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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_VM_GC_G1_MEMORY_NODE_MANAGER_HPP
#define SHARE_VM_GC_G1_MEMORY_NODE_MANAGER_HPP

#include "memory/allocation.hpp"
#include "runtime/os.hpp"

// Helper class to manage memory nodes.
// G1MemoryMultiNodeManager will be created if UseNUMA is enabled and active
// NUMA nodes are more than one. Otherwise, G1MemoryNodeManager will be created.
class G1MemoryNodeManager : public CHeapObj<mtGC> {
  static G1MemoryNodeManager* _inst;

protected:
  G1MemoryNodeManager() { }

public:
  static const uint UnknownNodeIndex = UINT_MAX;
  static const uint AnyNodeIndex = UnknownNodeIndex - 1;

  static G1MemoryNodeManager* mgr() { return _inst; }

  static G1MemoryNodeManager* create();

  virtual ~G1MemoryNodeManager() { }

  // Set heap region size and page size after those values are determined
  // at G1CollectedHeap::initialize().
  virtual void set_region_info(size_t region_size, size_t page_size) { }

  // Print current active memory node count.
  virtual uint num_active_nodes() const { return 1; }

  virtual bool has_multi_nodes() const { return false; }

  // Returns memory node ids
  virtual const int* node_ids() const;

  // Returns node index of current calling thread.
  virtual uint index_of_current_thread() const { return 0; }

  // Returns the preferred index for the given HeapRegion index.
  // This assumes that HeapRegions are evenly spit, so we can decide preferred index
  // with the given HeapRegion index.
  // Result is less than num_active_nodes().
  virtual uint preferred_node_index_for_index(uint region_index) const { return 0; }

  // Retrieve node index of the given address.
  // Result is less than num_active_nodes() or is UnknownNodeIndex.
  // Precondition: address is in reserved range for heap.
  virtual uint index_of_address(HeapWord* address) const { return 0; }

  // Request the given memory area to be located at the given node index.
  virtual void request_memory_on_node(char* aligned_address, size_t size_in_bytes, uint node_index) { }

  // Returns maximum search depth which is used to limit heap region search iterations.
  // The number of active nodes, page size and heap region size are considered.
  virtual const uint max_search_depth() const { return 1; }
};

#endif // SHARE_VM_GC_G1_MEMORY_NODE_MANAGER_HPP