1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.internal.util;
18
19import android.os.Debug;
20import android.os.StrictMode;
21
22public final class MemInfoReader {
23    final long[] mInfos = new long[Debug.MEMINFO_COUNT];
24
25    public void readMemInfo() {
26        // Permit disk reads here, as /proc/meminfo isn't really "on
27        // disk" and should be fast.  TODO: make BlockGuard ignore
28        // /proc/ and /sys/ files perhaps?
29        StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
30        try {
31            Debug.getMemInfo(mInfos);
32        } finally {
33            StrictMode.setThreadPolicy(savedPolicy);
34        }
35    }
36
37    /**
38     * Total amount of RAM available to the kernel.
39     */
40    public long getTotalSize() {
41        return mInfos[Debug.MEMINFO_TOTAL] * 1024;
42    }
43
44    /**
45     * Amount of RAM that is not being used for anything.
46     */
47    public long getFreeSize() {
48        return mInfos[Debug.MEMINFO_FREE] * 1024;
49    }
50
51    /**
52     * Amount of RAM that the kernel is being used for caches, not counting caches
53     * that are mapped in to processes.
54     */
55    public long getCachedSize() {
56        return getCachedSizeKb() * 1024;
57    }
58
59    /**
60     * Amount of RAM that is in use by the kernel for actual allocations.
61     */
62    public long getKernelUsedSize() {
63        return getKernelUsedSizeKb() * 1024;
64    }
65
66    /**
67     * Total amount of RAM available to the kernel.
68     */
69    public long getTotalSizeKb() {
70        return mInfos[Debug.MEMINFO_TOTAL];
71    }
72
73    /**
74     * Amount of RAM that is not being used for anything.
75     */
76    public long getFreeSizeKb() {
77        return mInfos[Debug.MEMINFO_FREE];
78    }
79
80    /**
81     * Amount of RAM that the kernel is being used for caches, not counting caches
82     * that are mapped in to processes.
83     */
84    public long getCachedSizeKb() {
85        return mInfos[Debug.MEMINFO_BUFFERS]
86                + mInfos[Debug.MEMINFO_CACHED] - mInfos[Debug.MEMINFO_MAPPED];
87    }
88
89    /**
90     * Amount of RAM that is in use by the kernel for actual allocations.
91     */
92    public long getKernelUsedSizeKb() {
93        return mInfos[Debug.MEMINFO_SHMEM] + mInfos[Debug.MEMINFO_SLAB]
94                + mInfos[Debug.MEMINFO_VM_ALLOC_USED] + mInfos[Debug.MEMINFO_PAGE_TABLES]
95                + mInfos[Debug.MEMINFO_KERNEL_STACK];
96    }
97
98    public long getSwapTotalSizeKb() {
99        return mInfos[Debug.MEMINFO_SWAP_TOTAL];
100    }
101
102    public long getSwapFreeSizeKb() {
103        return mInfos[Debug.MEMINFO_SWAP_FREE];
104    }
105
106    public long getZramTotalSizeKb() {
107        return mInfos[Debug.MEMINFO_ZRAM_TOTAL];
108    }
109
110    public long[] getRawInfo() {
111        return mInfos;
112    }
113}
114