truffle: src/share/vm/gc_implementation/g1/heapRegion.hpp comparison

comparison src/share/vm/gc_implementation/g1/heapRegion.hpp @ 342:37f87013dfd8

6711316: Open source the Garbage-First garbage collector Summary: First mercurial integration of the code for the Garbage-First garbage collector. Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr

author	ysr
date	Thu, 05 Jun 2008 15:57:56 -0700
parents
children	0edda524b58c

comparison

equal deleted inserted replaced

-:0b27f3512f9e
+:37f87013dfd8
+/*
+* Copyright 2001-2007 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.
+*
+*/
+#ifndef SERIALGC
+// A HeapRegion is the smallest piece of a G1CollectedHeap that
+// can be collected independently.
+// NOTE: Although a HeapRegion is a Space, its
+// Space::initDirtyCardClosure method must not be called.
+// The problem is that the existence of this method breaks
+// the independence of barrier sets from remembered sets.
+// The solution is to remove this method from the definition
+// of a Space.
+class CompactibleSpace;
+class ContiguousSpace;
+class HeapRegionRemSet;
+class HeapRegionRemSetIterator;
+class HeapRegion;
+// A dirty card to oop closure for heap regions. It
+// knows how to get the G1 heap and how to use the bitmap
+// in the concurrent marker used by G1 to filter remembered
+// sets.
+class HeapRegionDCTOC : public ContiguousSpaceDCTOC {
+public:
+// Specification of possible DirtyCardToOopClosure filtering.
+enum FilterKind {
+NoFilterKind,
+IntoCSFilterKind,
+OutOfRegionFilterKind
+};
+protected:
+HeapRegion* _hr;
+FilterKind _fk;
+G1CollectedHeap* _g1;
+void walk_mem_region_with_cl(MemRegion mr,
+HeapWord* bottom, HeapWord* top,
+OopClosure* cl);
+// We don't specialize this for FilteringClosure; filtering is handled by
+// the "FilterKind" mechanism.  But we provide this to avoid a compiler
+// warning.
+void walk_mem_region_with_cl(MemRegion mr,
+HeapWord* bottom, HeapWord* top,
+FilteringClosure* cl) {
+HeapRegionDCTOC::walk_mem_region_with_cl(mr, bottom, top,
+(OopClosure*)cl);
+}
+// Get the actual top of the area on which the closure will
+// operate, given where the top is assumed to be (the end of the
+// memory region passed to do_MemRegion) and where the object
+// at the top is assumed to start. For example, an object may
+// start at the top but actually extend past the assumed top,
+// in which case the top becomes the end of the object.
+HeapWord* get_actual_top(HeapWord* top, HeapWord* top_obj) {
+return ContiguousSpaceDCTOC::get_actual_top(top, top_obj);
+}
+// Walk the given memory region from bottom to (actual) top
+// looking for objects and applying the oop closure (_cl) to
+// them. The base implementation of this treats the area as
+// blocks, where a block may or may not be an object. Sub-
+// classes should override this to provide more accurate
+// or possibly more efficient walking.
+void walk_mem_region(MemRegion mr, HeapWord* bottom, HeapWord* top) {
+Filtering_DCTOC::walk_mem_region(mr, bottom, top);
+}
+public:
+HeapRegionDCTOC(G1CollectedHeap* g1,
+HeapRegion* hr, OopClosure* cl,
+CardTableModRefBS::PrecisionStyle precision,
+FilterKind fk);
+};
+// The complicating factor is that BlockOffsetTable diverged
+// significantly, and we need functionality that is only in the G1 version.
+// So I copied that code, which led to an alternate G1 version of
+// OffsetTableContigSpace.  If the two versions of BlockOffsetTable could
+// be reconciled, then G1OffsetTableContigSpace could go away.
