Merge "Introduce a way to debug relayouts and slow measures/layout" into tm-qpr-dev am: c261087167

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21040074

Change-Id: I9ec6fd5d933f0e2f60f61b890396d251ee5d6e1d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

core/java/android/os/Trace.java

@@ -110,7 +110,8 @@ public final class Trace {
     public static final long TRACE_TAG_THERMAL = 1L << 27;
 
     private static final long TRACE_TAG_NOT_READY = 1L << 63;
-    private static final int MAX_SECTION_NAME_LEN = 127;
+    /** @hide **/
+    public static final int MAX_SECTION_NAME_LEN = 127;
 
     // Must be volatile to avoid word tearing.
     // This is only kept in case any apps get this by reflection but do not

core/java/android/view/View.java

@@ -17,6 +17,7 @@
 package android.view;
 
 import static android.content.res.Resources.ID_NULL;
+import static android.os.Trace.TRACE_TAG_APP;
 import static android.view.ContentInfo.SOURCE_DRAG_AND_DROP;
 import static android.view.accessibility.AccessibilityEvent.CONTENT_CHANGE_TYPE_UNDEFINED;
 import static android.view.displayhash.DisplayHashResultCallback.DISPLAY_HASH_ERROR_INVALID_BOUNDS;
@@ -984,6 +985,22 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
      */
     private static boolean sAcceptZeroSizeDragShadow;
 
+    /**
+     * When true, measure and layout passes of all the newly attached views will be logged with
+     * {@link Trace}, so we can better debug jank due to complex view hierarchies.
+     */
+    private static boolean sTraceLayoutSteps;
+
+    /**
+     * When not null, emits a {@link Trace} instant event and the stacktrace every time a relayout
+     * of a class having this name happens.
+     */
+    private static String sTraceRequestLayoutClass;
+
+    /** Used to avoid computing the full strings each time when layout tracing is enabled. */
+    @Nullable
+    private ViewTraversalTracingStrings mTracingStrings;
+
     /**
      * Prior to R, {@link #dispatchApplyWindowInsets} had an issue:
      * <p>The modified insets changed by {@link #onApplyWindowInsets} were passed to the
@@ -3532,6 +3549,8 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
      *                  1               PFLAG4_HAS_TRANSLATION_TRANSIENT_STATE
      *                 1                PFLAG4_DRAG_A11Y_STARTED
      *                1                 PFLAG4_AUTO_HANDWRITING_INITIATION_ENABLED
+     *             1                    PFLAG4_TRAVERSAL_TRACING_ENABLED
+     *            1                     PFLAG4_RELAYOUT_TRACING_ENABLED
      * |-------|-------|-------|-------|
      */
 
@@ -3612,6 +3631,19 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
      * Indicates that the view enables auto handwriting initiation.
      */
     private static final int PFLAG4_AUTO_HANDWRITING_ENABLED = 0x000010000;
+
+    /**
+     * When set, measure and layout passes of this view will be logged with {@link Trace}, so we
+     * can better debug jank due to complex view hierarchies.
+     */
+    private static final int PFLAG4_TRAVERSAL_TRACING_ENABLED = 0x000040000;
+
+    /**
+     * When set, emits a {@link Trace} instant event and stacktrace every time a requestLayout of
+     * this class happens.
+     */
+    private static final int PFLAG4_RELAYOUT_TRACING_ENABLED = 0x000080000;
+
     /* End of masks for mPrivateFlags4 */
 
     /** @hide */
@@ -6537,6 +6569,15 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
         out.append(mRight);
         out.append(',');
         out.append(mBottom);
+        appendId(out);
+        if (mAutofillId != null) {
+            out.append(" aid="); out.append(mAutofillId);
+        }
+        out.append("}");
+        return out.toString();
+    }
+
+    void appendId(StringBuilder out) {
         final int id = getId();
         if (id != NO_ID) {
             out.append(" #");
@@ -6568,11 +6609,6 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
                 }
             }
         }
-        if (mAutofillId != null) {
-            out.append(" aid="); out.append(mAutofillId);
-        }
-        out.append("}");
-        return out.toString();
     }
 
     /**
@@ -20771,6 +20807,14 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
         if (isFocused()) {
             notifyFocusChangeToImeFocusController(true /* hasFocus */);
         }
+
+        if (sTraceLayoutSteps) {
+            setTraversalTracingEnabled(true);
+        }
+        if (sTraceRequestLayoutClass != null
+                && sTraceRequestLayoutClass.equals(getClass().getSimpleName())) {
+            setRelayoutTracingEnabled(true);
+        }
     }
 
     /**
@@ -23670,6 +23714,30 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
         return o instanceof ViewGroup && ((ViewGroup) o).isLayoutModeOptical();
     }
 
+    /**
+     * Enable measure/layout debugging on traces.
+     *
+     * @see Trace
+     * @hide
+     */
+    public static void setTraceLayoutSteps(boolean traceLayoutSteps) {
+        sTraceLayoutSteps = traceLayoutSteps;
+    }
+
+    /**
+     * Enable request layout tracing classes with {@code s} simple name.
+     * <p>
+     * When set, a {@link Trace} instant event and a log with the stacktrace is emitted every
+     * time a requestLayout of a class matching {@code s} name happens.
+     * This applies only to views attached from this point onwards.
+     *
+     * @see Trace#instant(long, String)
+     * @hide
+     */
+    public static void setTracedRequestLayoutClassClass(String s) {
+        sTraceRequestLayoutClass = s;
+    }
+
     private boolean setOpticalFrame(int left, int top, int right, int bottom) {
         Insets parentInsets = mParent instanceof View ?
                 ((View) mParent).getOpticalInsets() : Insets.NONE;
@@ -23704,7 +23772,13 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
     @SuppressWarnings({"unchecked"})
     public void layout(int l, int t, int r, int b) {
         if ((mPrivateFlags3 & PFLAG3_MEASURE_NEEDED_BEFORE_LAYOUT) != 0) {
+            if (isTraversalTracingEnabled()) {
+                Trace.beginSection(mTracingStrings.onMeasureBeforeLayout);
+            }
             onMeasure(mOldWidthMeasureSpec, mOldHeightMeasureSpec);
+            if (isTraversalTracingEnabled()) {
+                Trace.endSection();
+            }
             mPrivateFlags3 &= ~PFLAG3_MEASURE_NEEDED_BEFORE_LAYOUT;
         }
 
@@ -23717,7 +23791,13 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
                 setOpticalFrame(l, t, r, b) : setFrame(l, t, r, b);
 
         if (changed || (mPrivateFlags & PFLAG_LAYOUT_REQUIRED) == PFLAG_LAYOUT_REQUIRED) {
+            if (isTraversalTracingEnabled()) {
+                Trace.beginSection(mTracingStrings.onLayout);
+            }
             onLayout(changed, l, t, r, b);
+            if (isTraversalTracingEnabled()) {
+                Trace.endSection();
+            }
 
             if (shouldDrawRoundScrollbar()) {
                 if(mRoundScrollbarRenderer == null) {
@@ -26274,6 +26354,25 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
         return (viewRoot != null && viewRoot.isInLayout());
     }
 
+    /** To be used only for debugging purposes. */
+    private void printStackStrace(String name) {
+        Log.d(VIEW_LOG_TAG, "---- ST:" + name);
+
+        StringBuilder sb = new StringBuilder();
+        StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
+        int startIndex = 1;
+        int endIndex = Math.min(stackTraceElements.length, startIndex + 20); // max 20 entries.
+        for (int i = startIndex; i < endIndex; i++) {
+            StackTraceElement s = stackTraceElements[i];
+            sb.append(s.getMethodName())
+                    .append("(")
+                    .append(s.getFileName())
+                    .append(":")
+                    .append(s.getLineNumber())
+                    .append(") <- ");
+        }
+        Log.d(VIEW_LOG_TAG, name + ": " + sb);
+    }
     /**
      * Call this when something has changed which has invalidated the
      * layout of this view. This will schedule a layout pass of the view
@@ -26287,6 +26386,12 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
      */
     @CallSuper
     public void requestLayout() {
+        if (isRelayoutTracingEnabled()) {
+            Trace.instantForTrack(TRACE_TAG_APP, "requestLayoutTracing",
+                    mTracingStrings.classSimpleName);
+            printStackStrace(mTracingStrings.requestLayoutStacktracePrefix);
+        }
+
         if (mMeasureCache != null) mMeasureCache.clear();
 
         if (mAttachInfo != null && mAttachInfo.mViewRequestingLayout == null) {
@@ -26380,8 +26485,14 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
 
             int cacheIndex = forceLayout ? -1 : mMeasureCache.indexOfKey(key);
             if (cacheIndex < 0 || sIgnoreMeasureCache) {
+                if (isTraversalTracingEnabled()) {
+                    Trace.beginSection(mTracingStrings.onMeasure);
+                }
                 // measure ourselves, this should set the measured dimension flag back
                 onMeasure(widthMeasureSpec, heightMeasureSpec);
+                if (isTraversalTracingEnabled()) {
+                    Trace.endSection();
+                }
                 mPrivateFlags3 &= ~PFLAG3_MEASURE_NEEDED_BEFORE_LAYOUT;
             } else {
                 long value = mMeasureCache.valueAt(cacheIndex);
@@ -31551,6 +31662,38 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
                 == PFLAG4_AUTO_HANDWRITING_ENABLED;
     }
 
