Remove legacy memory trim code

Modern trim is here to stay.

Bug: 253914117
Bug: 329427668

Change-Id: I24c0c7a6ae7452cf8b5989e8997e549e312b370f

5 files changed, 32 insertions, 131 deletions

diff --git a/services/core/java/com/android/server/am/ActivityManagerConstants.java b/services/core/java/com/android/server/am/ActivityManagerConstants.java
index 272e84b80870..f7ed702f1044 100644
--- a/services/core/java/com/android/server/am/ActivityManagerConstants.java
+++ b/services/core/java/com/android/server/am/ActivityManagerConstants.java
@@ -163,7 +163,6 @@ final class ActivityManagerConstants extends ContentObserver {
 
     static final String KEY_USE_TIERED_CACHED_ADJ = "use_tiered_cached_adj";
     static final String KEY_TIERED_CACHED_ADJ_DECAY_TIME = "tiered_cached_adj_decay_time";
-    static final String KEY_USE_MODERN_TRIM = "use_modern_trim";
 
     /**
      * Whether or not to enable the new oom adjuster implementation.
@@ -239,8 +238,6 @@ final class ActivityManagerConstants extends ContentObserver {
     private static final boolean DEFAULT_USE_TIERED_CACHED_ADJ = false;
     private static final long DEFAULT_TIERED_CACHED_ADJ_DECAY_TIME = 60 * 1000;
 
-    private static final boolean DEFAULT_USE_MODERN_TRIM = true;
-
     /**
      * The default value to {@link #KEY_ENABLE_NEW_OOMADJ}.
      */
@@ -1136,9 +1133,6 @@ final class ActivityManagerConstants extends ContentObserver {
     /** @see #KEY_TIERED_CACHED_ADJ_DECAY_TIME */
     public long TIERED_CACHED_ADJ_DECAY_TIME = DEFAULT_TIERED_CACHED_ADJ_DECAY_TIME;
 
-    /** @see #KEY_USE_MODERN_TRIM */
-    public boolean USE_MODERN_TRIM = DEFAULT_USE_MODERN_TRIM;
-
     /** @see #KEY_ENABLE_NEW_OOMADJ */
     public boolean ENABLE_NEW_OOMADJ = DEFAULT_ENABLE_NEW_OOM_ADJ;
 
@@ -1343,9 +1337,6 @@ final class ActivityManagerConstants extends ContentObserver {
                             case KEY_TIERED_CACHED_ADJ_DECAY_TIME:
                                 updateUseTieredCachedAdj();
                                 break;
-                            case KEY_USE_MODERN_TRIM:
-                                updateUseModernTrim();
-                                break;
                             case KEY_DISABLE_APP_PROFILER_PSS_PROFILING:
                                 updateDisableAppProfilerPssProfiling();
                                 break;
@@ -2233,13 +2224,6 @@ final class ActivityManagerConstants extends ContentObserver {
             DEFAULT_TIERED_CACHED_ADJ_DECAY_TIME);
     }
 
-    private void updateUseModernTrim() {
-        USE_MODERN_TRIM = DeviceConfig.getBoolean(
-            DeviceConfig.NAMESPACE_ACTIVITY_MANAGER,
-            KEY_USE_MODERN_TRIM,
-            DEFAULT_USE_MODERN_TRIM);
-    }
-
     private void updateEnableNewOomAdj() {
         ENABLE_NEW_OOMADJ = DeviceConfig.getBoolean(
             DeviceConfig.NAMESPACE_ACTIVITY_MANAGER_NATIVE_BOOT,
diff --git a/services/core/java/com/android/server/am/AppProfiler.java b/services/core/java/com/android/server/am/AppProfiler.java
index 48daef801245..51aae771542e 100644
--- a/services/core/java/com/android/server/am/AppProfiler.java
+++ b/services/core/java/com/android/server/am/AppProfiler.java
@@ -1357,7 +1357,7 @@ public class AppProfiler {
     }
 
     @GuardedBy({"mService", "mProcLock"})
-    boolean updateLowMemStateLSP(int numCached, int numEmpty, int numTrimming, long now) {
+    void updateLowMemStateLSP(int numCached, int numEmpty, int numTrimming, long now) {
         int memFactor;
         if (mLowMemDetector != null && mLowMemDetector.isAvailable()) {
             memFactor = mLowMemDetector.getMemFactor();
@@ -1422,114 +1422,37 @@ public class AppProfiler {
 
         mLastMemoryLevel = memFactor;
         mLastNumProcesses = mService.mProcessList.getLruSizeLOSP();
-        if (mService.mConstants.USE_MODERN_TRIM) {
-            // Modern trim is not sent based on lowmem state
-            // Dispatch UI_HIDDEN to processes that need it
-            mService.mProcessList.forEachLruProcessesLOSP(true, app -> {
-                final ProcessProfileRecord profile = app.mProfile;
-                final IApplicationThread thread;
-                final ProcessStateRecord state = app.mState;
-                if (state.hasProcStateChanged()) {
-                    state.setProcStateChanged(false);
-                }
-                int procState = app.mState.getCurProcState();
-                if (((procState >= ActivityManager.PROCESS_STATE_IMPORTANT_BACKGROUND
-                        && procState < ActivityManager.PROCESS_STATE_CACHED_ACTIVITY)
-                        || app.mState.isSystemNoUi()) && app.mProfile.hasPendingUiClean()) {
-                    // If this application is now in the background and it
-                    // had done UI, then give it the special trim level to
-                    // have it free UI resources.
-                    if ((thread = app.getThread()) != null) {
-                        try {
-                            thread.scheduleTrimMemory(ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN);
-                            app.mProfile.setPendingUiClean(false);
-                        } catch (RemoteException e) {
 
