src/hotspot/share/gc/g1/g1ParScanThreadState.inline.hpp

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#ifndef SHARE_GC_G1_G1PARSCANTHREADSTATE_INLINE_HPP
#define SHARE_GC_G1_G1PARSCANTHREADSTATE_INLINE_HPP

#include "gc/g1/g1ParScanThreadState.hpp"

#include "gc/g1/g1CardTable.hpp"
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1OopStarChunkedList.inline.hpp"
#include "gc/g1/g1RemSet.hpp"
#include "oops/access.inline.hpp"
#include "oops/oop.inline.hpp"

inline void G1ParScanThreadState::push_on_queue(ScannerTask task) {
  verify_task(task);
  _task_queue->push(task);
}

bool G1ParScanThreadState::needs_partial_trimming() const {
  return !_task_queue->overflow_empty() ||
         (_task_queue->size() > _stack_trim_upper_threshold);
}

void G1ParScanThreadState::trim_queue_partially() {
  if (!needs_partial_trimming()) {
    return;
  }

  const Ticks start = Ticks::now();
  trim_queue_to_threshold(_stack_trim_lower_threshold);
  assert(_task_queue->overflow_empty(), "invariant");
  assert(_task_queue->size() <= _stack_trim_lower_threshold, "invariant");
  _trim_ticks += Ticks::now() - start;
}

void G1ParScanThreadState::trim_queue() {
  trim_queue_to_threshold(0);
  assert(_task_queue->overflow_empty(), "invariant");
  assert(_task_queue->taskqueue_empty(), "invariant");
}

inline Tickspan G1ParScanThreadState::trim_ticks() const {
  return _trim_ticks;
}

inline void G1ParScanThreadState::reset_trim_ticks() {
  _trim_ticks = Tickspan();
}

template <typename T>
inline void G1ParScanThreadState::remember_root_into_optional_region(T* p) {
  oop o = RawAccess<IS_NOT_NULL>::oop_load(p);
  uint index = _g1h->heap_region_containing(o)->index_in_opt_cset();
  assert(index < _max_num_optional_regions,
         "Trying to access optional region idx %u beyond %zu", index, _max_num_optional_regions);
  _oops_into_optional_regions[index].push_root(p);
}

template <typename T>
inline void G1ParScanThreadState::remember_reference_into_optional_region(T* p) {
  oop o = RawAccess<IS_NOT_NULL>::oop_load(p);
  uint index = _g1h->heap_region_containing(o)->index_in_opt_cset();
  assert(index < _max_num_optional_regions,
         "Trying to access optional region idx %u beyond %zu", index, _max_num_optional_regions);
  _oops_into_optional_regions[index].push_oop(p);
  verify_task(p);
}

G1OopStarChunkedList* G1ParScanThreadState::oops_into_optional_region(const G1HeapRegion* hr) {
  assert(hr->index_in_opt_cset() < _max_num_optional_regions,
         "Trying to access optional region idx %u beyond %zu " HR_FORMAT,
         hr->index_in_opt_cset(), _max_num_optional_regions, HR_FORMAT_PARAMS(hr));
  return &_oops_into_optional_regions[hr->index_in_opt_cset()];
}

template <class T> bool G1ParScanThreadState::enqueue_if_new(T* p) {
  size_t card_index = ct()->index_for(p);
  // If the card hasn't been added to the buffer, do it.
  if (_last_enqueued_card != card_index) {
    _rdc_local_qset.enqueue(ct()->byte_for_index(card_index));
    _last_enqueued_card = card_index;
    return true;
  } else {
    return false;
  }
}

template <class T> void G1ParScanThreadState::enqueue_card_into_evac_fail_region(T* p, oop obj) {
  assert(!G1HeapRegion::is_in_same_region(p, obj), "Should have filtered out cross-region references already.");
  assert(!_g1h->heap_region_containing(p)->is_survivor(), "Should have filtered out from-newly allocated survivor references already.");
  assert(_g1h->heap_region_containing(obj)->in_collection_set(), "Only for enqeueing reference into collection set region");

  if (enqueue_if_new(p)) {
    _evac_failure_enqueued_cards++;
  }
}

template <class T> void G1ParScanThreadState::write_ref_field_post(T* p, oop obj) {
  assert(obj != nullptr, "Must be");
  if (G1HeapRegion::is_in_same_region(p, obj)) {
    return;
  }
  G1HeapRegionAttr from_attr = _g1h->region_attr(p);
  // If this is a reference from (current) survivor regions, we do not need
  // to track references from it.
  if (from_attr.is_new_survivor()) {
    return;
  }
  G1HeapRegionAttr dest_attr = _g1h->region_attr(obj);
  // References to the current collection set are references to objects that failed
  // evacuation. Proactively collect remembered sets (cards) for them as likely they
  // are sparsely populated (and have few references). We will decide later to keep
  // or drop the region.
  if (dest_attr.is_in_cset()) {
    assert(obj->is_forwarded(), "evac-failed but not forwarded: " PTR_FORMAT, p2i(obj));
    assert(obj->forwardee() == obj, "evac-failed but not self-forwarded: " PTR_FORMAT, p2i(obj));
    enqueue_card_into_evac_fail_region(p, obj);
    return;
  }
  enqueue_card_if_tracked(dest_attr, p, obj);
}

template <class T> void G1ParScanThreadState::enqueue_card_if_tracked(G1HeapRegionAttr region_attr, T* p, oop o) {
  assert(!G1HeapRegion::is_in_same_region(p, o), "Should have filtered out cross-region references already.");
  assert(!_g1h->heap_region_containing(p)->is_survivor(), "Should have filtered out from-newly allocated survivor references already.");
  // We relabel all regions that failed evacuation as old gen without remembered,
  // and so pre-filter them out in the caller.
  assert(!_g1h->heap_region_containing(o)->in_collection_set(), "Should not try to enqueue reference into collection set region");

#ifdef ASSERT
  G1HeapRegion* const hr_obj = _g1h->heap_region_containing(o);
  assert(region_attr.remset_is_tracked() == hr_obj->rem_set()->is_tracked(),
         "State flag indicating remset tracking disagrees (%s) with actual remembered set (%s) for region %u",
         BOOL_TO_STR(region_attr.remset_is_tracked()),
         BOOL_TO_STR(hr_obj->rem_set()->is_tracked()),
         hr_obj->hrm_index());
#endif
  if (!region_attr.remset_is_tracked()) {
    return;
  }
  enqueue_if_new(p);
}

#endif // SHARE_GC_G1_G1PARSCANTHREADSTATE_INLINE_HPP