forked from mrsone40/node
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathallocation.cc
More file actions
391 lines (333 loc) · 13.1 KB
/
allocation.cc
File metadata and controls
391 lines (333 loc) · 13.1 KB
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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/utils/allocation.h"
#include <stdlib.h> // For free, malloc.
#include "src/base/bits.h"
#include "src/base/bounded-page-allocator.h"
#include "src/base/lazy-instance.h"
#include "src/base/logging.h"
#include "src/base/page-allocator.h"
#include "src/base/platform/memory.h"
#include "src/base/sanitizer/lsan-page-allocator.h"
#include "src/base/sanitizer/lsan-virtual-address-space.h"
#include "src/base/virtual-address-space.h"
#include "src/flags/flags.h"
#include "src/init/v8.h"
#include "src/sandbox/sandbox.h"
#include "src/utils/memcopy.h"
#if V8_LIBC_BIONIC
#include <malloc.h>
#endif
namespace v8 {
namespace internal {
namespace {
class PageAllocatorInitializer {
public:
PageAllocatorInitializer() {
page_allocator_ = V8::GetCurrentPlatform()->GetPageAllocator();
if (page_allocator_ == nullptr) {
static base::LeakyObject<base::PageAllocator> default_page_allocator;
page_allocator_ = default_page_allocator.get();
}
#if defined(LEAK_SANITIZER)
static base::LeakyObject<base::LsanPageAllocator> lsan_allocator(
page_allocator_);
page_allocator_ = lsan_allocator.get();
#endif
}
PageAllocator* page_allocator() const { return page_allocator_; }
void SetPageAllocatorForTesting(PageAllocator* allocator) {
page_allocator_ = allocator;
}
private:
PageAllocator* page_allocator_;
};
DEFINE_LAZY_LEAKY_OBJECT_GETTER(PageAllocatorInitializer,
GetPageAllocatorInitializer)
// We will attempt allocation this many times. After each failure, we call
// OnCriticalMemoryPressure to try to free some memory.
const int kAllocationTries = 2;
} // namespace
v8::PageAllocator* GetPlatformPageAllocator() {
DCHECK_NOT_NULL(GetPageAllocatorInitializer()->page_allocator());
return GetPageAllocatorInitializer()->page_allocator();
}
v8::VirtualAddressSpace* GetPlatformVirtualAddressSpace() {
#if defined(LEAK_SANITIZER)
static base::LeakyObject<base::LsanVirtualAddressSpace> vas(
std::make_unique<base::VirtualAddressSpace>());
#else
static base::LeakyObject<base::VirtualAddressSpace> vas;
#endif
return vas.get();
}
#ifdef V8_ENABLE_SANDBOX
v8::PageAllocator* GetSandboxPageAllocator() {
CHECK(GetProcessWideSandbox()->is_initialized());
return GetProcessWideSandbox()->page_allocator();
}
#endif
v8::PageAllocator* SetPlatformPageAllocatorForTesting(
v8::PageAllocator* new_page_allocator) {
v8::PageAllocator* old_page_allocator = GetPlatformPageAllocator();
GetPageAllocatorInitializer()->SetPageAllocatorForTesting(new_page_allocator);
return old_page_allocator;
}
void* Malloced::operator new(size_t size) {
void* result = AllocWithRetry(size);
if (V8_UNLIKELY(result == nullptr)) {
V8::FatalProcessOutOfMemory(nullptr, "Malloced operator new");
}
return result;
}
void Malloced::operator delete(void* p) { base::Free(p); }
char* StrDup(const char* str) {
size_t length = strlen(str);
char* result = NewArray<char>(length + 1);
MemCopy(result, str, length);
result[length] = '\0';
return result;
}
char* StrNDup(const char* str, size_t n) {
size_t length = strlen(str);
if (n < length) length = n;
char* result = NewArray<char>(length + 1);
MemCopy(result, str, length);
result[length] = '\0';
return result;
}
void* AllocWithRetry(size_t size, MallocFn malloc_fn) {
void* result = nullptr;
for (int i = 0; i < kAllocationTries; ++i) {
result = malloc_fn(size);
if (V8_LIKELY(result != nullptr)) break;
OnCriticalMemoryPressure();
}
return result;
}
base::AllocationResult<void*> AllocAtLeastWithRetry(size_t size) {
base::AllocationResult<char*> result = {nullptr, 0u};
for (int i = 0; i < kAllocationTries; ++i) {
result = base::AllocateAtLeast<char>(size);
if (V8_LIKELY(result.ptr != nullptr)) break;
OnCriticalMemoryPressure();
}
return {result.ptr, result.count};
}
void* AlignedAllocWithRetry(size_t size, size_t alignment) {
void* result = nullptr;
for (int i = 0; i < kAllocationTries; ++i) {
result = base::AlignedAlloc(size, alignment);
if (V8_LIKELY(result != nullptr)) return result;
OnCriticalMemoryPressure();
}
V8::FatalProcessOutOfMemory(nullptr, "AlignedAlloc");
}
void AlignedFree(void* ptr) { base::AlignedFree(ptr); }
