1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "absl/base/internal/malloc_extension.h"
#include <assert.h>
#include <string.h>
#include <atomic>
#include <string>
#include "absl/base/dynamic_annotations.h"
#include "absl/base/internal/malloc_extension_c.h"
namespace absl {
namespace base_internal {
// SysAllocator implementation
SysAllocator::~SysAllocator() {}
void SysAllocator::GetStats(char* buffer, int) { buffer[0] = 0; }
// Default implementation -- does nothing
MallocExtension::~MallocExtension() { }
bool MallocExtension::VerifyAllMemory() { return true; }
bool MallocExtension::VerifyNewMemory(const void*) { return true; }
bool MallocExtension::VerifyArrayNewMemory(const void*) { return true; }
bool MallocExtension::VerifyMallocMemory(const void*) { return true; }
bool MallocExtension::GetNumericProperty(const char*, size_t*) {
return false;
}
bool MallocExtension::SetNumericProperty(const char*, size_t) {
return false;
}
void MallocExtension::GetStats(char* buffer, int length) {
assert(length > 0);
static_cast<void>(length);
buffer[0] = '\0';
}
bool MallocExtension::MallocMemoryStats(int* blocks, size_t* total,
int histogram[kMallocHistogramSize]) {
*blocks = 0;
*total = 0;
memset(histogram, 0, sizeof(*histogram) * kMallocHistogramSize);
return true;
}
void MallocExtension::MarkThreadIdle() {
// Default implementation does nothing
}
void MallocExtension::MarkThreadBusy() {
// Default implementation does nothing
}
SysAllocator* MallocExtension::GetSystemAllocator() {
return nullptr;
}
void MallocExtension::SetSystemAllocator(SysAllocator*) {
// Default implementation does nothing
}
void MallocExtension::ReleaseToSystem(size_t) {
// Default implementation does nothing
}
void MallocExtension::ReleaseFreeMemory() {
ReleaseToSystem(static_cast<size_t>(-1)); // SIZE_T_MAX
}
void MallocExtension::SetMemoryReleaseRate(double) {
// Default implementation does nothing
}
double MallocExtension::GetMemoryReleaseRate() {
return -1.0;
}
size_t MallocExtension::GetEstimatedAllocatedSize(size_t size) {
return size;
}
size_t MallocExtension::GetAllocatedSize(const void* p) {
assert(GetOwnership(p) != kNotOwned);
static_cast<void>(p);
return 0;
}
MallocExtension::Ownership MallocExtension::GetOwnership(const void*) {
return kUnknownOwnership;
}
void MallocExtension::GetProperties(MallocExtension::StatLevel,
std::map<std::string, Property>* result) {
result->clear();
}
size_t MallocExtension::ReleaseCPUMemory(int) {
return 0;
}
// The current malloc extension object.
std::atomic<MallocExtension*> MallocExtension::current_instance_;
MallocExtension* MallocExtension::InitModule() {
MallocExtension* ext = new MallocExtension;
current_instance_.store(ext, std::memory_order_release);
return ext;
}
void MallocExtension::Register(MallocExtension* implementation) {
InitModuleOnce();
// When running under valgrind, our custom malloc is replaced with
// valgrind's one and malloc extensions will not work. (Note:
// callers should be responsible for checking that they are the
// malloc that is really being run, before calling Register. This
// is just here as an extra sanity check.)
// Under compiler-based ThreadSanitizer RunningOnValgrind() returns true,
// but we still want to use malloc extensions.
#ifndef THREAD_SANITIZER
if (RunningOnValgrind()) {
return;
}
#endif // #ifndef THREAD_SANITIZER
current_instance_.store(implementation, std::memory_order_release);
}
void MallocExtension::GetHeapSample(MallocExtensionWriter*) {}
void MallocExtension::GetHeapGrowthStacks(MallocExtensionWriter*) {}
void MallocExtension::GetFragmentationProfile(MallocExtensionWriter*) {}
} // namespace base_internal
} // namespace absl
// These are C shims that work on the current instance.
#define C_SHIM(fn, retval, paramlist, arglist) \
extern "C" retval MallocExtension_##fn paramlist { \
return absl::base_internal::MallocExtension::instance()->fn arglist; \
}
C_SHIM(VerifyAllMemory, int, (void), ());
C_SHIM(VerifyNewMemory, int, (const void* p), (p));
C_SHIM(VerifyArrayNewMemory, int, (const void* p), (p));
C_SHIM(VerifyMallocMemory, int, (const void* p), (p));
C_SHIM(
MallocMemoryStats, int,
(int* blocks, size_t* total,
int histogram[absl::base_internal::MallocExtension::kMallocHistogramSize]),
(blocks, total, histogram));
C_SHIM(GetStats, void,
(char* buffer, int buffer_length), (buffer, buffer_length));
C_SHIM(GetNumericProperty, int,
(const char* property, size_t* value), (property, value));
C_SHIM(SetNumericProperty, int,
(const char* property, size_t value), (property, value));
C_SHIM(MarkThreadIdle, void, (void), ());
C_SHIM(MarkThreadBusy, void, (void), ());
C_SHIM(ReleaseFreeMemory, void, (void), ());
C_SHIM(ReleaseToSystem, void, (size_t num_bytes), (num_bytes));
C_SHIM(GetEstimatedAllocatedSize, size_t, (size_t size), (size));
C_SHIM(GetAllocatedSize, size_t, (const void* p), (p));
// Can't use the shim here because of the need to translate the enums.
extern "C"
MallocExtension_Ownership MallocExtension_GetOwnership(const void* p) {
return static_cast<MallocExtension_Ownership>(
absl::base_internal::MallocExtension::instance()->GetOwnership(p));
}
// Default implementation just returns size. The expectation is that
// the linked-in malloc implementation might provide an override of
// this weak function with a better implementation.
ABSL_ATTRIBUTE_WEAK ABSL_ATTRIBUTE_NOINLINE size_t nallocx(size_t size, int) {
return size;
}
|
