aoqi@0: /*
aoqi@0:  * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_MEMORY_COLLECTORPOLICY_HPP
aoqi@0: #define SHARE_VM_MEMORY_COLLECTORPOLICY_HPP
aoqi@0: 
aoqi@0: #include "memory/allocation.hpp"
aoqi@0: #include "memory/barrierSet.hpp"
aoqi@0: #include "memory/generationSpec.hpp"
aoqi@0: #include "memory/genRemSet.hpp"
aoqi@0: #include "utilities/macros.hpp"
aoqi@0: 
aoqi@0: // This class (or more correctly, subtypes of this class)
aoqi@0: // are used to define global garbage collector attributes.
aoqi@0: // This includes initialization of generations and any other
aoqi@0: // shared resources they may need.
aoqi@0: //
aoqi@0: // In general, all flag adjustment and validation should be
aoqi@0: // done in initialize_flags(), which is called prior to
aoqi@0: // initialize_size_info().
aoqi@0: //
aoqi@0: // This class is not fully developed yet. As more collector(s)
aoqi@0: // are added, it is expected that we will come across further
aoqi@0: // behavior that requires global attention. The correct place
aoqi@0: // to deal with those issues is this class.
aoqi@0: 
aoqi@0: // Forward declarations.
aoqi@0: class GenCollectorPolicy;
aoqi@0: class TwoGenerationCollectorPolicy;
aoqi@0: class AdaptiveSizePolicy;
aoqi@0: #if INCLUDE_ALL_GCS
aoqi@0: class ConcurrentMarkSweepPolicy;
aoqi@0: class G1CollectorPolicy;
aoqi@0: #endif // INCLUDE_ALL_GCS
aoqi@0: 
aoqi@0: class GCPolicyCounters;
aoqi@0: class MarkSweepPolicy;
aoqi@0: 
aoqi@0: class CollectorPolicy : public CHeapObj<mtGC> {
aoqi@0:  protected:
aoqi@0:   GCPolicyCounters* _gc_policy_counters;
aoqi@0: 
aoqi@0:   virtual void initialize_alignments() = 0;
aoqi@0:   virtual void initialize_flags();
aoqi@0:   virtual void initialize_size_info();
aoqi@0: 
aoqi@0:   DEBUG_ONLY(virtual void assert_flags();)
aoqi@0:   DEBUG_ONLY(virtual void assert_size_info();)
aoqi@0: 
aoqi@0:   size_t _initial_heap_byte_size;
aoqi@0:   size_t _max_heap_byte_size;
aoqi@0:   size_t _min_heap_byte_size;
aoqi@0: 
aoqi@0:   size_t _space_alignment;
aoqi@0:   size_t _heap_alignment;
aoqi@0: 
aoqi@0:   // Needed to keep information if MaxHeapSize was set on the command line
aoqi@0:   // when the flag value is aligned etc by ergonomics
aoqi@0:   bool _max_heap_size_cmdline;
aoqi@0: 
aoqi@0:   // The sizing of the heap are controlled by a sizing policy.
aoqi@0:   AdaptiveSizePolicy* _size_policy;
aoqi@0: 
aoqi@0:   // Set to true when policy wants soft refs cleared.
aoqi@0:   // Reset to false by gc after it clears all soft refs.
aoqi@0:   bool _should_clear_all_soft_refs;
aoqi@0: 
aoqi@0:   // Set to true by the GC if the just-completed gc cleared all
aoqi@0:   // softrefs.  This is set to true whenever a gc clears all softrefs, and
aoqi@0:   // set to false each time gc returns to the mutator.  For example, in the
aoqi@0:   // ParallelScavengeHeap case the latter would be done toward the end of
aoqi@0:   // mem_allocate() where it returns op.result()
aoqi@0:   bool _all_soft_refs_clear;
aoqi@0: 
aoqi@0:   CollectorPolicy();
aoqi@0: 
aoqi@0:  public:
aoqi@0:   virtual void initialize_all() {
aoqi@0:     initialize_alignments();
aoqi@0:     initialize_flags();
aoqi@0:     initialize_size_info();
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Return maximum heap alignment that may be imposed by the policy
aoqi@0:   static size_t compute_heap_alignment();
aoqi@0: 
aoqi@0:   size_t space_alignment()        { return _space_alignment; }
aoqi@0:   size_t heap_alignment()         { return _heap_alignment; }
aoqi@0: 
aoqi@0:   size_t initial_heap_byte_size() { return _initial_heap_byte_size; }
aoqi@0:   size_t max_heap_byte_size()     { return _max_heap_byte_size; }
aoqi@0:   size_t min_heap_byte_size()     { return _min_heap_byte_size; }
aoqi@0: 
aoqi@0:   enum Name {
aoqi@0:     CollectorPolicyKind,
aoqi@0:     TwoGenerationCollectorPolicyKind,
aoqi@0:     ConcurrentMarkSweepPolicyKind,
aoqi@0:     ASConcurrentMarkSweepPolicyKind,
aoqi@0:     G1CollectorPolicyKind
aoqi@0:   };
aoqi@0: 
aoqi@0:   AdaptiveSizePolicy* size_policy() { return _size_policy; }
aoqi@0:   bool should_clear_all_soft_refs() { return _should_clear_all_soft_refs; }
aoqi@0:   void set_should_clear_all_soft_refs(bool v) { _should_clear_all_soft_refs = v; }
aoqi@0:   // Returns the current value of _should_clear_all_soft_refs.
