1 /*
2 * Copyright (C) 2015 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 #include "bitmap-inl.h"
18
19 #include <sys/mman.h> // For the PROT_* and MAP_* constants.
20
21 #include "base/bit_utils.h"
22 #include "card_table.h"
23 #include "jit/jit_code_cache.h"
24 #include "mem_map.h"
25
26 namespace art {
27 namespace gc {
28 namespace accounting {
29
CreateFromMemMap(MemMap * mem_map,size_t num_bits)30 Bitmap* Bitmap::CreateFromMemMap(MemMap* mem_map, size_t num_bits) {
31 CHECK(mem_map != nullptr);
32 return new Bitmap(mem_map, num_bits);
33 }
34
Bitmap(MemMap * mem_map,size_t bitmap_size)35 Bitmap::Bitmap(MemMap* mem_map, size_t bitmap_size)
36 : mem_map_(mem_map), bitmap_begin_(reinterpret_cast<uintptr_t*>(mem_map->Begin())),
37 bitmap_size_(bitmap_size) {
38 CHECK(bitmap_begin_ != nullptr);
39 CHECK_NE(bitmap_size, 0U);
40 }
41
~Bitmap()42 Bitmap::~Bitmap() {
43 // Destroys MemMap via std::unique_ptr<>.
44 }
45
AllocateMemMap(const std::string & name,size_t num_bits)46 MemMap* Bitmap::AllocateMemMap(const std::string& name, size_t num_bits) {
47 const size_t bitmap_size = RoundUp(
48 RoundUp(num_bits, kBitsPerBitmapWord) / kBitsPerBitmapWord * sizeof(uintptr_t), kPageSize);
49 std::string error_msg;
50 std::unique_ptr<MemMap> mem_map(MemMap::MapAnonymous(name.c_str(), nullptr, bitmap_size,
51 PROT_READ | PROT_WRITE, false, false,
52 &error_msg));
53 if (UNLIKELY(mem_map.get() == nullptr)) {
54 LOG(ERROR) << "Failed to allocate bitmap " << name << ": " << error_msg;
55 return nullptr;
56 }
57 return mem_map.release();
58 }
59
Create(const std::string & name,size_t num_bits)60 Bitmap* Bitmap::Create(const std::string& name, size_t num_bits) {
61 auto* const mem_map = AllocateMemMap(name, num_bits);
62 if (mem_map == nullptr) {
63 return nullptr;
64 }
65 return CreateFromMemMap(mem_map, num_bits);
66 }
67
Clear()68 void Bitmap::Clear() {
69 if (bitmap_begin_ != nullptr) {
70 mem_map_->MadviseDontNeedAndZero();
71 }
72 }
73
CopyFrom(Bitmap * source_bitmap)74 void Bitmap::CopyFrom(Bitmap* source_bitmap) {
75 DCHECK_EQ(BitmapSize(), source_bitmap->BitmapSize());
76 std::copy(source_bitmap->Begin(),
77 source_bitmap->Begin() + BitmapSize() / kBitsPerBitmapWord, Begin());
78 }
79
80 template<size_t kAlignment>
Create(const std::string & name,uintptr_t cover_begin,uintptr_t cover_end)81 MemoryRangeBitmap<kAlignment>* MemoryRangeBitmap<kAlignment>::Create(
82 const std::string& name, uintptr_t cover_begin, uintptr_t cover_end) {
83 CHECK_ALIGNED(cover_begin, kAlignment);
84 CHECK_ALIGNED(cover_end, kAlignment);
85 const size_t num_bits = (cover_end - cover_begin) / kAlignment;
86 auto* const mem_map = Bitmap::AllocateMemMap(name, num_bits);
87 return CreateFromMemMap(mem_map, cover_begin, num_bits);
88 }
89
90 template<size_t kAlignment>
CreateFromMemMap(MemMap * mem_map,uintptr_t begin,size_t num_bits)91 MemoryRangeBitmap<kAlignment>* MemoryRangeBitmap<kAlignment>::CreateFromMemMap(
92 MemMap* mem_map, uintptr_t begin, size_t num_bits) {
93 return new MemoryRangeBitmap(mem_map, begin, num_bits);
94 }
95
96 template class MemoryRangeBitmap<CardTable::kCardSize>;
97 template class MemoryRangeBitmap<jit::kJitCodeAlignment>;
98
99 } // namespace accounting
100 } // namespace gc
101 } // namespace art
102
103