DPDK  22.11.6
Data Structures | Macros | Functions
rte_memzone.h File Reference
#include <stdio.h>
#include <rte_memory.h>
#include <rte_common.h>

Go to the source code of this file.

Data Structures

struct  rte_memzone
 

Macros

#define RTE_MEMZONE_2MB   0x00000001
 
#define RTE_MEMZONE_1GB   0x00000002
 
#define RTE_MEMZONE_16MB   0x00000100
 
#define RTE_MEMZONE_16GB   0x00000200
 
#define RTE_MEMZONE_256KB   0x00010000
 
#define RTE_MEMZONE_256MB   0x00020000
 
#define RTE_MEMZONE_512MB   0x00040000
 
#define RTE_MEMZONE_4GB   0x00080000
 
#define RTE_MEMZONE_SIZE_HINT_ONLY   0x00000004
 
#define RTE_MEMZONE_IOVA_CONTIG   0x00100000
 
#define RTE_MEMZONE_NAMESIZE   32
 

Functions

const struct rte_memzonerte_memzone_reserve (const char *name, size_t len, int socket_id, unsigned flags)
 
const struct rte_memzonerte_memzone_reserve_aligned (const char *name, size_t len, int socket_id, unsigned flags, unsigned align)
 
const struct rte_memzonerte_memzone_reserve_bounded (const char *name, size_t len, int socket_id, unsigned flags, unsigned align, unsigned bound)
 
int rte_memzone_free (const struct rte_memzone *mz)
 
const struct rte_memzonerte_memzone_lookup (const char *name)
 
void rte_memzone_dump (FILE *f)
 
void rte_memzone_walk (void(*func)(const struct rte_memzone *, void *arg), void *arg)
 

Detailed Description

RTE Memzone

The goal of the memzone allocator is to reserve contiguous portions of physical memory. These zones are identified by a name.

The memzone descriptors are shared by all partitions and are located in a known place of physical memory. This zone is accessed using rte_eal_get_configuration(). The lookup (by name) of a memory zone can be done in any partition and returns the same physical address.

A reserved memory zone cannot be unreserved. The reservation shall be done at initialization time only.

Definition in file rte_memzone.h.

Macro Definition Documentation

◆ RTE_MEMZONE_2MB

#define RTE_MEMZONE_2MB   0x00000001

Use 2MB pages.

Definition at line 33 of file rte_memzone.h.

◆ RTE_MEMZONE_1GB

#define RTE_MEMZONE_1GB   0x00000002

Use 1GB pages.

Examples:
examples/ipsec-secgw/sa.c.

Definition at line 34 of file rte_memzone.h.

◆ RTE_MEMZONE_16MB

#define RTE_MEMZONE_16MB   0x00000100

Use 16MB pages.

Definition at line 35 of file rte_memzone.h.

◆ RTE_MEMZONE_16GB

#define RTE_MEMZONE_16GB   0x00000200

Use 16GB pages.

Definition at line 36 of file rte_memzone.h.

◆ RTE_MEMZONE_256KB

#define RTE_MEMZONE_256KB   0x00010000

Use 256KB pages.

Definition at line 37 of file rte_memzone.h.

◆ RTE_MEMZONE_256MB

#define RTE_MEMZONE_256MB   0x00020000

Use 256MB pages.

Definition at line 38 of file rte_memzone.h.

◆ RTE_MEMZONE_512MB

#define RTE_MEMZONE_512MB   0x00040000

Use 512MB pages.

Definition at line 39 of file rte_memzone.h.

◆ RTE_MEMZONE_4GB

#define RTE_MEMZONE_4GB   0x00080000

Use 4GB pages.

Definition at line 40 of file rte_memzone.h.

◆ RTE_MEMZONE_SIZE_HINT_ONLY

#define RTE_MEMZONE_SIZE_HINT_ONLY   0x00000004

Use available page size

Examples:
examples/ipsec-secgw/sa.c.

Definition at line 41 of file rte_memzone.h.

◆ RTE_MEMZONE_IOVA_CONTIG

#define RTE_MEMZONE_IOVA_CONTIG   0x00100000

Ask for IOVA-contiguous memzone.

Examples:
examples/ntb/ntb_fwd.c.

Definition at line 42 of file rte_memzone.h.

◆ RTE_MEMZONE_NAMESIZE

#define RTE_MEMZONE_NAMESIZE   32

Maximum length of memory zone name.

Examples:
examples/ntb/ntb_fwd.c.

Definition at line 50 of file rte_memzone.h.

