1 /*
  2  * Copyright (c) 2013, 2022, Red Hat, Inc. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #include "precompiled.hpp"
 26 #include "gc/shared/barrierSetNMethod.hpp"
 27 #include "gc/shenandoah/shenandoahBarrierSetClone.inline.hpp"
 28 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
 29 #include "gc/shenandoah/shenandoahBarrierSetNMethod.hpp"
 30 #include "gc/shenandoah/shenandoahBarrierSetStackChunk.hpp"
 31 #include "gc/shenandoah/shenandoahClosures.inline.hpp"
 32 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
 33 #include "gc/shenandoah/shenandoahStackWatermark.hpp"
 34 #ifdef COMPILER1
 35 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
 36 #endif
 37 #ifdef COMPILER2
 38 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
 39 #endif
 40 
 41 class ShenandoahBarrierSetC1;
 42 class ShenandoahBarrierSetC2;
 43 
 44 ShenandoahBarrierSet::ShenandoahBarrierSet(ShenandoahHeap* heap) :
 45   BarrierSet(make_barrier_set_assembler<ShenandoahBarrierSetAssembler>(),
 46              make_barrier_set_c1<ShenandoahBarrierSetC1>(),
 47              make_barrier_set_c2<ShenandoahBarrierSetC2>(),
 48              new ShenandoahBarrierSetNMethod(heap),
 49              new ShenandoahBarrierSetStackChunk(),
 50              BarrierSet::FakeRtti(BarrierSet::ShenandoahBarrierSet)),
 51   _heap(heap),
 52   _satb_mark_queue_buffer_allocator("SATB Buffer Allocator", ShenandoahSATBBufferSize),
 53   _satb_mark_queue_set(&_satb_mark_queue_buffer_allocator)
 54 {
 55 }
 56 
 57 ShenandoahBarrierSetAssembler* ShenandoahBarrierSet::assembler() {
 58   BarrierSetAssembler* const bsa = BarrierSet::barrier_set()->barrier_set_assembler();
 59   return reinterpret_cast<ShenandoahBarrierSetAssembler*>(bsa);
 60 }
 61 
 62 void ShenandoahBarrierSet::print_on(outputStream* st) const {
 63   st->print("ShenandoahBarrierSet");
 64 }
 65 
 66 bool ShenandoahBarrierSet::need_load_reference_barrier(DecoratorSet decorators, BasicType type) {
 67   if (!ShenandoahLoadRefBarrier) return false;
 68   // Only needed for references
 69   return is_reference_type(type);
 70 }
 71 
 72 bool ShenandoahBarrierSet::need_keep_alive_barrier(DecoratorSet decorators, BasicType type) {
 73   if (!ShenandoahSATBBarrier) return false;
 74   // Only needed for references
 75   if (!is_reference_type(type)) return false;
 76 
 77   bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
 78   bool unknown = (decorators & ON_UNKNOWN_OOP_REF) != 0;
 79   bool on_weak_ref = (decorators & (ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF)) != 0;
 80   return (on_weak_ref || unknown) && keep_alive;
 81 }
 82 
 83 void ShenandoahBarrierSet::on_thread_create(Thread* thread) {
 84   // Create thread local data
 85   ShenandoahThreadLocalData::create(thread);
 86 }
 87 
 88 void ShenandoahBarrierSet::on_thread_destroy(Thread* thread) {
 89   // Destroy thread local data
 90   ShenandoahThreadLocalData::destroy(thread);
 91 }
 92 
 93 void ShenandoahBarrierSet::on_thread_attach(Thread *thread) {
 94   assert(!thread->is_Java_thread() || !SafepointSynchronize::is_at_safepoint(),
 95          "We should not be at a safepoint");
 96   SATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
 97   assert(!queue.is_active(), "SATB queue should not be active");
 98   assert(queue.buffer() == nullptr, "SATB queue should not have a buffer");
 99   assert(queue.index() == 0, "SATB queue index should be zero");
100   queue.set_active(_satb_mark_queue_set.is_active());
101   if (thread->is_Java_thread()) {
102     ShenandoahThreadLocalData::set_gc_state(thread, _heap->gc_state());
103     ShenandoahThreadLocalData::initialize_gclab(thread);
104 
105     BarrierSetNMethod* bs_nm = barrier_set_nmethod();
106     if (bs_nm != nullptr) {
107       thread->set_nmethod_disarmed_guard_value(bs_nm->disarmed_guard_value());
108     }
109 
110     if (ShenandoahStackWatermarkBarrier) {
111       JavaThread* const jt = JavaThread::cast(thread);
112       StackWatermark* const watermark = new ShenandoahStackWatermark(jt);
113       StackWatermarkSet::add_watermark(jt, watermark);
114     }
115   }
116 }
117 
118 void ShenandoahBarrierSet::on_thread_detach(Thread *thread) {
119   SATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
120   _satb_mark_queue_set.flush_queue(queue);
121   if (thread->is_Java_thread()) {
122     PLAB* gclab = ShenandoahThreadLocalData::gclab(thread);
123     if (gclab != nullptr) {
124       gclab->retire();
125     }
126 
127     // SATB protocol requires to keep alive reachable oops from roots at the beginning of GC
128     if (ShenandoahStackWatermarkBarrier) {
129       if (_heap->is_concurrent_mark_in_progress()) {
130         ShenandoahKeepAliveClosure oops;
131         StackWatermarkSet::finish_processing(JavaThread::cast(thread), &oops, StackWatermarkKind::gc);
132       } else if (_heap->is_concurrent_weak_root_in_progress() && _heap->is_evacuation_in_progress()) {
133         ShenandoahContextEvacuateUpdateRootsClosure oops;
134         StackWatermarkSet::finish_processing(JavaThread::cast(thread), &oops, StackWatermarkKind::gc);
135       }
136     }
137   }
138 }
139 
140 void ShenandoahBarrierSet::clone_barrier_runtime(oop src) {
141   if (_heap->has_forwarded_objects() || (ShenandoahIUBarrier && _heap->is_concurrent_mark_in_progress())) {
142     clone_barrier(src);
143   }
144 }