src/hotspot/share/jfr/utilities/jfrEpochQueue.inline.hpp

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#ifndef SHARE_JFR_UTILITIES_JFREPOCHQUEUE_INLINE_HPP
#define SHARE_JFR_UTILITIES_JFREPOCHQUEUE_INLINE_HPP

#include "jfr/utilities/jfrEpochQueue.hpp"
#include "jfr/recorder/storage/jfrEpochStorage.inline.hpp"
#include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
#include "runtime/javaThread.hpp"

template <template <typename> class ElementPolicy>
JfrEpochQueue<ElementPolicy>::JfrEpochQueue() : _storage(nullptr) {}

template <template <typename> class ElementPolicy>
JfrEpochQueue<ElementPolicy>::~JfrEpochQueue() {
  delete _storage;
}

template <template <typename> class ElementPolicy>
bool JfrEpochQueue<ElementPolicy>::initialize(size_t min_buffer_size, size_t free_list_cache_count_limit, size_t cache_prealloc_count) {
  assert(_storage == nullptr, "invariant");
  _storage = new JfrEpochStorage();
  return _storage != nullptr && _storage->initialize(min_buffer_size, free_list_cache_count_limit, cache_prealloc_count);
}

template <template <typename> class ElementPolicy>
inline typename JfrEpochQueue<ElementPolicy>::BufferPtr
JfrEpochQueue<ElementPolicy>::renew(size_t size, Thread* thread) {
  assert(thread != nullptr, "invariant");
  BufferPtr buffer = this->thread_local_storage(thread);
  if (buffer != nullptr) {
    _storage->release(buffer);
  }
  buffer = _storage->acquire(size, thread);
  assert(buffer != nullptr, "invariant");
  assert(buffer->free_size() >= size, "invariant");
  this->set_thread_local_storage(buffer, thread);
  assert(this->thread_local_storage(thread) == buffer, "invariant");
  return buffer;
}

template <template <typename> class ElementPolicy>
inline typename JfrEpochQueue<ElementPolicy>::BufferPtr
JfrEpochQueue<ElementPolicy>::storage_for_element(JfrEpochQueue<ElementPolicy>::TypePtr t, size_t element_size) {
  assert(this->element_size(t) == element_size, "invariant");
  Thread* const thread = Thread::current();
  BufferPtr buffer = this->thread_local_storage(thread);
  if (buffer == nullptr) {
    buffer = _storage->acquire(element_size, thread);
    this->set_thread_local_storage(buffer, thread);
  } else if (buffer->free_size() < element_size) {
    _storage->release(buffer);
    buffer = _storage->acquire(element_size, thread);
    this->set_thread_local_storage(buffer, thread);
  }
  assert(buffer->free_size() >= element_size, "invariant");
  assert(this->thread_local_storage(thread) == buffer, "invariant");
  return buffer;
}

template <template <typename> class ElementPolicy>
void JfrEpochQueue<ElementPolicy>::enqueue(JfrEpochQueue<ElementPolicy>::TypePtr t) {
  assert(t != nullptr, "invariant");
  size_t element_size = this->element_size(t);
  BufferPtr buffer = storage_for_element(t, element_size);
  assert(buffer != nullptr, "invariant");
  this->store_element(t, buffer);
  buffer->set_pos(element_size);
}

template <template <typename> class ElementPolicy>
template <typename Callback>
JfrEpochQueue<ElementPolicy>::ElementDispatch<Callback>::ElementDispatch(Callback& callback, JfrEpochQueue<ElementPolicy>& queue) :
  _callback(callback), _queue(queue) {}

template <template <typename> class ElementPolicy>
template <typename Callback>
size_t JfrEpochQueue<ElementPolicy>::ElementDispatch<Callback>::operator()(const u1* element, bool previous_epoch) {
  assert(element != nullptr, "invariant");
  return _queue(element, _callback, previous_epoch);
}

template <template <typename> class ElementPolicy>
template <typename Callback>
void JfrEpochQueue<ElementPolicy>::iterate(Callback& callback, bool previous_epoch) {
  typedef ElementDispatch<Callback> ElementDispatcher;
  typedef EpochDispatchOp<ElementDispatcher> QueueDispatcher;
  ElementDispatcher element_dispatcher(callback, *this);
  QueueDispatcher dispatch(element_dispatcher, previous_epoch);
  _storage->iterate(dispatch, previous_epoch);
  DEBUG_ONLY(_storage->verify_previous_empty();)
}

#endif // SHARE_JFR_UTILITIES_JFREPOCHQUEUE_INLINE_HPP