v8/test/cctest/heap/heap-utils.cc
Ulan Degenbaev dfc6b4ddaa [heap] New live byte tracking.
This patch changes how space size and capacity are updated in GC:
- space capacity changes only when a page added/removed from the space.
- space size is reset to zero before sweeping and incremented by
  page->live_bytes_count_ for each to-be-swept page.
- space size is refined after sweeping using the accurate
  page->allocated_bytes counter produces by the sweeper.

Invariants:
1. space.capacity = sum [page.size | for page in space].
2. After marking, before sweeping:
   a) space.size = sum [page.live_bytes_count | for page in space].
3. After sweeping, before marking ends:
   a) space.size = sum [page.allocated_bytes | for page in space].
   b) page.allocated_bytes >= (sum [object.size | for object in page] +
         page.linear_allocation_area).
   c) page.area_size = (page.allocated_bytes + page.wasted_memory +
         sum [free_list_entry.size | for free_list_entry in page].

3.b becomes equality if the mutator is not doing array trimming,
object slack tracking during sweeping.

Bug: chromium:694255
Change-Id: Ic8d16a8171187a113fee2df8bf3c2a4c5e77bc08
Reviewed-on: https://chromium-review.googlesource.com/618889
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47409}
2017-08-17 18:16:33 +00:00

