jdk8-mips64-public/hotspot: src/share/vm/memory/collectorPolicy.hpp@7ae4e26cb1e0 (annotated)

src/share/vm/memory/collectorPolicy.hpp@7ae4e26cb1e0 (annotated)

src/share/vm/memory/collectorPolicy.hpp

Thu, 12 Oct 2017 21:27:07 +0800

author: aoqi
date: Thu, 12 Oct 2017 21:27:07 +0800
changeset 7535: 7ae4e26cb1e0
parent 6876: 710a3c8b516e
permissions: -rw-r--r--

merge

 /*
  * Copyright (c) 2001, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #ifndef SHARE_VM_MEMORY_COLLECTORPOLICY_HPP
 #define SHARE_VM_MEMORY_COLLECTORPOLICY_HPP
 #include "memory/allocation.hpp"
 #include "memory/barrierSet.hpp"
 #include "memory/generationSpec.hpp"
 #include "memory/genRemSet.hpp"
 #include "utilities/macros.hpp"
 // This class (or more correctly, subtypes of this class)
 // are used to define global garbage collector attributes.
 // This includes initialization of generations and any other
 // shared resources they may need.
 //
 // In general, all flag adjustment and validation should be
 // done in initialize_flags(), which is called prior to
 // initialize_size_info().
 //
 // This class is not fully developed yet. As more collector(s)
 // are added, it is expected that we will come across further
 // behavior that requires global attention. The correct place
 // to deal with those issues is this class.
 // Forward declarations.
 class GenCollectorPolicy;
 class TwoGenerationCollectorPolicy;
 class AdaptiveSizePolicy;
 #if INCLUDE_ALL_GCS
 class ConcurrentMarkSweepPolicy;
 class G1CollectorPolicy;
 #endif // INCLUDE_ALL_GCS
 class GCPolicyCounters;
 class MarkSweepPolicy;
 class CollectorPolicy : public CHeapObj<mtGC> {
  protected:
   GCPolicyCounters* _gc_policy_counters;
   virtual void initialize_alignments() = 0;
   virtual void initialize_flags();
   virtual void initialize_size_info();
   DEBUG_ONLY(virtual void assert_flags();)
   DEBUG_ONLY(virtual void assert_size_info();)
   size_t _initial_heap_byte_size;
   size_t _max_heap_byte_size;
   size_t _min_heap_byte_size;
   size_t _space_alignment;
   size_t _heap_alignment;
   // Needed to keep information if MaxHeapSize was set on the command line
   // when the flag value is aligned etc by ergonomics
   bool _max_heap_size_cmdline;
   // The sizing of the heap are controlled by a sizing policy.
   AdaptiveSizePolicy* _size_policy;
   // Set to true when policy wants soft refs cleared.
   // Reset to false by gc after it clears all soft refs.
   bool _should_clear_all_soft_refs;
   // Set to true by the GC if the just-completed gc cleared all
   // softrefs.  This is set to true whenever a gc clears all softrefs, and
   // set to false each time gc returns to the mutator.  For example, in the
   // ParallelScavengeHeap case the latter would be done toward the end of
   // mem_allocate() where it returns op.result()
   bool _all_soft_refs_clear;
   CollectorPolicy();
  public:
   virtual void initialize_all() {
     initialize_alignments();
     initialize_flags();
     initialize_size_info();
   }
   // Return maximum heap alignment that may be imposed by the policy
   static size_t compute_heap_alignment();
   size_t space_alignment()        { return _space_alignment; }
   size_t heap_alignment()         { return _heap_alignment; }
   size_t initial_heap_byte_size() { return _initial_heap_byte_size; }
   size_t max_heap_byte_size()     { return _max_heap_byte_size; }
   size_t min_heap_byte_size()     { return _min_heap_byte_size; }
   enum Name {
     CollectorPolicyKind,
     TwoGenerationCollectorPolicyKind,
     ConcurrentMarkSweepPolicyKind,
     ASConcurrentMarkSweepPolicyKind,
     G1CollectorPolicyKind
   };
   AdaptiveSizePolicy* size_policy() { return _size_policy; }
   bool should_clear_all_soft_refs() { return _should_clear_all_soft_refs; }
   void set_should_clear_all_soft_refs(bool v) { _should_clear_all_soft_refs = v; }
   // Returns the current value of _should_clear_all_soft_refs.
   // _should_clear_all_soft_refs is set to false as a side effect.
   bool use_should_clear_all_soft_refs(bool v);
   bool all_soft_refs_clear() { return _all_soft_refs_clear; }
   void set_all_soft_refs_clear(bool v) { _all_soft_refs_clear = v; }
