Implement CarStorageMonitoringManager::getIoStatsDeltas

This API gives access to the periodic snapshot deltas of I/O activity calculated by CarStorageMonitoringService

Bug: 32512551
Bug: 65846699
Test: bit CarServiceTest:com.android.car.CarStorageMonitoringTest
      bit CarServiceUnitTest:com.android.car.storagemonitoring.CarStorageMonitoringTest

Change-Id: I833d4b4d0e63d6356b34584dbde3ba563e4aa899

6 files changed, 266 insertions, 35 deletions

diff --git a/car-lib/src/android/car/storagemonitoring/CarStorageMonitoringManager.java b/car-lib/src/android/car/storagemonitoring/CarStorageMonitoringManager.java
index 51d77d106c..cc32acc2ba 100644
--- a/car-lib/src/android/car/storagemonitoring/CarStorageMonitoringManager.java
+++ b/car-lib/src/android/car/storagemonitoring/CarStorageMonitoringManager.java
@@ -162,4 +162,26 @@ public final class CarStorageMonitoringManager implements CarManagerBase {
         return Collections.emptyList();
     }
 
+    /**
+     * This method returns a list of the I/O stats deltas currently stored by the system.
+     *
+     * Periodically, the system gathers I/O activity metrics and computes and stores a delta from
+     * the previous cycle. The timing and the number of these stored samples are configurable
+     * by the OEM.
+     *
+     * The samples are returned in order from the oldest to the newest.
+     *
+     * If the information is not available, an empty list will be returned.
+     */
+    @RequiresPermission(value=Car.PERMISSION_STORAGE_MONITORING)
+    public List<UidIoStatsDelta> getIoStatsDeltas() throws CarNotConnectedException {
+        try {
+            return mService.getIoStatsDeltas();
+        } catch (IllegalStateException e) {
+            checkCarNotConnectedExceptionFromCarService(e);
+        } catch (RemoteException e) {
+            throw new CarNotConnectedException();
+        }
+        return Collections.emptyList();
+    }
 }
diff --git a/car-lib/src/android/car/storagemonitoring/ICarStorageMonitoring.aidl b/car-lib/src/android/car/storagemonitoring/ICarStorageMonitoring.aidl
index cedb3433f2..d8183d6628 100644
--- a/car-lib/src/android/car/storagemonitoring/ICarStorageMonitoring.aidl
+++ b/car-lib/src/android/car/storagemonitoring/ICarStorageMonitoring.aidl
@@ -17,6 +17,7 @@
 package android.car.storagemonitoring;
 
 import android.car.storagemonitoring.UidIoStats;
+import android.car.storagemonitoring.UidIoStatsDelta;
 import android.car.storagemonitoring.WearEstimate;
 import android.car.storagemonitoring.WearEstimateChange;
 
@@ -47,4 +48,8 @@ interface ICarStorageMonitoring {
    */
   List<UidIoStats> getAggregateIoStats() = 5;
 
+  /**
+   * Return the I/O stats deltas currently known to the service.
+   */
+  List<UidIoStatsDelta> getIoStatsDeltas() = 6;
 }
diff --git a/car-lib/src/android/car/storagemonitoring/UidIoStatsRecord.java b/car-lib/src/android/car/storagemonitoring/UidIoRecord.java
index abd9ee04be..196c83ce05 100644
--- a/car-lib/src/android/car/storagemonitoring/UidIoStatsRecord.java
+++ b/car-lib/src/android/car/storagemonitoring/UidIoRecord.java
@@ -23,7 +23,7 @@ import android.annotation.SystemApi;
  * @hide
  */
 @SystemApi
-public final class UidIoStatsRecord {
+public final class UidIoRecord {
 
     public final int uid;
 
@@ -39,7 +39,7 @@ public final class UidIoStatsRecord {
     public final long background_write_bytes;
     public final long background_fsync;
 
-    public UidIoStatsRecord(int uid,
+    public UidIoRecord(int uid,
             long foreground_rchar,
             long foreground_wchar,
             long foreground_read_bytes,
@@ -66,12 +66,12 @@ public final class UidIoStatsRecord {
     }
 
     /** @hide */
-    public UidIoStatsRecord delta(UidIoStats other) {
+    public UidIoRecord delta(UidIoStats other) {
         if (uid != other.uid) {
             throw new IllegalArgumentException("cannot calculate delta between different user IDs");
         }
 
-        return new UidIoStatsRecord(uid,
+        return new UidIoRecord(uid,
             foreground_rchar - other.foreground.bytesRead,
             foreground_wchar - other.foreground.bytesWritten,
             foreground_read_bytes - other.foreground.bytesReadFromStorage,
@@ -83,4 +83,23 @@ public final class UidIoStatsRecord {
             background_write_bytes - other.background.bytesWrittenToStorage,
             background_fsync - other.background.fsyncCalls);
     }
+
+    /** @hide */
+    public UidIoRecord delta(UidIoRecord other) {
+        if (uid != other.uid) {
+            throw new IllegalArgumentException("cannot calculate delta between different user IDs");
+        }
+
+        return new UidIoRecord(uid,
+            foreground_rchar - other.foreground_rchar,
+            foreground_wchar - other.foreground_wchar,
+            foreground_read_bytes - other.foreground_read_bytes,
+            foreground_write_bytes - other.foreground_write_bytes,
+            foreground_fsync - other.foreground_fsync,
+            background_rchar - other.background_rchar,
+            background_wchar - other.background_wchar,
+            background_read_bytes - other.background_read_bytes,
+            background_write_bytes - other.background_write_bytes,
+            background_fsync - other.background_fsync);
+    }
 }
diff --git a/car-lib/src/android/car/storagemonitoring/UidIoStats.java b/car-lib/src/android/car/storagemonitoring/UidIoStats.java
index 3b8ae93379..13db298ef9 100644
--- a/car-lib/src/android/car/storagemonitoring/UidIoStats.java
+++ b/car-lib/src/android/car/storagemonitoring/UidIoStats.java
@@ -66,15 +66,15 @@ public final class UidIoStats implements Parcelable {
     /**
      * Statistics for apps running in foreground.
      */
-    public final PerStateMetrics foreground;
+    public final UidIoStats.Metrics foreground;
 
     /**
      * Statistics for apps running in background.
      */
-    public final PerStateMetrics background;
+    public final UidIoStats.Metrics background;
 
     public UidIoStats(int uid,
-            long runtimeMillis, PerStateMetrics foreground, PerStateMetrics background) {
+            long runtimeMillis, UidIoStats.Metrics foreground, UidIoStats.Metrics background) {
         this.uid = uid;
         this.runtimeMillis = runtimeMillis;
         this.foreground = Objects.requireNonNull(foreground);
@@ -84,19 +84,19 @@ public final class UidIoStats implements Parcelable {
     public UidIoStats(Parcel in) {
         uid = in.readInt();
         runtimeMillis = in.readLong();
-        foreground = in.readParcelable(PerStateMetrics.class.getClassLoader());
-        background = in.readParcelable(PerStateMetrics.class.getClassLoader());
+        foreground = in.readParcelable(UidIoStats.Metrics.class.getClassLoader());
+        background = in.readParcelable(UidIoStats.Metrics.class.getClassLoader());
     }
 
-    public UidIoStats(UidIoStatsRecord record, long runtimeMillis) {
+    public UidIoStats(UidIoRecord record, long runtimeMillis) {
         uid = record.uid;
         this.runtimeMillis = runtimeMillis;
-        foreground = new PerStateMetrics(record.foreground_rchar,
+        foreground = new UidIoStats.Metrics(record.foreground_rchar,
                 record.foreground_wchar,
                 record.foreground_read_bytes,
                 record.foreground_write_bytes,
                 record.foreground_fsync);
-        background = new PerStateMetrics(record.background_rchar,
+        background = new UidIoStats.Metrics(record.background_rchar,
             record.background_wchar,
             record.background_read_bytes,
             record.background_write_bytes,
@@ -128,8 +128,8 @@ public final class UidIoStats implements Parcelable {
     public UidIoStats(JSONObject in) throws JSONException {
         uid = in.getInt("uid");
         runtimeMillis = in.getLong("runtimeMillis");
-        foreground = new PerStateMetrics(in.getJSONObject("foreground"));
-        background = new PerStateMetrics(in.getJSONObject("background"));
+        foreground = new UidIoStats.Metrics(in.getJSONObject("foreground"));
+        background = new UidIoStats.Metrics(in.getJSONObject("background"));
     }
 
     /**
@@ -181,7 +181,7 @@ public final class UidIoStats implements Parcelable {
      * It matches UID, and I/O activity values, but ignores runtime.
      * @hide
      */
-    public boolean representsSameMetrics(UidIoStatsRecord record) {
+    public boolean representsSameMetrics(UidIoRecord record) {
         return record.uid == uid &&
                record.foreground_rchar == foreground.bytesRead &&
                record.foreground_wchar == foreground.bytesWritten &&
@@ -198,16 +198,16 @@ public final class UidIoStats implements Parcelable {
     /**
      * I/O activity metrics that pertain to either the foreground or the background state.
      */
-    public static final class PerStateMetrics implements Parcelable {
+    public static final class Metrics implements Parcelable {
 
-        public static final Parcelable.Creator<PerStateMetrics> CREATOR =
-            new Parcelable.Creator<PerStateMetrics>() {
-                public PerStateMetrics createFromParcel(Parcel in) {
-                    return new PerStateMetrics(in);
+        public static final Parcelable.Creator<UidIoStats.Metrics> CREATOR =
+            new Parcelable.Creator<UidIoStats.Metrics>() {
+                public UidIoStats.Metrics createFromParcel(Parcel in) {
+                    return new UidIoStats.Metrics(in);
                 }
 
-                public PerStateMetrics[] newArray(int size) {
-                    return new PerStateMetrics[size];
+                public UidIoStats.Metrics[] newArray(int size) {
+                    return new UidIoStats.Metrics[size];
                 }
             };
 
@@ -240,7 +240,7 @@ public final class UidIoStats implements Parcelable {
          */
         public final long fsyncCalls;
 
-        public PerStateMetrics(long bytesRead, long bytesWritten, long bytesReadFromStorage,
+        public Metrics(long bytesRead, long bytesWritten, long bytesReadFromStorage,
             long bytesWrittenToStorage, long fsyncCalls) {
             this.bytesRead = bytesRead;
             this.bytesWritten = bytesWritten;
@@ -273,7 +273,7 @@ public final class UidIoStats implements Parcelable {
             jsonWriter.endObject();
         }
 
-        public PerStateMetrics(Parcel in) {
+        public Metrics(Parcel in) {
             bytesRead = in.readLong();
             bytesWritten = in.readLong();
             bytesReadFromStorage = in.readLong();
@@ -281,7 +281,7 @@ public final class UidIoStats implements Parcelable {
             fsyncCalls = in.readLong();
         }
 
-        public PerStateMetrics(JSONObject in) throws JSONException {
+        public Metrics(JSONObject in) throws JSONException {
             bytesRead = in.getLong("bytesRead");
             bytesWritten = in.getLong("bytesWritten");
             bytesReadFromStorage = in.getLong("bytesReadFromStorage");
@@ -298,8 +298,8 @@ public final class UidIoStats implements Parcelable {
          *
          * @hide
          */
-        public PerStateMetrics delta(PerStateMetrics other) {
-            return new PerStateMetrics(bytesRead-other.bytesRead,
+        public Metrics delta(Metrics other) {
+            return new Metrics(bytesRead-other.bytesRead,
                 bytesWritten-other.bytesWritten,
                 bytesReadFromStorage-other.bytesReadFromStorage,
                 bytesWrittenToStorage-other.bytesWrittenToStorage,
@@ -308,14 +308,14 @@ public final class UidIoStats implements Parcelable {
 