+// The idea behind time stamps is the following. Doing a save_marks on
+// all regions at every GC pause is time consuming (if I remember
+// well, 10ms or so). So, we would like to do that only for regions
+// that are GC alloc regions. To achieve this, we use time
+// stamps. For every evacuation pause, G1CollectedHeap generates a
+// unique time stamp (essentially a counter that gets
+// incremented). Every time we want to call save_marks on a region,
+// we set the saved_mark_word to top and also copy the current GC
+// time stamp to the time stamp field of the space. Reading the
+// saved_mark_word involves checking the time stamp of the
+// region. If it is the same as the current GC time stamp, then we
+// can safely read the saved_mark_word field, as it is valid. If the
+// time stamp of the region is not the same as the current GC time
+// stamp, then we instead read top, as the saved_mark_word field is
+// invalid. Time stamps (on the regions and also on the
+// G1CollectedHeap) are reset at every cleanup (we iterate over
+// the regions anyway) and at the end of a Full GC. The current scheme
+// that uses sequential unsigned ints will fail only if we have 4b
+// evacuation pauses between two cleanups, which is _highly_ unlikely.
+class G1OffsetTableContigSpace: public ContiguousSpace {
+friend class VMStructs;
+protected:
+G1BlockOffsetArrayContigSpace _offsets;
+Mutex _par_alloc_lock;
+volatile unsigned _gc_time_stamp;
+public:
+// Constructor.  If "is_zeroed" is true, the MemRegion "mr" may be
+// assumed to contain zeros.
+G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray,
+MemRegion mr, bool is_zeroed = false);
+void set_bottom(HeapWord* value);
+void set_end(HeapWord* value);
+virtual HeapWord* saved_mark_word() const;
+virtual void set_saved_mark();
+void reset_gc_time_stamp() { _gc_time_stamp = 0; }
+virtual void initialize(MemRegion mr, bool clear_space);
+virtual void clear();
+HeapWord* block_start(const void* p);
+HeapWord* block_start_const(const void* p) const;
+// Add offset table update.
+virtual HeapWord* allocate(size_t word_size);
+HeapWord* par_allocate(size_t word_size);
+// MarkSweep support phase3
+virtual HeapWord* initialize_threshold();
+virtual HeapWord* cross_threshold(HeapWord* start, HeapWord* end);
+virtual void print() const;
+};
+class HeapRegion: public G1OffsetTableContigSpace {
+friend class VMStructs;
+private:
+// The next filter kind that should be used for a "new_dcto_cl" call with
+// the "traditional" signature.
+HeapRegionDCTOC::FilterKind _next_fk;
+// Requires that the region "mr" be dense with objects, and begin and end
+// with an object.
+void oops_in_mr_iterate(MemRegion mr, OopClosure* cl);
+// The remembered set for this region.
+// (Might want to make this "inline" later, to avoid some alloc failure
+// issues.)
+HeapRegionRemSet* _rem_set;
+G1BlockOffsetArrayContigSpace* offsets() { return &_offsets; }
+protected:
+// If this region is a member of a HeapRegionSeq, the index in that
+// sequence, otherwise -1.
+int  _hrs_index;
+bool _humongous;         // starts or continues a humongous object
+bool _humongous_start;   // starts a humongous object
+// For a humongous region, region in which it starts.
+HeapRegion* _humongous_start_region;
+// For the start region of a humongous sequence, it's original end().
+HeapWord* _orig_end;
+// True iff the region is in current collection_set.
+bool _in_collection_set;
+// True iff the region is on the unclean list, waiting to be zero filled.
+bool _is_on_unclean_list;
+// True iff the region is on the free list, ready for allocation.
+bool _is_on_free_list;
+// Is this or has it been an allocation region in the current collection
+// pause.
+bool _is_gc_alloc_region;
+// True iff an attempt to evacuate an object in the region failed.
+bool _evacuation_failed;
+// A heap region may be a member one of a number of special subsets, each
+// represented as linked lists through the field below.  Currently, these
+// sets include:
+//   The collection set.
+//   The set of allocation regions used in a collection pause.
+//   Spaces that may contain gray objects.
+HeapRegion* _next_in_special_set;
+// next region in the young "generation" region set
+HeapRegion* _next_young_region;
+// For parallel heapRegion traversal.