   // Called by the GC after Soft Refs have been cleared to indicate
   // that the request in _should_clear_all_soft_refs has been fulfilled.
   void cleared_all_soft_refs();
   // Identification methods.
   virtual GenCollectorPolicy*           as_generation_policy()            { return NULL; }
   virtual TwoGenerationCollectorPolicy* as_two_generation_policy()        { return NULL; }
   virtual MarkSweepPolicy*              as_mark_sweep_policy()            { return NULL; }
 #if INCLUDE_ALL_GCS
   virtual ConcurrentMarkSweepPolicy*    as_concurrent_mark_sweep_policy() { return NULL; }
   virtual G1CollectorPolicy*            as_g1_policy()                    { return NULL; }
 #endif // INCLUDE_ALL_GCS
   // Note that these are not virtual.
   bool is_generation_policy()            { return as_generation_policy() != NULL; }
   bool is_two_generation_policy()        { return as_two_generation_policy() != NULL; }
   bool is_mark_sweep_policy()            { return as_mark_sweep_policy() != NULL; }
 #if INCLUDE_ALL_GCS
   bool is_concurrent_mark_sweep_policy() { return as_concurrent_mark_sweep_policy() != NULL; }
   bool is_g1_policy()                    { return as_g1_policy() != NULL; }
 #else  // INCLUDE_ALL_GCS
   bool is_concurrent_mark_sweep_policy() { return false; }
   bool is_g1_policy()                    { return false; }
 #endif // INCLUDE_ALL_GCS
   virtual BarrierSet::Name barrier_set_name() = 0;
   // Create the remembered set (to cover the given reserved region,
   // allowing breaking up into at most "max_covered_regions").
   virtual GenRemSet* create_rem_set(MemRegion reserved,
                                     int max_covered_regions);
   // This method controls how a collector satisfies a request
   // for a block of memory.  "gc_time_limit_was_exceeded" will
   // be set to true if the adaptive size policy determine that
   // an excessive amount of time is being spent doing collections
   // and caused a NULL to be returned.  If a NULL is not returned,
   // "gc_time_limit_was_exceeded" has an undefined meaning.
   virtual HeapWord* mem_allocate_work(size_t size,
                                       bool is_tlab,
                                       bool* gc_overhead_limit_was_exceeded) = 0;
   // This method controls how a collector handles one or more
   // of its generations being fully allocated.
   virtual HeapWord *satisfy_failed_allocation(size_t size, bool is_tlab) = 0;
   // This method controls how a collector handles a metadata allocation
   // failure.
   virtual MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
                                                        size_t size,
                                                        Metaspace::MetadataType mdtype);
   // Performace Counter support
   GCPolicyCounters* counters()     { return _gc_policy_counters; }
   // Create the jstat counters for the GC policy.  By default, policy's
   // don't have associated counters, and we complain if this is invoked.
   virtual void initialize_gc_policy_counters() {
     ShouldNotReachHere();
   }
   virtual CollectorPolicy::Name kind() {
     return CollectorPolicy::CollectorPolicyKind;
   }
   // Returns true if a collector has eden space with soft end.
   virtual bool has_soft_ended_eden() {
     return false;
   }
   // Do any updates required to global flags that are due to heap initialization
   // changes
   virtual void post_heap_initialize() = 0;
 };
 class ClearedAllSoftRefs : public StackObj {
   bool _clear_all_soft_refs;
   CollectorPolicy* _collector_policy;
  public:
   ClearedAllSoftRefs(bool clear_all_soft_refs,
                      CollectorPolicy* collector_policy) :
     _clear_all_soft_refs(clear_all_soft_refs),
     _collector_policy(collector_policy) {}
   ~ClearedAllSoftRefs() {
     if (_clear_all_soft_refs) {
       _collector_policy->cleared_all_soft_refs();
     }
   }
 };
 class GenCollectorPolicy : public CollectorPolicy {
 friend class TestGenCollectorPolicy;
  protected:
   size_t _min_gen0_size;
   size_t _initial_gen0_size;
   size_t _max_gen0_size;
   // _gen_alignment and _space_alignment will have the same value most of the