-                        }
+        // Dispatch UI_HIDDEN to processes that need it
+        mService.mProcessList.forEachLruProcessesLOSP(
+                true,
+                app -> {
+                    final ProcessProfileRecord profile = app.mProfile;
+                    final IApplicationThread thread;
+                    final ProcessStateRecord state = app.mState;
+                    if (state.hasProcStateChanged()) {
+                        state.setProcStateChanged(false);
                     }
-                }
-            });
-            return false;
-        }
+                    int procState = app.mState.getCurProcState();
+                    if (((procState >= ActivityManager.PROCESS_STATE_IMPORTANT_BACKGROUND
+                                            && procState
+                                                    < ActivityManager.PROCESS_STATE_CACHED_ACTIVITY)
+                                    || app.mState.isSystemNoUi())
+                            && app.mProfile.hasPendingUiClean()) {
+                        // If this application is now in the background and it
+                        // had done UI, then give it the special trim level to
+                        // have it free UI resources.
+                        if ((thread = app.getThread()) != null) {
+                            try {
+                                thread.scheduleTrimMemory(
+                                        ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN);
+                                app.mProfile.setPendingUiClean(false);
+                            } catch (RemoteException e) {
 
-        if (memFactor != ADJ_MEM_FACTOR_NORMAL) {
-            if (mLowRamStartTime == 0) {
-                mLowRamStartTime = now;
-            }
-            int fgTrimLevel;
-            switch (memFactor) {
-                case ADJ_MEM_FACTOR_CRITICAL:
-                    fgTrimLevel = ComponentCallbacks2.TRIM_MEMORY_RUNNING_CRITICAL;
-                    break;
-                case ADJ_MEM_FACTOR_LOW:
-                    fgTrimLevel = ComponentCallbacks2.TRIM_MEMORY_RUNNING_LOW;
-                    break;
-                default:
-                    fgTrimLevel = ComponentCallbacks2.TRIM_MEMORY_RUNNING_MODERATE;
-                    break;
-            }
-            int factor = numTrimming / 3;
-            int minFactor = 2;
-            if (mHasHomeProcess) minFactor++;
-            if (mHasPreviousProcess) minFactor++;
-            if (factor < minFactor) factor = minFactor;
-            final int actualFactor = factor;
-            final int[] step = {0};
-            final int[] curLevel = {ComponentCallbacks2.TRIM_MEMORY_COMPLETE};
-            mService.mProcessList.forEachLruProcessesLOSP(true, app -> {
-                final ProcessProfileRecord profile = app.mProfile;
-                final int trimMemoryLevel = profile.getTrimMemoryLevel();
-                final ProcessStateRecord state = app.mState;
-                final int curProcState = state.getCurProcState();
-                IApplicationThread thread;
-                if (allChanged || state.hasProcStateChanged()) {
-                    mService.setProcessTrackerStateLOSP(app, trackerMemFactor);
-                    state.setProcStateChanged(false);
-                }
-                trimMemoryUiHiddenIfNecessaryLSP(app);
-                if (curProcState >= ActivityManager.PROCESS_STATE_HOME && !app.isKilledByAm()) {
-                    scheduleTrimMemoryLSP(app, curLevel[0], "Trimming memory of ");
-                    profile.setTrimMemoryLevel(curLevel[0]);
-                    step[0]++;
-                    if (step[0] >= actualFactor) {
-                        step[0] = 0;
-                        switch (curLevel[0]) {
-                            case ComponentCallbacks2.TRIM_MEMORY_COMPLETE:
-                                curLevel[0] = ComponentCallbacks2.TRIM_MEMORY_MODERATE;
-                                break;
-                            case ComponentCallbacks2.TRIM_MEMORY_MODERATE:
-                                curLevel[0] = ComponentCallbacks2.TRIM_MEMORY_BACKGROUND;
-                                break;
+                            }
                         }
                     }
-                } else if (curProcState == ActivityManager.PROCESS_STATE_HEAVY_WEIGHT
-                        && !app.isKilledByAm()) {
-                    scheduleTrimMemoryLSP(app, ComponentCallbacks2.TRIM_MEMORY_BACKGROUND,
-                            "Trimming memory of heavy-weight ");
-                    profile.setTrimMemoryLevel(ComponentCallbacks2.TRIM_MEMORY_BACKGROUND);
-                } else {
-                    scheduleTrimMemoryLSP(app, fgTrimLevel, "Trimming memory of fg ");
-                    profile.setTrimMemoryLevel(fgTrimLevel);
-                }
-            });
-        } else {
-            if (mLowRamStartTime != 0) {
-                mLowRamTimeSinceLastIdle += now - mLowRamStartTime;
-                mLowRamStartTime = 0;
-            }
-            mService.mProcessList.forEachLruProcessesLOSP(true, app -> {
-                final ProcessProfileRecord profile = app.mProfile;
-                final IApplicationThread thread;
-                final ProcessStateRecord state = app.mState;
-                if (allChanged || state.hasProcStateChanged()) {
-                    mService.setProcessTrackerStateLOSP(app, trackerMemFactor);
-                    state.setProcStateChanged(false);
-                }
-                trimMemoryUiHiddenIfNecessaryLSP(app);
-                profile.setTrimMemoryLevel(0);
-            });
-        }
-        return allChanged;
+                });
     }
 