+jint _claimed;
+// We use concurrent marking to determine the amount of live data
+// in each heap region.
+size_t _prev_marked_bytes;    // Bytes known to be live via last completed marking.
+size_t _next_marked_bytes;    // Bytes known to be live via in-progress marking.
+// See "sort_index" method.  -1 means is not in the array.
+int _sort_index;
+// Means it has (or at least had) a very large RS, and should not be
+// considered for membership in a collection set.
+enum PopularityState {
+NotPopular,
+PopularPending,
+Popular
+};
+PopularityState _popularity;
+// <PREDICTION>
+double _gc_efficiency;
+// </PREDICTION>
+enum YoungType {
+NotYoung,                   // a region is not young
+ScanOnly,                   // a region is young and scan-only
+Young,                      // a region is young
+Survivor                    // a region is young and it contains
+// survivor
+};
+YoungType _young_type;
+int  _young_index_in_cset;
+SurvRateGroup* _surv_rate_group;
+int  _age_index;
+// The start of the unmarked area. The unmarked area extends from this
+// word until the top and/or end of the region, and is the part
+// of the region for which no marking was done, i.e. objects may
+// have been allocated in this part since the last mark phase.
+// "prev" is the top at the start of the last completed marking.
+// "next" is the top at the start of the in-progress marking (if any.)
+HeapWord* _prev_top_at_mark_start;
+HeapWord* _next_top_at_mark_start;
+// If a collection pause is in progress, this is the top at the start
+// of that pause.
+// We've counted the marked bytes of objects below here.
+HeapWord* _top_at_conc_mark_count;
+void init_top_at_mark_start() {
+assert(_prev_marked_bytes == 0 &&
+_next_marked_bytes == 0,
+"Must be called after zero_marked_bytes.");
+HeapWord* bot = bottom();
+_prev_top_at_mark_start = bot;
+_next_top_at_mark_start = bot;
+_top_at_conc_mark_count = bot;
+}
+jint _zfs;  // A member of ZeroFillState.  Protected by ZF_lock.
+Thread* _zero_filler; // If _zfs is ZeroFilling, the thread that (last)
+// made it so.
+void set_young_type(YoungType new_type) {
+//assert(_young_type != new_type, "setting the same type" );
+// TODO: add more assertions here
+_young_type = new_type;
+}
+public:
+// If "is_zeroed" is "true", the region "mr" can be assumed to contain zeros.
+HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray,
+MemRegion mr, bool is_zeroed);
+enum SomePublicConstants {
+// HeapRegions are GrainBytes-aligned
+// and have sizes that are multiples of GrainBytes.
+LogOfHRGrainBytes = 20,
+LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize,
+GrainBytes = 1 << LogOfHRGrainBytes,
+GrainWords = 1 <<LogOfHRGrainWords,
+MaxAge = 2, NoOfAges = MaxAge+1
+};
+// Concurrent refinement requires contiguous heap regions (in which TLABs
+// might be allocated) to be zero-filled.  Each region therefore has a
+// zero-fill-state.
+enum ZeroFillState {
+NotZeroFilled,
+ZeroFilling,
+ZeroFilled,
+Allocated
+};
+// If this region is a member of a HeapRegionSeq, the index in that
+// sequence, otherwise -1.
+int hrs_index() const { return _hrs_index; }
+void set_hrs_index(int index) { _hrs_index = index; }
+// The number of bytes marked live in the region in the last marking phase.
+size_t marked_bytes()    { return _prev_marked_bytes; }
+// The number of bytes counted in the next marking.
+size_t next_marked_bytes() { return _next_marked_bytes; }
+// The number of bytes live wrt the next marking.
+size_t next_live_bytes() {
+return (top() - next_top_at_mark_start())
+* HeapWordSize
++ next_marked_bytes();
+}
+// A lower bound on the amount of garbage bytes in the region.
+size_t garbage_bytes() {
+size_t used_at_mark_start_bytes =
+(prev_top_at_mark_start() - bottom()) * HeapWordSize;
+assert(used_at_mark_start_bytes >= marked_bytes(),
+"Can't mark more than we have.");
+return used_at_mark_start_bytes - marked_bytes();
+}
+// An upper bound on the number of live bytes in the region.
