0N/A

0N/A

0N/Aclass BarrierSet;

0N/Aclass ThreadClosure;

0N/Aclass AdaptiveSizePolicy;

0N/Aclass Thread;

1387N/Aclass CollectorPolicy;

0N/A

0N/Aclass CollectedHeap : public CHeapObj {

0N/A friend class VMStructs;

0N/A friend class IsGCActiveMark; // Block structured external access to _is_gc_active

542N/A friend class constantPoolCacheKlass; // allocate() method inserts is_conc_safe

0N/A

0N/A#ifdef ASSERT

0N/A static int _fire_out_of_memory_count;

0N/A#endif

0N/A

481N/A // Used for filler objects (static, but initialized in ctor).

481N/A static size_t _filler_array_max_size;

481N/A

1166N/A // Used in support of ReduceInitialCardMarks; only consulted if COMPILER2 is being used

1166N/A bool _defer_initial_card_mark;

1166N/A

0N/A protected:

0N/A MemRegion _reserved;

0N/A BarrierSet* _barrier_set;

0N/A bool _is_gc_active;

1753N/A int _n_par_threads;

1753N/A

0N/A unsigned int _total_collections; // ... started

0N/A unsigned int _total_full_collections; // ... started

0N/A NOT_PRODUCT(volatile size_t _promotion_failure_alot_count;)

0N/A NOT_PRODUCT(volatile size_t _promotion_failure_alot_gc_number;)

0N/A

0N/A // Reason for current garbage collection. Should be set to

0N/A // a value reflecting no collection between collections.

0N/A GCCause::Cause _gc_cause;

0N/A GCCause::Cause _gc_lastcause;

0N/A PerfStringVariable* _perf_gc_cause;

0N/A PerfStringVariable* _perf_gc_lastcause;

0N/A

0N/A // Constructor

0N/A CollectedHeap();

0N/A

1166N/A // Do common initializations that must follow instance construction,

1166N/A // for example, those needing virtual calls.

1166N/A // This code could perhaps be moved into initialize() but would

1166N/A // be slightly more awkward because we want the latter to be a

1166N/A // pure virtual.

1166N/A void pre_initialize();

1166N/A

0N/A // Create a new tlab

0N/A virtual HeapWord* allocate_new_tlab(size_t size);

0N/A

0N/A // Accumulate statistics on all tlabs.

0N/A virtual void accumulate_statistics_all_tlabs();

0N/A

0N/A // Reinitialize tlabs before resuming mutators.

0N/A virtual void resize_all_tlabs();

0N/A

0N/A protected:

0N/A // Allocate from the current thread's TLAB, with broken-out slow path.

0N/A inline static HeapWord* allocate_from_tlab(Thread* thread, size_t size);

0N/A static HeapWord* allocate_from_tlab_slow(Thread* thread, size_t size);

0N/A

0N/A // Allocate an uninitialized block of the given size, or returns NULL if

0N/A // this is impossible.

0N/A inline static HeapWord* common_mem_allocate_noinit(size_t size, bool is_noref, TRAPS);

0N/A

0N/A // Like allocate_init, but the block returned by a successful allocation

0N/A // is guaranteed initialized to zeros.

0N/A inline static HeapWord* common_mem_allocate_init(size_t size, bool is_noref, TRAPS);

0N/A

0N/A // Same as common_mem version, except memory is allocated in the permanent area

0N/A // If there is no permanent area, revert to common_mem_allocate_noinit

0N/A inline static HeapWord* common_permanent_mem_allocate_noinit(size_t size, TRAPS);

0N/A

0N/A // Same as common_mem version, except memory is allocated in the permanent area

0N/A // If there is no permanent area, revert to common_mem_allocate_init

0N/A inline static HeapWord* common_permanent_mem_allocate_init(size_t size, TRAPS);

0N/A

0N/A // Helper functions for (VM) allocation.

0N/A inline static void post_allocation_setup_common(KlassHandle klass,

0N/A HeapWord* obj, size_t size);

0N/A inline static void post_allocation_setup_no_klass_install(KlassHandle klass,

0N/A HeapWord* objPtr,

0N/A size_t size);

0N/A

0N/A inline static void post_allocation_setup_obj(KlassHandle klass,

0N/A HeapWord* obj, size_t size);

0N/A

0N/A inline static void post_allocation_setup_array(KlassHandle klass,

0N/A HeapWord* obj, size_t size,

0N/A int length);

0N/A

0N/A // Clears an allocated object.