     @GuardedBy({"mService", "mProcLock"})
diff --git a/services/core/java/com/android/server/am/CachedAppOptimizer.java b/services/core/java/com/android/server/am/CachedAppOptimizer.java
index 6e20f6cc877d..de27bc708ffd 100644
--- a/services/core/java/com/android/server/am/CachedAppOptimizer.java
+++ b/services/core/java/com/android/server/am/CachedAppOptimizer.java
@@ -1461,8 +1461,7 @@ public final class CachedAppOptimizer {
             return;
         }
 
-        if (mAm.mConstants.USE_MODERN_TRIM
-                && app.mState.getSetAdj() >= ProcessList.CACHED_APP_MIN_ADJ) {
+        if (app.mState.getSetAdj() >= ProcessList.CACHED_APP_MIN_ADJ) {
             final IApplicationThread thread = app.getThread();
             if (thread != null) {
                 try {
diff --git a/services/core/java/com/android/server/am/OomAdjuster.java b/services/core/java/com/android/server/am/OomAdjuster.java
index 1a7629f3182d..5e91cd39b698 100644
--- a/services/core/java/com/android/server/am/OomAdjuster.java
+++ b/services/core/java/com/android/server/am/OomAdjuster.java
@@ -1090,7 +1090,7 @@ public class OomAdjuster {
         mNumNonCachedProcs = 0;
         mNumCachedHiddenProcs = 0;
 
-        final boolean allChanged = updateAndTrimProcessLSP(now, nowElapsed, oldTime, activeUids,
+        updateAndTrimProcessLSP(now, nowElapsed, oldTime, activeUids,
                 oomAdjReason, doingAll);
         mNumServiceProcs = mNewNumServiceProcs;
 
@@ -1100,11 +1100,6 @@ public class OomAdjuster {
             mService.mAtmInternal.scheduleDestroyAllActivities("always-finish");
         }
 
-        if (allChanged) {
-            mService.mAppProfiler.requestPssAllProcsLPr(now, false,
-                    mService.mProcessStats.isMemFactorLowered());
-        }
-
         updateUidsLSP(activeUids, nowElapsed);
 
         synchronized (mService.mProcessStats.mLock) {
@@ -1300,7 +1295,7 @@ public class OomAdjuster {
     }
 
     @GuardedBy({"mService", "mProcLock"})
-    private boolean updateAndTrimProcessLSP(final long now, final long nowElapsed,
+    private void updateAndTrimProcessLSP(final long now, final long nowElapsed,
             final long oldTime, final ActiveUids activeUids, @OomAdjReason int oomAdjReason,
             boolean doingAll) {
         ArrayList<ProcessRecord> lruList = mProcessList.getLruProcessesLOSP();
@@ -1450,7 +1445,7 @@ public class OomAdjuster {
 
         mLastFreeSwapPercent = freeSwapPercent;
 
-        return mService.mAppProfiler.updateLowMemStateLSP(numCached, numEmpty, numTrimming, now);
+        mService.mAppProfiler.updateLowMemStateLSP(numCached, numEmpty, numTrimming, now);
     }
 
     @GuardedBy({"mService", "mProcLock"})
diff --git a/services/tests/mockingservicestests/src/com/android/server/am/ServiceBindingOomAdjPolicyTest.java b/services/tests/mockingservicestests/src/com/android/server/am/ServiceBindingOomAdjPolicyTest.java
index 680ab1634cb2..daa827eacf44 100644
--- a/services/tests/mockingservicestests/src/com/android/server/am/ServiceBindingOomAdjPolicyTest.java
+++ b/services/tests/mockingservicestests/src/com/android/server/am/ServiceBindingOomAdjPolicyTest.java
@@ -186,7 +186,7 @@ public final class ServiceBindingOomAdjPolicyTest {
         doReturn(true).when(mAms.mOomAdjuster.mCachedAppOptimizer).useFreezer();
         doNothing().when(mAms.mOomAdjuster.mCachedAppOptimizer).freezeAppAsyncAtEarliestLSP(
                 any());
-        doReturn(false).when(mAms.mAppProfiler).updateLowMemStateLSP(anyInt(), anyInt(),
+        doNothing().when(mAms.mAppProfiler).updateLowMemStateLSP(anyInt(), anyInt(),
                 anyInt(), anyLong());
 
         mCurrentCallingUid = TEST_APP1_UID;