#include <stdlib.h>
#include <stdint.h>
#include <fcntl.h>

Include dependency graph for atlas_alloc.h:

This graph shows which files directly or indirectly include this file:

Functions
uint32_t	NVM_CreateRegion (const char *name, int flags)
	Create a named persistent region. More...

uint32_t	NVM_FindOrCreateRegion (const char name, int flags, int is_created)
	Create a persistent region with the provided name. More...

uint32_t	NVM_FindRegion (const char *name, int flags)
	Find the id of a region when it is known to exist already. More...

void	NVM_DeleteRegion (const char *name)
	Delete the region with the provided name. More...

void	NVM_CloseRegion (uint32_t rid)
	Close a persistent region. More...

void *	NVM_GetRegionRoot (uint32_t rid)
	Get the root pointer of the persistent region. More...

void	NVM_SetRegionRoot (uint32_t rid, void *root)
	Set the root pointer of an existing persistent region. More...

int	NVM_IsInRegion (void *ptr, size_t sz)
	Determines if a memory location is within a region. More...

int	isOnDifferentCacheLine (void p1, void p2)
	Determines if the addresses are on different cache lines. More...

int	isCacheLineAligned (void *p)
	Determines if a memory location is aligned to a cache line. More...

void *	nvm_alloc (size_t sz, uint32_t rid)
	Malloc style interface for allocation from a persistent region. More...

void *	nvm_calloc (size_t nmemb, size_t sz, uint32_t rid)
	Calloc style interface for allocation from a persistent region. More...

void *	nvm_realloc (void *ptr, size_t sz, uint32_t rid)
	Realloc style interface for allocation from a persistent region. More...

void	nvm_free (void *ptr)
	Deallocation interface for persistent data. More...

Function Documentation

int isCacheLineAligned ( void * p )

Determines if a memory location is aligned to a cache line.

Parameters

p	Address of memory location under consideration

Returns: Indicates whether the memory location is cache line aligned

int isOnDifferentCacheLine	(	void *	p1,
		void *	p2
	)

Determines if the addresses are on different cache lines.

Parameters

p1	First address
p2	Second address

Returns: Indicates whether the addresses are on different cache lines

The objects under consideration must not cross cache lines, otherwise this interface is inadequate.

void* nvm_alloc	(	size_t	sz,
		uint32_t	rid
	)

Malloc style interface for allocation from a persistent region.

Parameters

sz	Size of location to be allocated
rid	Id of persistent region for allocation

Returns: Address of memory location allocated

void* nvm_calloc	(	size_t	nmemb,
		size_t	sz,
		uint32_t	rid
	)

Calloc style interface for allocation from a persistent region.

Parameters

nmemb	Number of elements in the array to be allocated
sz	Size of each element
rid	Id of persistent region for allocation

Returns: Pointer to allocated memory

void NVM_CloseRegion ( uint32_t rid )

Close a persistent region.

Parameters

rid Region id

After closing, it won't be available to the calling process without calling NVM_FindOrCreateRegion. The region will stay in NVM even after calling this interface. This interface allows closing a region with normal bookkeeping.

uint32_t NVM_CreateRegion	(	const char *	name,
		int	flags
	)

Create a named persistent region.

Parameters

name	Name of the persistent region
flags	access flag (one of O_RDONLY, O_WRONLY, O_RDWR)

Returns: Id of the region created

This interface does not check for an existing entry with the same name. If a region with the same name already exists, the behavior of the program is undefined.

void NVM_DeleteRegion ( const char * name )

Delete the region with the provided name.

Parameters

name	Name of the persistent region

Use this interface to completely destroy a region. If the region does not exist, an assertion failure will occur.

uint32_t NVM_FindOrCreateRegion	(	const char *	name,
		int	flags,
		int *	is_created
	)

Create a persistent region with the provided name.

Parameters

name	Name of the persistent region
flags	access flag (one of O_RDONLY, O_WRONLY, O_RDWR)
is_created	Indicator whether the region got created as a result of the call

Returns: Id of the region found or created

If the region already exists, the existing id of the region is returned. Otherwise a region is created and its newly assigned id returned.

uint32_t NVM_FindRegion	(	const char *	name,
		int	flags
	)

Find the id of a region when it is known to exist already.

Parameters

name	Name of the persistent region
flags	access flag (one of O_RDONLY, O_WRONLY, O_RDWR)

Returns: Id of the region found

This interface should be used over NVM_FindOrCreateRegion for efficiency reasons if the region is known to exist. If a region with the provided name does not exist, an assertion failure will occur.

void nvm_free ( void * ptr )

Deallocation interface for persistent data.

Parameters

ptr	Address of memory location to be freed.

Though the usual use case would be for the location to be in persistent memory, this interface will also work for transient data. The implementation is required to transparently handle this case as well.

void* NVM_GetRegionRoot ( uint32_t rid )

Get the root pointer of the persistent region.

Parameters

rid Region id

Returns: Root pointer of the region

The region must have been created already. Currently, only one root is implemented for a given region. The idea is that anything within a region that is not reachable from the root after program termination is assumed to be garbage and can be recycled. During execution, anything within a region that is not reachable from the root or from other roots (in the GC sense) is assumed to be garbage as well.

int NVM_IsInRegion	(	void *	ptr,
		size_t	sz
	)

Determines if a memory location is within a region.

Parameters

ptr	Queried address
sz	Size of the location in bytes

Returns: 1 if within the region, otherwise 0

void* nvm_realloc	(	void *	ptr,
		size_t	sz,
		uint32_t	rid
	)

Realloc style interface for allocation from a persistent region.

Parameters

ptr	Address of memory block provided
sz	New size of allocation
rid	Id of persistent region for allocation

Returns: Pointer to re-allocated memory

void NVM_SetRegionRoot	(	uint32_t	rid,
		void *	root
	)

Set the root pointer of an existing persistent region.

Parameters

rid	Region id
root	The new root of the region

Functions

Function Documentation