hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.hpp
changeset 1 489c9b5090e2
child 360 21d113ecbf6a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,277 @@
+/*
+ * Copyright 2002-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+//
+// psPromotionManager is used by a single thread to manage object survival
+// during a scavenge. The promotion manager contains thread local data only.
+//
+// NOTE! Be carefull when allocating the stacks on cheap. If you are going
+// to use a promotion manager in more than one thread, the stacks MUST be
+// on cheap. This can lead to memory leaks, though, as they are not auto
+// deallocated.
+//
+// FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate!
+//
+
+// Move to some global location
+#define HAS_BEEN_MOVED 0x1501d01d
+// End move to some global location
+
+class MutableSpace;
+class PSOldGen;
+class ParCompactionManager;
+
+#define PS_CHUNKED_ARRAY_OOP_MASK  1
+
+#define PS_PM_STATS         0
+
+class PSPromotionManager : public CHeapObj {
+  friend class PSScavenge;
+  friend class PSRefProcTaskExecutor;
+ private:
+  static PSPromotionManager**         _manager_array;
+  static OopStarTaskQueueSet*         _stack_array_depth;
+  static OopTaskQueueSet*             _stack_array_breadth;
+  static PSOldGen*                    _old_gen;
+  static MutableSpace*                _young_space;
+
+#if PS_PM_STATS
+  uint                                _total_pushes;
+  uint                                _masked_pushes;
+
+  uint                                _overflow_pushes;
+  uint                                _max_overflow_length;
+
+  uint                                _arrays_chunked;
+  uint                                _array_chunks_processed;
+
+  uint                                _total_steals;
+  uint                                _masked_steals;
+
+  void print_stats(uint i);
+  static void print_stats();
+#endif // PS_PM_STATS
+
+  PSYoungPromotionLAB                 _young_lab;
+  PSOldPromotionLAB                   _old_lab;
+  bool                                _young_gen_is_full;
+  bool                                _old_gen_is_full;
+  PrefetchQueue                       _prefetch_queue;
+
+  OopStarTaskQueue                    _claimed_stack_depth;
+  GrowableArray<oop*>*                _overflow_stack_depth;
+  OopTaskQueue                        _claimed_stack_breadth;
+  GrowableArray<oop>*                 _overflow_stack_breadth;
+
+  bool                                _depth_first;
+  bool                                _totally_drain;
+  uint                                _target_stack_size;
+
+  uint                                _array_chunk_size;
+  uint                                _min_array_size_for_chunking;
+
+  // Accessors
+  static PSOldGen* old_gen()              { return _old_gen; }
+  static MutableSpace* young_space()      { return _young_space; }
+
+  inline static PSPromotionManager* manager_array(int index);
+
+  GrowableArray<oop*>* overflow_stack_depth()  { return _overflow_stack_depth; }
+  GrowableArray<oop>* overflow_stack_breadth()   { return _overflow_stack_breadth; }
+
+  // On the task queues we push reference locations as well as
+  // partially-scanned arrays (in the latter case, we push an oop to
+  // the from-space image of the array and the length on the
+  // from-space image indicates how many entries on the array we still
+  // need to scan; this is basically how ParNew does partial array
+  // scanning too). To be able to distinguish between reference
+  // locations and partially-scanned array oops we simply mask the
+  // latter oops with 0x01. The next three methods do the masking,
+  // unmasking, and checking whether the oop is masked or not. Notice
+  // that the signature of the mask and unmask methods looks a bit
+  // strange, as they accept and return different types (oop and
+  // oop*). This is because of the difference in types between what
+  // the task queue holds (oop*) and oops to partially-scanned arrays
+  // (oop). We do all the necessary casting in the mask / unmask
+  // methods to avoid sprinkling the rest of the code with more casts.
