AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Remove GC post-processing check from externalizing strings

Browse Source 
This check was probably relevant in the past (when GC was different),
but it is unknown today why it exists. It can cause races in a
concurrent set-up though, as tracking the post-processing state is not
atomic.
Due to possible races and no reason to check whether we are in GC
post-processing phase, this check is removed from
String::SupportsExternalization().

SupportsExternalization() was the only user of the logic.

Drive-by: Remove tracking of GC post-processing state, as
Change-Id: Id0a6dd25a8dc6044504b40f1c754612dedcacf75
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4147612
Auto-Submit: Patrick Thier <pthier@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#85167}
This commit is contained in:
pthier 2023-01-09 15:38:21 +01:00 committed by V8 LUCI CQ
parent 499697b157
commit 69df64a75c
3 changed files with 1 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/heap/heap.cc
View File

@ -1777,14 +1777,12 @@ bool Heap::CollectGarbage(AllocationSpace space,
{
TRACE_GC(tracer(), GCTracer::Scope::HEAP_EXTERNAL_WEAK_GLOBAL_HANDLES);
gc_post_processing_depth_++;
{
AllowGarbageCollection allow_gc;
AllowJavascriptExecution allow_js(isolate());
isolate_->global_handles()->PostGarbageCollectionProcessing(
collector, gc_callback_flags);
}
gc_post_processing_depth_--;
}
{

4
src/heap/heap.h
View File

@ -661,8 +661,6 @@ class Heap {
return ignore_local_gc_requests_depth_ > 0;
}
inline bool IsInGCPostProcessing() { return gc_post_processing_depth_ > 0; }
bool IsGCWithStack() const;
// Performs GC after background allocation failure.
@ -2206,8 +2204,6 @@ class Heap {
std::atomic<HeapState> gc_state_{NOT_IN_GC};
int gc_post_processing_depth_ = 0;
// Returns the amount of external memory registered since last global gc.
V8_EXPORT_PRIVATE uint64_t AllocatedExternalMemorySinceMarkCompact();

3
src/objects/string.cc
View File

@ -620,8 +620,7 @@ bool String::SupportsExternalization() {
DCHECK_LE(ExternalString::kUncachedSize, this->Size());
#endif
Isolate* isolate = GetIsolateFromWritableObject(*this);
return !isolate->heap()->IsInGCPostProcessing();
return true;
}
const char* String::PrefixForDebugPrint() const {