src/hotspot/share/gc/g1/g1Allocator.cpp

rev 55208 : imported patch 8220089.webrev.0
rev 55210 : imported patch 8220089.webrev.2
rev 55211 : imported patch 8220089.webrev.3
rev 55212 : imported patch 8220089.webrev.4

*** 39,54 ****
    _survivor_is_full(false),
    _old_is_full(false),
    _mutator_alloc_region(),
    _survivor_gc_alloc_region(heap->alloc_buffer_stats(G1HeapRegionAttr::Young)),
    _old_gc_alloc_region(heap->alloc_buffer_stats(G1HeapRegionAttr::Old)),
!   _retained_old_gc_alloc_region(NULL) {
  }
  
  void G1Allocator::init_mutator_alloc_region() {
    assert(_mutator_alloc_region.get() == NULL, "pre-condition");
    _mutator_alloc_region.init();
  }
  
  void G1Allocator::release_mutator_alloc_region() {
    _mutator_alloc_region.release();
    assert(_mutator_alloc_region.get() == NULL, "post-condition");
--- 39,67 ----
    _survivor_is_full(false),
    _old_is_full(false),
    _mutator_alloc_region(),
    _survivor_gc_alloc_region(heap->alloc_buffer_stats(G1HeapRegionAttr::Young)),
    _old_gc_alloc_region(heap->alloc_buffer_stats(G1HeapRegionAttr::Old)),
!   _retained_old_gc_alloc_region(NULL),
!   _retained_survivor_gc_alloc_region(NULL) {
  }
  
  void G1Allocator::init_mutator_alloc_region() {
    assert(_mutator_alloc_region.get() == NULL, "pre-condition");
    _mutator_alloc_region.init();
+ 
+   reuse_retained_survivor_region(&_retained_survivor_gc_alloc_region);
+ }
+ 
+ void G1Allocator::reuse_retained_survivor_region(HeapRegion** retained_survivor) {
+   HeapRegion* retained_region = *retained_survivor;
+   *retained_survivor = NULL;
+ 
+   if (retained_region != NULL) {
+     mutator_alloc_region()->set(retained_region);
+     _g1h->reuse_retained_survivor_region(retained_region);
+   }
  }
  
  void G1Allocator::release_mutator_alloc_region() {
    _mutator_alloc_region.release();
    assert(_mutator_alloc_region.get() == NULL, "post-condition");
*** 105,115 ****
  }
  
  void G1Allocator::release_gc_alloc_regions(G1EvacuationInfo& evacuation_info) {
    evacuation_info.set_allocation_regions(survivor_gc_alloc_region()->count() +
                                           old_gc_alloc_region()->count());
!   survivor_gc_alloc_region()->release();
    // If we have an old GC alloc region to release, we'll save it in
    // _retained_old_gc_alloc_region. If we don't
    // _retained_old_gc_alloc_region will become NULL. This is what we
    // want either way so no reason to check explicitly for either
    // condition.
--- 118,133 ----
  }
  
  void G1Allocator::release_gc_alloc_regions(G1EvacuationInfo& evacuation_info) {
    evacuation_info.set_allocation_regions(survivor_gc_alloc_region()->count() +
                                           old_gc_alloc_region()->count());
!   HeapRegion* reuse_candidate = survivor_gc_alloc_region()->release();
!   if (reuse_candidate != NULL && SurvivorGCAllocRegion::should_retain(reuse_candidate)) {
!     _g1h->update_retained_survivor_gc_alloc_region(reuse_candidate);
!     _retained_survivor_gc_alloc_region = reuse_candidate;
!   }
! 
    // If we have an old GC alloc region to release, we'll save it in
    // _retained_old_gc_alloc_region. If we don't
    // _retained_old_gc_alloc_region will become NULL. This is what we
    // want either way so no reason to check explicitly for either
    // condition.