github/electron
1
1
Fork 0
mirror of https://github.com/electron/electron.git synced 2026-04-10 03:01:51 -04:00
Code Issues Packages Projects Releases Wiki Activity

chore: cherry-pick 5c4acf2ae64a from v8 (#31229)

Browse Source 
* chore: cherry-pick 5c4acf2ae64a from v8

* chore: update patches

Co-authored-by: PatchUp <73610968+patchup[bot]@users.noreply.github.com>
This commit is contained in:
Pedro Pontes
2021-10-04 08:41:27 +02:00
committed by GitHub
parent 5c5ccfd178
commit f5e1934fb6
2 changed files with 320 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
patches/v8/.patches
View File

@@ -30,3 +30,4 @@ cherry-pick-1234770.patch
cherry-pick-1234764.patch
cherry-pick-fbfd2557c2ab.patch
cherry-pick-034c2003be31.patch
cherry-pick-5c4acf2ae64a.patch

319
patches/v8/cherry-pick-5c4acf2ae64a.patch Normal file
View File

@@ -0,0 +1,319 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Adam Klein <adamk@chromium.org>
Date: Wed, 29 Sep 2021 14:56:46 -0700
Subject: Merged: [heap] Improve ephemeron processing
Revision: 1054ee7f349d6be22e9518cf9b794b206d0e5818
Bug: chromium:1252918
Change-Id: I0764cb78d4a0d4b5859c0edf383c2827321db398
No-Try: true
No-Presubmit: true
No-Tree-Checks: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3195062
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/branch-heads/9.4@{#37}
Cr-Branched-From: 3b51863bc25492549a8bf96ff67ce481b1a3337b-refs/heads/9.4.146@{#1}
Cr-Branched-From: 2890419fc8fb9bdb507fdd801d76fa7dd9f022b5-refs/heads/master@{#76233}
diff --git a/src/heap/concurrent-marking.cc b/src/heap/concurrent-marking.cc
index 9377dad3e4b9fa313c83ffc0128c39d698d741e5..5aa1eef8abe0dfd250655b92a63c925f5f42462c 100644
--- a/src/heap/concurrent-marking.cc
+++ b/src/heap/concurrent-marking.cc
@@ -426,7 +426,7 @@ void ConcurrentMarking::Run(JobDelegate* delegate,
isolate->PrintWithTimestamp("Starting concurrent marking task %d\n",
task_id);
}
- bool ephemeron_marked = false;
+ bool another_ephemeron_iteration = false;
{
TimedScope scope(&time_ms);
@@ -436,7 +436,7 @@ void ConcurrentMarking::Run(JobDelegate* delegate,
while (weak_objects_->current_ephemerons.Pop(task_id, &ephemeron)) {
if (visitor.ProcessEphemeron(ephemeron.key, ephemeron.value)) {
- ephemeron_marked = true;
+ another_ephemeron_iteration = true;
}
}
}
@@ -477,6 +477,7 @@ void ConcurrentMarking::Run(JobDelegate* delegate,
current_marked_bytes += visited_size;
}
}
+ if (objects_processed > 0) another_ephemeron_iteration = true;
marked_bytes += current_marked_bytes;
base::AsAtomicWord::Relaxed_Store<size_t>(&task_state->marked_bytes,
marked_bytes);
@@ -492,7 +493,7 @@ void ConcurrentMarking::Run(JobDelegate* delegate,
while (weak_objects_->discovered_ephemerons.Pop(task_id, &ephemeron)) {
if (visitor.ProcessEphemeron(ephemeron.key, ephemeron.value)) {
- ephemeron_marked = true;
+ another_ephemeron_iteration = true;
}
}
}
@@ -512,8 +513,8 @@ void ConcurrentMarking::Run(JobDelegate* delegate,
base::AsAtomicWord::Relaxed_Store<size_t>(&task_state->marked_bytes, 0);
total_marked_bytes_ += marked_bytes;
- if (ephemeron_marked) {
- set_ephemeron_marked(true);
+ if (another_ephemeron_iteration) {
+ set_another_ephemeron_iteration(true);
}
}
if (FLAG_trace_concurrent_marking) {