size_t AllocatePageSize() {
return GetPlatformPageAllocator()->AllocatePageSize();
}
size_t CommitPageSize() { return GetPlatformPageAllocator()->CommitPageSize(); }
void* GetRandomMmapAddr() {
return GetPlatformPageAllocator()->GetRandomMmapAddr();
}
void* AllocatePages(v8::PageAllocator* page_allocator, void* hint, size_t size,
size_t alignment, PageAllocator::Permission access) {
DCHECK_NOT_NULL(page_allocator);
DCHECK(IsAligned(reinterpret_cast<Address>(hint), alignment));
DCHECK(IsAligned(size, page_allocator->AllocatePageSize()));
if (!hint && v8_flags.randomize_all_allocations) {
hint = AlignedAddress(page_allocator->GetRandomMmapAddr(), alignment);
}
void* result = nullptr;
for (int i = 0; i < kAllocationTries; ++i) {
result = page_allocator->AllocatePages(hint, size, alignment, access);
if (V8_LIKELY(result != nullptr)) break;
OnCriticalMemoryPressure();
}
return result;
}
void FreePages(v8::PageAllocator* page_allocator, void* address,
const size_t size) {
DCHECK_NOT_NULL(page_allocator);
DCHECK(IsAligned(size, page_allocator->AllocatePageSize()));
if (!page_allocator->FreePages(address, size)) {
V8::FatalProcessOutOfMemory(nullptr, "FreePages");
}
}
void ReleasePages(v8::PageAllocator* page_allocator, void* address, size_t size,
size_t new_size) {
DCHECK_NOT_NULL(page_allocator);
DCHECK_LT(new_size, size);
DCHECK(IsAligned(new_size, page_allocator->CommitPageSize()));
CHECK(page_allocator->ReleasePages(address, size, new_size));
}
bool SetPermissions(v8::PageAllocator* page_allocator, void* address,
size_t size, PageAllocator::Permission access) {
DCHECK_NOT_NULL(page_allocator);
return page_allocator->SetPermissions(address, size, access);
}
void OnCriticalMemoryPressure() {
V8::GetCurrentPlatform()->OnCriticalMemoryPressure();
}
VirtualMemory::VirtualMemory() = default;
VirtualMemory::VirtualMemory(v8::PageAllocator* page_allocator, size_t size,
void* hint, size_t alignment, JitPermission jit)
: page_allocator_(page_allocator) {
DCHECK_NOT_NULL(page_allocator);
DCHECK(IsAligned(size, page_allocator_->CommitPageSize()));
size_t page_size = page_allocator_->AllocatePageSize();
alignment = RoundUp(alignment, page_size);
PageAllocator::Permission permissions =
jit == JitPermission::kMapAsJittable
? PageAllocator::kNoAccessWillJitLater
: PageAllocator::kNoAccess;
Address address = reinterpret_cast<Address>(AllocatePages(
page_allocator_, hint, RoundUp(size, page_size), alignment, permissions));
if (address != kNullAddress) {
DCHECK(IsAligned(address, alignment));
region_ = base::AddressRegion(address, size);
}
}
VirtualMemory::~VirtualMemory() {
if (IsReserved()) {
Free();
}
}
void VirtualMemory::Reset() {
page_allocator_ = nullptr;
region_ = base::AddressRegion();
}
bool VirtualMemory::SetPermissions(Address address, size_t size,
PageAllocator::Permission access) {
CHECK(InVM(address, size));
bool result = page_allocator_->SetPermissions(
reinterpret_cast<void*>(address), size, access);
return result;
}
bool VirtualMemory::RecommitPages(Address address, size_t size,
PageAllocator::Permission access) {
CHECK(InVM(address, size));
bool result = page_allocator_->RecommitPages(reinterpret_cast<void*>(address),
size, access);
return result;
}
bool VirtualMemory::DiscardSystemPages(Address address, size_t size) {
CHECK(InVM(address, size));
bool result = page_allocator_->DiscardSystemPages(
reinterpret_cast<void*>(address), size);
DCHECK(result);
return result;
}
size_t VirtualMemory::Release(Address free_start) {
DCHECK(IsReserved());
DCHECK(IsAligned(free_start, page_allocator_->CommitPageSize()));
// Notice: Order is important here. The VirtualMemory object might live
// inside the allocated region.
const size_t old_size = region_.size();
const size_t free_size = old_size - (free_start - region_.begin());
CHECK(InVM(free_start, free_size));
region_.set_size(old_size - free_size);
ReleasePages(page_allocator_, reinterpret_cast<void*>(region_.begin()),
old_size, region_.size());
return free_size;
}
void VirtualMemory::Free() {
DCHECK(IsReserved());
// Notice: Order is important here. The VirtualMemory object might live
// inside the allocated region.
v8::PageAllocator* page_allocator = page_allocator_;
base::AddressRegion region = region_;
Reset();
// FreePages expects size to be aligned to allocation granularity however
// ReleasePages may leave size at only commit granularity. Align it here.
