1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <malloc.h>
30 #include <unistd.h>
31 
32 #include <vector>
33 
34 #include <benchmark/benchmark.h>
35 #include "util.h"
36 
37 #if defined(__BIONIC__)
38 
BM_mallopt_purge(benchmark::State & state)39 static void BM_mallopt_purge(benchmark::State& state) {
40   static size_t sizes[] = {8, 16, 32, 64, 128, 1024, 4096, 16384, 65536, 131072, 1048576};
41   static int pagesize = getpagesize();
42   mallopt(M_DECAY_TIME, 1);
43   mallopt(M_PURGE, 0);
44   for (auto _ : state) {
45     state.PauseTiming();
46     std::vector<void*> ptrs;
47     for (auto size : sizes) {
48       // Allocate at least two pages worth of the allocations.
49       for (size_t allocated = 0; allocated < 2 * static_cast<size_t>(pagesize); allocated += size) {
50         void* ptr = malloc(size);
51         if (ptr == nullptr) {
52           state.SkipWithError("Failed to allocate memory");
53         }
54         MakeAllocationResident(ptr, size, pagesize);
55         ptrs.push_back(ptr);
56       }
57     }
58     // Free the memory, which should leave many of the pages resident until
59     // the purge call.
60     for (auto ptr : ptrs) {
61       free(ptr);
62     }
63     ptrs.clear();
64     state.ResumeTiming();
65 
66     mallopt(M_PURGE, 0);
67   }
68   mallopt(M_DECAY_TIME, 0);
69 }
70 BIONIC_BENCHMARK(BM_mallopt_purge);
71 
72 #endif
73