0N/A inline static void init_obj(HeapWord* obj, size_t size);

0N/A

481N/A // Filler object utilities.

481N/A static inline size_t filler_array_hdr_size();

481N/A static inline size_t filler_array_min_size();

481N/A static inline size_t filler_array_max_size();

481N/A

481N/A DEBUG_ONLY(static void fill_args_check(HeapWord* start, size_t words);)

1165N/A DEBUG_ONLY(static void zap_filler_array(HeapWord* start, size_t words, bool zap = true);)

481N/A

481N/A // Fill with a single array; caller must ensure filler_array_min_size() <=

481N/A // words <= filler_array_max_size().

1165N/A static inline void fill_with_array(HeapWord* start, size_t words, bool zap = true);

481N/A

481N/A // Fill with a single object (either an int array or a java.lang.Object).

1165N/A static inline void fill_with_object_impl(HeapWord* start, size_t words, bool zap = true);

481N/A

0N/A // Verification functions

0N/A virtual void check_for_bad_heap_word_value(HeapWord* addr, size_t size)

0N/A PRODUCT_RETURN;

0N/A virtual void check_for_non_bad_heap_word_value(HeapWord* addr, size_t size)

0N/A PRODUCT_RETURN;

542N/A debug_only(static void check_for_valid_allocation_state();)

0N/A

0N/A public:

0N/A enum Name {

0N/A Abstract,

0N/A SharedHeap,

0N/A GenCollectedHeap,

0N/A ParallelScavengeHeap,

0N/A G1CollectedHeap

0N/A };

0N/A

0N/A virtual CollectedHeap::Name kind() const { return CollectedHeap::Abstract; }

0N/A

0N/A /**

0N/A virtual jint initialize() = 0;

0N/A

0N/A // In many heaps, there will be a need to perform some initialization activities

0N/A // after the Universe is fully formed, but before general heap allocation is allowed.

0N/A // This is the correct place to place such initialization methods.

0N/A virtual void post_initialize() = 0;

0N/A

0N/A MemRegion reserved_region() const { return _reserved; }

113N/A address base() const { return (address)reserved_region().start(); }

0N/A

0N/A // Future cleanup here. The following functions should specify bytes or

0N/A // heapwords as part of their signature.

0N/A virtual size_t capacity() const = 0;

0N/A virtual size_t used() const = 0;

0N/A

0N/A // Return "true" if the part of the heap that allocates Java

0N/A // objects has reached the maximal committed limit that it can

0N/A // reach, without a garbage collection.

0N/A virtual bool is_maximal_no_gc() const = 0;

0N/A

0N/A virtual size_t permanent_capacity() const = 0;

0N/A virtual size_t permanent_used() const = 0;

0N/A

0N/A // Support for java.lang.Runtime.maxMemory(): return the maximum amount of

0N/A // memory that the vm could make available for storing 'normal' java objects.

0N/A // This is based on the reserved address space, but should not include space

0N/A // that the vm uses internally for bookkeeping or temporary storage (e.g.,

0N/A // perm gen space or, in the case of the young gen, one of the survivor

0N/A // spaces).

0N/A virtual size_t max_capacity() const = 0;

0N/A

0N/A // Returns "TRUE" if "p" points into the reserved area of the heap.

0N/A bool is_in_reserved(const void* p) const {

0N/A return _reserved.contains(p);

0N/A }

0N/A

0N/A bool is_in_reserved_or_null(const void* p) const {

0N/A return p == NULL || is_in_reserved(p);

0N/A }

0N/A

0N/A // Returns "TRUE" if "p" points to the head of an allocated object in the

0N/A // heap. Since this method can be expensive in general, we restrict its

0N/A // use to assertion checking only.

0N/A virtual bool is_in(const void* p) const = 0;

0N/A

0N/A bool is_in_or_null(const void* p) const {

0N/A return p == NULL || is_in(p);

0N/A }

0N/A

0N/A // Let's define some terms: a "closed" subset of a heap is one that

0N/A //

0N/A // 1) contains all currently-allocated objects, and

0N/A //

0N/A // 2) is closed under reference: no object in the closed subset

0N/A // references one outside the closed subset.

