commit a92a56868ea8c5cd1866ca1f6c057f31c5b0b9d9
author Ady Abraham <adyabr@google.com> Tue Jun 07 23:35:38 2022 +0000
committer Ady Abraham <adyabr@google.com> Wed Jun 08 21:58:36 2022 +0000
tree 4eff7f90f9ca2376260fd5949821a9659c32c6d6
parent a09e67800bf217ac4cc5b4f69474ac0421496e9a

SurfaceFlinger: add logging when changing refresh rate policy

Add a log message when refresh rate policy is changed to help
debug issues when SF changes refresh rate unexpectedly.

Bug: 230590870
Test: change policy over adb and observe logs
Change-Id: I31cdc3ad47ea25c0f700ebad897e7efbc986bd24

services/surfaceflinger/DisplayDevice.cpp

diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index a915b61..8680900 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -211,6 +211,7 @@
               to_string(getId()).c_str());
         return BAD_VALUE;
     }
+    mNumModeSwitchesInPolicy++;
     mUpcomingActiveMode = info;
     ATRACE_INT(mActiveModeFPSHwcTrace.c_str(), info.mode->getFps().getIntValue());
     return mHwComposer.setActiveModeWithConstraints(getPhysicalId(), info.mode->getHwcId(),
@@ -537,6 +538,27 @@
     mDesiredActiveModeChanged = false;
 }
 
+status_t DisplayDevice::setRefreshRatePolicy(
+        const std::optional<scheduler::RefreshRateConfigs::Policy>& policy, bool overridePolicy) {
+    const auto oldPolicy = mRefreshRateConfigs->getCurrentPolicy();
+    const status_t setPolicyResult = overridePolicy
+            ? mRefreshRateConfigs->setOverridePolicy(policy)
+            : mRefreshRateConfigs->setDisplayManagerPolicy(*policy);
+
+    if (setPolicyResult == OK) {
+        const int numModeChanges = mNumModeSwitchesInPolicy.exchange(0);
+
+        ALOGI("Display %s policy changed\n"
+              "Previous: {%s}\n"
+              "Current:  {%s}\n"
+              "%d mode changes were performed under the previous policy",
+              to_string(getId()).c_str(), oldPolicy.toString().c_str(),
+              policy ? policy->toString().c_str() : "null", numModeChanges);
+    }
+
+    return setPolicyResult;
+}
+
 std::atomic<int32_t> DisplayDeviceState::sNextSequenceId(1);
 
 }  // namespace android

services/surfaceflinger/DisplayDevice.h

diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index d5d87b4..2161436 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -249,6 +249,10 @@
     nsecs_t getVsyncPeriodFromHWC() const;
     nsecs_t getRefreshTimestamp() const;
 
+    status_t setRefreshRatePolicy(
+            const std::optional<scheduler::RefreshRateConfigs::Policy>& policy,
+            bool overridePolicy);
+
     // release HWC resources (if any) for removable displays
     void disconnect();
 
@@ -303,6 +307,8 @@
     TracedOrdinal<bool> mDesiredActiveModeChanged
             GUARDED_BY(mActiveModeLock) = {"DesiredActiveModeChanged", false};
     ActiveModeInfo mUpcomingActiveMode GUARDED_BY(kMainThreadContext);
+
+    std::atomic_int mNumModeSwitchesInPolicy = 0;
 };
 
 struct DisplayDeviceState {

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 5cf9558..2cd9e1e 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -6913,9 +6913,7 @@
         return NO_ERROR;
     }
 
-    status_t setPolicyResult = overridePolicy
-            ? display->refreshRateConfigs().setOverridePolicy(policy)
-            : display->refreshRateConfigs().setDisplayManagerPolicy(*policy);
+    const status_t setPolicyResult = display->setRefreshRatePolicy(policy, overridePolicy);
     if (setPolicyResult < 0) {
         return BAD_VALUE;
     }