+
+  bool is_oop_masked(oop* p) {
+    return ((intptr_t) p & PS_CHUNKED_ARRAY_OOP_MASK) == PS_CHUNKED_ARRAY_OOP_MASK;
+  }
+
+  oop* mask_chunked_array_oop(oop obj) {
+    assert(!is_oop_masked((oop*) obj), "invariant");
+    oop* ret = (oop*) ((intptr_t) obj  | PS_CHUNKED_ARRAY_OOP_MASK);
+    assert(is_oop_masked(ret), "invariant");
+    return ret;
+  }
+
+  oop unmask_chunked_array_oop(oop* p) {
+    assert(is_oop_masked(p), "invariant");
+    oop ret = oop((intptr_t) p & ~PS_CHUNKED_ARRAY_OOP_MASK);
+    assert(!is_oop_masked((oop*) ret), "invariant");
+    return ret;
+  }
+
+  void process_array_chunk(oop old);
+
+  void push_depth(oop* p) {
+    assert(depth_first(), "pre-condition");
+
+#if PS_PM_STATS
+    ++_total_pushes;
+#endif // PS_PM_STATS
+
+    if (!claimed_stack_depth()->push(p)) {
+      overflow_stack_depth()->push(p);
+#if PS_PM_STATS
+      ++_overflow_pushes;
+      uint stack_length = (uint) overflow_stack_depth()->length();
+      if (stack_length > _max_overflow_length) {
+        _max_overflow_length = stack_length;
+      }
+#endif // PS_PM_STATS
+    }
+  }
+
+  void push_breadth(oop o) {
+    assert(!depth_first(), "pre-condition");
+
+#if PS_PM_STATS
+    ++_total_pushes;
+#endif // PS_PM_STATS
+
+    if(!claimed_stack_breadth()->push(o)) {
+      overflow_stack_breadth()->push(o);
+#if PS_PM_STATS
+      ++_overflow_pushes;
+      uint stack_length = (uint) overflow_stack_breadth()->length();
+      if (stack_length > _max_overflow_length) {
+        _max_overflow_length = stack_length;
+      }
+#endif // PS_PM_STATS
+    }
+  }
+
+ protected:
+  static OopStarTaskQueueSet* stack_array_depth() { return _stack_array_depth; }
+  static OopTaskQueueSet*     stack_array_breadth() { return _stack_array_breadth; }
+
+ public:
+  // Static
+  static void initialize();
+
+  static void pre_scavenge();
+  static void post_scavenge();
+
+  static PSPromotionManager* gc_thread_promotion_manager(int index);
+  static PSPromotionManager* vm_thread_promotion_manager();
+
+  static bool steal_depth(int queue_num, int* seed, StarTask& t) {
+    assert(stack_array_depth() != NULL, "invariant");
+    return stack_array_depth()->steal(queue_num, seed, t);
+  }
+
+  static bool steal_breadth(int queue_num, int* seed, Task& t) {
+    assert(stack_array_breadth() != NULL, "invariant");
+    return stack_array_breadth()->steal(queue_num, seed, t);
+  }
+
+  PSPromotionManager();
+
+  // Accessors
+  OopStarTaskQueue* claimed_stack_depth() {
+    return &_claimed_stack_depth;
+  }
+  OopTaskQueue* claimed_stack_breadth() {
+    return &_claimed_stack_breadth;
+  }
+
+  bool young_gen_is_full()             { return _young_gen_is_full; }
+
+  bool old_gen_is_full()               { return _old_gen_is_full; }
+  void set_old_gen_is_full(bool state) { _old_gen_is_full = state; }
+
+  // Promotion methods
+  oop copy_to_survivor_space(oop o, bool depth_first);
+  oop oop_promotion_failed(oop obj, markOop obj_mark);
+
+  void reset();
+
+  void flush_labs();
+  void drain_stacks(bool totally_drain) {
+    if (depth_first()) {
+      drain_stacks_depth(totally_drain);
+    } else {
+      drain_stacks_breadth(totally_drain);
+    }
+  }
+  void drain_stacks_cond_depth() {
+    if (claimed_stack_depth()->size() > _target_stack_size) {
+      drain_stacks_depth(false);
+    }
+  }
+  void drain_stacks_depth(bool totally_drain);
+  void drain_stacks_breadth(bool totally_drain);
+
+  bool claimed_stack_empty() {
+    if (depth_first()) {
+      return claimed_stack_depth()->size() <= 0;
+    } else {
+      return claimed_stack_breadth()->size() <= 0;
+    }
+  }
+  bool overflow_stack_empty() {
+    if (depth_first()) {
+      return overflow_stack_depth()->length() <= 0;
+    } else {
+      return overflow_stack_breadth()->length() <= 0;
+    }
+  }
+  bool stacks_empty() {
+    return claimed_stack_empty() && overflow_stack_empty();
+  }
+  bool depth_first() {
+    return _depth_first;
+  }
+
+  inline void process_popped_location_depth(oop* p);
+
+  inline void flush_prefetch_queue();
+
+  inline void claim_or_forward_depth(oop* p);
+  inline void claim_or_forward_internal_depth(oop* p);
+
+  inline void claim_or_forward_breadth(oop* p);
+  inline void claim_or_forward_internal_breadth(oop* p);
+
+#if PS_PM_STATS
+  void increment_steals(oop* p = NULL) {
+    _total_steals += 1;
+    if (p != NULL && is_oop_masked(p)) {
+      _masked_steals += 1;
+    }
+  }
+#endif // PS_PM_STATS
+};