diff --git a/src/heap/concurrent-marking.h b/src/heap/concurrent-marking.h
index c685f5cca6de44ca910c5b19c7dce4aa7412e845..54f6057f58b12354629126380452c29c5427c695 100644
--- a/src/heap/concurrent-marking.h
+++ b/src/heap/concurrent-marking.h
@@ -91,10 +91,12 @@ class V8_EXPORT_PRIVATE ConcurrentMarking {
size_t TotalMarkedBytes();
- void set_ephemeron_marked(bool ephemeron_marked) {
- ephemeron_marked_.store(ephemeron_marked);
+ void set_another_ephemeron_iteration(bool another_ephemeron_iteration) {
+ another_ephemeron_iteration_.store(another_ephemeron_iteration);
+ }
+ bool another_ephemeron_iteration() {
+ return another_ephemeron_iteration_.load();
}
- bool ephemeron_marked() { return ephemeron_marked_.load(); }
private:
struct TaskState {
@@ -115,7 +117,7 @@ class V8_EXPORT_PRIVATE ConcurrentMarking {
WeakObjects* const weak_objects_;
TaskState task_state_[kMaxTasks + 1];
std::atomic<size_t> total_marked_bytes_{0};
- std::atomic<bool> ephemeron_marked_{false};
+ std::atomic<bool> another_ephemeron_iteration_{false};
};
} // namespace internal
diff --git a/src/heap/incremental-marking.cc b/src/heap/incremental-marking.cc
index 7b6b01855d608f6dca506bb91b181525b0394e26..6104f2146c4c91d7e3d92698189db5dc3103ecb3 100644
--- a/src/heap/incremental-marking.cc
+++ b/src/heap/incremental-marking.cc
@@ -927,7 +927,8 @@ StepResult IncrementalMarking::Step(double max_step_size_in_ms,
// This ignores that case where the embedder finds new V8-side objects. The
// assumption is that large graphs are well connected and can mostly be
// processed on their own. For small graphs, helping is not necessary.
- v8_bytes_processed = collector_->ProcessMarkingWorklist(bytes_to_process);
+ std::tie(v8_bytes_processed, std::ignore) =
+ collector_->ProcessMarkingWorklist(bytes_to_process);
StepResult v8_result = local_marking_worklists()->IsEmpty()
? StepResult::kNoImmediateWork
: StepResult::kMoreWorkRemaining;
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index 780d3dc6ca7a936080f817342c066db604b89303..f4e8356823131b4ac39ef37e580dd46cceac30ef 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -1604,24 +1604,24 @@ void MarkCompactCollector::MarkDescriptorArrayFromWriteBarrier(
descriptors, number_of_own_descriptors);
}
-void MarkCompactCollector::ProcessEphemeronsUntilFixpoint() {
- bool work_to_do = true;
+bool MarkCompactCollector::ProcessEphemeronsUntilFixpoint() {
int iterations = 0;
int max_iterations = FLAG_ephemeron_fixpoint_iterations;
- while (work_to_do) {
+ bool another_ephemeron_iteration_main_thread;
+
+ do {
PerformWrapperTracing();
if (iterations >= max_iterations) {
// Give up fixpoint iteration and switch to linear algorithm.
- ProcessEphemeronsLinear();
- break;
+ return false;
}
// Move ephemerons from next_ephemerons into current_ephemerons to
// drain them in this iteration.
weak_objects_.current_ephemerons.Swap(weak_objects_.next_ephemerons);
- heap()->concurrent_marking()->set_ephemeron_marked(false);
+ heap()->concurrent_marking()->set_another_ephemeron_iteration(false);
{
TRACE_GC(heap()->tracer(),
@@ -1632,47 +1632,54 @@ void MarkCompactCollector::ProcessEphemeronsUntilFixpoint() {
TaskPriority::kUserBlocking);
}
- work_to_do = ProcessEphemerons();
+ another_ephemeron_iteration_main_thread = ProcessEphemerons();