FreePages(page_allocator, reinterpret_cast<void*>(region.begin()),
RoundUp(region.size(), page_allocator->AllocatePageSize()));
}
void VirtualMemory::FreeReadOnly() {
DCHECK(IsReserved());
// The only difference to Free is that it doesn't call Reset which would write
// to the VirtualMemory object.
v8::PageAllocator* page_allocator = page_allocator_;
base::AddressRegion region = region_;
// FreePages expects size to be aligned to allocation granularity however
// ReleasePages may leave size at only commit granularity. Align it here.
FreePages(page_allocator, reinterpret_cast<void*>(region.begin()),
RoundUp(region.size(), page_allocator->AllocatePageSize()));
}
VirtualMemoryCage::VirtualMemoryCage() = default;
VirtualMemoryCage::~VirtualMemoryCage() { Free(); }
VirtualMemoryCage::VirtualMemoryCage(VirtualMemoryCage&& other) V8_NOEXCEPT {
*this = std::move(other);
}
VirtualMemoryCage& VirtualMemoryCage::operator=(VirtualMemoryCage&& other)
V8_NOEXCEPT {
base_ = other.base_;
size_ = other.size_;
page_allocator_ = std::move(other.page_allocator_);
reservation_ = std::move(other.reservation_);
other.base_ = kNullAddress;
other.size_ = 0;
return *this;
}
bool VirtualMemoryCage::InitReservation(
const ReservationParams& params, base::AddressRegion existing_reservation) {
DCHECK(!reservation_.IsReserved());
const size_t allocate_page_size = params.page_allocator->AllocatePageSize();
CHECK(IsAligned(params.reservation_size, allocate_page_size));
CHECK(params.base_alignment == ReservationParams::kAnyBaseAlignment ||
IsAligned(params.base_alignment, allocate_page_size));
if (!existing_reservation.is_empty()) {
CHECK_EQ(existing_reservation.size(), params.reservation_size);
CHECK(params.base_alignment == ReservationParams::kAnyBaseAlignment ||
IsAligned(existing_reservation.begin(), params.base_alignment));
reservation_ =
VirtualMemory(params.page_allocator, existing_reservation.begin(),
existing_reservation.size());
base_ = reservation_.address();
} else {
Address hint = params.requested_start_hint;
// Require the hint to be properly aligned because here it's not clear
// anymore whether it should be rounded up or down.
CHECK(IsAligned(hint, params.base_alignment));
VirtualMemory reservation(params.page_allocator, params.reservation_size,
reinterpret_cast<void*>(hint),
params.base_alignment, params.jit);
// The virtual memory reservation fails only due to OOM.
if (!reservation.IsReserved()) return false;
reservation_ = std::move(reservation);
base_ = reservation_.address();
CHECK_EQ(reservation_.size(), params.reservation_size);
}
CHECK_NE(base_, kNullAddress);
CHECK(IsAligned(base_, params.base_alignment));
const Address allocatable_base = RoundUp(base_, params.page_size);
const size_t allocatable_size = RoundDown(
params.reservation_size - (allocatable_base - base_), params.page_size);
size_ = allocatable_base + allocatable_size - base_;
const base::PageFreeingMode page_freeing_mode =
V8_HEAP_USE_PTHREAD_JIT_WRITE_PROTECT &&
params.jit == JitPermission::kMapAsJittable
// On MacOS on ARM64 ("Apple M1"/Apple Silicon) setting permission to
// none might fail if the pages were allocated with RWX permissions,
// so use kDiscard mode instead.
? base::PageFreeingMode::kDiscard
: base::PageFreeingMode::kMakeInaccessible;
page_allocator_ = std::make_unique<base::BoundedPageAllocator>(
params.page_allocator, allocatable_base, allocatable_size,
params.page_size,
base::PageInitializationMode::kAllocatedPagesCanBeUninitialized,
page_freeing_mode);
return true;
}
void VirtualMemoryCage::Free() {
if (IsReserved()) {
base_ = kNullAddress;
size_ = 0;
page_allocator_.reset();
reservation_.Free();
}
}
} // namespace internal
} // namespace v8