+size_t max_live_bytes() { return used() - garbage_bytes(); }
+void add_to_marked_bytes(size_t incr_bytes) {
+_next_marked_bytes = _next_marked_bytes + incr_bytes;
+guarantee( _next_marked_bytes <= used(), "invariant" );
+}
+void zero_marked_bytes()      {
+_prev_marked_bytes = _next_marked_bytes = 0;
+}
+bool isHumongous() const { return _humongous; }
+bool startsHumongous() const { return _humongous_start; }
+bool continuesHumongous() const { return _humongous && ! _humongous_start; }
+// For a humongous region, region in which it starts.
+HeapRegion* humongous_start_region() const {
+return _humongous_start_region;
+}
+// Causes the current region to represent a humongous object spanning "n"
+// regions.
+virtual void set_startsHumongous();
+// The regions that continue a humongous sequence should be added using
+// this method, in increasing address order.
+void set_continuesHumongous(HeapRegion* start);
+void add_continuingHumongousRegion(HeapRegion* cont);
+// If the region has a remembered set, return a pointer to it.
+HeapRegionRemSet* rem_set() const {
+return _rem_set;
+}
+// True iff the region is in current collection_set.
+bool in_collection_set() const {
+return _in_collection_set;
+}
+void set_in_collection_set(bool b) {
+_in_collection_set = b;
+}
+HeapRegion* next_in_collection_set() {
+assert(in_collection_set(), "should only invoke on member of CS.");
+assert(_next_in_special_set == NULL ||
+_next_in_special_set->in_collection_set(),
+"Malformed CS.");
+return _next_in_special_set;
+}
+void set_next_in_collection_set(HeapRegion* r) {
+assert(in_collection_set(), "should only invoke on member of CS.");
+assert(r == NULL || r->in_collection_set(), "Malformed CS.");
+_next_in_special_set = r;
+}
+// True iff it is or has been an allocation region in the current
+// collection pause.
+bool is_gc_alloc_region() const {
+return _is_gc_alloc_region;
+}
+void set_is_gc_alloc_region(bool b) {
+_is_gc_alloc_region = b;
+}
+HeapRegion* next_gc_alloc_region() {
+assert(is_gc_alloc_region(), "should only invoke on member of CS.");
+assert(_next_in_special_set == NULL ||
+_next_in_special_set->is_gc_alloc_region(),
+"Malformed CS.");
+return _next_in_special_set;
+}
+void set_next_gc_alloc_region(HeapRegion* r) {
+assert(is_gc_alloc_region(), "should only invoke on member of CS.");
+assert(r == NULL || r->is_gc_alloc_region(), "Malformed CS.");
+_next_in_special_set = r;
+}
+bool is_reserved() {
+return popular();
+}
+bool is_on_free_list() {
+return _is_on_free_list;
+}
+void set_on_free_list(bool b) {
+_is_on_free_list = b;
+}
+HeapRegion* next_from_free_list() {
+assert(is_on_free_list(),
+"Should only invoke on free space.");
+assert(_next_in_special_set == NULL ||
+_next_in_special_set->is_on_free_list(),
+"Malformed Free List.");
+return _next_in_special_set;
+}
+void set_next_on_free_list(HeapRegion* r) {
+assert(r == NULL || r->is_on_free_list(), "Malformed free list.");
+_next_in_special_set = r;
+}
+bool is_on_unclean_list() {
+return _is_on_unclean_list;
+}
+void set_on_unclean_list(bool b);
+HeapRegion* next_from_unclean_list() {
+assert(is_on_unclean_list(),
+"Should only invoke on unclean space.");
+assert(_next_in_special_set == NULL ||
+_next_in_special_set->is_on_unclean_list(),
+"Malformed unclean List.");
+return _next_in_special_set;
+}
+void set_next_on_unclean_list(HeapRegion* r);
+HeapRegion* get_next_young_region() { return _next_young_region; }
+void set_next_young_region(HeapRegion* hr) {
+_next_young_region = hr;
+}
+// Allows logical separation between objects allocated before and after.