0N/A //

0N/A // Membership in a heap's closed subset is useful for assertions.

0N/A // Clearly, the entire heap is a closed subset, so the default

0N/A // implementation is to use "is_in_reserved". But this may not be too

0N/A // liberal to perform useful checking. Also, the "is_in" predicate

0N/A // defines a closed subset, but may be too expensive, since "is_in"

0N/A // verifies that its argument points to an object head. The

0N/A // "closed_subset" method allows a heap to define an intermediate

0N/A // predicate, allowing more precise checking than "is_in_reserved" at

0N/A // lower cost than "is_in."

0N/A

0N/A // One important case is a heap composed of disjoint contiguous spaces,

0N/A // such as the Garbage-First collector. Such heaps have a convenient

0N/A // closed subset consisting of the allocated portions of those

0N/A // contiguous spaces.

0N/A

0N/A // Return "TRUE" iff the given pointer points into the heap's defined

0N/A // closed subset (which defaults to the entire heap).

0N/A virtual bool is_in_closed_subset(const void* p) const {

0N/A return is_in_reserved(p);

0N/A }

0N/A

0N/A bool is_in_closed_subset_or_null(const void* p) const {

0N/A return p == NULL || is_in_closed_subset(p);

0N/A }

0N/A

941N/A // XXX is_permanent() and is_in_permanent() should be better named

941N/A // to distinguish one from the other.

941N/A

0N/A // Returns "TRUE" if "p" is allocated as "permanent" data.

0N/A // If the heap does not use "permanent" data, returns the same

0N/A // value is_in_reserved() would return.

0N/A // NOTE: this actually returns true if "p" is in reserved space

0N/A // for the space not that it is actually allocated (i.e. in committed

0N/A // space). If you need the more conservative answer use is_permanent().

0N/A virtual bool is_in_permanent(const void *p) const = 0;

0N/A

941N/A bool is_in_permanent_or_null(const void *p) const {

941N/A return p == NULL || is_in_permanent(p);

941N/A }

941N/A

0N/A // Returns "TRUE" if "p" is in the committed area of "permanent" data.

0N/A // If the heap does not use "permanent" data, returns the same

0N/A // value is_in() would return.

0N/A virtual bool is_permanent(const void *p) const = 0;

0N/A

941N/A bool is_permanent_or_null(const void *p) const {

941N/A return p == NULL || is_permanent(p);

0N/A }

0N/A

989N/A // An object is scavengable if its location may move during a scavenge.

989N/A // (A scavenge is a GC which is not a full GC.)

989N/A // Currently, this just means it is not perm (and not null).

989N/A // This could change if we rethink what's in perm-gen.

989N/A bool is_scavengable(const void *p) const {

989N/A return !is_in_permanent_or_null(p);

989N/A }

989N/A

0N/A // Returns "TRUE" if "p" is a method oop in the

0N/A // current heap, with high probability. This predicate

0N/A // is not stable, in general.

0N/A bool is_valid_method(oop p) const;

0N/A

0N/A void set_gc_cause(GCCause::Cause v) {

0N/A if (UsePerfData) {

0N/A _gc_lastcause = _gc_cause;

0N/A _perf_gc_lastcause->set_value(GCCause::to_string(_gc_lastcause));

0N/A _perf_gc_cause->set_value(GCCause::to_string(v));

0N/A }

0N/A _gc_cause = v;

0N/A }

0N/A GCCause::Cause gc_cause() { return _gc_cause; }

0N/A

1753N/A // Number of threads currently working on GC tasks.

1753N/A int n_par_threads() { return _n_par_threads; }

1753N/A

1753N/A // May be overridden to set additional parallelism.

1753N/A virtual void set_par_threads(int t) { _n_par_threads = t; };

1753N/A

0N/A // Preload classes into the shared portion of the heap, and then dump

0N/A // that data to a file so that it can be loaded directly by another

0N/A // VM (then terminate).

0N/A virtual void preload_and_dump(TRAPS) { ShouldNotReachHere(); }

0N/A

0N/A // General obj/array allocation facilities.