aoqi@0:   // _should_clear_all_soft_refs is set to false as a side effect.
aoqi@0:   bool use_should_clear_all_soft_refs(bool v);
aoqi@0:   bool all_soft_refs_clear() { return _all_soft_refs_clear; }
aoqi@0:   void set_all_soft_refs_clear(bool v) { _all_soft_refs_clear = v; }
aoqi@0: 
aoqi@0:   // Called by the GC after Soft Refs have been cleared to indicate
aoqi@0:   // that the request in _should_clear_all_soft_refs has been fulfilled.
aoqi@0:   void cleared_all_soft_refs();
aoqi@0: 
aoqi@0:   // Identification methods.
aoqi@0:   virtual GenCollectorPolicy*           as_generation_policy()            { return NULL; }
aoqi@0:   virtual TwoGenerationCollectorPolicy* as_two_generation_policy()        { return NULL; }
aoqi@0:   virtual MarkSweepPolicy*              as_mark_sweep_policy()            { return NULL; }
aoqi@0: #if INCLUDE_ALL_GCS
aoqi@0:   virtual ConcurrentMarkSweepPolicy*    as_concurrent_mark_sweep_policy() { return NULL; }
aoqi@0:   virtual G1CollectorPolicy*            as_g1_policy()                    { return NULL; }
aoqi@0: #endif // INCLUDE_ALL_GCS
aoqi@0:   // Note that these are not virtual.
aoqi@0:   bool is_generation_policy()            { return as_generation_policy() != NULL; }
aoqi@0:   bool is_two_generation_policy()        { return as_two_generation_policy() != NULL; }
aoqi@0:   bool is_mark_sweep_policy()            { return as_mark_sweep_policy() != NULL; }
aoqi@0: #if INCLUDE_ALL_GCS
aoqi@0:   bool is_concurrent_mark_sweep_policy() { return as_concurrent_mark_sweep_policy() != NULL; }
aoqi@0:   bool is_g1_policy()                    { return as_g1_policy() != NULL; }
aoqi@0: #else  // INCLUDE_ALL_GCS
aoqi@0:   bool is_concurrent_mark_sweep_policy() { return false; }
aoqi@0:   bool is_g1_policy()                    { return false; }
aoqi@0: #endif // INCLUDE_ALL_GCS
aoqi@0: 
aoqi@0: 
aoqi@0:   virtual BarrierSet::Name barrier_set_name() = 0;
aoqi@0: 
aoqi@0:   // Create the remembered set (to cover the given reserved region,
aoqi@0:   // allowing breaking up into at most "max_covered_regions").
aoqi@0:   virtual GenRemSet* create_rem_set(MemRegion reserved,
aoqi@0:                                     int max_covered_regions);
aoqi@0: 
aoqi@0:   // This method controls how a collector satisfies a request
aoqi@0:   // for a block of memory.  "gc_time_limit_was_exceeded" will
aoqi@0:   // be set to true if the adaptive size policy determine that
aoqi@0:   // an excessive amount of time is being spent doing collections
aoqi@0:   // and caused a NULL to be returned.  If a NULL is not returned,
aoqi@0:   // "gc_time_limit_was_exceeded" has an undefined meaning.
aoqi@0:   virtual HeapWord* mem_allocate_work(size_t size,
aoqi@0:                                       bool is_tlab,
aoqi@0:                                       bool* gc_overhead_limit_was_exceeded) = 0;
aoqi@0: 
aoqi@0:   // This method controls how a collector handles one or more
aoqi@0:   // of its generations being fully allocated.
