sla.h File Reference

Detailed Description

Author

hacatu

Version

0.3.0 Simple slab allocator. Allows for efficient allocation of objects of a fixed size

Definition in file sla.h.

Go to the source code of this file.

Data Structures
struct	cr8r_sla
	Slab allocator. More...

Functions
bool	cr8r_sla_init (cr8r_sla *self, uint64_t elem_size, uint64_t cap)
	Initialize a slab allocator. More...
void	cr8r_sla_delete (cr8r_sla *self)
	Delete a slab allocator. More...
void *	cr8r_sla_alloc (cr8r_sla *self)
	Allocate an object. More...
void	cr8r_sla_free (cr8r_sla *self, void *p)
	Frees and object which was previously allocated by cr8r_sla_alloc. More...

Function Documentation

cr8r_sla_init()

bool cr8r_sla_init	(	cr8r_sla *	self,
		uint64_t	elem_size,
		uint64_t	cap
	)

Initialize a slab allocator.

Parameters

[out]	self	slab allocator to initialize
[in]	elem_size	size of a single element in bytes. allocations returned will be this big. must be at least sizeof(void*)
[in]	cap	the number of elements to reserve space for initially, which is all reserved in a single "slab". must be at least 1

Returns

1 on success, 0 on failure (allocation failure)

cr8r_sla_delete()

void cr8r_sla_delete

(

cr8r_sla *

self

)

Delete a slab allocator.

Frees all slabs and zeros out capacity/len. The allocator should not be used again after this, unless it is reinitialized.

Parameters

[in,out]

self

slab allocator to delete

cr8r_sla_alloc()

void* cr8r_sla_alloc

(

cr8r_sla *

self

)

Allocate an object.

If successful, the returned pointer will point to uninitialized memory with the element size of the slab allocator.

Parameters

[in]

self

slab allocator to allocate from

Returns

pointer to useable uninitialized memory of the slab allocator's element size, or NULL if no unallocated elements are available and allocation of more backing storage fails.

cr8r_sla_free()

void cr8r_sla_free	(	cr8r_sla *	self,
		void *	p
	)

Frees and object which was previously allocated by cr8r_sla_alloc.

The slab allocator does not check if this is indeed an allocated block, because doing so would make deallocation an O(log(n)) operation and require a larger minimum element size be enforced. It is technically possible to "abuse" this function to "free" pointers to elements from some other backing store, and then the allocator will hand these out together with elements actually from the underlying slabs. However, this should typically not be done because it ties the slab allocator to an external backing store that is not managed by it.

Parameters

[in]	self	slab allocator to work with
[in]	p	pointer to free