0N/A inline static oop obj_allocate(KlassHandle klass, int size, TRAPS);

0N/A inline static oop array_allocate(KlassHandle klass, int size, int length, TRAPS);

0N/A inline static oop large_typearray_allocate(KlassHandle klass, int size, int length, TRAPS);

0N/A

0N/A // Special obj/array allocation facilities.

0N/A // Some heaps may want to manage "permanent" data uniquely. These default

0N/A // to the general routines if the heap does not support such handling.

0N/A inline static oop permanent_obj_allocate(KlassHandle klass, int size, TRAPS);

0N/A // permanent_obj_allocate_no_klass_install() does not do the installation of

0N/A // the klass pointer in the newly created object (as permanent_obj_allocate()

0N/A // above does). This allows for a delay in the installation of the klass

0N/A // pointer that is needed during the create of klassKlass's. The

0N/A // method post_allocation_install_obj_klass() is used to install the

0N/A // klass pointer.

0N/A inline static oop permanent_obj_allocate_no_klass_install(KlassHandle klass,

0N/A int size,

0N/A TRAPS);

0N/A inline static void post_allocation_install_obj_klass(KlassHandle klass,

0N/A oop obj,

0N/A int size);

0N/A inline static oop permanent_array_allocate(KlassHandle klass, int size, int length, TRAPS);

0N/A

0N/A // Raw memory allocation facilities

0N/A // The obj and array allocate methods are covers for these methods.

0N/A // The permanent allocation method should default to mem_allocate if

0N/A // permanent memory isn't supported.

0N/A virtual HeapWord* mem_allocate(size_t size,

0N/A bool is_noref,

0N/A bool is_tlab,

0N/A bool* gc_overhead_limit_was_exceeded) = 0;

0N/A virtual HeapWord* permanent_mem_allocate(size_t size) = 0;

0N/A

0N/A // The boundary between a "large" and "small" array of primitives, in words.

0N/A virtual size_t large_typearray_limit() = 0;

0N/A

481N/A // Utilities for turning raw memory into filler objects.

481N/A //

481N/A // min_fill_size() is the smallest region that can be filled.

481N/A // fill_with_objects() can fill arbitrary-sized regions of the heap using

481N/A // multiple objects. fill_with_object() is for regions known to be smaller

481N/A // than the largest array of integers; it uses a single object to fill the

481N/A // region and has slightly less overhead.

481N/A static size_t min_fill_size() {

481N/A return size_t(align_object_size(oopDesc::header_size()));

481N/A }

481N/A

1165N/A static void fill_with_objects(HeapWord* start, size_t words, bool zap = true);

481N/A

1165N/A static void fill_with_object(HeapWord* start, size_t words, bool zap = true);

1165N/A static void fill_with_object(MemRegion region, bool zap = true) {

1165N/A fill_with_object(region.start(), region.word_size(), zap);

481N/A }

1165N/A static void fill_with_object(HeapWord* start, HeapWord* end, bool zap = true) {

1165N/A fill_with_object(start, pointer_delta(end, start), zap);

481N/A }

481N/A

0N/A // Some heaps may offer a contiguous region for shared non-blocking

0N/A // allocation, via inlined code (by exporting the address of the top and

0N/A // end fields defining the extent of the contiguous allocation region.)

0N/A

0N/A // This function returns "true" iff the heap supports this kind of

0N/A // allocation. (Default is "no".)

0N/A virtual bool supports_inline_contig_alloc() const {

0N/A return false;

0N/A }

0N/A // These functions return the addresses of the fields that define the

0N/A // boundaries of the contiguous allocation area. (These fields should be

0N/A // physically near to one another.)

0N/A virtual HeapWord** top_addr() const {

0N/A guarantee(false, "inline contiguous allocation not supported");

0N/A return NULL;

0N/A }

0N/A virtual HeapWord** end_addr() const {

0N/A guarantee(false, "inline contiguous allocation not supported");

0N/A return NULL;

0N/A }

0N/A

0N/A // Some heaps may be in an unparseable state at certain times between

0N/A // collections. This may be necessary for efficient implementation of

0N/A // certain allocation-related activities. Calling this function before

0N/A // attempting to parse a heap ensures that the heap is in a parsable

0N/A // state (provided other concurrent activity does not introduce

0N/A // unparsability). It is normally expected, therefore, that this

0N/A // method is invoked with the world stopped.

