1.1 --- a/src/share/vm/gc_implementation/g1/g1ParScanThreadState.cpp Wed Mar 25 15:50:17 2015 +0100
1.2 +++ b/src/share/vm/gc_implementation/g1/g1ParScanThreadState.cpp Fri Dec 19 09:21:06 2014 +0100
1.3 @@ -38,6 +38,7 @@
1.4 _g1_rem(g1h->g1_rem_set()),
1.5 _hash_seed(17), _queue_num(queue_num),
1.6 _term_attempts(0),
1.7 + _tenuring_threshold(g1h->g1_policy()->tenuring_threshold()),
1.8 _age_table(false), _scanner(g1h, rp),
1.9 _strong_roots_time(0), _term_time(0) {
1.10 _scanner.set_par_scan_thread_state(this);
1.11 @@ -59,6 +60,12 @@
1.12
1.13 _g1_par_allocator = G1ParGCAllocator::create_allocator(_g1h);
1.14
1.15 + _dest[InCSetState::NotInCSet] = InCSetState::NotInCSet;
1.16 + // The dest for Young is used when the objects are aged enough to
1.17 + // need to be moved to the next space.
1.18 + _dest[InCSetState::Young] = InCSetState::Old;
1.19 + _dest[InCSetState::Old] = InCSetState::Old;
1.20 +
1.21 _start = os::elapsedTime();
1.22 }
1.23
1.24 @@ -150,52 +157,94 @@
1.25 } while (!_refs->is_empty());
1.26 }
1.27
1.28 -oop G1ParScanThreadState::copy_to_survivor_space(oop const old,
1.29 +HeapWord* G1ParScanThreadState::allocate_in_next_plab(InCSetState const state,
1.30 + InCSetState* dest,
1.31 + size_t word_sz,
1.32 + AllocationContext_t const context) {
1.33 + assert(state.is_in_cset_or_humongous(), err_msg("Unexpected state: " CSETSTATE_FORMAT, state.value()));
1.34 + assert(dest->is_in_cset_or_humongous(), err_msg("Unexpected dest: " CSETSTATE_FORMAT, dest->value()));
1.35 +
1.36 + // Right now we only have two types of regions (young / old) so
1.37 + // let's keep the logic here simple. We can generalize it when necessary.
1.38 + if (dest->is_young()) {
1.39 + HeapWord* const obj_ptr = _g1_par_allocator->allocate(InCSetState::Old,
1.40 + word_sz, context);
1.41 + if (obj_ptr == NULL) {
1.42 + return NULL;
1.43 + }
1.44 + // Make sure that we won't attempt to copy any other objects out
1.45 + // of a survivor region (given that apparently we cannot allocate
1.46 + // any new ones) to avoid coming into this slow path.
1.47 + _tenuring_threshold = 0;
1.48 + dest->set_old();
1.49 + return obj_ptr;
1.50 + } else {
1.51 + assert(dest->is_old(), err_msg("Unexpected dest: " CSETSTATE_FORMAT, dest->value()));
1.52 + // no other space to try.
1.53 + return NULL;
1.54 + }
1.55 +}
1.56 +
1.57 +InCSetState G1ParScanThreadState::next_state(InCSetState const state, markOop const m, uint& age) {
1.58 + if (state.is_young()) {
1.59 + age = !m->has_displaced_mark_helper() ? m->age()
1.60 + : m->displaced_mark_helper()->age();
1.61 + if (age < _tenuring_threshold) {
1.62 + return state;
1.63 + }
1.64 + }
1.65 + return dest(state);
1.66 +}
1.67 +
1.68 +oop G1ParScanThreadState::copy_to_survivor_space(InCSetState const state,
1.69 + oop const old,
1.70 markOop const old_mark) {
1.71 - size_t word_sz = old->size();
1.72 - HeapRegion* from_region = _g1h->heap_region_containing_raw(old);
1.73 + const size_t word_sz = old->size();
1.74 + HeapRegion* const from_region = _g1h->heap_region_containing_raw(old);
1.75 // +1 to make the -1 indexes valid...
1.76 - int young_index = from_region->young_index_in_cset()+1;
1.77 + const int young_index = from_region->young_index_in_cset()+1;
1.78 assert( (from_region->is_young() && young_index > 0) ||
1.79 (!from_region->is_young() && young_index == 0), "invariant" );
1.80 - G1CollectorPolicy* g1p = _g1h->g1_policy();
1.81 - uint age = old_mark->has_displaced_mark_helper() ? old_mark->displaced_mark_helper()->age()
1.82 - : old_mark->age();
1.83 - GCAllocPurpose alloc_purpose = g1p->evacuation_destination(from_region, age,
1.84 - word_sz);
1.85 - AllocationContext_t context = from_region->allocation_context();
1.86 - HeapWord* obj_ptr = _g1_par_allocator->allocate(alloc_purpose, word_sz, context);
1.87 + const AllocationContext_t context = from_region->allocation_context();
1.88 +
1.89 + uint age = 0;
1.90 + InCSetState dest_state = next_state(state, old_mark, age);
1.91 + HeapWord* obj_ptr = _g1_par_allocator->plab_allocate(dest_state, word_sz, context);
1.92 +
1.93 + // PLAB allocations should succeed most of the time, so we'll
1.94 + // normally check against NULL once and that's it.