FinishConcurrentMarking();
}
CHECK(weak_objects_.current_ephemerons.IsEmpty());
CHECK(weak_objects_.discovered_ephemerons.IsEmpty());
- work_to_do = work_to_do || !local_marking_worklists()->IsEmpty() ||
- heap()->concurrent_marking()->ephemeron_marked() ||
- !local_marking_worklists()->IsEmbedderEmpty() ||
- !heap()->local_embedder_heap_tracer()->IsRemoteTracingDone();
++iterations;
- }
+ } while (another_ephemeron_iteration_main_thread ||
+ heap()->concurrent_marking()->another_ephemeron_iteration() ||
+ !local_marking_worklists()->IsEmpty() ||
+ !local_marking_worklists()->IsEmbedderEmpty() ||
+ !heap()->local_embedder_heap_tracer()->IsRemoteTracingDone());
CHECK(local_marking_worklists()->IsEmpty());
CHECK(weak_objects_.current_ephemerons.IsEmpty());
CHECK(weak_objects_.discovered_ephemerons.IsEmpty());
+ return true;
}
bool MarkCompactCollector::ProcessEphemerons() {
Ephemeron ephemeron;
- bool ephemeron_marked = false;
+ bool another_ephemeron_iteration = false;
// Drain current_ephemerons and push ephemerons where key and value are still
// unreachable into next_ephemerons.
while (weak_objects_.current_ephemerons.Pop(kMainThreadTask, &ephemeron)) {
if (ProcessEphemeron(ephemeron.key, ephemeron.value)) {
- ephemeron_marked = true;
+ another_ephemeron_iteration = true;
}
}
// Drain marking worklist and push discovered ephemerons into
// discovered_ephemerons.
- DrainMarkingWorklist();
+ size_t objects_processed;
+ std::tie(std::ignore, objects_processed) = ProcessMarkingWorklist(0);
+
+ // As soon as a single object was processed and potentially marked another
+ // object we need another iteration. Otherwise we might miss to apply
+ // ephemeron semantics on it.
+ if (objects_processed > 0) another_ephemeron_iteration = true;
// Drain discovered_ephemerons (filled in the drain MarkingWorklist-phase
// before) and push ephemerons where key and value are still unreachable into
// next_ephemerons.
while (weak_objects_.discovered_ephemerons.Pop(kMainThreadTask, &ephemeron)) {
if (ProcessEphemeron(ephemeron.key, ephemeron.value)) {
- ephemeron_marked = true;
+ another_ephemeron_iteration = true;
}
}
@@ -1680,7 +1687,7 @@ bool MarkCompactCollector::ProcessEphemerons() {
weak_objects_.ephemeron_hash_tables.FlushToGlobal(kMainThreadTask);
weak_objects_.next_ephemerons.FlushToGlobal(kMainThreadTask);
- return ephemeron_marked;
+ return another_ephemeron_iteration;
}
void MarkCompactCollector::ProcessEphemeronsLinear() {
@@ -1766,6 +1773,12 @@ void MarkCompactCollector::ProcessEphemeronsLinear() {
ephemeron_marking_.newly_discovered.shrink_to_fit();
CHECK(local_marking_worklists()->IsEmpty());
+ CHECK(weak_objects_.current_ephemerons.IsEmpty());
+ CHECK(weak_objects_.discovered_ephemerons.IsEmpty());
+
+ // Flush local ephemerons for main task to global pool.
+ weak_objects_.ephemeron_hash_tables.FlushToGlobal(kMainThreadTask);
+ weak_objects_.next_ephemerons.FlushToGlobal(kMainThreadTask);
}
void MarkCompactCollector::PerformWrapperTracing() {
@@ -1787,9 +1800,11 @@ void MarkCompactCollector::PerformWrapperTracing() {
void MarkCompactCollector::DrainMarkingWorklist() { ProcessMarkingWorklist(0); }
template <MarkCompactCollector::MarkingWorklistProcessingMode mode>