0N/A // NOTE: if you override this method, make sure you call

0N/A // super::ensure_parsability so that the non-generational

0N/A // part of the work gets done. See implementation of

0N/A // CollectedHeap::ensure_parsability and, for instance,

0N/A // that of GenCollectedHeap::ensure_parsability().

0N/A // The argument "retire_tlabs" controls whether existing TLABs

0N/A // are merely filled or also retired, thus preventing further

0N/A // allocation from them and necessitating allocation of new TLABs.

0N/A virtual void ensure_parsability(bool retire_tlabs);

0N/A

0N/A // Return an estimate of the maximum allocation that could be performed

0N/A // without triggering any collection or expansion activity. In a

0N/A // generational collector, for example, this is probably the largest

0N/A // allocation that could be supported (without expansion) in the youngest

0N/A // generation. It is "unsafe" because no locks are taken; the result

0N/A // should be treated as an approximation, not a guarantee, for use in

0N/A // heuristic resizing decisions.

0N/A virtual size_t unsafe_max_alloc() = 0;

0N/A

0N/A // Section on thread-local allocation buffers (TLABs)

0N/A // If the heap supports thread-local allocation buffers, it should override

0N/A // the following methods:

0N/A // Returns "true" iff the heap supports thread-local allocation buffers.

0N/A // The default is "no".

0N/A virtual bool supports_tlab_allocation() const {

0N/A return false;

0N/A }

0N/A // The amount of space available for thread-local allocation buffers.

0N/A virtual size_t tlab_capacity(Thread *thr) const {

0N/A guarantee(false, "thread-local allocation buffers not supported");

0N/A return 0;

0N/A }

0N/A // An estimate of the maximum allocation that could be performed

0N/A // for thread-local allocation buffers without triggering any

0N/A // collection or expansion activity.

0N/A virtual size_t unsafe_max_tlab_alloc(Thread *thr) const {

0N/A guarantee(false, "thread-local allocation buffers not supported");

0N/A return 0;

0N/A }

1027N/A

0N/A // Can a compiler initialize a new object without store barriers?

0N/A // This permission only extends from the creation of a new object

1027N/A // via a TLAB up to the first subsequent safepoint. If such permission

1027N/A // is granted for this heap type, the compiler promises to call

1027N/A // defer_store_barrier() below on any slow path allocation of

1027N/A // a new object for which such initializing store barriers will

1027N/A // have been elided.

342N/A virtual bool can_elide_tlab_store_barriers() const = 0;

342N/A

0N/A // If a compiler is eliding store barriers for TLAB-allocated objects,

0N/A // there is probably a corresponding slow path which can produce

0N/A // an object allocated anywhere. The compiler's runtime support

0N/A // promises to call this function on such a slow-path-allocated

0N/A // object before performing initializations that have elided

1027N/A // store barriers. Returns new_obj, or maybe a safer copy thereof.

1166N/A virtual oop new_store_pre_barrier(JavaThread* thread, oop new_obj);

1027N/A

1027N/A // Answers whether an initializing store to a new object currently

1166N/A // allocated at the given address doesn't need a store

1027N/A // barrier. Returns "true" if it doesn't need an initializing

1027N/A // store barrier; answers "false" if it does.

1027N/A virtual bool can_elide_initializing_store_barrier(oop new_obj) = 0;

1027N/A

1166N/A // If a compiler is eliding store barriers for TLAB-allocated objects,

1166N/A // we will be informed of a slow-path allocation by a call

1166N/A // to new_store_pre_barrier() above. Such a call precedes the

1166N/A // initialization of the object itself, and no post-store-barriers will

1166N/A // be issued. Some heap types require that the barrier strictly follows

1166N/A // the initializing stores. (This is currently implemented by deferring the

1166N/A // barrier until the next slow-path allocation or gc-related safepoint.)

1166N/A // This interface answers whether a particular heap type needs the card

1166N/A // mark to be thus strictly sequenced after the stores.

1166N/A virtual bool card_mark_must_follow_store() const = 0;

1166N/A

1027N/A // If the CollectedHeap was asked to defer a store barrier above,

1027N/A // this informs it to flush such a deferred store barrier to the

1027N/A // remembered set.

