1 /*
2  * Copyright (C) 2012 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 "space_bitmap.h"
18 
19 #include <stdint.h>
20 #include <memory>
21 
22 #include "common_runtime_test.h"
23 #include "globals.h"
24 #include "space_bitmap-inl.h"
25 
26 namespace art {
27 namespace gc {
28 namespace accounting {
29 
30 class SpaceBitmapTest : public CommonRuntimeTest {};
31 
TEST_F(SpaceBitmapTest,Init)32 TEST_F(SpaceBitmapTest, Init) {
33   uint8_t* heap_begin = reinterpret_cast<uint8_t*>(0x10000000);
34   size_t heap_capacity = 16 * MB;
35   std::unique_ptr<ContinuousSpaceBitmap> space_bitmap(
36       ContinuousSpaceBitmap::Create("test bitmap", heap_begin, heap_capacity));
37   EXPECT_TRUE(space_bitmap.get() != nullptr);
38 }
39 
40 class BitmapVerify {
41  public:
BitmapVerify(ContinuousSpaceBitmap * bitmap,const mirror::Object * begin,const mirror::Object * end)42   BitmapVerify(ContinuousSpaceBitmap* bitmap, const mirror::Object* begin,
43                const mirror::Object* end)
44     : bitmap_(bitmap),
45       begin_(begin),
46       end_(end) {}
47 
operator ()(const mirror::Object * obj)48   void operator()(const mirror::Object* obj) {
49     EXPECT_TRUE(obj >= begin_);
50     EXPECT_TRUE(obj <= end_);
51     EXPECT_EQ(bitmap_->Test(obj), ((reinterpret_cast<uintptr_t>(obj) & 0xF) != 0));
52   }
53 
54   ContinuousSpaceBitmap* const bitmap_;
55   const mirror::Object* begin_;
56   const mirror::Object* end_;
57 };
58 
TEST_F(SpaceBitmapTest,ScanRange)59 TEST_F(SpaceBitmapTest, ScanRange) {
60   uint8_t* heap_begin = reinterpret_cast<uint8_t*>(0x10000000);
61   size_t heap_capacity = 16 * MB;
62 
63   std::unique_ptr<ContinuousSpaceBitmap> space_bitmap(
64       ContinuousSpaceBitmap::Create("test bitmap", heap_begin, heap_capacity));
65   EXPECT_TRUE(space_bitmap.get() != nullptr);
66 
67   // Set all the odd bits in the first BitsPerIntPtrT * 3 to one.
68   for (size_t j = 0; j < kBitsPerIntPtrT * 3; ++j) {
69     const mirror::Object* obj =
70         reinterpret_cast<mirror::Object*>(heap_begin + j * kObjectAlignment);
71     if (reinterpret_cast<uintptr_t>(obj) & 0xF) {
72       space_bitmap->Set(obj);
73     }
74   }
75   // Try every possible starting bit in the first word. Then for each starting bit, try each
76   // possible length up to a maximum of kBitsPerWord * 2 - 1 bits.
77   // This handles all the cases, having runs which start and end on the same word, and different
78   // words.
79   for (size_t i = 0; i < static_cast<size_t>(kBitsPerIntPtrT); ++i) {
80     mirror::Object* start =
81         reinterpret_cast<mirror::Object*>(heap_begin + i * kObjectAlignment);
82     for (size_t j = 0; j < static_cast<size_t>(kBitsPerIntPtrT * 2); ++j) {
83       mirror::Object* end =
84           reinterpret_cast<mirror::Object*>(heap_begin + (i + j) * kObjectAlignment);
85       BitmapVerify(space_bitmap.get(), start, end);
86     }
87   }
88 }
89 
90 class SimpleCounter {
91  public:
SimpleCounter(size_t * counter)92   explicit SimpleCounter(size_t* counter) : count_(counter) {}
93 
operator ()(mirror::Object * obj ATTRIBUTE_UNUSED) const94   void operator()(mirror::Object* obj ATTRIBUTE_UNUSED) const {
95     (*count_)++;
96   }
97 
98   size_t* const count_;
99 };
100 
101 class RandGen {
102  public:
RandGen(uint32_t seed)103   explicit RandGen(uint32_t seed) : val_(seed) {}
104 
next()105   uint32_t next() {
106     val_ = val_ * 48271 % 2147483647;
107     return val_;
108   }
109 
110   uint32_t val_;
111 };
112 
113 template <size_t kAlignment>
RunTest()114 void RunTest() NO_THREAD_SAFETY_ANALYSIS {
115   uint8_t* heap_begin = reinterpret_cast<uint8_t*>(0x10000000);
116   size_t heap_capacity = 16 * MB;
117 
118   // Seed with 0x1234 for reproducability.
119   RandGen r(0x1234);
120 
121 
122   for (int i = 0; i < 5 ; ++i) {
123     std::unique_ptr<ContinuousSpaceBitmap> space_bitmap(
124         ContinuousSpaceBitmap::Create("test bitmap", heap_begin, heap_capacity));
125 
126     for (int j = 0; j < 10000; ++j) {
127       size_t offset = RoundDown(r.next() % heap_capacity, kAlignment);
128       bool set = r.next() % 2 == 1;
129 
130       if (set) {
131         space_bitmap->Set(reinterpret_cast<mirror::Object*>(heap_begin + offset));
132       } else {
133         space_bitmap->Clear(reinterpret_cast<mirror::Object*>(heap_begin + offset));
134       }
135     }
136 
137     for (int j = 0; j < 50; ++j) {
138       size_t count = 0;
139       SimpleCounter c(&count);
140 
141       size_t offset = RoundDown(r.next() % heap_capacity, kAlignment);
142       size_t remain = heap_capacity - offset;
143       size_t end = offset + RoundDown(r.next() % (remain + 1), kAlignment);
144 
145       space_bitmap->VisitMarkedRange(reinterpret_cast<uintptr_t>(heap_begin) + offset,
146                                      reinterpret_cast<uintptr_t>(heap_begin) + end, c);
147 
148       size_t manual = 0;
149       for (uintptr_t k = offset; k < end; k += kAlignment) {
150         if (space_bitmap->Test(reinterpret_cast<mirror::Object*>(heap_begin + k))) {
151           manual++;
152         }
153       }
154 
155       EXPECT_EQ(count, manual);
156     }
157   }
158 }
159 
TEST_F(SpaceBitmapTest,VisitorObjectAlignment)160 TEST_F(SpaceBitmapTest, VisitorObjectAlignment) {
161   RunTest<kObjectAlignment>();
162 }
163 
TEST_F(SpaceBitmapTest,VisitorPageAlignment)164 TEST_F(SpaceBitmapTest, VisitorPageAlignment) {
165   RunTest<kPageSize>();
166 }
167 
168 }  // namespace accounting
169 }  // namespace gc
170 }  // namespace art
171