Reviewers: Michael Lippautz,
Description:
Concurrently unmap free pages.
BUG=
Please review this at https://codereview.chromium.org/1303263002/
Base URL: https://chromium.googlesource.com/v8/v8.git@master
Affected files (+56, -5 lines):
M src/heap/heap.h
M src/heap/heap.cc
M src/heap/mark-compact.cc
Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index
234bc9f563a14d148cc19967d902fb7cc1c4ff8e..0ee13ebaf4d814b5b83c7a7ac7c42a6085cc7b10
100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -135,6 +135,7 @@ Heap::Heap()
current_gc_flags_(Heap::kNoGCFlags),
external_string_table_(this),
chunks_queued_for_free_(NULL),
+ pending_unmap_job_semaphore_(0),
gc_callbacks_depth_(0),
deserialization_complete_(false),
concurrent_sweeping_enabled_(false),
@@ -6654,6 +6655,34 @@ void ExternalStringTable::TearDown() {
}
+class Heap::UnmapFreeMemoryTask : public v8::Task {
+ public:
+ UnmapFreeMemoryTask(Heap* heap, MemoryChunk* head)
+ : heap_(heap), head_(head) {}
+ virtual ~UnmapFreeMemoryTask() {}
+
+
+ private:
+ // v8::Task overrides.
+ void Run() override {
+ heap_->FreeQueuedChunks(head_);
+ heap_->pending_unmap_job_semaphore_.Signal();
+ }
+
+ Heap* heap_;
+ MemoryChunk* head_;
+
+ DISALLOW_COPY_AND_ASSIGN(UnmapFreeMemoryTask);
+};
+
+
+void Heap::WaitUntilUnmappingOfFreeChunksCompleted() {
+ // We start an unmap job after sweeping and after compaction.
+ pending_unmap_job_semaphore_.Wait();
+ pending_unmap_job_semaphore_.Wait();
+}
+
+
void Heap::QueueMemoryChunkForFree(MemoryChunk* chunk) {
chunk->set_next_chunk(chunks_queued_for_free_);
chunks_queued_for_free_ = chunk;
@@ -6668,19 +6697,32 @@ void
Heap::FilterStoreBufferEntriesOnAboutToBeFreedPages() {
next = chunk->next_chunk();
chunk->SetFlag(MemoryChunk::ABOUT_TO_BE_FREED);
}
- isolate_->heap()->store_buffer()->Compact();
- isolate_->heap()->store_buffer()->Filter(MemoryChunk::ABOUT_TO_BE_FREED);
+ store_buffer()->Compact();
+ store_buffer()->Filter(MemoryChunk::ABOUT_TO_BE_FREED);
}
void Heap::FreeQueuedChunks() {
+ if (chunks_queued_for_free_ != NULL) {
+ V8::GetCurrentPlatform()->CallOnBackgroundThread(
+ new UnmapFreeMemoryTask(this, chunks_queued_for_free_),
+ v8::Platform::kShortRunningTask);
+ chunks_queued_for_free_ = NULL;
+ } else {
+ // If we do not have anything to unmap, we just signal the semaphore
+ // that we are done.
+ pending_unmap_job_semaphore_.Signal();
+ }
+}
+
+
+void Heap::FreeQueuedChunks(MemoryChunk* list_head) {
MemoryChunk* next;
MemoryChunk* chunk;
- for (chunk = chunks_queued_for_free_; chunk != NULL; chunk = next) {
+ for (chunk = list_head; chunk != NULL; chunk = next) {
next = chunk->next_chunk();
isolate_->memory_allocator()->Free(chunk);
}
- chunks_queued_for_free_ = NULL;
}
Index: src/heap/heap.h
diff --git a/src/heap/heap.h b/src/heap/heap.h
index
415e7d0c5ee569ea458263beb294efc1245cead9..88d49cff421d7389d6c7df9c8c9b7787bd32bf17
100644
--- a/src/heap/heap.h
+++ b/src/heap/heap.h
@@ -1442,7 +1442,9 @@ class Heap {
void QueueMemoryChunkForFree(MemoryChunk* chunk);
void FilterStoreBufferEntriesOnAboutToBeFreedPages();
+ void FreeQueuedChunks(MemoryChunk* list_head);
void FreeQueuedChunks();
+ void WaitUntilUnmappingOfFreeChunksCompleted();
int gc_count() const { return gc_count_; }
@@ -1681,6 +1683,8 @@ class Heap {
private:
Heap();
+ class UnmapFreeMemoryTask;
+
int current_gc_flags() { return current_gc_flags_; }
void set_current_gc_flags(int flags) {
current_gc_flags_ = flags;
@@ -2299,6 +2303,8 @@ class Heap {
MemoryChunk* chunks_queued_for_free_;
+ base::Semaphore pending_unmap_job_semaphore_;
+
base::Mutex relocation_mutex_;
int gc_callbacks_depth_;
Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index
af6894c5755b2a6d7a14a853c3d3fd1ddb83de73..4c8db42035bb8c5722fe9b2fbe73b35d87f43f54
100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -519,12 +519,15 @@ void MarkCompactCollector::EnsureSweepingCompleted() {
SweepInParallel(heap()->paged_space(CODE_SPACE), 0);
SweepInParallel(heap()->paged_space(MAP_SPACE), 0);
}
- // Wait twice for both jobs.
+
if (heap()->concurrent_sweeping_enabled()) {
pending_sweeper_jobs_semaphore_.Wait();
pending_sweeper_jobs_semaphore_.Wait();
pending_sweeper_jobs_semaphore_.Wait();
}
+
+ heap()->WaitUntilUnmappingOfFreeChunksCompleted();
+
ParallelSweepSpacesComplete();
sweeping_in_progress_ = false;
RefillFreeList(heap()->paged_space(OLD_SPACE));
--
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
---
You received this message because you are subscribed to the Google Groups "v8-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