-size_t MarkCompactCollector::ProcessMarkingWorklist(size_t bytes_to_process) {
+std::pair<size_t, size_t> MarkCompactCollector::ProcessMarkingWorklist(
+ size_t bytes_to_process) {
HeapObject object;
size_t bytes_processed = 0;
+ size_t objects_processed = 0;
bool is_per_context_mode = local_marking_worklists()->IsPerContextMode();
Isolate* isolate = heap()->isolate();
while (local_marking_worklists()->Pop(&object) ||
@@ -1829,18 +1844,19 @@ size_t MarkCompactCollector::ProcessMarkingWorklist(size_t bytes_to_process) {
map, object, visited_size);
}
bytes_processed += visited_size;
+ objects_processed++;
if (bytes_to_process && bytes_processed >= bytes_to_process) {
break;
}
}
- return bytes_processed;
+ return std::make_pair(bytes_processed, objects_processed);
}
// Generate definitions for use in other files.
-template size_t MarkCompactCollector::ProcessMarkingWorklist<
+template std::pair<size_t, size_t> MarkCompactCollector::ProcessMarkingWorklist<
MarkCompactCollector::MarkingWorklistProcessingMode::kDefault>(
size_t bytes_to_process);
-template size_t MarkCompactCollector::ProcessMarkingWorklist<
+template std::pair<size_t, size_t> MarkCompactCollector::ProcessMarkingWorklist<
MarkCompactCollector::MarkingWorklistProcessingMode::
kTrackNewlyDiscoveredObjects>(size_t bytes_to_process);
@@ -1865,7 +1881,23 @@ void MarkCompactCollector::ProcessEphemeronMarking() {
// buffer, flush it into global pool.
weak_objects_.next_ephemerons.FlushToGlobal(kMainThreadTask);
- ProcessEphemeronsUntilFixpoint();
+ if (!ProcessEphemeronsUntilFixpoint()) {
+ // Fixpoint iteration needed too many iterations and was cancelled. Use the
+ // guaranteed linear algorithm.
+ ProcessEphemeronsLinear();
+ }
+
+#ifdef VERIFY_HEAP
+ if (FLAG_verify_heap) {
+ Ephemeron ephemeron;
+
+ weak_objects_.current_ephemerons.Swap(weak_objects_.next_ephemerons);
+
+ while (weak_objects_.current_ephemerons.Pop(kMainThreadTask, &ephemeron)) {
+ CHECK(!ProcessEphemeron(ephemeron.key, ephemeron.value));
+ }
+ }
+#endif
CHECK(local_marking_worklists()->IsEmpty());
CHECK(heap()->local_embedder_heap_tracer()->IsRemoteTracingDone());
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 08d9a5bcb6b444f3ce0f7c66f5be8df9bdd5324e..fbdb74c30c19cae1d0a568178d15666ec9318cc9 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -590,7 +590,7 @@ class MarkCompactCollector final : public MarkCompactCollectorBase {
// is drained until it is empty.
template <MarkingWorklistProcessingMode mode =
MarkingWorklistProcessingMode::kDefault>
- size_t ProcessMarkingWorklist(size_t bytes_to_process);
+ std::pair<size_t, size_t> ProcessMarkingWorklist(size_t bytes_to_process);
private:
void ComputeEvacuationHeuristics(size_t area_size,
@@ -636,8 +636,9 @@ class MarkCompactCollector final : public MarkCompactCollectorBase {
bool ProcessEphemeron(HeapObject key, HeapObject value);
// Marks ephemerons and drains marking worklist iteratively
- // until a fixpoint is reached.
- void ProcessEphemeronsUntilFixpoint();
+ // until a fixpoint is reached. Returns false if too many iterations have been
+ // tried and the linear approach should be used.
+ bool ProcessEphemeronsUntilFixpoint();
// Drains ephemeron and marking worklists. Single iteration of the
// fixpoint iteration.