src/hotspot/share/gc/shared/partialArraySplitter.inline.hpp

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#ifndef SHARE_GC_SHARED_PARTIALARRAYSPLITTER_INLINE_HPP
#define SHARE_GC_SHARED_PARTIALARRAYSPLITTER_INLINE_HPP

#include "gc/shared/partialArraySplitter.hpp"

#include "gc/shared/partialArrayTaskStats.hpp"
#include "gc/shared/partialArrayTaskStepper.inline.hpp"
#include "gc/shared/taskqueue.inline.hpp"
#include "oops/oop.hpp"
#include "utilities/debug.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/macros.hpp"

template<typename Queue>
size_t PartialArraySplitter::start(Queue* queue,
                                   objArrayOop source,
                                   objArrayOop destination,
                                   size_t length) {
  PartialArrayTaskStepper::Step step = _stepper.start(length);
  // Push initial partial scan tasks.
  if (step._ncreate > 0) {
    TASKQUEUE_STATS_ONLY(_stats.inc_split(););
    TASKQUEUE_STATS_ONLY(_stats.inc_pushed(step._ncreate);)
    PartialArrayState* state =
      _allocator.allocate(source, destination, step._index, length, step._ncreate);
    for (uint i = 0; i < step._ncreate; ++i) {
      queue->push(ScannerTask(state));
    }
  } else {
    assert(step._index == length, "invariant");
  }
  return step._index;
}

template<typename Queue>
PartialArraySplitter::Claim
PartialArraySplitter::claim(PartialArrayState* state, Queue* queue, bool stolen) {
#if TASKQUEUE_STATS
  if (stolen) _stats.inc_stolen();
  _stats.inc_processed();
#endif // TASKQUEUE_STATS

  // Claim a chunk and get number of additional tasks to enqueue.
  PartialArrayTaskStepper::Step step = _stepper.next(state);
  // Push additional tasks.
  if (step._ncreate > 0) {
    TASKQUEUE_STATS_ONLY(_stats.inc_pushed(step._ncreate);)
    // Adjust reference count for tasks being added to the queue.
    state->add_references(step._ncreate);
    for (uint i = 0; i < step._ncreate; ++i) {
      queue->push(ScannerTask(state));
    }
  }
  // Release state, decrementing refcount, now that we're done with it.
  _allocator.release(state);
  return Claim{step._index, step._index + _stepper.chunk_size()};
}

#endif // SHARE_GC_SHARED_PARTIALARRAYSPLITTER_INLINE_HPP