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cppgc: Revert diagnosing CHECKs for Persistent

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This CL reverts two diagnosing CLs that introduced same-thread CHECKS,
recovering all introduced performance regressions.

We will try to add less performance-sensitive checks again in a follow
up.

This reverts commit 0c2bbfd5bb.
This reverts commit 6643c05940.

Bug: chromium:1253650, chromium:1243257, chromium:1274201
Change-Id: I96c41c39c4f58b062574fa11c4a2d76ad030bcf7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3315437
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78245}
This commit is contained in:
Michael Lippautz 2021-12-06 13:18:39 +01:00 committed by V8 LUCI CQ
parent 9c75acecc4
commit e4b585eae1
3 changed files with 4 additions and 37 deletions
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6
include/cppgc/internal/persistent-node.h
View File

@ -141,18 +141,18 @@ class V8_EXPORT PersistentRegion final : public PersistentRegionBase {
PersistentRegion& operator=(const PersistentRegion&) = delete;
V8_INLINE PersistentNode* AllocateNode(void* owner, TraceCallback trace) {
CPPGC_CHECK(IsCreationThread());
CPPGC_DCHECK(IsCreationThread());
return PersistentRegionBase::AllocateNode(owner, trace);
}
V8_INLINE void FreeNode(PersistentNode* node) {
CPPGC_CHECK(IsCreationThread());
CPPGC_DCHECK(IsCreationThread());
PersistentRegionBase::FreeNode(node);
}
private:
bool IsCreationThread();
private:
int creation_thread_id_;
};

17
include/cppgc/persistent.h
View File

@ -189,15 +189,6 @@ class BasicPersistent final : public PersistentBase,
// heterogeneous assignments between different Member and Persistent handles
// based on their actual types.
V8_CLANG_NO_SANITIZE("cfi-unrelated-cast") T* Get() const {
// TODO(chromium:1253650): Temporary CHECK to diagnose issues.
if (IsValid()) {
CPPGC_CHECK(
WeaknessPolicy::GetPersistentRegion(GetValue()).IsCreationThread());
CPPGC_CHECK(GetNode() != nullptr);
} else {
CPPGC_CHECK(GetNode() == nullptr);
}
// The const_cast below removes the constness from PersistentBase storage.
// The following static_cast re-adds any constness if specified through the
// user-visible template parameter T.
@ -205,14 +196,6 @@ class BasicPersistent final : public PersistentBase,
}
void Clear() {
// TODO(chromium:1253650): Temporary CHECK to diagnose issues.
if (IsValid()) {
CPPGC_CHECK(
WeaknessPolicy::GetPersistentRegion(GetValue()).IsCreationThread());
CPPGC_CHECK(GetNode() != nullptr);
} else {
CPPGC_CHECK(GetNode() == nullptr);
}
// Simplified version of `Assign()` to allow calling without a complete type
// `T`.
if (IsValid()) {

18
src/heap/cppgc/persistent-node.cc
View File

@ -103,19 +103,6 @@ void PersistentRegionBase::Trace(Visitor* visitor) {
nodes_.end());
}
namespace {
thread_local int thread_id = 0;
int GetCurrentThreadId() {
if (thread_id == 0) {
thread_id = v8::base::OS::GetCurrentThreadId();
}
return thread_id;
}
} // namespace
PersistentRegion::PersistentRegion(const FatalOutOfMemoryHandler& oom_handler)
: PersistentRegionBase(oom_handler),
creation_thread_id_(v8::base::OS::GetCurrentThreadId()) {
@ -123,10 +110,7 @@ PersistentRegion::PersistentRegion(const FatalOutOfMemoryHandler& oom_handler)
}
bool PersistentRegion::IsCreationThread() {
// Short circuit using TLS cache. If that doesn't work (e.g. in TLS teardown)
// fall back to the more expensive call in base.
return creation_thread_id_ == GetCurrentThreadId() ||
creation_thread_id_ == v8::base::OS::GetCurrentThreadId();
return creation_thread_id_ == v8::base::OS::GetCurrentThreadId();
}
PersistentRegionLock::PersistentRegionLock() {