Function Documentation

◆ rte_memzone_reserve()

const struct rte_memzone* rte_memzone_reserve ( const char *  name,
size_t  len,
int  socket_id,
unsigned  flags 
)

Reserve a portion of physical memory.

This function reserves some memory and returns a pointer to a correctly filled memzone descriptor. If the allocation cannot be done, return NULL.

Note
Reserving memzones with len set to 0 will only attempt to allocate memzones from memory that is already available. It will not trigger any new allocations.
: When reserving memzones with len set to 0, it is preferable to also set a valid socket_id. Setting socket_id to SOCKET_ID_ANY is supported, but will likely not yield expected results. Specifically, the resulting memzone may not necessarily be the biggest memzone available, but rather biggest memzone available on socket id corresponding to an lcore from which reservation was called.
Parameters
nameThe name of the memzone. If it already exists, the function will fail and return NULL.
lenThe size of the memory to be reserved. If it is 0, the biggest contiguous zone will be reserved.
socket_idThe socket identifier in the case of NUMA. The value can be SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
flagsThe flags parameter is used to request memzones to be taken from specifically sized hugepages.
  • RTE_MEMZONE_2MB - Reserved from 2MB pages
  • RTE_MEMZONE_1GB - Reserved from 1GB pages
  • RTE_MEMZONE_16MB - Reserved from 16MB pages
  • RTE_MEMZONE_16GB - Reserved from 16GB pages
  • RTE_MEMZONE_256KB - Reserved from 256KB pages
  • RTE_MEMZONE_256MB - Reserved from 256MB pages
  • RTE_MEMZONE_512MB - Reserved from 512MB pages
  • RTE_MEMZONE_4GB - Reserved from 4GB pages
  • RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if the requested page size is unavailable. If this flag is not set, the function will return error on an unavailable size request.
  • RTE_MEMZONE_IOVA_CONTIG - Ensure reserved memzone is IOVA-contiguous. This option should be used when allocating memory intended for hardware rings etc.
Returns
A pointer to a correctly-filled read-only memzone descriptor, or NULL on error. On error case, rte_errno will be set appropriately:
  • E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
  • ENOSPC - the maximum number of memzones has already been allocated
  • EEXIST - a memzone with the same name already exists
  • ENOMEM - no appropriate memory area found in which to create memzone
  • EINVAL - invalid parameters
Examples:
examples/ipsec-secgw/sa.c, examples/multi_process/client_server_mp/mp_server/init.c, and examples/server_node_efd/server/init.c.

◆ rte_memzone_reserve_aligned()

const struct rte_memzone* rte_memzone_reserve_aligned ( const char *  name,
size_t  len,
int  socket_id,
unsigned  flags,
unsigned  align 
)

Reserve a portion of physical memory with alignment on a specified boundary.

This function reserves some memory with alignment on a specified boundary, and returns a pointer to a correctly filled memzone descriptor. If the allocation cannot be done or if the alignment is not a power of 2, returns NULL.

Note
Reserving memzones with len set to 0 will only attempt to allocate memzones from memory that is already available. It will not trigger any new allocations.
: When reserving memzones with len set to 0, it is preferable to also set a valid socket_id. Setting socket_id to SOCKET_ID_ANY is supported, but will likely not yield expected results. Specifically, the resulting memzone may not necessarily be the biggest memzone available, but rather biggest memzone available on socket id corresponding to an lcore from which reservation was called.
Parameters
nameThe name of the memzone. If it already exists, the function will fail and return NULL.
lenThe size of the memory to be reserved. If it is 0, the biggest contiguous zone will be reserved.
socket_idThe socket identifier in the case of NUMA. The value can be SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
flagsThe flags parameter is used to request memzones to be taken from specifically sized hugepages.
  • RTE_MEMZONE_2MB - Reserved from 2MB pages
  • RTE_MEMZONE_1GB - Reserved from 1GB pages
  • RTE_MEMZONE_16MB - Reserved from 16MB pages
  • RTE_MEMZONE_16GB - Reserved from 16GB pages
  • RTE_MEMZONE_256KB - Reserved from 256KB pages
  • RTE_MEMZONE_256MB - Reserved from 256MB pages
  • RTE_MEMZONE_512MB - Reserved from 512MB pages
  • RTE_MEMZONE_4GB - Reserved from 4GB pages
  • RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if the requested page size is unavailable. If this flag is not set, the function will return error on an unavailable size request.
  • RTE_MEMZONE_IOVA_CONTIG - Ensure reserved memzone is IOVA-contiguous. This option should be used when allocating memory intended for hardware rings etc.
alignAlignment for resulting memzone. Must be a power of 2.
Returns
A pointer to a correctly-filled read-only memzone descriptor, or NULL on error. On error case, rte_errno will be set appropriately:
  • E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
  • ENOSPC - the maximum number of memzones has already been allocated
  • EEXIST - a memzone with the same name already exists
  • ENOMEM - no appropriate memory area found in which to create memzone
  • EINVAL - invalid parameters
Examples:
examples/ntb/ntb_fwd.c.

