
+    EXPECT_EQ(offsets.late.app, 37'027'208);
+
+    EXPECT_EQ(offsets.early.sf, 52'027'208);
+
+    EXPECT_EQ(offsets.early.app, 18'527'208);
+
+    EXPECT_EQ(offsets.earlyGl.sf, 54'527'208);
+
+    EXPECT_EQ(offsets.earlyGl.app, 16'527'208);
+}
+
+} // namespace
+
+class TestablePhaseOffsets : public impl::PhaseOffsets {
+public:
+    TestablePhaseOffsets() : impl::PhaseOffsets({60.0f, 90.0f}, 60.0f, 10'000'000) {}
+};
+
+class PhaseOffsetsTest : public testing::Test {
+protected:
+    PhaseOffsetsTest() = default;
+    ~PhaseOffsetsTest() = default;
+
+    TestablePhaseOffsets mPhaseOffsets;
+};
+
+namespace {
+TEST_F(PhaseOffsetsTest, getOffsetsForRefreshRate_unknownRefreshRate) {
+    auto offsets = mPhaseOffsets.getOffsetsForRefreshRate(14.7f);
+
+    EXPECT_EQ(offsets.late.sf, 1'000'000);
+
+    EXPECT_EQ(offsets.late.app, 1'000'000);
+
+    EXPECT_EQ(offsets.early.sf, 1'000'000);
+
+    EXPECT_EQ(offsets.early.app, 1'000'000);
+
+    EXPECT_EQ(offsets.earlyGl.sf, 1'000'000);
+
+    EXPECT_EQ(offsets.earlyGl.app, 1'000'000);
+}
+
 } // namespace
 } // namespace scheduler
 } // namespace android