aoqi@0:   virtual HeapWord *satisfy_failed_allocation(size_t size, bool is_tlab) = 0;
aoqi@0:   // This method controls how a collector handles a metadata allocation
aoqi@0:   // failure.
aoqi@0:   virtual MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
aoqi@0:                                                        size_t size,
aoqi@0:                                                        Metaspace::MetadataType mdtype);
aoqi@0: 
aoqi@0:   // Performace Counter support
aoqi@0:   GCPolicyCounters* counters()     { return _gc_policy_counters; }
aoqi@0: 
aoqi@0:   // Create the jstat counters for the GC policy.  By default, policy's
aoqi@0:   // don't have associated counters, and we complain if this is invoked.
aoqi@0:   virtual void initialize_gc_policy_counters() {
aoqi@0:     ShouldNotReachHere();
aoqi@0:   }
aoqi@0: 
aoqi@0:   virtual CollectorPolicy::Name kind() {
aoqi@0:     return CollectorPolicy::CollectorPolicyKind;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Returns true if a collector has eden space with soft end.
aoqi@0:   virtual bool has_soft_ended_eden() {
aoqi@0:     return false;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Do any updates required to global flags that are due to heap initialization
aoqi@0:   // changes
aoqi@0:   virtual void post_heap_initialize() = 0;
aoqi@0: };
aoqi@0: 
aoqi@0: class ClearedAllSoftRefs : public StackObj {
aoqi@0:   bool _clear_all_soft_refs;
aoqi@0:   CollectorPolicy* _collector_policy;
aoqi@0:  public:
aoqi@0:   ClearedAllSoftRefs(bool clear_all_soft_refs,
aoqi@0:                      CollectorPolicy* collector_policy) :
aoqi@0:     _clear_all_soft_refs(clear_all_soft_refs),
aoqi@0:     _collector_policy(collector_policy) {}
aoqi@0: 
aoqi@0:   ~ClearedAllSoftRefs() {
aoqi@0:     if (_clear_all_soft_refs) {
aoqi@0:       _collector_policy->cleared_all_soft_refs();
aoqi@0:     }
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: class GenCollectorPolicy : public CollectorPolicy {
aoqi@0: friend class TestGenCollectorPolicy;
aoqi@0:  protected:
aoqi@0:   size_t _min_gen0_size;
aoqi@0:   size_t _initial_gen0_size;
aoqi@0:   size_t _max_gen0_size;
aoqi@0: 
aoqi@0:   // _gen_alignment and _space_alignment will have the same value most of the
aoqi@0:   // time. When using large pages they can differ.
aoqi@0:   size_t _gen_alignment;
aoqi@0: 
aoqi@0:   GenerationSpec **_generations;
aoqi@0: 
aoqi@0:   // Return true if an allocation should be attempted in the older
aoqi@0:   // generation if it fails in the younger generation.  Return
aoqi@0:   // false, otherwise.
aoqi@0:   virtual bool should_try_older_generation_allocation(size_t word_size) const;
aoqi@0: 
aoqi@0:   void initialize_flags();
aoqi@0:   void initialize_size_info();
aoqi@0: 
aoqi@0:   DEBUG_ONLY(void assert_flags();)
aoqi@0:   DEBUG_ONLY(void assert_size_info();)
aoqi@0: 
aoqi@0:   // Try to allocate space by expanding the heap.
