e830a3d37b
Allocate the slabs for slab-allocated items to the heap, now that heap regions are aligned. This also lets the slab sizes be non-page-sized.
53 lines
1.3 KiB
C++
53 lines
1.3 KiB
C++
#pragma once
|
|
/// \file slab_allocated.h
|
|
/// A parent template class for slab-allocated objects
|
|
|
|
#include <stdlib.h>
|
|
#include <util/pointers.h>
|
|
#include <util/vector.h>
|
|
|
|
#include "memory.h"
|
|
|
|
template <typename T, size_t N>
|
|
class slab_allocated
|
|
{
|
|
public:
|
|
static constexpr size_t slab_size = N;
|
|
|
|
void * operator new(size_t size)
|
|
{
|
|
kassert(size == sizeof(T), "Slab allocator got wrong size allocation");
|
|
if (s_free.count() == 0)
|
|
allocate_chunk();
|
|
|
|
T *item = s_free.pop();
|
|
memset(item, 0, sizeof(T));
|
|
return item;
|
|
}
|
|
|
|
void operator delete(void *p) { s_free.append(reinterpret_cast<T*>(p)); }
|
|
|
|
private:
|
|
constexpr static size_t per_block = slab_size / sizeof(T);
|
|
|
|
static void allocate_chunk()
|
|
{
|
|
s_free.ensure_capacity(per_block);
|
|
|
|
uint8_t *start = new uint8_t [slab_size];
|
|
|
|
T *current = reinterpret_cast<T*>(start);
|
|
T *end = util::offset_pointer(current, slab_size);
|
|
while (current < end)
|
|
s_free.append(current++);
|
|
}
|
|
|
|
static util::vector<T*> s_free;
|
|
};
|
|
|
|
template <typename T, size_t N>
|
|
util::vector<T*> slab_allocated<T,N>::s_free;
|
|
|
|
#define DEFINE_SLAB_ALLOCATOR(type) \
|
|
template<> util::vector<typename type*> slab_allocated<typename type, type::slab_size>::s_free {};
|