213 lines
8.0 KiB
C++

// Copyright 2016 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 "test/cctest/heap/heap-utils.h"
#include "src/factory.h"
#include "src/heap/heap-inl.h"
#include "src/heap/incremental-marking.h"
#include "src/heap/mark-compact.h"
#include "src/isolate.h"
namespace v8 {
namespace internal {
namespace heap {
void SealCurrentObjects(Heap* heap) {
heap->CollectAllGarbage(Heap::kFinalizeIncrementalMarkingMask,
GarbageCollectionReason::kTesting);
heap->CollectAllGarbage(Heap::kFinalizeIncrementalMarkingMask,
GarbageCollectionReason::kTesting);
heap->mark_compact_collector()->EnsureSweepingCompleted();
heap->old_space()->EmptyAllocationInfo();
for (Page* page : *heap->old_space()) {
page->MarkNeverAllocateForTesting();
}
}
int FixedArrayLenFromSize(int size) {
return (size - FixedArray::kHeaderSize) / kPointerSize;
}
std::vector<Handle<FixedArray>> FillOldSpacePageWithFixedArrays(Heap* heap,
int remainder) {
std::vector<Handle<FixedArray>> handles;
Isolate* isolate = heap->isolate();
const int kArraySize = 128;
const int kArrayLen = heap::FixedArrayLenFromSize(kArraySize);
CHECK_EQ(Page::kAllocatableMemory % kArraySize, 0);
Handle<FixedArray> array;
for (int allocated = 0; allocated != (Page::kAllocatableMemory - remainder);
allocated += array->Size()) {
if (allocated == (Page::kAllocatableMemory - kArraySize)) {
array = isolate->factory()->NewFixedArray(
heap::FixedArrayLenFromSize(kArraySize - remainder), TENURED);
CHECK_EQ(kArraySize - remainder, array->Size());
} else {
array = isolate->factory()->NewFixedArray(kArrayLen, TENURED);
CHECK_EQ(kArraySize, array->Size());
}
if (handles.empty()) {
// Check that allocations started on a new page.
CHECK_EQ(array->address(),
Page::FromAddress(array->address())->area_start());
}
handles.push_back(array);
}
return handles;
}
std::vector<Handle<FixedArray>> CreatePadding(Heap* heap, int padding_size,
PretenureFlag tenure,
int object_size) {
std::vector<Handle<FixedArray>> handles;
Isolate* isolate = heap->isolate();
int allocate_memory;
int length;
int free_memory = padding_size;
if (tenure == i::TENURED) {
heap->old_space()->EmptyAllocationInfo();
int overall_free_memory = static_cast<int>(heap->old_space()->Available());
CHECK(padding_size <= overall_free_memory || overall_free_memory == 0);
} else {
heap->new_space()->DisableInlineAllocationSteps();
int overall_free_memory =
static_cast<int>(*heap->new_space()->allocation_limit_address() -
*heap->new_space()->allocation_top_address());
CHECK(padding_size <= overall_free_memory || overall_free_memory == 0);
}
while (free_memory > 0) {
if (free_memory > object_size) {
allocate_memory = object_size;
length = FixedArrayLenFromSize(allocate_memory);
} else {
allocate_memory = free_memory;
length = FixedArrayLenFromSize(allocate_memory);
if (length <= 0) {
// Not enough room to create another fixed array. Let's create a filler.
if (free_memory > (2 * kPointerSize)) {
heap->CreateFillerObjectAt(
*heap->old_space()->allocation_top_address(), free_memory,
ClearRecordedSlots::kNo);
}
break;
}
}
handles.push_back(isolate->factory()->NewFixedArray(length, tenure));
CHECK((tenure == NOT_TENURED && heap->InNewSpace(*handles.back())) ||
(tenure == TENURED && heap->InOldSpace(*handles.back())));
free_memory -= allocate_memory;
}
return handles;
}
void AllocateAllButNBytes(v8::internal::NewSpace* space, int extra_bytes,
std::vector<Handle<FixedArray>>* out_handles) {
space->DisableInlineAllocationSteps();
int space_remaining = static_cast<int>(*space->allocation_limit_address() -
*space->allocation_top_address());
CHECK(space_remaining >= extra_bytes);
int new_linear_size = space_remaining - extra_bytes;
if (new_linear_size == 0) return;
std::vector<Handle<FixedArray>> handles =
heap::CreatePadding(space->heap(), new_linear_size, i::NOT_TENURED);
if (out_handles != nullptr)
out_handles->insert(out_handles->end(), handles.begin(), handles.end());
}
void FillCurrentPage(v8::internal::NewSpace* space,
std::vector<Handle<FixedArray>>* out_handles) {
heap::AllocateAllButNBytes(space, 0, out_handles);
}
bool FillUpOnePage(v8::internal::NewSpace* space,
std::vector<Handle<FixedArray>>* out_handles) {
space->DisableInlineAllocationSteps();
int space_remaining = static_cast<int>(*space->allocation_limit_address() -
*space->allocation_top_address());
if (space_remaining == 0) return false;
std::vector<Handle<FixedArray>> handles =
heap::CreatePadding(space->heap(), space_remaining, i::NOT_TENURED);
if (out_handles != nullptr)
out_handles->insert(out_handles->end(), handles.begin(), handles.end());
return true;
}
void SimulateFullSpace(v8::internal::NewSpace* space,
std::vector<Handle<FixedArray>>* out_handles) {
heap::FillCurrentPage(space, out_handles);
while (heap::FillUpOnePage(space, out_handles) || space->AddFreshPage()) {
}
}
void SimulateIncrementalMarking(i::Heap* heap, bool force_completion) {
CHECK(FLAG_incremental_marking);
i::IncrementalMarking* marking = heap->incremental_marking();
i::MarkCompactCollector* collector = heap->mark_compact_collector();
if (collector->sweeping_in_progress()) {
collector->EnsureSweepingCompleted();
}
if (marking->IsSweeping()) {
marking->FinalizeSweeping();
}
CHECK(marking->IsMarking() || marking->IsStopped() || marking->IsComplete());
if (marking->IsStopped()) {
heap->StartIncrementalMarking(i::Heap::kNoGCFlags,
i::GarbageCollectionReason::kTesting);
}
CHECK(marking->IsMarking() || marking->IsComplete());
if (!force_completion) return;
while (!marking->IsComplete()) {
marking->Step(i::MB, i::IncrementalMarking::NO_GC_VIA_STACK_GUARD,
i::IncrementalMarking::FORCE_COMPLETION, i::StepOrigin::kV8);
if (marking->IsReadyToOverApproximateWeakClosure()) {
marking->FinalizeIncrementally();
}
}
CHECK(marking->IsComplete());
}
void SimulateFullSpace(v8::internal::PagedSpace* space) {
i::MarkCompactCollector* collector = space->heap()->mark_compact_collector();
if (collector->sweeping_in_progress()) {
collector->EnsureSweepingCompleted();
}
space->EmptyAllocationInfo();
space->ResetFreeList();
}
void AbandonCurrentlyFreeMemory(PagedSpace* space) {
space->EmptyAllocationInfo();
for (Page* page : *space) {
page->MarkNeverAllocateForTesting();
}
}
void GcAndSweep(Heap* heap, AllocationSpace space) {
heap->CollectGarbage(space, GarbageCollectionReason::kTesting);
if (heap->mark_compact_collector()->sweeping_in_progress()) {
heap->mark_compact_collector()->EnsureSweepingCompleted();
}
}
void ForceEvacuationCandidate(Page* page) {
CHECK(FLAG_manual_evacuation_candidates_selection);
page->SetFlag(MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
PagedSpace* space = static_cast<PagedSpace*>(page->owner());
Address top = space->top();
Address limit = space->limit();
if (top < limit && Page::FromAllocationAreaAddress(top) == page) {
// Create filler object to keep page iterable if it was iterable.
int remaining = static_cast<int>(limit - top);
space->heap()->CreateFillerObjectAt(top, remaining,
ClearRecordedSlots::kNo);
space->SetTopAndLimit(nullptr, nullptr);
}
}
} // namespace heap
} // namespace internal
} // namespace v8