# HG changeset patch
# User rkennke
# Date 1490902927 -7200
#      Thu Mar 30 21:42:07 2017 +0200
# Node ID 85ad2bfde517205f6e8f7da4e0b23faccee95665
# Parent  eb6ebd9816cf2a1849864bcbf41abc65eb8a4e45
Interleave partial GCs with concurrent GCs.

diff --git a/src/share/vm/gc/shenandoah/shenandoahCollectorPolicy.cpp b/src/share/vm/gc/shenandoah/shenandoahCollectorPolicy.cpp
--- a/src/share/vm/gc/shenandoah/shenandoahCollectorPolicy.cpp
+++ b/src/share/vm/gc/shenandoah/shenandoahCollectorPolicy.cpp
@@ -684,9 +684,8 @@
 
   virtual ~PartialHeuristics() {}
 
-  bool should_start_concurrent_mark(size_t used, size_t capacity) const {
-    // Never do concurrent GCs.
-    return false;
+  bool update_refs_early() {
+    return true;
   }
 
   bool should_start_partial_gc() {
diff --git a/src/share/vm/gc/shenandoah/shenandoahHeap.cpp b/src/share/vm/gc/shenandoah/shenandoahHeap.cpp
--- a/src/share/vm/gc/shenandoah/shenandoahHeap.cpp
+++ b/src/share/vm/gc/shenandoah/shenandoahHeap.cpp
@@ -2637,6 +2637,7 @@
   set_evacuation_in_progress_at_safepoint(false);
   set_update_refs_in_progress(true);
   ensure_parsability(true);
+  connection_matrix()->clear_all();
   for (uint i = 0; i < _num_regions; i++) {
     ShenandoahHeapRegion* r = _ordered_regions->get(i);
     r->set_concurrent_iteration_safe_limit(r->top());
diff --git a/src/share/vm/gc/shenandoah/shenandoahHeap.inline.hpp b/src/share/vm/gc/shenandoah/shenandoahHeap.inline.hpp
--- a/src/share/vm/gc/shenandoah/shenandoahHeap.inline.hpp
+++ b/src/share/vm/gc/shenandoah/shenandoahHeap.inline.hpp
@@ -430,6 +430,8 @@
 inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit) {
   assert(BrooksPointer::word_offset() < 0, "skip_delta calculation below assumes the forwarding ptr is before obj");
 
+  assert(! region->is_humongous_continuation(), "no humongous continuation regions here");
+
   CMBitMap* mark_bit_map = _complete_mark_bit_map;
   HeapWord* top_at_mark_start = complete_top_at_mark_start(region->bottom());
 
diff --git a/src/share/vm/gc/shenandoah/shenandoahOopClosures.inline.hpp b/src/share/vm/gc/shenandoah/shenandoahOopClosures.inline.hpp
--- a/src/share/vm/gc/shenandoah/shenandoahOopClosures.inline.hpp
+++ b/src/share/vm/gc/shenandoah/shenandoahOopClosures.inline.hpp
@@ -34,7 +34,10 @@
 
 template <class T>
 inline void ShenandoahUpdateHeapRefsClosure::do_oop_nv(T* p) {
-  _heap->maybe_update_oop_ref(p);
+  oop obj = _heap->maybe_update_oop_ref(p);
+  if (! oopDesc::is_null(obj)) {
+    _heap->connection_matrix()->set_connected(p, obj);
+  }
 }
 
 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHOOPCLOSURES_INLINE_HPP
diff --git a/src/share/vm/gc/shenandoah/shenandoahPartialGC.cpp b/src/share/vm/gc/shenandoah/shenandoahPartialGC.cpp
--- a/src/share/vm/gc/shenandoah/shenandoahPartialGC.cpp
+++ b/src/share/vm/gc/shenandoah/shenandoahPartialGC.cpp
@@ -106,7 +106,9 @@
       ShenandoahHeapRegion* r = _root_regions->claim_next();
       while (r != NULL) {
         assert(r->is_root(), "must be root region");
-        r->oop_iterate(&cl);
+        if (! r->is_humongous_continuation()) {
+          _heap->marked_object_oop_iterate(r, &cl);
+        }
         r->set_root(false);
         if (check_and_handle_cancelled_gc()) return;
         r = _root_regions->claim_next();
@@ -299,6 +301,11 @@
       for (size_t i = 0; i < num_cset; i++) {
         ShenandoahHeapRegion* r = _heap->collection_set()->get(i);
         _heap->decrease_used(r->used());
+        HeapWord* bottom = r->bottom();
+        HeapWord* top = _heap->complete_top_at_mark_start(r->bottom());
+        if (top > bottom) {
+          _heap->complete_mark_bit_map()->clear_range_large(MemRegion(bottom, top));
+        }
         r->recycle();
         _heap->free_regions()->add_region(r);
       }
@@ -343,7 +350,7 @@
     if (UPDATE_MATRIX) {
 #ifdef ASSERT
       oop forw = ShenandoahBarrierSet::resolve_oop_static_not_null(obj);
-      assert(oopDesc::unsafe_equals(obj, forw) || _heap->cancelled_concgc(), "must not be evacuated");
+      assert(oopDesc::unsafe_equals(obj, forw) || _heap->cancelled_concgc(), "must not be evacuated: "PTR_FORMAT" -> "PTR_FORMAT, p2i(obj), p2i(forw));
 #endif
       _matrix->set_connected(p, obj);
     }