aoqi@0:   virtual HeapWord* expand_heap_and_allocate(size_t size, bool is_tlab);
aoqi@0: 
aoqi@0:   // Compute max heap alignment
aoqi@0:   size_t compute_max_alignment();
aoqi@0: 
aoqi@0:  // Scale the base_size by NewRatio according to
aoqi@0:  //     result = base_size / (NewRatio + 1)
aoqi@0:  // and align by min_alignment()
aoqi@0:  size_t scale_by_NewRatio_aligned(size_t base_size);
aoqi@0: 
aoqi@0:  // Bound the value by the given maximum minus the min_alignment
aoqi@0:  size_t bound_minus_alignment(size_t desired_size, size_t maximum_size);
aoqi@0: 
aoqi@0:  public:
aoqi@0:   GenCollectorPolicy();
aoqi@0: 
aoqi@0:   // Accessors
aoqi@0:   size_t min_gen0_size()     { return _min_gen0_size; }
aoqi@0:   size_t initial_gen0_size() { return _initial_gen0_size; }
aoqi@0:   size_t max_gen0_size()     { return _max_gen0_size; }
aoqi@0:   size_t gen_alignment()     { return _gen_alignment; }
aoqi@0: 
aoqi@0:   virtual int number_of_generations() = 0;
aoqi@0: 
aoqi@0:   virtual GenerationSpec **generations() {
aoqi@0:     assert(_generations != NULL, "Sanity check");
aoqi@0:     return _generations;
aoqi@0:   }
aoqi@0: 
aoqi@0:   virtual GenCollectorPolicy* as_generation_policy() { return this; }
aoqi@0: 
aoqi@0:   virtual void initialize_generations() { };
aoqi@0: 
aoqi@0:   virtual void initialize_all() {
aoqi@0:     CollectorPolicy::initialize_all();
aoqi@0:     initialize_generations();
aoqi@0:   }
aoqi@0: 
aoqi@0:   size_t young_gen_size_lower_bound();
aoqi@0: 
aoqi@0:   HeapWord* mem_allocate_work(size_t size,
aoqi@0:                               bool is_tlab,
aoqi@0:                               bool* gc_overhead_limit_was_exceeded);
aoqi@0: 
aoqi@0:   HeapWord *satisfy_failed_allocation(size_t size, bool is_tlab);
aoqi@0: 
aoqi@0:   // Adaptive size policy
aoqi@0:   virtual void initialize_size_policy(size_t init_eden_size,
aoqi@0:                                       size_t init_promo_size,
aoqi@0:                                       size_t init_survivor_size);
aoqi@0: 
aoqi@0:   virtual void post_heap_initialize() {
aoqi@0:     assert(_max_gen0_size == MaxNewSize, "Should be taken care of by initialize_size_info");
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: // All of hotspot's current collectors are subtypes of this
aoqi@0: // class. Currently, these collectors all use the same gen[0],
aoqi@0: // but have different gen[1] types. If we add another subtype
aoqi@0: // of CollectorPolicy, this class should be broken out into
aoqi@0: // its own file.
aoqi@0: 
aoqi@0: class TwoGenerationCollectorPolicy : public GenCollectorPolicy {
aoqi@0:  protected:
aoqi@0:   size_t _min_gen1_size;
aoqi@0:   size_t _initial_gen1_size;
aoqi@0:   size_t _max_gen1_size;
aoqi@0: 
aoqi@0:   void initialize_flags();
aoqi@0:   void initialize_size_info();
aoqi@0: 
aoqi@0:   DEBUG_ONLY(void assert_flags();)
aoqi@0:   DEBUG_ONLY(void assert_size_info();)
aoqi@0: 
aoqi@0:  public:
aoqi@0:   TwoGenerationCollectorPolicy() : GenCollectorPolicy(), _min_gen1_size(0),
aoqi@0:     _initial_gen1_size(0), _max_gen1_size(0) {}
aoqi@0: 
aoqi@0:   // Accessors
aoqi@0:   size_t min_gen1_size()     { return _min_gen1_size; }
aoqi@0:   size_t initial_gen1_size() { return _initial_gen1_size; }
aoqi@0:   size_t max_gen1_size()     { return _max_gen1_size; }
aoqi@0: 
aoqi@0:   // Inherited methods
aoqi@0:   TwoGenerationCollectorPolicy* as_two_generation_policy() { return this; }
aoqi@0: 
aoqi@0:   int number_of_generations()          { return 2; }
aoqi@0:   BarrierSet::Name barrier_set_name()  { return BarrierSet::CardTableModRef; }
aoqi@0: 
aoqi@0:   virtual CollectorPolicy::Name kind() {
aoqi@0:     return CollectorPolicy::TwoGenerationCollectorPolicyKind;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Returns true if gen0 sizes were adjusted
aoqi@0:   bool adjust_gen0_sizes(size_t* gen0_size_ptr, size_t* gen1_size_ptr,
aoqi@0:                          const size_t heap_size);
aoqi@0: };
aoqi@0: 
aoqi@0: class MarkSweepPolicy : public TwoGenerationCollectorPolicy {
aoqi@0:  protected:
aoqi@0:   void initialize_alignments();
aoqi@0:   void initialize_generations();
aoqi@0: 
aoqi@0:  public:
aoqi@0:   MarkSweepPolicy() {}
aoqi@0: 
aoqi@0:   MarkSweepPolicy* as_mark_sweep_policy() { return this; }
aoqi@0: 
aoqi@0:   void initialize_gc_policy_counters();
aoqi@0: };
aoqi@0: 
aoqi@0: #endif // SHARE_VM_MEMORY_COLLECTORPOLICY_HPP