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 <bionic/malloc.h>
26 #include <mediautils/LimitProcessMemory.h>
27 
28 extern "C" void __scudo_set_rss_limit(size_t, int) __attribute__((weak));
29 
30 namespace android {
31 
limitProcessMemory(const char * property,size_t numberOfBytes,size_t percentageOfTotalMem)32 void limitProcessMemory(const char *property, size_t numberOfBytes,
33                         size_t percentageOfTotalMem) {
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 
61     // If Scudo is in use, enforce the hard RSS limit (in MB).
62     if (maxMem != SIZE_MAX && &__scudo_set_rss_limit != 0) {
63       __scudo_set_rss_limit(maxMem >> 20, 1);
64       ALOGV("Scudo hard RSS limit set to %zu MB", maxMem >> 20);
65       return;
66     }
67 
68     if (!android_mallopt(M_SET_ALLOCATION_LIMIT_BYTES, &maxMem,
69                          sizeof(maxMem))) {
70       ALOGW("couldn't set allocation limit");
71     }
72 }
73 
74 } // namespace android
75