◆ rte_memzone_reserve_bounded()

const struct rte_memzone* rte_memzone_reserve_bounded ( const char *  name,
size_t  len,
int  socket_id,
unsigned  flags,
unsigned  align,
unsigned  bound 
)

Reserve a portion of physical memory with specified alignment and boundary.

This function reserves some memory with specified alignment and boundary, and returns a pointer to a correctly filled memzone descriptor. If the allocation cannot be done or if the alignment or boundary are not a power of 2, returns NULL. Memory buffer is reserved in a way, that it wouldn't cross specified boundary. That implies that requested length should be less or equal then boundary.

Note
Reserving memzones with len set to 0 will only attempt to allocate memzones from memory that is already available. It will not trigger any new allocations.
: When reserving memzones with len set to 0, it is preferable to also set a valid socket_id. Setting socket_id to SOCKET_ID_ANY is supported, but will likely not yield expected results. Specifically, the resulting memzone may not necessarily be the biggest memzone available, but rather biggest memzone available on socket id corresponding to an lcore from which reservation was called.
Parameters
nameThe name of the memzone. If it already exists, the function will fail and return NULL.
lenThe size of the memory to be reserved. If it is 0, the biggest contiguous zone will be reserved.
socket_idThe socket identifier in the case of NUMA. The value can be SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
flagsThe flags parameter is used to request memzones to be taken from specifically sized hugepages.
  • RTE_MEMZONE_2MB - Reserved from 2MB pages
  • RTE_MEMZONE_1GB - Reserved from 1GB pages
  • RTE_MEMZONE_16MB - Reserved from 16MB pages
  • RTE_MEMZONE_16GB - Reserved from 16GB pages
  • RTE_MEMZONE_256KB - Reserved from 256KB pages
  • RTE_MEMZONE_256MB - Reserved from 256MB pages
  • RTE_MEMZONE_512MB - Reserved from 512MB pages
  • RTE_MEMZONE_4GB - Reserved from 4GB pages
  • RTE_MEMZONE_SIZE_HINT_ONLY - Allow alternative page size to be used if the requested page size is unavailable. If this flag is not set, the function will return error on an unavailable size request.
  • RTE_MEMZONE_IOVA_CONTIG - Ensure reserved memzone is IOVA-contiguous. This option should be used when allocating memory intended for hardware rings etc.
alignAlignment for resulting memzone. Must be a power of 2.
boundBoundary for resulting memzone. Must be a power of 2 or zero. Zero value implies no boundary condition.
Returns
A pointer to a correctly-filled read-only memzone descriptor, or NULL on error. On error case, rte_errno will be set appropriately:
  • E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
  • ENOSPC - the maximum number of memzones has already been allocated
  • EEXIST - a memzone with the same name already exists
  • ENOMEM - no appropriate memory area found in which to create memzone
  • EINVAL - invalid parameters

◆ rte_memzone_free()

int rte_memzone_free ( const struct rte_memzone mz)

Free a memzone.

Parameters
mzA pointer to the memzone
Returns
-EINVAL - invalid parameter. 0 - success
Examples:
examples/ipsec-secgw/sa.c, and examples/ntb/ntb_fwd.c.

◆ rte_memzone_lookup()

const struct rte_memzone* rte_memzone_lookup ( const char *  name)

Lookup for a memzone.

Get a pointer to a descriptor of an already reserved memory zone identified by the name given as an argument.

Parameters
nameThe name of the memzone.
Returns
A pointer to a read-only memzone descriptor.
Examples:
examples/multi_process/client_server_mp/mp_client/client.c, and examples/server_node_efd/node/node.c.

◆ rte_memzone_dump()

void rte_memzone_dump ( FILE *  f)

Dump all reserved memzones to a file.

Parameters
fA pointer to a file for output

◆ rte_memzone_walk()

void rte_memzone_walk ( void(*)(const struct rte_memzone *, void *arg)  func,
void *  arg 
)

Walk list of all memzones

Parameters
funcIterator function
argArgument passed to iterator