+void save_marks();
+// Reset HR stuff to default values.
+void hr_clear(bool par, bool clear_space);
+void initialize(MemRegion mr, bool clear_space);
+// Ensure that "this" is zero-filled.
+void ensure_zero_filled();
+// This one requires that the calling thread holds ZF_mon.
+void ensure_zero_filled_locked();
+// Get the start of the unmarked area in this region.
+HeapWord* prev_top_at_mark_start() const { return _prev_top_at_mark_start; }
+HeapWord* next_top_at_mark_start() const { return _next_top_at_mark_start; }
+// Apply "cl->do_oop" to (the addresses of) all reference fields in objects
+// allocated in the current region before the last call to "save_mark".
+void oop_before_save_marks_iterate(OopClosure* cl);
+// This call determines the "filter kind" argument that will be used for
+// the next call to "new_dcto_cl" on this region with the "traditional"
+// signature (i.e., the call below.)  The default, in the absence of a
+// preceding call to this method, is "NoFilterKind", and a call to this
+// method is necessary for each such call, or else it reverts to the
+// default.
+// (This is really ugly, but all other methods I could think of changed a
+// lot of main-line code for G1.)
+void set_next_filter_kind(HeapRegionDCTOC::FilterKind nfk) {
+_next_fk = nfk;
+}
+DirtyCardToOopClosure*
+new_dcto_closure(OopClosure* cl,
+CardTableModRefBS::PrecisionStyle precision,
+HeapRegionDCTOC::FilterKind fk);
+#if WHASSUP
+DirtyCardToOopClosure*
+new_dcto_closure(OopClosure* cl,
+CardTableModRefBS::PrecisionStyle precision,
+HeapWord* boundary) {
+assert(boundary == NULL, "This arg doesn't make sense here.");
+DirtyCardToOopClosure* res = new_dcto_closure(cl, precision, _next_fk);
+_next_fk = HeapRegionDCTOC::NoFilterKind;
+return res;
+}
+#endif
+//
+// Note the start or end of marking. This tells the heap region
+// that the collector is about to start or has finished (concurrently)
+// marking the heap.
+//
+// Note the start of a marking phase. Record the
+// start of the unmarked area of the region here.
+void note_start_of_marking(bool during_initial_mark) {
+init_top_at_conc_mark_count();
+_next_marked_bytes = 0;
+if (during_initial_mark && is_young() && !is_survivor())
+_next_top_at_mark_start = bottom();
+else
+_next_top_at_mark_start = top();
+}
+// Note the end of a marking phase. Install the start of
+// the unmarked area that was captured at start of marking.
+void note_end_of_marking() {
+_prev_top_at_mark_start = _next_top_at_mark_start;
+_prev_marked_bytes = _next_marked_bytes;
+_next_marked_bytes = 0;
+guarantee(_prev_marked_bytes <=
+(size_t) (prev_top_at_mark_start() - bottom()) * HeapWordSize,
+"invariant");
+}
+// After an evacuation, we need to update _next_top_at_mark_start
+// to be the current top.  Note this is only valid if we have only
+// ever evacuated into this region.  If we evacuate, allocate, and
+// then evacuate we are in deep doodoo.
+void note_end_of_copying() {
+assert(top() >= _next_top_at_mark_start,
+"Increase only");
+_next_top_at_mark_start = top();
+}
+// Returns "false" iff no object in the region was allocated when the
+// last mark phase ended.
+bool is_marked() { return _prev_top_at_mark_start != bottom(); }
+// If "is_marked()" is true, then this is the index of the region in
+// an array constructed at the end of marking of the regions in a
+// "desirability" order.
