/*

 * Copyright (c) 2001, 2019, 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/g1BarrierSet.inline.hpp"

#include "gc/g1/g1BarrierSetAssembler.hpp"

#include "gc/g1/g1CardTable.inline.hpp"

#include "gc/g1/g1CollectedHeap.inline.hpp"

#include "gc/g1/g1SATBMarkQueueSet.hpp"

#include "gc/g1/g1ThreadLocalData.hpp"

#include "gc/g1/heapRegion.hpp"

#include "gc/shared/satbMarkQueue.hpp"

#include "logging/log.hpp"

#include "oops/access.inline.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/interfaceSupport.inline.hpp"

#include "runtime/mutexLocker.hpp"

#include "runtime/thread.inline.hpp"

#include "utilities/macros.hpp"

#ifdef COMPILER1

#include "gc/g1/c1/g1BarrierSetC1.hpp"

#endif

#ifdef COMPILER2

#include "gc/g1/c2/g1BarrierSetC2.hpp"

#endif

class G1BarrierSetC1;

class G1BarrierSetC2;

G1BarrierSet::G1BarrierSet(G1CardTable* card_table) :

  CardTableBarrierSet(make_barrier_set_assembler<G1BarrierSetAssembler>(),

                      make_barrier_set_c1<G1BarrierSetC1>(),

                      make_barrier_set_c2<G1BarrierSetC2>(),

                      card_table,

                      BarrierSet::FakeRtti(BarrierSet::G1BarrierSet)),

  _satb_mark_queue_buffer_allocator("SATB Buffer Allocator", G1SATBBufferSize),

  _dirty_card_queue_buffer_allocator("DC Buffer Allocator", G1UpdateBufferSize),

  _satb_mark_queue_set(),

  _dirty_card_queue_set()

{}

void G1BarrierSet::enqueue(oop pre_val) {

  // Nulls should have been already filtered.

  assert(oopDesc::is_oop(pre_val, true), "Error");

  G1ThreadLocalData::satb_mark_queue(Thread::current()).enqueue(pre_val);

}

template <class T> void

G1BarrierSet::write_ref_array_pre_work(T* dst, size_t count) {

  if (!_satb_mark_queue_set.is_active()) return;

  T* elem_ptr = dst;

  for (size_t i = 0; i < count; i++, elem_ptr++) {

    T heap_oop = RawAccess<>::oop_load(elem_ptr);

    if (!CompressedOops::is_null(heap_oop)) {

      enqueue(CompressedOops::decode_not_null(heap_oop));

    }

  }

}

void G1BarrierSet::write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized) {

  if (!dest_uninitialized) {

    write_ref_array_pre_work(dst, count);

  }

}

void G1BarrierSet::write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized) {

  if (!dest_uninitialized) {

    write_ref_array_pre_work(dst, count);

  }

}

  // In the slow path, we know a card is not young

  assert(*byte != G1CardTable::g1_young_card_val(), "slow path invoked without filtering");

  OrderAccess::storeload();

  if (*byte != G1CardTable::dirty_card_val()) {

    *byte = G1CardTable::dirty_card_val();

    Thread* thr = Thread::current();

    G1ThreadLocalData::dirty_card_queue(thr).enqueue(byte);

  }

}

void G1BarrierSet::invalidate(MemRegion mr) {

  if (mr.is_empty()) {

    return;

  }

  // skip initial young cards

  for (; byte <= last_byte && *byte == G1CardTable::g1_young_card_val(); byte++);

  if (byte <= last_byte) {

    OrderAccess::storeload();

    // Enqueue if necessary.

    Thread* thr = Thread::current();

    G1DirtyCardQueue& queue = G1ThreadLocalData::dirty_card_queue(thr);

    for (; byte <= last_byte; byte++) {

      if ((bv != G1CardTable::g1_young_card_val()) &&

          (bv != G1CardTable::dirty_card_val())) {

        *byte = G1CardTable::dirty_card_val();

        queue.enqueue(byte);

      }

    }

  }

}

void G1BarrierSet::on_thread_create(Thread* thread) {

  // Create thread local data

  G1ThreadLocalData::create(thread);

}

void G1BarrierSet::on_thread_destroy(Thread* thread) {

  // Destroy thread local data

  G1ThreadLocalData::destroy(thread);

}

void G1BarrierSet::on_thread_attach(Thread* thread) {

  assert(!G1ThreadLocalData::satb_mark_queue(thread).is_active(), "SATB queue should not be active");

  assert(G1ThreadLocalData::satb_mark_queue(thread).is_empty(), "SATB queue should be empty");

  assert(G1ThreadLocalData::dirty_card_queue(thread).is_active(), "Dirty card queue should be active");

  // Can't assert that the DCQ is empty.  There is early execution on

  // the main thread, before it gets added to the threads list, which

  // is where this is called.  That execution may enqueue dirty cards.

  // If we are creating the thread during a marking cycle, we should

  // set the active field of the SATB queue to true.  That involves

  // copying the global is_active value to this thread's queue, which

  // is done without any direct synchronization here.

  //

  // The activation and deactivation of the SATB queues occurs at the

  // beginning / end of a marking cycle, and is done during

  // safepoints.  This function is called just before a thread is

  // added to its corresponding threads list (for Java or non-Java

  // threads, respectively).

  //

  // For Java threads, that's done while holding the Threads_lock,

  // which ensures we're not at a safepoint, so reading the global

  // is_active state is synchronized against update.

  assert(!thread->is_Java_thread() || !SafepointSynchronize::is_at_safepoint(),

         "Should not be at a safepoint");

  // For non-Java threads, thread creation (and list addition) may,

  // and indeed usually does, occur during a safepoint.  But such

  // creation isn't concurrent with updating the global SATB active

  // state.

  bool is_satb_active = _satb_mark_queue_set.is_active();

  G1ThreadLocalData::satb_mark_queue(thread).set_active(is_satb_active);

}

void G1BarrierSet::on_thread_detach(Thread* thread) {

  // Flush any deferred card marks.

  CardTableBarrierSet::on_thread_detach(thread);

  G1ThreadLocalData::satb_mark_queue(thread).flush();

  G1ThreadLocalData::dirty_card_queue(thread).flush();

}

BufferNode::Allocator& G1BarrierSet::satb_mark_queue_buffer_allocator() {

  return _satb_mark_queue_buffer_allocator;

}

BufferNode::Allocator& G1BarrierSet::dirty_card_queue_buffer_allocator() {

  return _dirty_card_queue_buffer_allocator;

}