/*

 * Copyright (c) 2017, 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.

 *

 */

#include "precompiled.hpp"

#include "gc/g1/g1CollectedHeap.hpp"

#include "gc/g1/g1FullCollector.hpp"

#include "gc/g1/g1FullGCMarker.hpp"

#include "gc/g1/g1FullGCOopClosures.inline.hpp"

#include "gc/g1/g1FullGCReferenceProcessorExecutor.hpp"

#include "gc/shared/gcTraceTime.inline.hpp"

#include "gc/shared/referenceProcessor.hpp"

G1FullGCReferenceProcessingExecutor::G1FullGCReferenceProcessingExecutor(G1FullCollector* collector) :

    _collector(collector),

    _reference_processor(collector->reference_processor()),

    _old_mt_degree(_reference_processor->num_q()) {

  if (_reference_processor->processing_is_mt()) {

    _reference_processor->set_active_mt_degree(_collector->workers());

  }

}

G1FullGCReferenceProcessingExecutor::~G1FullGCReferenceProcessingExecutor() {

  if (_reference_processor->processing_is_mt()) {

    _reference_processor->set_active_mt_degree(_old_mt_degree);

  }

}

G1FullGCReferenceProcessingExecutor::G1RefProcTaskProxy::G1RefProcTaskProxy(ProcessTask& proc_task,

                                                                      G1FullCollector* collector) :

     AbstractGangTask("G1 reference processing task"),

     _proc_task(proc_task),

     _collector(collector),

     _terminator(_collector->workers(), _collector->oop_queue_set()) { }

void G1FullGCReferenceProcessingExecutor::G1RefProcTaskProxy::work(uint worker_id) {

  G1FullGCMarker* marker = _collector->marker(worker_id);

  G1IsAliveClosure is_alive(_collector->mark_bitmap());

  G1FullKeepAliveClosure keep_alive(marker);

  _proc_task.work(worker_id,

                  is_alive,

                  keep_alive,

                  *marker->stack_closure());

}

G1FullGCReferenceProcessingExecutor::G1RefEnqueueTaskProxy::G1RefEnqueueTaskProxy(EnqueueTask& enq_task) :

  AbstractGangTask("G1 reference enqueue task"),

  _enq_task(enq_task) { }

void G1FullGCReferenceProcessingExecutor::G1RefEnqueueTaskProxy::work(uint worker_id) {

  _enq_task.work(worker_id);

}

void G1FullGCReferenceProcessingExecutor::run_task(AbstractGangTask* task) {

  G1CollectedHeap::heap()->workers()->run_task(task, _collector->workers());

}

void G1FullGCReferenceProcessingExecutor::execute(ProcessTask& proc_task) {

  G1RefProcTaskProxy proc_task_proxy(proc_task, _collector);

  run_task(&proc_task_proxy);

}

// Driver routine for parallel reference processing.

void G1FullGCReferenceProcessingExecutor::execute(EnqueueTask& enq_task) {

  G1RefEnqueueTaskProxy enq_task_proxy(enq_task);

  run_task(&enq_task_proxy);

}

void G1FullGCReferenceProcessingExecutor::execute(STWGCTimer* timer, G1FullGCTracer* tracer) {

  GCTraceTime(Debug, gc, phases) debug("Phase 1: Reference Processing", timer);

  // Process reference objects found during marking.

  G1FullGCMarker* marker = _collector->marker(0);

  G1IsAliveClosure is_alive(_collector->mark_bitmap());

  G1FullKeepAliveClosure keep_alive(marker);

  ReferenceProcessorPhaseTimes pt(timer, _reference_processor->num_q());

  AbstractRefProcTaskExecutor* executor = _reference_processor->processing_is_mt() ? this : NULL;

  // Process discovered references, use this executor if multi-threaded

  // processing is enabled.

  const ReferenceProcessorStats& stats =

      _reference_processor->process_discovered_references(&is_alive,

                                                          &keep_alive,

                                                          marker->stack_closure(),

                                                          executor,

                                                          &pt);

  tracer->report_gc_reference_stats(stats);

  pt.print_all_references();

  assert(marker->oop_stack()->is_empty(), "Should be no oops on the stack");

  // Now enqueue the references.

  _reference_processor->enqueue_discovered_references(executor, &pt);

  pt.print_enqueue_phase();

}