mitsuba/include/mitsuba/core/mempool.h

96 lines
2.5 KiB
C++

/*
This file is part of Mitsuba, a physically based rendering system.
Copyright (c) 2007-2011 by Wenzel Jakob and others.
Mitsuba is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License Version 3
as published by the Free Software Foundation.
Mitsuba is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#if !defined(__MEMPOOL_H)
#define __MEMPOOL_H
#include <mitsuba/mitsuba.h>
MTS_NAMESPACE_BEGIN
/**
* \brief Basic memory pool for efficient allocation and deallocation
* of objects of the same type.
*
* This class attempts to keep most instances contiguous in memory, while
* having only minimal interaction with the underlying allocator.
*
* \ingroup libcore
*/
template <typename T> class MemoryPool {
public:
/// Create a new memory pool with aninitial set of 128 entries
MemoryPool(size_t nEntries = 128) : m_size(0) {
increaseCapacity(nEntries);
}
/// Destruct the memory pool and release all entries
~MemoryPool() {
for (size_t i=0; i<m_cleanup.size(); ++i)
delete[] m_cleanup[i];
}
/// Acquire an entry
inline T *alloc() {
if (EXPECT_NOT_TAKEN(m_free.empty()))
increaseCapacity();
T *result = m_free.back();
m_free.pop_back();
return result;
}
// void ensureNotContained(T *ptr) {
// if (std::find(m_free.begin(), m_free.end(), ptr) != m_free.end())
// SLog(EError, "Memory pool inconsistency()");
// }
/// Release an entry
inline void release(T *ptr) {
// if (std::find(m_free.begin(), m_free.end(), ptr) != m_free.end())
// SLog(EError, "Memory pool inconsistency in release()");
m_free.push_back(ptr);
}
/// Return the total size of the memory pool
inline size_t getSize() const {
return m_size;
}
/// Check if every entry has been released
bool isUnused() const {
return m_free.size() == m_size;
}
private:
void increaseCapacity(size_t nEntries = 128) {
T *ptr = new T[nEntries];
for (size_t i=0; i<nEntries; ++i)
m_free.push_back(&ptr[i]);
m_cleanup.push_back(ptr);
m_size += nEntries;
}
private:
std::vector<T *> m_free;
std::vector<T *> m_cleanup;
size_t m_size;
};
MTS_NAMESPACE_END
#endif /* __MEMPOOL_H */