Quelle  g1BarrierSet.cpp   Sprache: C

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
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 * accompanied this code).
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#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/javaThread.hpp"
#include "runtime/orderAccess.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(&_satb_mark_queue_buffer_allocator),
  _dirty_card_queue_set(&_dirty_card_queue_buffer_allocator)
{}

template <class T> void
G1BarrierSet::write_ref_array_pre_work(T* dst, size_t count) {
  G1SATBMarkQueueSet& queue_set = G1BarrierSet::satb_mark_queue_set();
  if (!queue_set.is_active()) return;

  SATBMarkQueue& queue = G1ThreadLocalData::satb_mark_queue(Thread::current());

  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)) {
      queue_set.enqueue_known_active(queue, 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);
  }
}

void G1BarrierSet::write_ref_field_post_slow(volatile CardValue* byte) {
  // 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();
    G1DirtyCardQueue& queue = G1ThreadLocalData::dirty_card_queue(thr);
    G1BarrierSet::dirty_card_queue_set().enqueue(queue, byte);
  }
}

void G1BarrierSet::invalidate(MemRegion mr) {
  if (mr.is_empty()) {
    return;
  }
  volatile CardValue* byte = _card_table->byte_for(mr.start());
  CardValue* last_byte = _card_table->byte_for(mr.last());
  // 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();
    G1DirtyCardQueueSet& qset = G1BarrierSet::dirty_card_queue_set();
    G1DirtyCardQueue& queue = G1ThreadLocalData::dirty_card_queue(thr);
    for (; byte <= last_byte; byte++) {
      CardValue bv = *byte;
      if ((bv != G1CardTable::g1_young_card_val()) &&
          (bv != G1CardTable::dirty_card_val())) {
        *byte = G1CardTable::dirty_card_val();
        qset.enqueue(queue, 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) {
  BarrierSet::on_thread_attach(thread);
  SATBMarkQueue& queue = G1ThreadLocalData::satb_mark_queue(thread);
  assert(!queue.is_active(), "SATB queue should not be active");
  assert(queue.buffer() == nullptr, "SATB queue should not have a buffer");
  assert(queue.index() == 0, "SATB queue index should be zero");
  // 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.
  queue.set_active(_satb_mark_queue_set.is_active());
}

void G1BarrierSet::on_thread_detach(Thread* thread) {
  // Flush any deferred card marks.
  CardTableBarrierSet::on_thread_detach(thread);
  {
    SATBMarkQueue& queue = G1ThreadLocalData::satb_mark_queue(thread);
    G1BarrierSet::satb_mark_queue_set().flush_queue(queue);
  }
  {
    G1DirtyCardQueue& queue = G1ThreadLocalData::dirty_card_queue(thread);
    G1DirtyCardQueueSet& qset = G1BarrierSet::dirty_card_queue_set();
    qset.flush_queue(queue);
    qset.record_detached_refinement_stats(queue.refinement_stats());
  }
}