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#ifndef SHARE_VM_SERVICES_G1MEMORYPOOL_HPP

#define SHARE_VM_SERVICES_G1MEMORYPOOL_HPP

#ifndef SERIALGC

#include "services/memoryPool.hpp"

#include "services/memoryUsage.hpp"

#endif

class G1CollectedHeap;

// This file contains the three classes that represent the memory

// pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and

// G1OldGenPool. In G1, unlike our other GCs, we do not have a

// physical space for each of those spaces. Instead, we allocate

// regions for all three spaces out of a single pool of regions (that

// pool basically covers the entire heap). As a result, the eden,

// survivor, and old gen are considered logical spaces in G1, as each

// is a set of non-contiguous regions. This is also reflected in the

// way we map them to memory pools here. The easiest way to have done

// this would have been to map the entire G1 heap to a single memory

// pool. However, it's helpful to show how large the eden and survivor

// get, as this does affect the performance and behavior of G1. Which

// is why we introduce the three memory pools implemented here.

//

//

// This class is shared by the three G1 memory pool classes

// (G1EdenPool, G1SurvivorPool, G1OldGenPool). Given that the way we

// calculate used / committed bytes for these three pools is related

// (see comment above), we put the calculations in this class so that

// we can easily share them among the subclasses.

class G1MemoryPoolSuper : public CollectedMemoryPool {

protected:

  G1CollectedHeap* _g1h;

  // Would only be called from subclasses.

  G1MemoryPoolSuper(G1CollectedHeap* g1h,

                    const char* name,

                    size_t init_size,

                    bool support_usage_threshold);

  // The reason why all the code is in static methods is so that it

  // can be safely called from the constructors of the subclasses.

  static size_t undefined_max() {

    return (size_t) -1;

  }

  static size_t eden_space_committed(G1CollectedHeap* g1h);

  static size_t eden_space_used(G1CollectedHeap* g1h);

  static size_t survivor_space_committed(G1CollectedHeap* g1h);

  static size_t survivor_space_used(G1CollectedHeap* g1h);

  static size_t old_space_committed(G1CollectedHeap* g1h);

  static size_t old_space_used(G1CollectedHeap* g1h);

};

// Memory pool that represents the G1 eden.

class G1EdenPool : public G1MemoryPoolSuper {

public:

  G1EdenPool(G1CollectedHeap* g1h);

  size_t used_in_bytes() {

    return eden_space_used(_g1h);

  }

  size_t max_size() const {

    return undefined_max();

  }

  MemoryUsage get_memory_usage();

};

// Memory pool that represents the G1 survivor.

class G1SurvivorPool : public G1MemoryPoolSuper {

public:

  G1SurvivorPool(G1CollectedHeap* g1h);

  size_t used_in_bytes() {

    return survivor_space_used(_g1h);

  }

  size_t max_size() const {

    return undefined_max();

  }

  MemoryUsage get_memory_usage();

};

// Memory pool that represents the G1 old gen.

class G1OldGenPool : public G1MemoryPoolSuper {

public:

  G1OldGenPool(G1CollectedHeap* g1h);

  size_t used_in_bytes() {

    return old_space_used(_g1h);

  }

  size_t max_size() const {

    return undefined_max();

  }

  MemoryUsage get_memory_usage();

};

#endif // SHARE_VM_SERVICES_G1MEMORYPOOL_HPP