# HG changeset patch
# Parent  a22af2c3d969665c49fd813e32ff3c2bada41631

diff -r a22af2c3d969 src/hotspot/share/gc/shenandoah/shenandoahAllocRequest.hpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahAllocRequest.hpp	Mon Jun 15 12:28:27 2020 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahAllocRequest.hpp	Mon Jun 15 21:58:44 2020 +0200
@@ -27,6 +27,12 @@
 
 #include "memory/allocation.hpp"
 
+enum ShenandoahGeneration {
+  YOUNG_GEN,
+  OLD_GEN,
+  NO_GEN
+};
+
 class ShenandoahAllocRequest : StackObj {
 public:
   enum Type {
@@ -58,13 +64,14 @@
   size_t _requested_size;
   size_t _actual_size;
   Type _alloc_type;
+  ShenandoahGeneration const _generation;
 #ifdef ASSERT
   bool _actual_size_set;
 #endif
 
-  ShenandoahAllocRequest(size_t _min_size, size_t _requested_size, Type _alloc_type) :
+  ShenandoahAllocRequest(size_t _min_size, size_t _requested_size, Type _alloc_type, ShenandoahGeneration generation) :
           _min_size(_min_size), _requested_size(_requested_size),
-          _actual_size(0), _alloc_type(_alloc_type)
+          _actual_size(0), _alloc_type(_alloc_type), _generation(generation)
 #ifdef ASSERT
           , _actual_size_set(false)
 #endif
@@ -72,19 +79,19 @@
 
 public:
   static inline ShenandoahAllocRequest for_tlab(size_t min_size, size_t requested_size) {
-    return ShenandoahAllocRequest(min_size, requested_size, _alloc_tlab);
+    return ShenandoahAllocRequest(min_size, requested_size, _alloc_tlab, YOUNG_GEN);
   }
 
   static inline ShenandoahAllocRequest for_gclab(size_t min_size, size_t requested_size) {
-    return ShenandoahAllocRequest(min_size, requested_size, _alloc_gclab);
+    return ShenandoahAllocRequest(min_size, requested_size, _alloc_gclab, YOUNG_GEN);
   }
 
-  static inline ShenandoahAllocRequest for_shared_gc(size_t requested_size) {
-    return ShenandoahAllocRequest(0, requested_size, _alloc_shared_gc);
+  static inline ShenandoahAllocRequest for_shared_gc(size_t requested_size, ShenandoahGeneration generation) {
+    return ShenandoahAllocRequest(0, requested_size, _alloc_shared_gc, generation);
   }
 
   static inline ShenandoahAllocRequest for_shared(size_t requested_size) {
-    return ShenandoahAllocRequest(0, requested_size, _alloc_shared);
+    return ShenandoahAllocRequest(0, requested_size, _alloc_shared, YOUNG_GEN);
   }
 
   inline size_t size() {
@@ -158,6 +165,10 @@
         return false;
     }
   }
+
+  ShenandoahGeneration generation() const {
+    return _generation;
+  }
 };
 
 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHALLOCREQUEST_HPP
diff -r a22af2c3d969 src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp	Mon Jun 15 12:28:27 2020 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp	Mon Jun 15 21:58:44 2020 +0200
@@ -146,6 +146,12 @@
     return NULL;
   }
 
+  if (r->generation() == NO_GEN) {
+    r->set_generation(req.generation());
+  } else if (r->generation() != req.generation()) {
+    return NULL;
+  }
+
   try_recycle_trashed(r);
 
   in_new_region = r->is_empty();
diff -r a22af2c3d969 src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp	Mon Jun 15 12:28:27 2020 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp	Mon Jun 15 21:58:44 2020 +0200
@@ -262,6 +262,19 @@
   assert(ShenandoahThreadLocalData::is_evac_allowed(thread), "must be enclosed in oom-evac scope");
 
   size_t size = p->size();
+  ShenandoahGeneration target_gen = heap_region_containing(p)->generation();
+  if (target_gen == YOUNG_GEN) {
+    markWord mark = p->mark();
+    if (mark.is_marked()) {
+      // Already forwarded.
+      return ShenandoahBarrierSet::resolve_forwarded(p);
+    } else {
+      if (mark.age() > InitialTenuringThreshold) {
+        //tty->print_cr("promoting object: " PTR_FORMAT, p2i(p));
+        target_gen = OLD_GEN;
+      }
+    }
+  }
 
   assert(!heap_region_containing(p)->is_humongous(), "never evacuate humongous objects");
 
@@ -274,11 +287,11 @@
         copy = NULL;
   } else {
 #endif
-    if (UseTLAB) {
+    if (UseTLAB && target_gen == YOUNG_GEN) {
       copy = allocate_from_gclab(thread, size);
     }
     if (copy == NULL) {
-      ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared_gc(size);
+      ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared_gc(size, target_gen);
       copy = allocate_memory(req);
       alloc_from_gclab = false;
     }
@@ -303,6 +316,12 @@
   if (result == copy_val) {
     // Successfully evacuated. Our copy is now the public one!
     shenandoah_assert_correct(NULL, copy_val);
+
+    // Increment age in young copies
+    if (target_gen == YOUNG_GEN) {
+      copy_val->incr_age();
+    }
+
     return copy_val;
   }  else {
     // Failed to evacuate. We need to deal with the object that is left behind. Since this
diff -r a22af2c3d969 src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp	Mon Jun 15 12:28:27 2020 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp	Mon Jun 15 21:58:44 2020 +0200
@@ -64,7 +64,8 @@
   _gclab_allocs(0),
   _live_data(0),
   _critical_pins(0),
-  _update_watermark(start) {
+  _update_watermark(start),
+  _generation(NO_GEN) {
 
   assert(Universe::on_page_boundary(_bottom) && Universe::on_page_boundary(_end),
          "invalid space boundaries");
@@ -359,6 +360,19 @@
     default:
       ShouldNotReachHere();
   }
+  switch (_generation) {
+    case YOUNG_GEN:
+      st->print("|Y");
+      break;
+    case OLD_GEN:
+      st->print("|O");
+      break;
+    case NO_GEN:
+      st->print("| ");
+      break;
+    default:
+      ShouldNotReachHere();
+  }
   st->print("|BTE " INTPTR_FORMAT_W(12) ", " INTPTR_FORMAT_W(12) ", " INTPTR_FORMAT_W(12),
             p2i(bottom()), p2i(top()), p2i(end()));
   st->print("|TAMS " INTPTR_FORMAT_W(12),
@@ -428,6 +442,7 @@
   set_update_watermark(bottom());
 
   make_empty();
+  _generation = NO_GEN;
 
   if (ZapUnusedHeapArea) {
     SpaceMangler::mangle_region(MemRegion(bottom(), end()));
diff -r a22af2c3d969 src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.hpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.hpp	Mon Jun 15 12:28:27 2020 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.hpp	Mon Jun 15 21:58:44 2020 +0200
@@ -245,6 +245,8 @@
 
   HeapWord* volatile _update_watermark;
 
+  ShenandoahGeneration _generation;
+
 public:
   ShenandoahHeapRegion(HeapWord* start, size_t index, bool committed);
 
@@ -386,6 +388,14 @@
   inline void set_update_watermark(HeapWord* w);
   inline void set_update_watermark_at_safepoint(HeapWord* w);
 
+  ShenandoahGeneration generation() const {
+    return _generation;
+  }
+
+  void set_generation(ShenandoahGeneration generation) {
+    _generation = generation;
+  }
+
 private:
   void do_commit();
   void do_uncommit();