         @Override
         public boolean equals(Object other) {
-            if (other instanceof PerStateMetrics) {
-                PerStateMetrics perStateMetrics = (PerStateMetrics)other;
-
-                return (bytesRead == perStateMetrics.bytesRead) &&
-                    (bytesWritten == perStateMetrics.bytesWritten) &&
-                    (bytesReadFromStorage == perStateMetrics.bytesReadFromStorage) &&
-                    (bytesWrittenToStorage == perStateMetrics.bytesWrittenToStorage) &&
-                    (fsyncCalls == perStateMetrics.fsyncCalls);
+            if (other instanceof Metrics) {
+                Metrics metrics = (Metrics)other;
+
+                return (bytesRead == metrics.bytesRead) &&
+                    (bytesWritten == metrics.bytesWritten) &&
+                    (bytesReadFromStorage == metrics.bytesReadFromStorage) &&
+                    (bytesWrittenToStorage == metrics.bytesWrittenToStorage) &&
+                    (fsyncCalls == metrics.fsyncCalls);
             }
             return false;
         }
diff --git a/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.aidl b/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.aidl
new file mode 100644
index 0000000000..7ffb6f585e
--- /dev/null
+++ b/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2017 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.car.storagemonitoring;
+
+parcelable UidIoStatsDelta;
diff --git a/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.java b/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.java
new file mode 100644
index 0000000000..ffcd85f79f
--- /dev/null
+++ b/car-lib/src/android/car/storagemonitoring/UidIoStatsDelta.java
@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2017 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.car.storagemonitoring;
+
+import android.annotation.SystemApi;
+import android.car.storagemonitoring.UidIoStats.Metrics;
+import android.os.Parcel;
+import android.os.Parcelable;
+import java.util.List;
+import java.util.Objects;
+import java.util.StringJoiner;
+import java.util.stream.Collectors;
+
+/**
+ * Delta of uid_io stats taken at a sample point.
+ *
+ * @hide
+ */
+@SystemApi
+public class UidIoStatsDelta implements Parcelable {
+    public static final Creator<UidIoStatsDelta> CREATOR = new Creator<UidIoStatsDelta>() {
+        @Override
+        public UidIoStatsDelta createFromParcel(Parcel in) {
+            return new UidIoStatsDelta(in);
+        }
+
+        @Override
+        public UidIoStatsDelta[] newArray(int size) {
+            return new UidIoStatsDelta[size];
+        }
+    };
+
+    private final List<UidIoStats> mStats;
+    private final long mUptimeTimestamp;
+
+    public UidIoStatsDelta(List<UidIoStats> stats, long timestamp) {
+        mStats = stats;
+        mUptimeTimestamp = timestamp;
+    }
+
+    public UidIoStatsDelta(Parcel in) {
+        mStats = in.createTypedArrayList(UidIoStats.CREATOR);
+        mUptimeTimestamp = in.readLong();
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeTypedList(mStats);
+        dest.writeLong(mUptimeTimestamp);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    public long getTimestamp() {
+        return mUptimeTimestamp;
+    }
+
+    public List<UidIoStats> getStats() {
+        return mStats;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mStats, mUptimeTimestamp);
+    }
+
+    public UidIoStats getUserIdStats(int uid) {
+        for (UidIoStats stats : getStats()) {
+            if (stats.uid == uid) {
+                return stats;
+            }
+        }
+
+        return null;
+    }
+
+    public UidIoStats.Metrics getForegroundTotals() {
+        long bytesRead = 0;
+        long bytesWritten = 0;
+        long bytesReadFromStorage = 0;
+        long bytesWrittenToStorage = 0;
+        long fsyncCalls = 0;
+
+        for (UidIoStats stats : getStats()) {
+            bytesRead += stats.foreground.bytesRead;
+            bytesWritten += stats.foreground.bytesWritten;
+            bytesReadFromStorage += stats.foreground.bytesReadFromStorage;
+            bytesWrittenToStorage += stats.foreground.bytesWrittenToStorage;
+            fsyncCalls += stats.foreground.fsyncCalls;
+        }
+
+        return new Metrics(bytesRead,
+                bytesWritten,
+                bytesReadFromStorage,
+                bytesWrittenToStorage,
+                fsyncCalls);
+    }
+
+    public UidIoStats.Metrics getBackgroundTotals() {
+        long bytesRead = 0;
+        long bytesWritten = 0;
+        long bytesReadFromStorage = 0;
+        long bytesWrittenToStorage = 0;
+        long fsyncCalls = 0;
+
+        for (UidIoStats stats : getStats()) {
+            bytesRead += stats.background.bytesRead;
+            bytesWritten += stats.background.bytesWritten;
+            bytesReadFromStorage += stats.background.bytesReadFromStorage;
+            bytesWrittenToStorage += stats.background.bytesWrittenToStorage;
+            fsyncCalls += stats.background.fsyncCalls;
+        }
+
+        return new Metrics(bytesRead,
+            bytesWritten,
+            bytesReadFromStorage,
+            bytesWrittenToStorage,
+            fsyncCalls);
+    }
+
+    public UidIoStats.Metrics getTotals() {
+        UidIoStats.Metrics foreground = getForegroundTotals();
+        UidIoStats.Metrics background = getBackgroundTotals();
+
+        return new UidIoStats.Metrics(foreground.bytesRead + background.bytesRead,
+                foreground.bytesWritten + background.bytesWritten,
+                foreground.bytesReadFromStorage + background.bytesReadFromStorage,
+                foreground.bytesWrittenToStorage + background.bytesWrittenToStorage,
+                foreground.fsyncCalls + background.fsyncCalls);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other instanceof UidIoStatsDelta) {
+            UidIoStatsDelta delta = (UidIoStatsDelta)other;
+            return delta.getTimestamp() == getTimestamp() &&
+                delta.getStats().equals(getStats());
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        StringJoiner stringJoiner = new StringJoiner(", ");
+        for (UidIoStats stats : getStats()) {
+            stringJoiner.add(stats.toString());
+        }
+        return "timestamp = " + getTimestamp() + ", stats = " + stringJoiner.toString();
+    }
+}