1.95 + if (obj_ptr == NULL) {
1.96 + obj_ptr = _g1_par_allocator->allocate_direct_or_new_plab(dest_state, word_sz, context);
1.97 + if (obj_ptr == NULL) {
1.98 + obj_ptr = allocate_in_next_plab(state, &dest_state, word_sz, context);
1.99 + if (obj_ptr == NULL) {
1.100 + // This will either forward-to-self, or detect that someone else has
1.101 + // installed a forwarding pointer.
1.102 + return _g1h->handle_evacuation_failure_par(this, old);
1.103 + }
1.104 + }
1.105 + }
1.106 +
1.107 + assert(obj_ptr != NULL, "when we get here, allocation should have succeeded");
1.108 #ifndef PRODUCT
1.109 // Should this evacuation fail?
1.110 if (_g1h->evacuation_should_fail()) {
1.111 - if (obj_ptr != NULL) {
1.112 - _g1_par_allocator->undo_allocation(alloc_purpose, obj_ptr, word_sz, context);
1.113 - obj_ptr = NULL;
1.114 - }
1.115 + // Doing this after all the allocation attempts also tests the
1.116 + // undo_allocation() method too.
1.117 + _g1_par_allocator->undo_allocation(dest_state, obj_ptr, word_sz, context);
1.118 + return _g1h->handle_evacuation_failure_par(this, old);
1.119 }
1.120 #endif // !PRODUCT
1.121
1.122 - if (obj_ptr == NULL) {
1.123 - // This will either forward-to-self, or detect that someone else has
1.124 - // installed a forwarding pointer.
1.125 - return _g1h->handle_evacuation_failure_par(this, old);
1.126 - }
1.127 -
1.128 - oop obj = oop(obj_ptr);
1.129 -
1.130 // We're going to allocate linearly, so might as well prefetch ahead.
1.131 Prefetch::write(obj_ptr, PrefetchCopyIntervalInBytes);
1.132
1.133 - oop forward_ptr = old->forward_to_atomic(obj);
1.134 + const oop obj = oop(obj_ptr);
1.135 + const oop forward_ptr = old->forward_to_atomic(obj);
1.136 if (forward_ptr == NULL) {
1.137 Copy::aligned_disjoint_words((HeapWord*) old, obj_ptr, word_sz);
1.138
1.139 - // alloc_purpose is just a hint to allocate() above, recheck the type of region
1.140 - // we actually allocated from and update alloc_purpose accordingly
1.141 - HeapRegion* to_region = _g1h->heap_region_containing_raw(obj_ptr);
1.142 - alloc_purpose = to_region->is_young() ? GCAllocForSurvived : GCAllocForTenured;
1.143 -
1.144 - if (g1p->track_object_age(alloc_purpose)) {
1.145 + if (dest_state.is_young()) {
1.146 if (age < markOopDesc::max_age) {
1.147 age++;
1.148 }
1.149 @@ -215,13 +264,19 @@
1.150 }
1.151
1.152 if (G1StringDedup::is_enabled()) {
1.153 - G1StringDedup::enqueue_from_evacuation(from_region->is_young(),
1.154 - to_region->is_young(),
1.155 + const bool is_from_young = state.is_young();
1.156 + const bool is_to_young = dest_state.is_young();
1.157 + assert(is_from_young == _g1h->heap_region_containing_raw(old)->is_young(),
1.158 + "sanity");
1.159 + assert(is_to_young == _g1h->heap_region_containing_raw(obj)->is_young(),
1.160 + "sanity");
1.161 + G1StringDedup::enqueue_from_evacuation(is_from_young,
1.162 + is_to_young,
1.163 queue_num(),
1.164 obj);
1.165 }
1.166
1.167 - size_t* surv_young_words = surviving_young_words();
1.168 + size_t* const surv_young_words = surviving_young_words();
1.169 surv_young_words[young_index] += word_sz;
1.170
1.171 if (obj->is_objArray() && arrayOop(obj)->length() >= ParGCArrayScanChunk) {
1.172 @@ -232,14 +287,13 @@
1.173 oop* old_p = set_partial_array_mask(old);
1.174 push_on_queue(old_p);
1.175 } else {
1.176 - // No point in using the slower heap_region_containing() method,
1.177 - // given that we know obj is in the heap.
1.178 - _scanner.set_region(_g1h->heap_region_containing_raw(obj));
1.179 + HeapRegion* const to_region = _g1h->heap_region_containing_raw(obj_ptr);
1.180 + _scanner.set_region(to_region);
1.181 obj->oop_iterate_backwards(&_scanner);
1.182 }
1.183 + return obj;
1.184 } else {
1.185 - _g1_par_allocator->undo_allocation(alloc_purpose, obj_ptr, word_sz, context);
1.186 - obj = forward_ptr;
1.187 + _g1_par_allocator->undo_allocation(dest_state, obj_ptr, word_sz, context);
1.188 + return forward_ptr;
1.189 }
1.190 - return obj;
1.191 }