+    private void setTraversalTracingEnabled(boolean enabled) {
+        if (enabled) {
+            if (mTracingStrings == null) {
+                mTracingStrings = new ViewTraversalTracingStrings(this);
+            }
+            mPrivateFlags4 |= PFLAG4_TRAVERSAL_TRACING_ENABLED;
+        } else {
+            mPrivateFlags4 &= ~PFLAG4_TRAVERSAL_TRACING_ENABLED;
+        }
+    }
+
+    private boolean isTraversalTracingEnabled() {
+        return (mPrivateFlags4 & PFLAG4_TRAVERSAL_TRACING_ENABLED)
+                == PFLAG4_TRAVERSAL_TRACING_ENABLED;
+    }
+
+    private void setRelayoutTracingEnabled(boolean enabled) {
+        if (enabled) {
+            if (mTracingStrings == null) {
+                mTracingStrings = new ViewTraversalTracingStrings(this);
+            }
+            mPrivateFlags4 |= PFLAG4_RELAYOUT_TRACING_ENABLED;
+        } else {
+            mPrivateFlags4 &= ~PFLAG4_RELAYOUT_TRACING_ENABLED;
+        }
+    }
+
+    private boolean isRelayoutTracingEnabled() {
+        return (mPrivateFlags4 & PFLAG4_RELAYOUT_TRACING_ENABLED)
+                == PFLAG4_RELAYOUT_TRACING_ENABLED;
+    }
+
     /**
      * Collects a {@link ViewTranslationRequest} which represents the content to be translated in
      * the view.

core/java/android/view/ViewTraversalTracingStrings.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view;
+
+import android.os.Trace;
+
+/**
+ * Keeps and caches strings used to trace {@link View} traversals.
+ * <p>
+ * This is done to avoid expensive computations of them every time, which can improve performance.
+ */
+class ViewTraversalTracingStrings {
+
+    /** {@link Trace} tag used to mark {@link View#onMeasure(int, int)}. */
+    public final String onMeasure;
+
+    /** {@link Trace} tag used to mark {@link View#onLayout(boolean, int, int, int, int)}. */
+    public final String onLayout;
+
+    /** Caches the view simple name to avoid re-computations. */
+    public final String classSimpleName;
+
+    /** Prefix for request layout stacktraces output in logs. */
+    public final String requestLayoutStacktracePrefix;
+
+    /** {@link Trace} tag used to mark {@link View#onMeasure(int, int)} happening before layout. */
+    public final String onMeasureBeforeLayout;
+
+    /**
+     * @param v {@link View} from where to get the class name.
+     */
+    ViewTraversalTracingStrings(View v) {
+        String className = v.getClass().getSimpleName();
+        classSimpleName = className;
+        onMeasureBeforeLayout = getTraceName("onMeasureBeforeLayout", className, v);
+        onMeasure = getTraceName("onMeasure", className, v);
+        onLayout = getTraceName("onLayout", className, v);
+        requestLayoutStacktracePrefix = "requestLayout " + className;
+    }
+
+    private String getTraceName(String sectionName, String className, View v) {
+        StringBuilder out = new StringBuilder();
+        out.append(sectionName);
+        out.append(" ");
+        out.append(className);
+        v.appendId(out);
+        return out.substring(0, Math.min(out.length() - 1, Trace.MAX_SECTION_NAME_LEN - 1));
+    }
+}

packages/SystemUI/src/com/android/systemui/SystemUIApplication.java

@@ -38,6 +38,7 @@ import android.util.Log;
 import android.util.TimingsTraceLog;
 import android.view.SurfaceControl;
 import android.view.ThreadedRenderer;
+import android.view.View;
 
 import com.android.internal.protolog.common.ProtoLog;
 import com.android.systemui.dagger.GlobalRootComponent;
@@ -112,6 +113,11 @@ public class SystemUIApplication extends Application implements
         // the theme set there.
         setTheme(R.style.Theme_SystemUI);
 
+        View.setTraceLayoutSteps(
+                SystemProperties.getBoolean("persist.debug.trace_layouts", false));
+        View.setTracedRequestLayoutClassClass(
+                SystemProperties.get("persist.debug.trace_request_layout_class", null));
+
         if (Process.myUserHandle().equals(UserHandle.SYSTEM)) {
             IntentFilter bootCompletedFilter = new
                     IntentFilter(Intent.ACTION_LOCKED_BOOT_COMPLETED);