Skip site navigation (1)Skip section navigation (2)

  
 
  

home | help
rte_memzone.h(3)		      DPDK			rte_memzone.h(3)

NAME
     rte_memzone.h

SYNOPSIS
     #include <stdio.h>
     #include <rte_memory.h>
     #include <rte_common.h>

   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
     int rte_memzone_max_set (size_t max)
     size_t rte_memzone_max_get (void)
     const  struct  rte_memzone  * rte_memzone_reserve (const char *name, size_t
	 len, int socket_id, unsigned flags)
     const struct rte_memzone * rte_memzone_reserve_aligned (const  char  *name,
	 size_t len, int socket_id, unsigned flags, unsigned align)
     const  struct  rte_memzone * rte_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_memzone * rte_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
   #define RTE_MEMZONE_2MB   0x00000001
     Use 2MB pages.

     Definition at line 33 of file rte_memzone.h.

   #define RTE_MEMZONE_1GB   0x00000002
     Use 1GB pages.

     Definition at line 34 of file rte_memzone.h.

   #define RTE_MEMZONE_16MB   0x00000100
     Use 16MB pages.

     Definition at line 35 of file rte_memzone.h.

   #define RTE_MEMZONE_16GB   0x00000200
     Use 16GB pages.

     Definition at line 36 of file rte_memzone.h.

   #define RTE_MEMZONE_256KB   0x00010000
     Use 256KB pages.

     Definition at line 37 of file rte_memzone.h.

   #define RTE_MEMZONE_256MB   0x00020000
     Use 256MB pages.

     Definition at line 38 of file rte_memzone.h.

   #define RTE_MEMZONE_512MB   0x00040000
     Use 512MB pages.

     Definition at line 39 of file rte_memzone.h.

   #define RTE_MEMZONE_4GB   0x00080000
     Use 4GB pages.

     Definition at line 40 of file rte_memzone.h.

   #define RTE_MEMZONE_SIZE_HINT_ONLY	0x00000004
     Use available page size

     Definition at line 41 of file rte_memzone.h.

   #define RTE_MEMZONE_IOVA_CONTIG   0x00100000
     Ask for IOVA-contiguous memzone.

     Definition at line 42 of file rte_memzone.h.

   #define RTE_MEMZONE_NAMESIZE   32
     Maximum length of memory zone name.

     Definition at line 50 of file rte_memzone.h.

Function Documentation
   int rte_memzone_max_set (size_t max)
     Set the maximum number of memzones.

     This function can only be called prior to rte_eal_init().

     Parameters
	 max Maximum number of memzones.

     Returns
	 0 on success, -1 otherwise.

   size_t rte_memzone_max_get (void)
     Get the maximum number of memzones.

     Note
	 : The maximum value will not change after calling rte_eal_init().

     Returns
	 Maximum number of memzones.

   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 mem-
	 zones	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
	 name The name of the memzone. If it already exists, the  function  will
	 fail and return NULL.
	 len The size of the memory to be reserved. If it is 0, the biggest con-
	 tiguous zone will be reserved.
	 socket_id  The  socket identifier in the case of NUMA. The value can be
	 SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
	 flags The 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 hard-
	   ware 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 struc-
	   ture

	 * 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

   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  bound-
     ary.

     This  function reserves some memory with alignment on a specified boundary,
     and returns a pointer to a correctly filled memzone descriptor. If the  al-
     location  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 mem-
	 zones 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
	 name  The  name of the memzone. If it already exists, the function will
	 fail and return NULL.
	 len The size of the memory to be reserved. If it is 0, the biggest con-
	 tiguous zone will be reserved.
	 socket_id The socket identifier in the case of NUMA. The value  can  be
	 SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
	 flags	The 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  hard-
	   ware rings etc.

	 align Alignment 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 struc-
	   ture

	 * 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

   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  al-
     location  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 mem-
	 zones	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
	 name The name of the memzone. If it already exists, the  function  will
	 fail and return NULL.
	 len The size of the memory to be reserved. If it is 0, the biggest con-
	 tiguous zone will be reserved.
	 socket_id  The  socket identifier in the case of NUMA. The value can be
	 SOCKET_ID_ANY if there is no NUMA constraint for the reserved zone.
	 flags The 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 hard-
	   ware rings etc.

	 align Alignment for resulting memzone. Must be a power of 2.
	 bound Boundary 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 struc-
	   ture

	 * 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

   int rte_memzone_free (const struct rte_memzone * mz)
     Free a memzone.

     Parameters
	 mz A pointer to the memzone

     Returns
	 -EINVAL - invalid parameter. 0 - success

   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
	 name The name of the memzone.

     Returns
	 A pointer to a read-only memzone descriptor.

   void rte_memzone_dump (FILE * f)
     Dump all reserved memzones to a file.

     Parameters
	 f A pointer to a file for output

   void rte_memzone_walk (void(*)(const struct rte_memzone *, void  *arg)  func,
     void * arg)
     Walk list of all memzones

     Parameters
	 func Iterator function
	 arg Argument passed to iterator

Author
     Generated automatically by Doxygen for DPDK from the source code.

Version 25.11.0 		 Thu Aug 27 2026		rte_memzone.h(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=RTE_MEMZONE_2MB&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help