+int sort_index() {
+return _sort_index;
+}
+void set_sort_index(int i) {
+_sort_index = i;
+}
+void init_top_at_conc_mark_count() {
+_top_at_conc_mark_count = bottom();
+}
+void set_top_at_conc_mark_count(HeapWord *cur) {
+assert(bottom() <= cur && cur <= end(), "Sanity.");
+_top_at_conc_mark_count = cur;
+}
+HeapWord* top_at_conc_mark_count() {
+return _top_at_conc_mark_count;
+}
+void reset_during_compaction() {
+guarantee( isHumongous() && startsHumongous(),
+"should only be called for humongous regions");
+zero_marked_bytes();
+init_top_at_mark_start();
+}
+bool popular() { return _popularity == Popular; }
+void set_popular(bool b) {
+if (b) {
+_popularity = Popular;
+} else {
+_popularity = NotPopular;
+}
+}
+bool popular_pending() { return _popularity == PopularPending; }
+void set_popular_pending(bool b) {
+if (b) {
+_popularity = PopularPending;
+} else {
+_popularity = NotPopular;
+}
+}
+// <PREDICTION>
+void calc_gc_efficiency(void);
+double gc_efficiency() { return _gc_efficiency;}
+// </PREDICTION>
+bool is_young() const     { return _young_type != NotYoung; }
+bool is_scan_only() const { return _young_type == ScanOnly; }
+bool is_survivor() const  { return _young_type == Survivor; }
+int  young_index_in_cset() const { return _young_index_in_cset; }
+void set_young_index_in_cset(int index) {
+assert( (index == -1) || is_young(), "pre-condition" );
+_young_index_in_cset = index;
+}
+int age_in_surv_rate_group() {
+assert( _surv_rate_group != NULL, "pre-condition" );
+assert( _age_index > -1, "pre-condition" );
+return _surv_rate_group->age_in_group(_age_index);
+}
+void recalculate_age_in_surv_rate_group() {
+assert( _surv_rate_group != NULL, "pre-condition" );
+assert( _age_index > -1, "pre-condition" );
+_age_index = _surv_rate_group->recalculate_age_index(_age_index);
+}
+void record_surv_words_in_group(size_t words_survived) {
+assert( _surv_rate_group != NULL, "pre-condition" );
+assert( _age_index > -1, "pre-condition" );
+int age_in_group = age_in_surv_rate_group();
+_surv_rate_group->record_surviving_words(age_in_group, words_survived);
+}
+int age_in_surv_rate_group_cond() {
+if (_surv_rate_group != NULL)
+return age_in_surv_rate_group();
+else
+return -1;
+}
+SurvRateGroup* surv_rate_group() {
+return _surv_rate_group;
+}
+void install_surv_rate_group(SurvRateGroup* surv_rate_group) {
+assert( surv_rate_group != NULL, "pre-condition" );
+assert( _surv_rate_group == NULL, "pre-condition" );
+assert( is_young(), "pre-condition" );
+_surv_rate_group = surv_rate_group;
+_age_index = surv_rate_group->next_age_index();
+}
+void uninstall_surv_rate_group() {
+if (_surv_rate_group != NULL) {
+assert( _age_index > -1, "pre-condition" );
+assert( is_young(), "pre-condition" );
+_surv_rate_group = NULL;
+_age_index = -1;
+} else {
+assert( _age_index == -1, "pre-condition" );
+}
+}
+void set_young() { set_young_type(Young); }
+void set_scan_only() { set_young_type(ScanOnly); }
+void set_survivor() { set_young_type(Survivor); }
+void set_not_young() { set_young_type(NotYoung); }
+// Determine if an object has been allocated since the last
+// mark performed by the collector. This returns true iff the object
+// is within the unmarked area of the region.
+bool obj_allocated_since_prev_marking(oop obj) const {
+return (HeapWord *) obj >= prev_top_at_mark_start();
+}
+bool obj_allocated_since_next_marking(oop obj) const {
+return (HeapWord *) obj >= next_top_at_mark_start();
+}
+// For parallel heapRegion traversal.
+bool claimHeapRegion(int claimValue);
+jint claim_value() { return _claimed; }
+// Use this carefully: only when you're sure no one is claiming...
+void set_claim_value(int claimValue) { _claimed = claimValue; }
+// Returns the "evacuation_failed" property of the region.
