content: /*
   * Copyright (C) 2011 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.internal.util;
  
  import android.annotation.UnsupportedAppUsage;
  import android.os.Debug;
  import android.os.StrictMode;
  
  public final class MemInfoReader {
      final long[] mInfos = new long[Debug.MEMINFO_COUNT];
  
      @UnsupportedAppUsage
      public void readMemInfo() {
          // Permit disk reads here, as /proc/meminfo isn't really "on
          // disk" and should be fast.  TODO: make BlockGuard ignore
          // /proc/ and /sys/ files perhaps?
          StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
          try {
              Debug.getMemInfo(mInfos);
          } finally {
              StrictMode.setThreadPolicy(savedPolicy);
          }
      }
  
      /**
       * Total amount of RAM available to the kernel.
       */
      @UnsupportedAppUsage
      public long getTotalSize() {
          return mInfos[Debug.MEMINFO_TOTAL] * 1024;
      }
  
      /**
       * Amount of RAM that is not being used for anything.
       */
      @UnsupportedAppUsage
      public long getFreeSize() {
          return mInfos[Debug.MEMINFO_FREE] * 1024;
      }
  
      /**
       * Amount of RAM that the kernel is being used for caches, not counting caches
       * that are mapped in to processes.
       */
      @UnsupportedAppUsage
      public long getCachedSize() {
          return getCachedSizeKb() * 1024;
      }
  
      /**
       * Amount of RAM that is in use by the kernel for actual allocations.
       */
      public long getKernelUsedSize() {
          return getKernelUsedSizeKb() * 1024;
      }
  
      /**
       * Total amount of RAM available to the kernel.
       */
      public long getTotalSizeKb() {
          return mInfos[Debug.MEMINFO_TOTAL];
      }
  
      /**
       * Amount of RAM that is not being used for anything.
       */
      public long getFreeSizeKb() {
          return mInfos[Debug.MEMINFO_FREE];
      }
  
      /**
       * Amount of RAM that the kernel is being used for caches, not counting caches
       * that are mapped in to processes.
       */
      public long getCachedSizeKb() {
          return mInfos[Debug.MEMINFO_BUFFERS] + mInfos[Debug.MEMINFO_SLAB_RECLAIMABLE]
                  + mInfos[Debug.MEMINFO_CACHED] - mInfos[Debug.MEMINFO_MAPPED];
      }
  
      /**
       * Amount of RAM that is in use by the kernel for actual allocations.
       */
      public long getKernelUsedSizeKb() {
          return mInfos[Debug.MEMINFO_SHMEM] + mInfos[Debug.MEMINFO_SLAB_UNRECLAIMABLE]
                  + mInfos[Debug.MEMINFO_VM_ALLOC_USED] + mInfos[Debug.MEMINFO_PAGE_TABLES]
                  + mInfos[Debug.MEMINFO_KERNEL_STACK];
      }
  
      public long getSwapTotalSizeKb() {
          return mInfos[Debug.MEMINFO_SWAP_TOTAL];
      }
  
      public long getSwapFreeSizeKb() {
          return mInfos[Debug.MEMINFO_SWAP_FREE];
      }
  
      public long getZramTotalSizeKb() {
          return mInfos[Debug.MEMINFO_ZRAM_TOTAL];
      }
  
      @UnsupportedAppUsage
      public long[] getRawInfo() {
          return mInfos;
      }
  }
  