v8/test/unittests/heap/local-heap-unittest.cc
Dominik Inführ 93f28d16c7 Reland "[heap] Optimize time to reach global safepoint"
This is a reland of 86038ecfdc

Compared to the previous CL this one is adding a TSAN suppression
for GlobalSafepoint::EnterSafepointScope. local_heaps_mutex_ of client
isolates may be locked in any order. This would be detected by TSAN as a
potential race. Add some additional DCHECKs to compensate for that
missing test coverage.

As a cleanup this CL also removes the unused methods ContainsLocalHeap()
and ContainsAnyLocalHeap() from LocalHeap.

Original change's description:
> [heap] Optimize time to reach global safepoint
>
> Initial support for global safepoints kept it simple by entering a
> safepoint for each of them one after another. This means
> time-to-global-safepoint is the sum of all time-to-safepoint operations.
> We can improve this slightly by splitting up the safepoint iteration
> into two operations:
>
> 1) Initiate safepoint lock (locks local_heaps_mutex_, arms the barrier
>    and sets SafepointRequested flag for all client threads)
> 2) Block until all runnning client threads reach a safepoint
>
> We now perform operation 1) for all clients first and only then start
> with operation 2).
>
> Bug: v8:11708
> Change-Id: Iaafd3c6d70bcf7026f722633e9250b04148b3da6
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3310910
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#78308}

Bug: v8:11708, v8:12492
Change-Id: I7087ba23c08f2d4edb9b632eef3c218fc76342e7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3328786
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78583}
2022-01-12 10:35:25 +00:00

197 lines
5.0 KiB
C++

// Copyright 2020 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/heap/local-heap.h"
#include "src/base/platform/condition-variable.h"
#include "src/base/platform/mutex.h"
#include "src/heap/heap.h"
#include "src/heap/parked-scope.h"
#include "src/heap/safepoint.h"
#include "test/unittests/test-utils.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace v8 {
namespace internal {
using LocalHeapTest = TestWithIsolate;
TEST_F(LocalHeapTest, Initialize) {
Heap* heap = i_isolate()->heap();
heap->safepoint()->AssertMainThreadIsOnlyThread();
}
TEST_F(LocalHeapTest, Current) {
Heap* heap = i_isolate()->heap();
CHECK_NULL(LocalHeap::Current());
{
LocalHeap lh(heap, ThreadKind::kMain);
lh.SetUpMainThreadForTesting();
CHECK_NULL(LocalHeap::Current());
}
CHECK_NULL(LocalHeap::Current());
{
LocalHeap lh(heap, ThreadKind::kMain);
lh.SetUpMainThreadForTesting();
CHECK_NULL(LocalHeap::Current());
}
CHECK_NULL(LocalHeap::Current());
}
namespace {
class BackgroundThread final : public v8::base::Thread {
public:
explicit BackgroundThread(Heap* heap)
: v8::base::Thread(base::Thread::Options("BackgroundThread")),
heap_(heap) {}
void Run() override {
CHECK_NULL(LocalHeap::Current());
{
LocalHeap lh(heap_, ThreadKind::kBackground);
CHECK_EQ(&lh, LocalHeap::Current());
}
CHECK_NULL(LocalHeap::Current());
}
Heap* heap_;
};
} // anonymous namespace
TEST_F(LocalHeapTest, CurrentBackground) {
Heap* heap = i_isolate()->heap();
CHECK_NULL(LocalHeap::Current());
{
LocalHeap lh(heap, ThreadKind::kMain);
lh.SetUpMainThreadForTesting();
auto thread = std::make_unique<BackgroundThread>(heap);
CHECK(thread->Start());
CHECK_NULL(LocalHeap::Current());
thread->Join();
CHECK_NULL(LocalHeap::Current());
}
CHECK_NULL(LocalHeap::Current());
}
namespace {
class GCEpilogue {
public:
static void Callback(void* data) {
reinterpret_cast<GCEpilogue*>(data)->was_invoked_ = true;
}
void NotifyStarted() {
base::LockGuard<base::Mutex> lock_guard(&mutex_);
started_ = true;
cv_.NotifyOne();
}
void WaitUntilStarted() {
base::LockGuard<base::Mutex> lock_guard(&mutex_);
while (!started_) {
cv_.Wait(&mutex_);
}
}
void RequestStop() {
base::LockGuard<base::Mutex> lock_guard(&mutex_);
stop_requested_ = true;
}
bool StopRequested() {
base::LockGuard<base::Mutex> lock_guard(&mutex_);
return stop_requested_;
}
bool WasInvoked() { return was_invoked_; }
private:
bool was_invoked_ = false;
bool started_ = false;
bool stop_requested_ = false;
base::Mutex mutex_;
base::ConditionVariable cv_;
};
class BackgroundThreadForGCEpilogue final : public v8::base::Thread {
public:
explicit BackgroundThreadForGCEpilogue(Heap* heap, bool parked,
GCEpilogue* epilogue)
: v8::base::Thread(base::Thread::Options("BackgroundThread")),
heap_(heap),
parked_(parked),
epilogue_(epilogue) {}
void Run() override {
LocalHeap lh(heap_, ThreadKind::kBackground);
base::Optional<UnparkedScope> unparked_scope;
if (!parked_) {
unparked_scope.emplace(&lh);
}
{
base::Optional<UnparkedScope> nested_unparked_scope;
if (parked_) nested_unparked_scope.emplace(&lh);
lh.AddGCEpilogueCallback(&GCEpilogue::Callback, epilogue_);
}
epilogue_->NotifyStarted();
while (!epilogue_->StopRequested()) {
lh.Safepoint();
}
{
base::Optional<UnparkedScope> nested_unparked_scope;
if (parked_) nested_unparked_scope.emplace(&lh);
lh.RemoveGCEpilogueCallback(&GCEpilogue::Callback, epilogue_);
}
}
Heap* heap_;
bool parked_;
GCEpilogue* epilogue_;
};
} // anonymous namespace
TEST_F(LocalHeapTest, GCEpilogue) {
Heap* heap = i_isolate()->heap();
LocalHeap lh(heap, ThreadKind::kMain);
lh.SetUpMainThreadForTesting();
std::array<GCEpilogue, 3> epilogue;
{
UnparkedScope unparked(&lh);
lh.AddGCEpilogueCallback(&GCEpilogue::Callback, &epilogue[0]);
}
auto thread1 =
std::make_unique<BackgroundThreadForGCEpilogue>(heap, true, &epilogue[1]);
auto thread2 = std::make_unique<BackgroundThreadForGCEpilogue>(heap, false,
&epilogue[2]);
CHECK(thread1->Start());
CHECK(thread2->Start());
epilogue[1].WaitUntilStarted();
epilogue[2].WaitUntilStarted();
{
UnparkedScope scope(&lh);
heap->PreciseCollectAllGarbage(Heap::kNoGCFlags,
GarbageCollectionReason::kTesting);
}
epilogue[1].RequestStop();
epilogue[2].RequestStop();
thread1->Join();
thread2->Join();
{
UnparkedScope unparked(&lh);
lh.RemoveGCEpilogueCallback(&GCEpilogue::Callback, &epilogue[0]);
}
for (auto& e : epilogue) {
CHECK(e.WasInvoked());
}
}
} // namespace internal
} // namespace v8