src/hotspot/share/gc/g1/g1HeapRegionRemSet.cpp

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#include "gc/g1/g1BlockOffsetTable.inline.hpp"
#include "gc/g1/g1CardSetContainers.inline.hpp"
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1ConcurrentRefine.hpp"
#include "gc/g1/g1HeapRegionManager.inline.hpp"
#include "gc/g1/g1HeapRegionRemSet.inline.hpp"
#include "memory/allocation.hpp"
#include "memory/padded.inline.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/atomic.hpp"
#include "runtime/globals_extension.hpp"
#include "runtime/java.hpp"
#include "runtime/mutexLocker.hpp"
#include "utilities/bitMap.inline.hpp"
#include "utilities/debug.hpp"
#include "utilities/formatBuffer.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/powerOfTwo.hpp"

HeapWord* G1HeapRegionRemSet::_heap_base_address = nullptr;

const char* G1HeapRegionRemSet::_state_strings[] =  {"Untracked", "Updating", "Complete"};
const char* G1HeapRegionRemSet::_short_state_strings[] =  {"UNTRA", "UPDAT", "CMPLT"};

void G1HeapRegionRemSet::initialize(MemRegion reserved) {
  G1CardSet::initialize(reserved);
  _heap_base_address = reserved.start();
}

void G1HeapRegionRemSet::uninstall_cset_group() {
  _cset_group = nullptr;
}

G1HeapRegionRemSet::G1HeapRegionRemSet(G1HeapRegion* hr) :
  _code_roots(),
  _cset_group(nullptr),
  _hr(hr),
  _state(Untracked) { }

G1HeapRegionRemSet::~G1HeapRegionRemSet() {
  assert(!is_added_to_cset_group(), "Still assigned to a CSet group");
}

void G1HeapRegionRemSet::clear_fcc() {
  G1FromCardCache::clear(_hr->hrm_index());
}

void G1HeapRegionRemSet::clear(bool only_cardset, bool keep_tracked) {
  if (!only_cardset) {
    _code_roots.clear();
  }
  clear_fcc();

  if (is_added_to_cset_group()) {
    card_set()->clear();
    assert(card_set()->occupied() == 0, "Should be clear.");
  }

  if (!keep_tracked) {
    set_state_untracked();
  } else {
    assert(is_tracked(), "must be");
  }
}

void G1HeapRegionRemSet::reset_table_scanner() {
  _code_roots.reset_table_scanner();
  if (is_added_to_cset_group()) {
    card_set()->reset_table_scanner();
  }
}

G1MonotonicArenaMemoryStats G1HeapRegionRemSet::card_set_memory_stats() const {
  assert(is_added_to_cset_group(), "pre-condition");
  return cset_group()->card_set_memory_stats();
}

void G1HeapRegionRemSet::print_static_mem_size(outputStream* out) {
  out->print_cr("  Static structures = %zu", G1HeapRegionRemSet::static_mem_size());
}

// Code roots support
//
// The code root set is protected by two separate locking schemes
// When at safepoint the per-hrrs lock must be held during modifications
// except when doing a full gc.
// When not at safepoint the CodeCache_lock must be held during modifications.

void G1HeapRegionRemSet::add_code_root(nmethod* nm) {
  assert(nm != nullptr, "sanity");
  _code_roots.add(nm);
}

void G1HeapRegionRemSet::remove_code_root(nmethod* nm) {
  assert(nm != nullptr, "sanity");

  _code_roots.remove(nm);

  // Check that there were no duplicates
  guarantee(!_code_roots.contains(nm), "duplicate entry found");
}

void G1HeapRegionRemSet::bulk_remove_code_roots() {
  _code_roots.bulk_remove();
}

void G1HeapRegionRemSet::code_roots_do(NMethodClosure* blk) const {
  _code_roots.nmethods_do(blk);
}

void G1HeapRegionRemSet::clean_code_roots(G1HeapRegion* hr) {
  _code_roots.clean(hr);
}

size_t G1HeapRegionRemSet::code_roots_mem_size() {
  return _code_roots.mem_size();
}