From ddd1be66884320f834f650ac815bc2140b3cb174 Mon Sep 17 00:00:00 2001
From: Tim Murray <timmurray@google.com>
Date: Mon, 3 Oct 2022 10:14:15 -0700
Subject: [PATCH] display: fix trace spam

requestDisplayStateInternal was creating too many async
tracks. Convert to asyncTraceForTrack to make traces comprehensible.

Test: traces appear
Bug: 250614152
Change-Id: Icc921f0a12a1a89a10280477c10374f19c8af4ef
---
 .../server/display/DisplayManagerService.java | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/services/core/java/com/android/server/display/DisplayManagerService.java b/services/core/java/com/android/server/display/DisplayManagerService.java
index e851f03c92ef7..84891c7c74a39 100644
--- a/services/core/java/com/android/server/display/DisplayManagerService.java
+++ b/services/core/java/com/android/server/display/DisplayManagerService.java
@@ -775,18 +775,24 @@ public final class DisplayManagerService extends SystemService {
                 return; // Display no longer exists or no change.
             }
 
-            traceMessage = "requestDisplayStateInternal("
-                    + displayId + ", "
-                    + Display.stateToString(state)
-                    + ", brightness=" + brightnessState
-                    + ", sdrBrightness=" + sdrBrightnessState + ")";
-            Trace.asyncTraceBegin(Trace.TRACE_TAG_POWER, traceMessage, displayId);
+            if (Trace.isTagEnabled(Trace.TRACE_TAG_POWER)) {
+                traceMessage = Display.stateToString(state)
+                           + ", brightness=" + brightnessState
+                           + ", sdrBrightness=" + sdrBrightnessState;
+                Trace.asyncTraceForTrackBegin(Trace.TRACE_TAG_POWER,
+                        "requestDisplayStateInternal:" + displayId,
+                        traceMessage, displayId);
+            }
 
             mDisplayStates.setValueAt(index, state);
             brightnessPair.brightness = brightnessState;
             brightnessPair.sdrBrightness = sdrBrightnessState;
             runnable = updateDisplayStateLocked(mLogicalDisplayMapper.getDisplayLocked(displayId)
                     .getPrimaryDisplayDeviceLocked());
+            if (Trace.isTagEnabled(Trace.TRACE_TAG_POWER)) {
+                Trace.asyncTraceForTrackEnd(Trace.TRACE_TAG_POWER,
+                        "requestDisplayStateInternal:" + displayId, displayId);
+            }
         }
 
         // Setting the display power state can take hundreds of milliseconds
@@ -796,7 +802,6 @@ public final class DisplayManagerService extends SystemService {
         if (runnable != null) {
             runnable.run();
         }
-        Trace.asyncTraceEnd(Trace.TRACE_TAG_POWER, traceMessage, displayId);
     }
 
     private class SettingsObserver extends ContentObserver {