Add memory pressure notification API

src/heap/heap.cc

 // Copyright 2012 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/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 50 matching lines @@
       : AllocationObserver(step_size), heap_(heap) {}
 
   void Step(int bytes_allocated, Address, size_t) override {
     heap_.ScheduleIdleScavengeIfNeeded(bytes_allocated);
   }
 
  private:
   Heap& heap_;
 };
 
-
 Heap::Heap()
     : amount_of_external_allocated_memory_(0),
       amount_of_external_allocated_memory_at_last_global_gc_(0),
       isolate_(NULL),
       code_range_size_(0),
       // semispace_size_ should be a power of 2 and old_generation_size_ should
       // be a multiple of Page::kPageSize.
       reserved_semispace_size_(8 * (kPointerSize / 4) * MB),
       max_semi_space_size_(8 * (kPointerSize / 4) * MB),
       initial_semispace_size_(Page::kPageSize),
       max_old_generation_size_(700ul * (kPointerSize / 4) * MB),
       initial_old_generation_size_(max_old_generation_size_ /
                                    kInitalOldGenerationLimitFactor),
       old_generation_size_configured_(false),
       max_executable_size_(256ul * (kPointerSize / 4) * MB),
       // Variables set based on semispace_size_ and old_generation_size_ in
       // ConfigureHeap.
       // Will be 4 * reserved_semispace_size_ to ensure that young
       // generation can be aligned to its size.
       maximum_committed_(0),
       survived_since_last_expansion_(0),
       survived_last_scavenge_(0),
       always_allocate_scope_count_(0),
+      memory_pressure_level_(MemoryPressureLevel::kNone),
       contexts_disposed_(0),
       number_of_disposed_maps_(0),
       global_ic_age_(0),
       new_space_(this),
       old_space_(NULL),
       code_space_(NULL),
       map_space_(NULL),
       lo_space_(NULL),
       gc_state_(NOT_IN_GC),
       gc_post_processing_depth_(0),
@@ skipping 678 matching lines @@
   ~GCCallbacksScope() { heap_->gc_callbacks_depth_--; }
 
   bool CheckReenter() { return heap_->gc_callbacks_depth_ == 1; }
 
  private:
   Heap* heap_;
 };
 
 
 void Heap::HandleGCRequest() {
-  if (incremental_marking()->request_type() ==
-      IncrementalMarking::COMPLETE_MARKING) {
+  if (HighMemoryPressure()) {
+    incremental_marking()->reset_request_type();
+    CheckMemoryPressure();
+  } else if (incremental_marking()->request_type() ==
+             IncrementalMarking::COMPLETE_MARKING) {
+    incremental_marking()->reset_request_type();
     CollectAllGarbage(current_gc_flags_, "GC interrupt",
                       current_gc_callback_flags_);
-  } else if (incremental_marking()->IsMarking() &&
+  } else if (incremental_marking()->request_type() ==
+                 IncrementalMarking::FINALIZATION &&
+             incremental_marking()->IsMarking() &&
              !incremental_marking()->finalize_marking_completed()) {
+    incremental_marking()->reset_request_type();
     FinalizeIncrementalMarking("GC interrupt: finalize incremental marking");
   }
 }
 
 
 void Heap::ScheduleIdleScavengeIfNeeded(int bytes_allocated) {
   scavenge_job_->ScheduleIdleTaskIfNeeded(this, bytes_allocated);
 }
 