   // time. When using large pages they can differ.
   size_t _gen_alignment;
   GenerationSpec **_generations;
   // Return true if an allocation should be attempted in the older
   // generation if it fails in the younger generation.  Return
   // false, otherwise.
   virtual bool should_try_older_generation_allocation(size_t word_size) const;
   void initialize_flags();
   void initialize_size_info();
   DEBUG_ONLY(void assert_flags();)
   DEBUG_ONLY(void assert_size_info();)
   // Try to allocate space by expanding the heap.
   virtual HeapWord* expand_heap_and_allocate(size_t size, bool is_tlab);
   // Compute max heap alignment
   size_t compute_max_alignment();
  // Scale the base_size by NewRatio according to
  //     result = base_size / (NewRatio + 1)
  // and align by min_alignment()
  size_t scale_by_NewRatio_aligned(size_t base_size);
  // Bound the value by the given maximum minus the min_alignment
  size_t bound_minus_alignment(size_t desired_size, size_t maximum_size);
  public:
   GenCollectorPolicy();
   // Accessors
   size_t min_gen0_size()     { return _min_gen0_size; }
   size_t initial_gen0_size() { return _initial_gen0_size; }
   size_t max_gen0_size()     { return _max_gen0_size; }
   size_t gen_alignment()     { return _gen_alignment; }
   virtual int number_of_generations() = 0;
   virtual GenerationSpec **generations() {
     assert(_generations != NULL, "Sanity check");
     return _generations;
   }
   virtual GenCollectorPolicy* as_generation_policy() { return this; }
   virtual void initialize_generations() { };
   virtual void initialize_all() {
     CollectorPolicy::initialize_all();
     initialize_generations();
   }
   size_t young_gen_size_lower_bound();
   HeapWord* mem_allocate_work(size_t size,
                               bool is_tlab,
                               bool* gc_overhead_limit_was_exceeded);
   HeapWord *satisfy_failed_allocation(size_t size, bool is_tlab);
   // Adaptive size policy
   virtual void initialize_size_policy(size_t init_eden_size,
                                       size_t init_promo_size,
                                       size_t init_survivor_size);
   virtual void post_heap_initialize() {
     assert(_max_gen0_size == MaxNewSize, "Should be taken care of by initialize_size_info");
   }
 };
 // All of hotspot's current collectors are subtypes of this
 // class. Currently, these collectors all use the same gen[0],
 // but have different gen[1] types. If we add another subtype
 // of CollectorPolicy, this class should be broken out into
 // its own file.
 class TwoGenerationCollectorPolicy : public GenCollectorPolicy {
  protected:
   size_t _min_gen1_size;
   size_t _initial_gen1_size;
   size_t _max_gen1_size;
   void initialize_flags();
   void initialize_size_info();
   DEBUG_ONLY(void assert_flags();)
   DEBUG_ONLY(void assert_size_info();)
  public:
   TwoGenerationCollectorPolicy() : GenCollectorPolicy(), _min_gen1_size(0),
     _initial_gen1_size(0), _max_gen1_size(0) {}
   // Accessors
   size_t min_gen1_size()     { return _min_gen1_size; }
   size_t initial_gen1_size() { return _initial_gen1_size; }
   size_t max_gen1_size()     { return _max_gen1_size; }
   // Inherited methods
   TwoGenerationCollectorPolicy* as_two_generation_policy() { return this; }
   int number_of_generations()          { return 2; }
   BarrierSet::Name barrier_set_name()  { return BarrierSet::CardTableModRef; }
   virtual CollectorPolicy::Name kind() {
     return CollectorPolicy::TwoGenerationCollectorPolicyKind;
   }
   // Returns true if gen0 sizes were adjusted
   bool adjust_gen0_sizes(size_t* gen0_size_ptr, size_t* gen1_size_ptr,
                          const size_t heap_size);
 };
 class MarkSweepPolicy : public TwoGenerationCollectorPolicy {
  protected:
   void initialize_alignments();
   void initialize_generations();
  public:
   MarkSweepPolicy() {}
   MarkSweepPolicy* as_mark_sweep_policy() { return this; }
   void initialize_gc_policy_counters();
 };
 #endif // SHARE_VM_MEMORY_COLLECTORPOLICY_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/memory/collectorPolicy.hpp@7ae4e26cb1e0 (annotated)

src/share/vm/memory/collectorPolicy.hpp