+bool evacuation_failed() { return _evacuation_failed; }
+// Sets the "evacuation_failed" property of the region.
+void set_evacuation_failed(bool b) {
+_evacuation_failed = b;
+if (b) {
+init_top_at_conc_mark_count();
+_next_marked_bytes = 0;
+}
+}
+// Requires that "mr" be entirely within the region.
+// Apply "cl->do_object" to all objects that intersect with "mr".
+// If the iteration encounters an unparseable portion of the region,
+// or if "cl->abort()" is true after a closure application,
+// terminate the iteration and return the address of the start of the
+// subregion that isn't done.  (The two can be distinguished by querying
+// "cl->abort()".)  Return of "NULL" indicates that the iteration
+// completed.
+HeapWord*
+object_iterate_mem_careful(MemRegion mr, ObjectClosure* cl);
+HeapWord*
+oops_on_card_seq_iterate_careful(MemRegion mr,
+FilterOutOfRegionClosure* cl);
+// The region "mr" is entirely in "this", and starts and ends at block
+// boundaries. The caller declares that all the contained blocks are
+// coalesced into one.
+void declare_filled_region_to_BOT(MemRegion mr) {
+_offsets.single_block(mr.start(), mr.end());
+}
+// A version of block start that is guaranteed to find *some* block
+// boundary at or before "p", but does not object iteration, and may
+// therefore be used safely when the heap is unparseable.
+HeapWord* block_start_careful(const void* p) const {
+return _offsets.block_start_careful(p);
+}
+// Requires that "addr" is within the region.  Returns the start of the
+// first ("careful") block that starts at or after "addr", or else the
+// "end" of the region if there is no such block.
+HeapWord* next_block_start_careful(HeapWord* addr);
+// Returns the zero-fill-state of the current region.
+ZeroFillState zero_fill_state() { return (ZeroFillState)_zfs; }
+bool zero_fill_is_allocated() { return _zfs == Allocated; }
+Thread* zero_filler() { return _zero_filler; }
+// Indicate that the contents of the region are unknown, and therefore
+// might require zero-filling.
+void set_zero_fill_needed() {
+set_zero_fill_state_work(NotZeroFilled);
+}
+void set_zero_fill_in_progress(Thread* t) {
+set_zero_fill_state_work(ZeroFilling);
+_zero_filler = t;
+}
+void set_zero_fill_complete();
+void set_zero_fill_allocated() {
+set_zero_fill_state_work(Allocated);
+}
+void set_zero_fill_state_work(ZeroFillState zfs);
+// This is called when a full collection shrinks the heap.
+// We want to set the heap region to a value which says
+// it is no longer part of the heap.  For now, we'll let "NotZF" fill
+// that role.
+void reset_zero_fill() {
+set_zero_fill_state_work(NotZeroFilled);
+_zero_filler = NULL;
+}
+#define HeapRegion_OOP_SINCE_SAVE_MARKS_DECL(OopClosureType, nv_suffix)  \
+virtual void oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl);
+SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DECL)
+CompactibleSpace* next_compaction_space() const;
+virtual void reset_after_compaction();
+void print() const;
+void print_on(outputStream* st) const;
+// Override
+virtual void verify(bool allow_dirty) const;
+#ifdef DEBUG
+HeapWord* allocate(size_t size);
+#endif
+};
+// HeapRegionClosure is used for iterating over regions.
+// Terminates the iteration when the "doHeapRegion" method returns "true".
+class HeapRegionClosure : public StackObj {
+friend class HeapRegionSeq;
+friend class G1CollectedHeap;
+bool _complete;
+void incomplete() { _complete = false; }
+public:
+HeapRegionClosure(): _complete(true) {}
+// Typically called on each region until it returns true.
+virtual bool doHeapRegion(HeapRegion* r) = 0;
+// True after iteration if the closure was applied to all heap regions
+// and returned "false" in all cases.
+bool complete() { return _complete; }
+};
+// A linked lists of heap regions.  It leaves the "next" field
+// unspecified; that's up to subtypes.