 
@@ skipping 220 matching lines @@
       // - this GC decreased committed memory,
       // - there is high fragmentation,
       // - there are live detached contexts.
       event.next_gc_likely_to_collect_more =
           (committed_memory_before - committed_memory_after) > MB ||
           HasHighFragmentation(used_memory_after, committed_memory_after) ||
           (detached_contexts()->length() > 0);
       if (deserialization_complete_) {
         memory_reducer_->NotifyMarkCompact(event);
       }
+      memory_pressure_level_.SetValue(MemoryPressureLevel::kNone);
     }
 
     tracer()->Stop(collector);
   }
 
   if (collector == MARK_COMPACTOR &&
       (gc_callback_flags & (kGCCallbackFlagForced |
                             kGCCallbackFlagCollectAllAvailableGarbage)) != 0) {
     isolate()->CountUsage(v8::Isolate::kForcedGC);
   }
@@ skipping 399 matching lines @@
 
 
 void Heap::MarkCompactEpilogue() {
   gc_state_ = NOT_IN_GC;
 
   isolate_->counters()->objs_since_last_full()->Set(0);
 
   incremental_marking()->Epilogue();
 
   PreprocessStackTraces();
-
   DCHECK(incremental_marking()->IsStopped());
 
   // We finished a marking cycle. We can uncommit the marking deque until
   // we start marking again.
   mark_compact_collector()->marking_deque()->Uninitialize();
   mark_compact_collector()->EnsureMarkingDequeIsCommitted(
       MarkCompactCollector::kMinMarkingDequeSize);
 }
 
 
@@ skipping 2947 matching lines @@
   return result;
 }
 
 
 bool Heap::RecentIdleNotificationHappened() {
   return (last_idle_notification_time_ +
           GCIdleTimeHandler::kMaxScheduledIdleTime) >
          MonotonicallyIncreasingTimeInMs();
 }
 
+class MemoryPressureInterruptTask : public CancelableTask {
+ public:
+  explicit MemoryPressureInterruptTask(Heap* heap)
+      : CancelableTask(heap->isolate()), heap_(heap) {}
+
+  virtual ~MemoryPressureInterruptTask() {}
+
+ private:
+  // v8::internal::CancelableTask overrides.
+  void RunInternal() override { heap_->CheckMemoryPressure(); }
+
+  Heap* heap_;
+  DISALLOW_COPY_AND_ASSIGN(MemoryPressureInterruptTask);
+};
+
+void Heap::CheckMemoryPressure() {
+  if (memory_pressure_level_.Value() == MemoryPressureLevel::kCritical) {
+    CollectGarbageOnMemoryPressure("memory pressure");
+  } else if (memory_pressure_level_.Value() == MemoryPressureLevel::kModerate) {
+    if (FLAG_incremental_marking && incremental_marking()->IsStopped()) {
+      StartIdleIncrementalMarking();
+    }
+  }
+  MemoryReducer::Event event;
+  event.type = MemoryReducer::kPossibleGarbage;
+  event.time_ms = MonotonicallyIncreasingTimeInMs();
+  memory_reducer_->NotifyPossibleGarbage(event);
+}
+
+void Heap::CollectGarbageOnMemoryPressure(const char* source) {
+  CollectAllGarbage(kReduceMemoryFootprintMask | kAbortIncrementalMarkingMask,
+                    source);
+}
+
+void Heap::MemoryPressureNotification(MemoryPressureLevel level,
+                                      bool is_isolate_locked) {
+  MemoryPressureLevel previous = memory_pressure_level_.Value();
+  memory_pressure_level_.SetValue(level);
+  if ((previous != MemoryPressureLevel::kCritical &&
+       level == MemoryPressureLevel::kCritical) ||
+      (previous == MemoryPressureLevel::kNone &&
+       level == MemoryPressureLevel::kModerate)) {
+    if (is_isolate_locked) {
+      CheckMemoryPressure();
+    } else {
+      ExecutionAccess access(isolate());
+      isolate()->stack_guard()->RequestGC();
+      V8::GetCurrentPlatform()->CallOnForegroundThread(
+          reinterpret_cast<v8::Isolate*>(isolate()),
+          new MemoryPressureInterruptTask(this));
+    }
+  }
+}
 
 #ifdef DEBUG
 
 void Heap::Print() {
   if (!HasBeenSetUp()) return;
   isolate()->PrintStack(stdout);
   AllSpaces spaces(this);
   for (Space* space = spaces.next(); space != NULL; space = spaces.next()) {
     space->Print();
   }
@@ skipping 1977 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8