[go: nahoru, domu]
1/*
2 * Copyright (C) 2016 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
17#define LOG_TAG "MediaUtils"
18#define LOG_NDEBUG 0
19#include <utils/Log.h>
20
21#include <cutils/properties.h>
22#include <sys/resource.h>
23#include <unistd.h>
24
25#include "MediaUtils.h"
26
27namespace android {
28
29void limitProcessMemory(
30    const char *property,
31    size_t numberOfBytes,
32    size_t percentageOfTotalMem) {
33
34    long pageSize = sysconf(_SC_PAGESIZE);
35    long numPages = sysconf(_SC_PHYS_PAGES);
36    size_t maxMem = SIZE_MAX;
37
38    if (pageSize > 0 && numPages > 0) {
39        if (size_t(numPages) < SIZE_MAX / size_t(pageSize)) {
40            maxMem = size_t(numPages) * size_t(pageSize);
41        }
42        ALOGV("physMem: %zu", maxMem);
43        if (percentageOfTotalMem > 100) {
44            ALOGW("requested %zu%% of total memory, using 100%%", percentageOfTotalMem);
45            percentageOfTotalMem = 100;
46        }
47        maxMem = maxMem / 100 * percentageOfTotalMem;
48        if (numberOfBytes < maxMem) {
49            maxMem = numberOfBytes;
50        }
51        ALOGV("requested limit: %zu", maxMem);
52    } else {
53        ALOGW("couldn't determine total RAM");
54    }
55
56    int64_t propVal = property_get_int64(property, maxMem);
57    if (propVal > 0 && uint64_t(propVal) <= SIZE_MAX) {
58        maxMem = propVal;
59    }
60    ALOGV("actual limit: %zu", maxMem);
61
62    struct rlimit limit;
63    getrlimit(RLIMIT_AS, &limit);
64    ALOGV("original limits: %lld/%lld", (long long)limit.rlim_cur, (long long)limit.rlim_max);
65    limit.rlim_cur = maxMem;
66    setrlimit(RLIMIT_AS, &limit);
67    limit.rlim_cur = -1;
68    limit.rlim_max = -1;
69    getrlimit(RLIMIT_AS, &limit);
70    ALOGV("new limits: %lld/%lld", (long long)limit.rlim_cur, (long long)limit.rlim_max);
71
72}
73
74} // namespace android
75