ART: reduce UpdateModUnionTable time for partial GC
UpdateModUnionTable is to scan objects with dirty cards in the immune
region. The immune region of partial GC are image space and zygote
space. As image space is always immuned for any kind of GC, there is no
need to scan dirty cards of zygote space pointing to image space for
partial GC.
Change-Id: I2e1f61c2b361985c211076a441418797abf324c2
diff --git a/runtime/gc/accounting/mod_union_table.cc b/runtime/gc/accounting/mod_union_table.cc
index 0a15e9e..b1ccc0b 100644
--- a/runtime/gc/accounting/mod_union_table.cc
+++ b/runtime/gc/accounting/mod_union_table.cc
@@ -26,6 +26,7 @@
#include "gc/collector/mark_sweep-inl.h"
#include "gc/heap.h"
#include "gc/space/space.h"
+#include "gc/space/image_space.h"
#include "mirror/art_field-inl.h"
#include "mirror/object-inl.h"
#include "mirror/class-inl.h"
@@ -76,8 +77,9 @@
public:
ModUnionUpdateObjectReferencesVisitor(MarkHeapReferenceCallback* callback, void* arg,
space::ContinuousSpace* from_space,
+ space::ImageSpace* image_space,
bool* contains_reference_to_other_space)
- : callback_(callback), arg_(arg), from_space_(from_space),
+ : callback_(callback), arg_(arg), from_space_(from_space), image_space_(image_space),
contains_reference_to_other_space_(contains_reference_to_other_space) {
}
@@ -87,7 +89,7 @@
// Only add the reference if it is non null and fits our criteria.
mirror::HeapReference<Object>* obj_ptr = obj->GetFieldObjectReferenceAddr(offset);
mirror::Object* ref = obj_ptr->AsMirrorPtr();
- if (ref != nullptr && !from_space_->HasAddress(ref)) {
+ if (ref != nullptr && !from_space_->HasAddress(ref) && !image_space_->HasAddress(ref)) {
*contains_reference_to_other_space_ = true;
callback_(obj_ptr, arg_);
}
@@ -98,6 +100,7 @@
void* arg_;
// Space which we are scanning
space::ContinuousSpace* const from_space_;
+ space::ImageSpace* const image_space_;
// Set if we have any references to another space.
bool* const contains_reference_to_other_space_;
};
@@ -105,16 +108,16 @@
class ModUnionScanImageRootVisitor {
public:
ModUnionScanImageRootVisitor(MarkHeapReferenceCallback* callback, void* arg,
- space::ContinuousSpace* from_space,
+ space::ContinuousSpace* from_space, space::ImageSpace* image_space,
bool* contains_reference_to_other_space)
- : callback_(callback), arg_(arg), from_space_(from_space),
+ : callback_(callback), arg_(arg), from_space_(from_space), image_space_(image_space),
contains_reference_to_other_space_(contains_reference_to_other_space) {}
void operator()(Object* root) const
EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
DCHECK(root != NULL);
- ModUnionUpdateObjectReferencesVisitor ref_visitor(callback_, arg_, from_space_,
+ ModUnionUpdateObjectReferencesVisitor ref_visitor(callback_, arg_, from_space_, image_space_,
contains_reference_to_other_space_);
root->VisitReferences<kMovingClasses>(ref_visitor, VoidFunctor());
}
@@ -124,6 +127,7 @@
void* const arg_;
// Space which we are scanning
space::ContinuousSpace* const from_space_;
+ space::ImageSpace* const image_space_;
// Set if we have any references to another space.
bool* const contains_reference_to_other_space_;
};
@@ -331,9 +335,11 @@
void ModUnionTableCardCache::UpdateAndMarkReferences(MarkHeapReferenceCallback* callback,
void* arg) {
CardTable* card_table = heap_->GetCardTable();
+ space::ImageSpace* image_space = heap_->GetImageSpace();
ContinuousSpaceBitmap* bitmap = space_->GetLiveBitmap();
bool reference_to_other_space = false;
- ModUnionScanImageRootVisitor scan_visitor(callback, arg, space_, &reference_to_other_space);
+ ModUnionScanImageRootVisitor scan_visitor(callback, arg, space_, image_space,
+ &reference_to_other_space);
for (auto it = cleared_cards_.begin(), end = cleared_cards_.end(); it != end; ) {
uintptr_t start = reinterpret_cast<uintptr_t>(card_table->AddrFromCard(*it));
DCHECK(space_->HasAddress(reinterpret_cast<Object*>(start)));
