| /* |
| * Copyright (C) 2020 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 com.android.server; |
| |
| import android.os.StrictMode; |
| import android.util.Slog; |
| |
| import libcore.io.IoUtils; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.io.StringWriter; |
| |
| /** |
| * Utility method for memory pressure (PSI). |
| */ |
| public final class MemoryPressureUtil { |
| private static final String FILE = "/proc/pressure/memory"; |
| private static final String TAG = "MemoryPressure"; |
| |
| /** |
| * @return a stanza about memory PSI to add to a report. |
| */ |
| public static String currentPsiState() { |
| final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads(); |
| StringWriter contents = new StringWriter(); |
| try { |
| if (new File(FILE).exists()) { |
| contents.append("----- Output from /proc/pressure/memory -----\n"); |
| contents.append(IoUtils.readFileAsString(FILE)); |
| contents.append("----- End output from /proc/pressure/memory -----\n\n"); |
| } |
| } catch (IOException e) { |
| Slog.e(TAG, "Could not read " + FILE, e); |
| } finally { |
| StrictMode.setThreadPolicy(savedPolicy); |
| } |
| return contents.toString(); |
| } |
| |
| private MemoryPressureUtil(){} |
| } |