--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1ParScanThreadState.hpp Thu Jun 26 15:45:07 2014 +0200
@@ -0,0 +1,292 @@
+/*
+ * Copyright (c) 2014, 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_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP
+
+#include "gc_implementation/g1/dirtyCardQueue.hpp"
+#include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
+#include "gc_implementation/g1/g1CollectedHeap.hpp"
+#include "gc_implementation/g1/g1CollectorPolicy.hpp"
+#include "gc_implementation/g1/g1OopClosures.hpp"
+#include "gc_implementation/g1/g1RemSet.hpp"
+#include "gc_implementation/shared/ageTable.hpp"
+#include "memory/allocation.hpp"
+#include "oops/oop.hpp"
+
+class HeapRegion;
+class outputStream;
+
+class G1ParScanThreadState : public StackObj {
+protected:
+ G1CollectedHeap* _g1h;
+ RefToScanQueue* _refs;
+ DirtyCardQueue _dcq;
+ G1SATBCardTableModRefBS* _ct_bs;
+ G1RemSet* _g1_rem;
+
+ G1ParGCAllocBuffer _surviving_alloc_buffer;
+ G1ParGCAllocBuffer _tenured_alloc_buffer;
+ G1ParGCAllocBuffer* _alloc_buffers[GCAllocPurposeCount];
+ ageTable _age_table;
+
+ G1ParScanClosure _scanner;
+
+ size_t _alloc_buffer_waste;
+ size_t _undo_waste;
+
+ OopsInHeapRegionClosure* _evac_failure_cl;
+
+ int _hash_seed;
+ uint _queue_num;
+
+ size_t _term_attempts;
+
+ double _start;
+ double _start_strong_roots;
+ double _strong_roots_time;
+ double _start_term;
+ double _term_time;
+
+ // Map from young-age-index (0 == not young, 1 is youngest) to
+ // surviving words. base is what we get back from the malloc call
+ size_t* _surviving_young_words_base;
+ // this points into the array, as we use the first few entries for padding
+ size_t* _surviving_young_words;
+
+#define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
+
+ void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; }
+
+ void add_to_undo_waste(size_t waste) { _undo_waste += waste; }
+
+ DirtyCardQueue& dirty_card_queue() { return _dcq; }
+ G1SATBCardTableModRefBS* ctbs() { return _ct_bs; }
+
+ template <class T> inline void immediate_rs_update(HeapRegion* from, T* p, int tid);
+
+ template <class T> void deferred_rs_update(HeapRegion* from, T* p, int tid) {
+ // If the new value of the field points to the same region or
+ // is the to-space, we don't need to include it in the Rset updates.
+ if (!from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) && !from->is_survivor()) {
+ size_t card_index = ctbs()->index_for(p);
+ // If the card hasn't been added to the buffer, do it.
+ if (ctbs()->mark_card_deferred(card_index)) {
+ dirty_card_queue().enqueue((jbyte*)ctbs()->byte_for_index(card_index));
+ }
+ }
+ }
+
+public:
+ G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp);
+ ~G1ParScanThreadState() {
+ retire_alloc_buffers();
+ FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base, mtGC);
+ }
+
+ RefToScanQueue* refs() { return _refs; }
+ ageTable* age_table() { return &_age_table; }
+
+ G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) {
+ return _alloc_buffers[purpose];
+ }
+
+ size_t alloc_buffer_waste() const { return _alloc_buffer_waste; }
+ size_t undo_waste() const { return _undo_waste; }
+
+#ifdef ASSERT
+ bool verify_ref(narrowOop* ref) const;
+ bool verify_ref(oop* ref) const;
+ bool verify_task(StarTask ref) const;
+#endif // ASSERT
+
+ template <class T> void push_on_queue(T* ref) {
+ assert(verify_ref(ref), "sanity");
+ refs()->push(ref);
+ }
+
+ template <class T> inline void update_rs(HeapRegion* from, T* p, int tid);
+
+ HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) {
+ HeapWord* obj = NULL;
+ size_t gclab_word_size = _g1h->desired_plab_sz(purpose);
+ if (word_sz * 100 < gclab_word_size * ParallelGCBufferWastePct) {
+ G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose);
+ add_to_alloc_buffer_waste(alloc_buf->words_remaining());
+ alloc_buf->retire(false /* end_of_gc */, false /* retain */);
+
+ HeapWord* buf = _g1h->par_allocate_during_gc(purpose, gclab_word_size);
+ if (buf == NULL) return NULL; // Let caller handle allocation failure.
+ // Otherwise.