+class RegionList {
+protected:
+virtual HeapRegion* get_next(HeapRegion* chr) = 0;
+virtual void set_next(HeapRegion* chr,
+HeapRegion* new_next) = 0;
+HeapRegion* _hd;
+HeapRegion* _tl;
+size_t _sz;
+// Protected constructor because this type is only meaningful
+// when the _get/_set next functions are defined.
+RegionList() : _hd(NULL), _tl(NULL), _sz(0) {}
+public:
+void reset() {
+_hd = NULL;
+_tl = NULL;
+_sz = 0;
+}
+HeapRegion* hd() { return _hd; }
+HeapRegion* tl() { return _tl; }
+size_t sz() { return _sz; }
+size_t length();
+bool well_formed() {
+return
+((hd() == NULL && tl() == NULL && sz() == 0)
+|| (hd() != NULL && tl() != NULL && sz() > 0))
+&& (sz() == length());
+}
+virtual void insert_before_head(HeapRegion* r);
+void prepend_list(RegionList* new_list);
+virtual HeapRegion* pop();
+void dec_sz() { _sz--; }
+// Requires that "r" is an element of the list, and is not the tail.
+void delete_after(HeapRegion* r);
+};
+class EmptyNonHRegionList: public RegionList {
+protected:
+// Protected constructor because this type is only meaningful
+// when the _get/_set next functions are defined.
+EmptyNonHRegionList() : RegionList() {}
+public:
+void insert_before_head(HeapRegion* r) {
+//    assert(r->is_empty(), "Better be empty");
+assert(!r->isHumongous(), "Better not be humongous.");
+RegionList::insert_before_head(r);
+}
+void prepend_list(EmptyNonHRegionList* new_list) {
+//    assert(new_list->hd() == NULL || new_list->hd()->is_empty(),
+//     "Better be empty");
+assert(new_list->hd() == NULL || !new_list->hd()->isHumongous(),
+"Better not be humongous.");
+//    assert(new_list->tl() == NULL || new_list->tl()->is_empty(),
+//     "Better be empty");
+assert(new_list->tl() == NULL || !new_list->tl()->isHumongous(),
+"Better not be humongous.");
+RegionList::prepend_list(new_list);
+}
+};
+class UncleanRegionList: public EmptyNonHRegionList {
+public:
+HeapRegion* get_next(HeapRegion* hr) {
+return hr->next_from_unclean_list();
+}
+void set_next(HeapRegion* hr, HeapRegion* new_next) {
+hr->set_next_on_unclean_list(new_next);
+}
+UncleanRegionList() : EmptyNonHRegionList() {}
+void insert_before_head(HeapRegion* r) {
+assert(!r->is_on_free_list(),
+"Better not already be on free list");
+assert(!r->is_on_unclean_list(),
+"Better not already be on unclean list");
+r->set_zero_fill_needed();
+r->set_on_unclean_list(true);
+EmptyNonHRegionList::insert_before_head(r);
+}
+void prepend_list(UncleanRegionList* new_list) {
+assert(new_list->tl() == NULL || !new_list->tl()->is_on_free_list(),
+"Better not already be on free list");
+assert(new_list->tl() == NULL || new_list->tl()->is_on_unclean_list(),
+"Better already be marked as on unclean list");
+assert(new_list->hd() == NULL || !new_list->hd()->is_on_free_list(),
+"Better not already be on free list");
+assert(new_list->hd() == NULL || new_list->hd()->is_on_unclean_list(),
+"Better already be marked as on unclean list");
+EmptyNonHRegionList::prepend_list(new_list);
+}
+HeapRegion* pop() {
+HeapRegion* res = RegionList::pop();
+if (res != NULL) res->set_on_unclean_list(false);
+return res;
+}
+};
+// Local Variables: ***
+// c-indentation-style: gnu ***
+// End: ***
+#endif // SERIALGC

Mercurial > hg > truffle

comparison src/share/vm/gc_implementation/g1/heapRegion.hpp @ 342:37f87013dfd8