1027N/A virtual void flush_deferred_store_barrier(JavaThread* thread);

0N/A

0N/A // Can a compiler elide a store barrier when it writes

0N/A // a permanent oop into the heap? Applies when the compiler

0N/A // is storing x to the heap, where x->is_perm() is true.

342N/A virtual bool can_elide_permanent_oop_store_barriers() const = 0;

0N/A

0N/A // Does this heap support heap inspection (+PrintClassHistogram?)

342N/A virtual bool supports_heap_inspection() const = 0;

0N/A

0N/A // Perform a collection of the heap; intended for use in implementing

0N/A // "System.gc". This probably implies as full a collection as the

0N/A // "CollectedHeap" supports.

0N/A virtual void collect(GCCause::Cause cause) = 0;

0N/A

0N/A // This interface assumes that it's being called by the

0N/A // vm thread. It collects the heap assuming that the

0N/A // heap lock is already held and that we are executing in

0N/A // the context of the vm thread.

0N/A virtual void collect_as_vm_thread(GCCause::Cause cause) = 0;

0N/A

0N/A // Returns the barrier set for this heap

0N/A BarrierSet* barrier_set() { return _barrier_set; }

0N/A

0N/A // Returns "true" iff there is a stop-world GC in progress. (I assume

0N/A // that it should answer "false" for the concurrent part of a concurrent

0N/A // collector -- dld).

0N/A bool is_gc_active() const { return _is_gc_active; }

0N/A

0N/A // Total number of GC collections (started)

0N/A unsigned int total_collections() const { return _total_collections; }

0N/A unsigned int total_full_collections() const { return _total_full_collections;}

0N/A

0N/A // Increment total number of GC collections (started)

0N/A // Should be protected but used by PSMarkSweep - cleanup for 1.4.2

0N/A void increment_total_collections(bool full = false) {

0N/A _total_collections++;

0N/A if (full) {

0N/A increment_total_full_collections();

0N/A }

0N/A }

0N/A

0N/A void increment_total_full_collections() { _total_full_collections++; }

0N/A

0N/A // Return the AdaptiveSizePolicy for the heap.

0N/A virtual AdaptiveSizePolicy* size_policy() = 0;

0N/A

1387N/A // Return the CollectorPolicy for the heap

1387N/A virtual CollectorPolicy* collector_policy() const = 0;

1387N/A

0N/A // Iterate over all the ref-containing fields of all objects, calling

0N/A // "cl.do_oop" on each. This includes objects in permanent memory.

0N/A virtual void oop_iterate(OopClosure* cl) = 0;

0N/A

0N/A // Iterate over all objects, calling "cl.do_object" on each.

0N/A // This includes objects in permanent memory.

0N/A virtual void object_iterate(ObjectClosure* cl) = 0;

0N/A

517N/A // Similar to object_iterate() except iterates only

517N/A // over live objects.

517N/A virtual void safe_object_iterate(ObjectClosure* cl) = 0;

517N/A

0N/A // Behaves the same as oop_iterate, except only traverses

0N/A // interior pointers contained in permanent memory. If there

0N/A // is no permanent memory, does nothing.

0N/A virtual void permanent_oop_iterate(OopClosure* cl) = 0;

0N/A

0N/A // Behaves the same as object_iterate, except only traverses

0N/A // object contained in permanent memory. If there is no

0N/A // permanent memory, does nothing.

0N/A virtual void permanent_object_iterate(ObjectClosure* cl) = 0;

0N/A

0N/A // NOTE! There is no requirement that a collector implement these

0N/A // functions.

0N/A //

0N/A // A CollectedHeap is divided into a dense sequence of "blocks"; that is,

0N/A // each address in the (reserved) heap is a member of exactly

0N/A // one block. The defining characteristic of a block is that it is

0N/A // possible to find its size, and thus to progress forward to the next

0N/A // block. (Blocks may be of different sizes.) Thus, blocks may

0N/A // represent Java objects, or they might be free blocks in a

0N/A // free-list-based heap (or subheap), as long as the two kinds are

0N/A // distinguishable and the size of each is determinable.

0N/A

0N/A // Returns the address of the start of the "block" that contains the

0N/A // address "addr". We say "blocks" instead of "object" since some heaps

0N/A // may not pack objects densely; a chunk may either be an object or a

0N/A // non-object.

0N/A virtual HeapWord* block_start(const void* addr) const = 0;

0N/A

0N/A // Requires "addr" to be the start of a chunk, and returns its size.

0N/A // "addr + size" is required to be the start of a new chunk, or the end

0N/A // of the active area of the heap.

0N/A virtual size_t block_size(const HeapWord* addr) const = 0;

0N/A

0N/A // Requires "addr" to be the start of a block, and returns "TRUE" iff

0N/A // the block is an object.

0N/A virtual bool block_is_obj(const HeapWord* addr) const = 0;

0N/A

0N/A // Returns the longest time (in ms) that has elapsed since the last

0N/A // time that any part of the heap was examined by a garbage collection.

0N/A virtual jlong millis_since_last_gc() = 0;

0N/A

0N/A // Perform any cleanup actions necessary before allowing a verification.

0N/A virtual void prepare_for_verify() = 0;

0N/A

615N/A // Generate any dumps preceding or following a full gc

615N/A void pre_full_gc_dump();

615N/A void post_full_gc_dump();

615N/A

0N/A virtual void print() const = 0;

0N/A virtual void print_on(outputStream* st) const = 0;

0N/A

0N/A // Print all GC threads (other than the VM thread)

0N/A // used by this heap.

0N/A virtual void print_gc_threads_on(outputStream* st) const = 0;

0N/A void print_gc_threads() { print_gc_threads_on(tty); }

0N/A // Iterator for all GC threads (other than VM thread)

0N/A virtual void gc_threads_do(ThreadClosure* tc) const = 0;

0N/A

0N/A // Print any relevant tracing info that flags imply.

0N/A // Default implementation does nothing.

0N/A virtual void print_tracing_info() const = 0;

0N/A

0N/A // Heap verification

845N/A virtual void verify(bool allow_dirty, bool silent, bool option) = 0;

0N/A

0N/A // Non product verification and debugging.

0N/A#ifndef PRODUCT

0N/A // Support for PromotionFailureALot. Return true if it's time to cause a

0N/A // promotion failure. The no-argument version uses

0N/A // this->_promotion_failure_alot_count as the counter.

0N/A inline bool promotion_should_fail(volatile size_t* count);

0N/A inline bool promotion_should_fail();

0N/A

0N/A // Reset the PromotionFailureALot counters. Should be called at the end of a

0N/A // GC in which promotion failure ocurred.

0N/A inline void reset_promotion_should_fail(volatile size_t* count);

0N/A inline void reset_promotion_should_fail();

0N/A#endif // #ifndef PRODUCT

0N/A

0N/A#ifdef ASSERT

0N/A static int fired_fake_oom() {

0N/A return (CIFireOOMAt > 1 && _fire_out_of_memory_count >= CIFireOOMAt);

0N/A }

0N/A#endif

1753N/A

1753N/A public:

1753N/A // This is a convenience method that is used in cases where

1753N/A // the actual number of GC worker threads is not pertinent but

1753N/A // only whether there more than 0. Use of this method helps

1753N/A // reduce the occurrence of ParallelGCThreads to uses where the

1753N/A // actual number may be germane.

1753N/A static bool use_parallel_gc_threads() { return ParallelGCThreads > 0; }

0N/A};

0N/A

0N/A

0N/Aclass GCCauseSetter : StackObj {

0N/A CollectedHeap* _heap;

0N/A GCCause::Cause _previous_cause;

0N/A public:

0N/A GCCauseSetter(CollectedHeap* heap, GCCause::Cause cause) {

0N/A assert(SafepointSynchronize::is_at_safepoint(),

0N/A "This method manipulates heap state without locking");

0N/A _heap = heap;

0N/A _previous_cause = _heap->gc_cause();

0N/A _heap->set_gc_cause(cause);

0N/A }

0N/A

0N/A ~GCCauseSetter() {

0N/A assert(SafepointSynchronize::is_at_safepoint(),

0N/A "This method manipulates heap state without locking");

0N/A _heap->set_gc_cause(_previous_cause);

0N/A }

0N/A};