+ alloc_buf->set_word_size(gclab_word_size);
+ alloc_buf->set_buf(buf);
+
+ obj = alloc_buf->allocate(word_sz);
+ assert(obj != NULL, "buffer was definitely big enough...");
+ } else {
+ obj = _g1h->par_allocate_during_gc(purpose, word_sz);
+ }
+ return obj;
+ }
+
+ HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz) {
+ HeapWord* obj = alloc_buffer(purpose)->allocate(word_sz);
+ if (obj != NULL) return obj;
+ return allocate_slow(purpose, word_sz);
+ }
+
+ void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz) {
+ if (alloc_buffer(purpose)->contains(obj)) {
+ assert(alloc_buffer(purpose)->contains(obj + word_sz - 1),
+ "should contain whole object");
+ alloc_buffer(purpose)->undo_allocation(obj, word_sz);
+ } else {
+ CollectedHeap::fill_with_object(obj, word_sz);
+ add_to_undo_waste(word_sz);
+ }
+ }
+
+ void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) {
+ _evac_failure_cl = evac_failure_cl;
+ }
+ OopsInHeapRegionClosure* evac_failure_closure() {
+ return _evac_failure_cl;
+ }
+
+ int* hash_seed() { return &_hash_seed; }
+ uint queue_num() { return _queue_num; }
+
+ size_t term_attempts() const { return _term_attempts; }
+ void note_term_attempt() { _term_attempts++; }
+
+ void start_strong_roots() {
+ _start_strong_roots = os::elapsedTime();
+ }
+ void end_strong_roots() {
+ _strong_roots_time += (os::elapsedTime() - _start_strong_roots);
+ }
+ double strong_roots_time() const { return _strong_roots_time; }
+
+ void start_term_time() {
+ note_term_attempt();
+ _start_term = os::elapsedTime();
+ }
+ void end_term_time() {
+ _term_time += (os::elapsedTime() - _start_term);
+ }
+ double term_time() const { return _term_time; }
+
+ double elapsed_time() const {
+ return os::elapsedTime() - _start;
+ }
+
+ static void
+ print_termination_stats_hdr(outputStream* const st = gclog_or_tty);
+ void
+ print_termination_stats(int i, outputStream* const st = gclog_or_tty) const;
+
+ size_t* surviving_young_words() {
+ // We add on to hide entry 0 which accumulates surviving words for
+ // age -1 regions (i.e. non-young ones)
+ return _surviving_young_words;
+ }
+
+ private:
+ void retire_alloc_buffers() {
+ for (int ap = 0; ap < GCAllocPurposeCount; ++ap) {
+ size_t waste = _alloc_buffers[ap]->words_remaining();
+ add_to_alloc_buffer_waste(waste);
+ _alloc_buffers[ap]->flush_stats_and_retire(_g1h->stats_for_purpose((GCAllocPurpose)ap),
+ true /* end_of_gc */,
+ false /* retain */);
+ }
+ }
+
+ #define G1_PARTIAL_ARRAY_MASK 0x2
+
+ inline bool has_partial_array_mask(oop* ref) const {
+ return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
+ }
+
+ // We never encode partial array oops as narrowOop*, so return false immediately.
+ // This allows the compiler to create optimized code when popping references from
+ // the work queue.
+ inline bool has_partial_array_mask(narrowOop* ref) const {
+ assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
+ return false;
+ }
+
+ // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
+ // We always encode partial arrays as regular oop, to allow the
+ // specialization for has_partial_array_mask() for narrowOops above.
+ // This means that unintentional use of this method with narrowOops are caught
+ // by the compiler.
+ inline oop* set_partial_array_mask(oop obj) const {
+ assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
+ return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
+ }
+
+ inline oop clear_partial_array_mask(oop* ref) const {
+ return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
+ }
+
+ inline void do_oop_partial_array(oop* p);
+
+ // This method is applied to the fields of the objects that have just been copied.
+ template <class T> void do_oop_evac(T* p, HeapRegion* from) {
+ assert(!oopDesc::is_null(oopDesc::load_decode_heap_oop(p)),
+ "Reference should not be NULL here as such are never pushed to the task queue.");
+ oop obj = oopDesc::load_decode_heap_oop_not_null(p);
+
+ // Although we never intentionally push references outside of the collection
+ // set, due to (benign) races in the claim mechanism during RSet scanning more
+ // than one thread might claim the same card. So the same card may be
+ // processed multiple times. So redo this check.
+ if (_g1h->in_cset_fast_test(obj)) {
+ oop forwardee;
+ if (obj->is_forwarded()) {
+ forwardee = obj->forwardee();
+ } else {
+ forwardee = copy_to_survivor_space(obj);
+ }
+ assert(forwardee != NULL, "forwardee should not be NULL");
+ oopDesc::encode_store_heap_oop(p, forwardee);
+ }
+
+ assert(obj != NULL, "Must be");
+ update_rs(from, p, queue_num());
+ }
+public:
+
+ oop copy_to_survivor_space(oop const obj);
+
+ template <class T> inline void deal_with_reference(T* ref_to_scan);
+
+ inline void deal_with_reference(StarTask ref);
+
+public:
+ void trim_queue();
+};
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP