---
name: "rte_memory.h"
section: "3"
platform: "linux"
package: "dpdk-doc"
version: "24.11.4-0+deb13u1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/rte_memory.h"
---

# rte\_memory.h(3)

## NAME

rte\_memory.h

## SYNOPSIS

`#include <stdint.h>`\
 `#include <stddef.h>`\
 `#include <stdio.h>`\
 `#include <rte_bitops.h>`\
 `#include <rte_common.h>`\
 `#include <rte_config.h>`\
 `#include <rte_eal_memconfig.h>`\
 `#include <rte_fbarray.h>`\

### Data Structures

struct **rte\_memseg**\
 struct **rte\_memseg\_list**\

### Macros

\#define **SOCKET\_ID\_ANY**   -1\
 \#define **RTE\_MEMSEG\_FLAG\_DO\_NOT\_FREE**   **RTE\_BIT32**(0)\
 \#define **RTE\_MEMSEG\_FLAG\_DIRTY**   **RTE\_BIT32**(1)\
 \#define **RTE\_MEM\_EVENT\_CALLBACK\_NAME\_LEN**   64\
 \#define **RTE\_MEM\_ALLOC\_VALIDATOR\_NAME\_LEN**   64\

### Typedefs

**typedef** int(\* **rte\_memseg\_walk\_t**) (const struct **rte\_memseg\_list** \*msl, const struct **rte\_memseg** \*ms, void \*arg)\
 **typedef** int(\* **rte\_memseg\_contig\_walk\_t**) (const struct **rte\_memseg\_list** \*msl, const struct **rte\_memseg** \*ms, size\_t len, void \*arg)\
 **typedef** int(\* **rte\_memseg\_list\_walk\_t**) (const struct **rte\_memseg\_list** \*msl, void \*arg)\
 **typedef** void(\* **rte\_mem\_event\_callback\_t**) (enum **rte\_mem\_event** event\_type, const void \*addr, size\_t len, void \*arg)\
 **typedef** int(\* **rte\_mem\_alloc\_validator\_t**) (int socket\_id, size\_t cur\_limit, size\_t new\_len)\

### Enumerations

enum **rte\_mem\_event** { **RTE\_MEM\_EVENT\_ALLOC** = 0, **RTE\_MEM\_EVENT\_FREE** }\

### Functions

int **rte\_mem\_lock\_page** (const void \*virt)\
 **phys\_addr\_t** **rte\_mem\_virt2phy** (const void \*virt)\
 **rte\_iova\_t** **rte\_mem\_virt2iova** (const void \*virt)\
 void \* **rte\_mem\_iova2virt** (**rte\_iova\_t** iova)\
 struct **rte\_memseg** \* **rte\_mem\_virt2memseg** (const void \*virt, const struct **rte\_memseg\_list** \*msl)\
 struct **rte\_memseg\_list** \* **rte\_mem\_virt2memseg\_list** (const void \*virt)\
 int **rte\_memseg\_walk** (**rte\_memseg\_walk\_t** func, void \*arg)\
 int **rte\_memseg\_contig\_walk** (**rte\_memseg\_contig\_walk\_t** func, void \*arg)\
 int **rte\_memseg\_list\_walk** (**rte\_memseg\_list\_walk\_t** func, void \*arg) \_\_rte\_locks\_excluded(**rte\_mcfg\_mem\_get\_lock**())\
 int **rte\_memseg\_walk\_thread\_unsafe** (**rte\_memseg\_walk\_t** func, void \*arg)\
 int **rte\_memseg\_contig\_walk\_thread\_unsafe** (**rte\_memseg\_contig\_walk\_t** func, void \*arg)\
 int **rte\_memseg\_list\_walk\_thread\_unsafe** (**rte\_memseg\_list\_walk\_t** func, void \*arg)\
 int **rte\_memseg\_get\_fd** (const struct **rte\_memseg** \*ms)\
 int **rte\_memseg\_get\_fd\_thread\_unsafe** (const struct **rte\_memseg** \*ms)\
 int **rte\_memseg\_get\_fd\_offset** (const struct **rte\_memseg** \*ms, size\_t \*offset)\
 int **rte\_memseg\_get\_fd\_offset\_thread\_unsafe** (const struct **rte\_memseg** \*ms, size\_t \*offset)\
 int **rte\_extmem\_register** (void \*va\_addr, size\_t len, **rte\_iova\_t** iova\_addrs\[\], unsigned int n\_pages, size\_t page\_sz)\
 int **rte\_extmem\_unregister** (void \*va\_addr, size\_t len)\
 int **rte\_extmem\_attach** (void \*va\_addr, size\_t len)\
 int **rte\_extmem\_detach** (void \*va\_addr, size\_t len)\
 void **rte\_dump\_physmem\_layout** (FILE \*f)\
 uint64\_t **rte\_eal\_get\_physmem\_size** (void)\
 unsigned **rte\_memory\_get\_nchannel** (void)\
 unsigned **rte\_memory\_get\_nrank** (void)\
 int **rte\_mem\_check\_dma\_mask** (uint8\_t maskbits)\
 int **rte\_mem\_check\_dma\_mask\_thread\_unsafe** (uint8\_t maskbits)\
 void **rte\_mem\_set\_dma\_mask** (uint8\_t maskbits)\
 int **rte\_eal\_using\_phys\_addrs** (void)\
 int **rte\_mem\_event\_callback\_register** (const char \*name, **rte\_mem\_event\_callback\_t** clb, void \*arg)\
 int **rte\_mem\_event\_callback\_unregister** (const char \*name, void \*arg)\
 int **rte\_mem\_alloc\_validator\_register** (const char \*name, **rte\_mem\_alloc\_validator\_t** clb, int socket\_id, size\_t limit)\
 Register validator callback for memory allocations.  int **rte\_mem\_alloc\_validator\_unregister** (const char \*name, int socket\_id)\
 Unregister validator callback for memory allocations.

## Detailed Description

Memory-related RTE API.

Definition in file **rte\_memory.h**.

## Macro Definition Documentation

### #define SOCKET\_ID\_ANY -1

Any NUMA socket.

Definition at line **39** of file **rte\_memory.h**.

### #define RTE\_MEMSEG\_FLAG\_DO\_NOT\_FREE RTE\_BIT32(0)

Prevent this segment from being freed back to the OS.

Definition at line **42** of file **rte\_memory.h**.

### #define RTE\_MEMSEG\_FLAG\_DIRTY RTE\_BIT32(1)

This segment is not filled with zeros.

Definition at line **44** of file **rte\_memory.h**.

### #define RTE\_MEM\_EVENT\_CALLBACK\_NAME\_LEN 64

maximum length of callback name

Definition at line **610** of file **rte\_memory.h**.

### #define RTE\_MEM\_ALLOC\_VALIDATOR\_NAME\_LEN 64

maximum length of alloc validator name

Definition at line **666** of file **rte\_memory.h**.

## Typedef Documentation

### typedef int(\* rte\_memseg\_walk\_t) (const struct rte\_memseg\_list \*msl, const struct rte\_memseg \*ms, void \*arg)

Memseg walk function prototype.

Returning 0 will continue walk Returning 1 will stop the walk Returning -1 will stop the walk and report error

Definition at line **167** of file **rte\_memory.h**.

### typedef int(\* rte\_memseg\_contig\_walk\_t) (const struct rte\_memseg\_list \*msl, const struct rte\_memseg \*ms, size\_t len, void \*arg)

Memseg contig walk function prototype. This will trigger a callback on every VA-contiguous area starting at memseg `ms`, so total valid VA space at each callback call will be \[`ms->addr`, `ms->addr + len`).

Returning 0 will continue walk Returning 1 will stop the walk Returning -1 will stop the walk and report error

Definition at line **179** of file **rte\_memory.h**.

### typedef int(\* rte\_memseg\_list\_walk\_t) (const struct rte\_memseg\_list \*msl, void \*arg)

Memseg list walk function prototype. This will trigger a callback on every allocated memseg list.

Returning 0 will continue walk Returning 1 will stop the walk Returning -1 will stop the walk and report error

Definition at line **190** of file **rte\_memory.h**.

### typedef void(\* rte\_mem\_event\_callback\_t) (enum rte\_mem\_event event\_type, const void \*addr, size\_t len, void \*arg)

Function typedef used to register callbacks for memory events.

Definition at line **615** of file **rte\_memory.h**.

### typedef int(\* rte\_mem\_alloc\_validator\_t) (int socket\_id, size\_t cur\_limit, size\_t new\_len)

Function typedef used to register memory allocation validation callbacks.

Returning 0 will allow allocation attempt to continue. Returning -1 will prevent allocation from succeeding.

Definition at line **673** of file **rte\_memory.h**.

## Enumeration Type Documentation

### enum rte\_mem\_event

Enum indicating which kind of memory event has happened. Used by callbacks to distinguish between memory allocations and deallocations.

**Enumerator**

- *RTE\_MEM\_EVENT\_ALLOC*

  *Allocation event.*

- *RTE\_MEM\_EVENT\_FREE*

  *Deallocation event.*

*Definition at line* **605** *of file* **rte\_memory.h***.*

## Function Documentation

### int rte\_mem\_lock\_page (const void \* virt)

*Lock page in physical memory and prevent from swapping.*

**Parameters**

*virt The virtual address.*

**Returns**

*0 on success, negative on error.*

### phys\_addr\_t rte\_mem\_virt2phy (const void \* virt)

*Get physical address of any mapped virtual address in the current process. It is found by browsing the /proc/self/pagemap special file. The page must be locked.*

**Parameters**

*virt The virtual address.*

**Returns**

*The physical address or RTE\_BAD\_IOVA on error.*

### rte\_iova\_t rte\_mem\_virt2iova (const void \* virt)

*Get IO virtual address of any mapped virtual address in the current process.*

**Note**

*This function will not check internal page table. Instead, in IOVA as PA mode, it will fall back to getting real physical address (which may not match the expected IOVA, such as what was specified for external memory).*

**Parameters**

*virt The virtual address.*

**Returns**

*The IO address or RTE\_BAD\_IOVA on error.*

### void \* rte\_mem\_iova2virt (rte\_iova\_t iova)

*Get virtual memory address corresponding to iova address.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

**Parameters**

*iova The iova address.*

**Returns**

*Virtual address corresponding to iova address (or NULL if address does not exist within DPDK memory map).*

### struct rte\_memseg \* rte\_mem\_virt2memseg (const void \* virt, const struct rte\_memseg\_list \* msl)

*Get memseg to which a particular virtual address belongs.*

**Parameters**

*virt The virtual address.* \
 *msl The memseg list in which to look up based on* `virt` *address (can be NULL).*

**Returns**

*Memseg pointer on success, or NULL on error.*

### struct rte\_memseg\_list \* rte\_mem\_virt2memseg\_list (const void \* virt)

*Get memseg list corresponding to virtual memory address.*

**Parameters**

*virt The virtual address.*

**Returns**

*Memseg list to which this virtual address belongs to.*

### int rte\_memseg\_walk (rte\_memseg\_walk\_t func, void \* arg)

*Walk list of all memsegs.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

*This function will also walk through externally allocated segments. It is up to the user to decide whether to skip through these segments.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_contig\_walk (rte\_memseg\_contig\_walk\_t func, void \* arg)

*Walk each VA-contiguous area.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

*This function will also walk through externally allocated segments. It is up to the user to decide whether to skip through these segments.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_list\_walk (rte\_memseg\_list\_walk\_t func, void \* arg)

*Walk each allocated memseg list.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

*This function will also walk through externally allocated segments. It is up to the user to decide whether to skip through these segments.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_walk\_thread\_unsafe (rte\_memseg\_walk\_t func, void \* arg)

*Walk list of all memsegs without performing any locking.*

**Note**

*This function does not perform any locking, and is only safe to call from within memory-related callback functions.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_contig\_walk\_thread\_unsafe (rte\_memseg\_contig\_walk\_t func, void \* arg)

*Walk each VA-contiguous area without performing any locking.*

**Note**

*This function does not perform any locking, and is only safe to call from within memory-related callback functions.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_list\_walk\_thread\_unsafe (rte\_memseg\_list\_walk\_t func, void \* arg)

*Walk each allocated memseg list without performing any locking.*

**Note**

*This function does not perform any locking, and is only safe to call from within memory-related callback functions.*

**Parameters**

*func Iterator function* \
 *arg Argument passed to iterator*

**Returns**

*0 if walked over the entire list 1 if stopped by the user -1 if user function reported error*

### int rte\_memseg\_get\_fd (const struct rte\_memseg \* ms)

*Return file descriptor associated with a particular memseg (if available).*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

*This returns an internal file descriptor. Performing any operations on this file descriptor is inherently dangerous, so it should be treated as read-only for all intents and purposes.*

**Parameters**

*ms A pointer to memseg for which to get file descriptor.*

**Returns**

*Valid file descriptor in case of success. -1 in case of error, with* `rte_errno` *set to the following values:*

- •

  *EINVAL -* `ms` *pointer was NULL or did not point to a valid memseg*

- •

  *ENODEV -* `ms` *fd is not available*

- •

  *ENOENT -* `ms` *is an unused segment*

- •

  *ENOTSUP - segment fd's are not supported*

### int rte\_memseg\_get\_fd\_thread\_unsafe (const struct rte\_memseg \* ms)

*Return file descriptor associated with a particular memseg (if available).*

**Note**

*This function does not perform any locking, and is only safe to call from within memory-related callback functions.*

*This returns an internal file descriptor. Performing any operations on this file descriptor is inherently dangerous, so it should be treated as read-only for all intents and purposes.*

**Parameters**

*ms A pointer to memseg for which to get file descriptor.*

**Returns**

*Valid file descriptor in case of success. -1 in case of error, with* `rte_errno` *set to the following values:*

- •

  *EINVAL -* `ms` *pointer was NULL or did not point to a valid memseg*

- •

  *ENODEV -* `ms` *fd is not available*

- •

  *ENOENT -* `ms` *is an unused segment*

- •

  *ENOTSUP - segment fd's are not supported*

### int rte\_memseg\_get\_fd\_offset (const struct rte\_memseg \* ms, size\_t \* offset)

*Get offset into segment file descriptor associated with a particular memseg (if available).*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

**Parameters**

*ms A pointer to memseg for which to get file descriptor.* \
 *offset A pointer to offset value where the result will be stored.*

**Returns**

*Valid file descriptor in case of success. -1 in case of error, with* `rte_errno` *set to the following values:*

- •

  *EINVAL -* `ms` *pointer was NULL or did not point to a valid memseg*

- •

  *EINVAL -* `offset` *pointer was NULL*

- •

  *ENODEV -* `ms` *fd is not available*

- •

  *ENOENT -* `ms` *is an unused segment*

- •

  *ENOTSUP - segment fd's are not supported*

### int rte\_memseg\_get\_fd\_offset\_thread\_unsafe (const struct rte\_memseg \* ms, size\_t \* offset)

*Get offset into segment file descriptor associated with a particular memseg (if available).*

**Note**

*This function does not perform any locking, and is only safe to call from within memory-related callback functions.*

**Parameters**

*ms A pointer to memseg for which to get file descriptor.* \
 *offset A pointer to offset value where the result will be stored.*

**Returns**

*Valid file descriptor in case of success. -1 in case of error, with* `rte_errno` *set to the following values:*

- •

  *EINVAL -* `ms` *pointer was NULL or did not point to a valid memseg*

- •

  *EINVAL -* `offset` *pointer was NULL*

- •

  *ENODEV -* `ms` *fd is not available*

- •

  *ENOENT -* `ms` *is an unused segment*

- •

  *ENOTSUP - segment fd's are not supported*

### int rte\_extmem\_register (void \* va\_addr, size\_t len, rte\_iova\_t iova\_addrs\[\], unsigned int n\_pages, size\_t page\_sz)

*Register external memory chunk with DPDK.*

**Note**

*Using this API is mutually exclusive with* `rte_malloc` *family of API's.*

*This API will not perform any DMA mapping. It is expected that user will do that themselves.*

*Before accessing this memory in other processes, it needs to be attached in each of those processes by calling* `rte_extmem_attach` *in each other process.*

**Parameters**

*va\_addr Start of virtual area to register. Must be aligned by* `page_sz`*.* \
 *len Length of virtual area to register. Must be aligned by* `page_sz`*.* \
 *iova\_addrs Array of page IOVA addresses corresponding to each page in this memory area. Can be NULL, in which case page IOVA addresses will be set to RTE\_BAD\_IOVA.* \
 *n\_pages Number of elements in the iova\_addrs array. Ignored if* `iova_addrs` *is NULL.* \
 *page\_sz Page size of the underlying memory*

**Returns**

- •

  *0 on success*

- •

  *-1 in case of error, with rte\_errno set to one of the following: EINVAL - one of the parameters was invalid EEXIST - memory chunk is already registered ENOSPC - no more space in internal config to store a new memory chunk*

### int rte\_extmem\_unregister (void \* va\_addr, size\_t len)

*Unregister external memory chunk with DPDK.*

**Note**

*Using this API is mutually exclusive with* `rte_malloc` *family of API's.*

*This API will not perform any DMA unmapping. It is expected that user will do that themselves.*

*Before calling this function, all other processes must call* `rte_extmem_detach` *to detach from the memory area.*

**Parameters**

*va\_addr Start of virtual area to unregister* \
 *len Length of virtual area to unregister*

**Returns**

- •

  *0 on success*

- •

  *-1 in case of error, with rte\_errno set to one of the following: EINVAL - one of the parameters was invalid ENOENT - memory chunk was not found*

### int rte\_extmem\_attach (void \* va\_addr, size\_t len)

*Attach to external memory chunk registered in another process.*

**Note**

*Using this API is mutually exclusive with* `rte_malloc` *family of API's.*

*This API will not perform any DMA mapping. It is expected that user will do that themselves.*

**Parameters**

*va\_addr Start of virtual area to register* \
 *len Length of virtual area to register*

**Returns**

- •

  *0 on success*

- •

  *-1 in case of error, with rte\_errno set to one of the following: EINVAL - one of the parameters was invalid ENOENT - memory chunk was not found*

### int rte\_extmem\_detach (void \* va\_addr, size\_t len)

*Detach from external memory chunk registered in another process.*

**Note**

*Using this API is mutually exclusive with* `rte_malloc` *family of API's.*

*This API will not perform any DMA unmapping. It is expected that user will do that themselves.*

**Parameters**

*va\_addr Start of virtual area to unregister* \
 *len Length of virtual area to unregister*

**Returns**

- •

  *0 on success*

- •

  *-1 in case of error, with rte\_errno set to one of the following: EINVAL - one of the parameters was invalid ENOENT - memory chunk was not found*

### void rte\_dump\_physmem\_layout (FILE \* f)

*Dump the physical memory layout to a file.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

**Parameters**

*f A pointer to a file for output*

### uint64\_t rte\_eal\_get\_physmem\_size (void)

*Get the total amount of available physical memory.*

**Note**

*This function read-locks the memory hotplug subsystem, and thus cannot be used within memory-related callback functions.*

**Returns**

*The total amount of available physical memory in bytes.*

### unsigned rte\_memory\_get\_nchannel (void)

*Get the number of memory channels.*

**Returns**

*The number of memory channels on the system. The value is 0 if unknown or not the same on all devices.*

### unsigned rte\_memory\_get\_nrank (void)

*Get the number of memory ranks.*

**Returns**

*The number of memory ranks on the system. The value is 0 if unknown or not the same on all devices.*

### int rte\_mem\_check\_dma\_mask (uint8\_t maskbits)

*Check if all currently allocated memory segments are compliant with supplied DMA address width.*

**Parameters**

*maskbits Address width to check against.*

### int rte\_mem\_check\_dma\_mask\_thread\_unsafe (uint8\_t maskbits)

*Check if all currently allocated memory segments are compliant with supplied DMA address width. This function will use rte\_memseg\_walk\_thread\_unsafe instead of rte\_memseg\_walk implying memory\_hotplug\_lock will not be acquired avoiding deadlock during memory initialization.*

*This function is just for EAL core memory internal use. Drivers should use the previous rte\_mem\_check\_dma\_mask.*

**Parameters**

*maskbits Address width to check against.*

### void rte\_mem\_set\_dma\_mask (uint8\_t maskbits)

*Set dma mask to use once memory initialization is done. Previous functions rte\_mem\_check\_dma\_mask and rte\_mem\_check\_dma\_mask\_thread\_unsafe can not be used safely until memory has been initialized.*

### int rte\_eal\_using\_phys\_addrs (void)

*Drivers based on uio will not load unless physical addresses are obtainable. It is only possible to get physical addresses when running as a privileged user.*

**Returns**

*1 if the system is able to obtain physical addresses. 0 if using DMA addresses through an IOMMU.*

### int rte\_mem\_event\_callback\_register (const char \* name, rte\_mem\_event\_callback\_t clb, void \* arg)

*Function used to register callbacks for memory events.*

**Note**

*callbacks will happen while memory hotplug subsystem is write-locked, therefore some functions (e.g.* **rte\_memseg\_walk()) will cause a deadlock when called from within such callbacks.**

**mem event callbacks not being supported is an expected error condition, so user code needs to handle this situation. In these cases, return value will be -1, and rte\_errno will be set to ENOTSUP.**

**Parameters**

*name* **Name associated with specified callback to be added to the list.**\
 *clb* **Callback function pointer.**\
 *arg* **Argument to pass to the callback.**

**Returns**

**0 on successful callback register -1 on unsuccessful callback register, with rte\_errno value indicating reason for failure.**

### int rte\_mem\_event\_callback\_unregister (const char \* name, void \* arg)

**Function used to unregister callbacks for memory events.**

**Parameters**

*name* **Name associated with specified callback to be removed from the list.**\
 *arg* **Argument to look for among callbacks with specified callback name.**

**Returns**

**0 on successful callback unregister -1 on unsuccessful callback unregister, with rte\_errno value indicating reason for failure.**

### int rte\_mem\_alloc\_validator\_register (const char \* name, rte\_mem\_alloc\_validator\_t clb, int socket\_id, size\_t limit)

**Register validator callback for memory allocations. Callbacks registered by this function will be called right before memory allocator is about to trigger allocation of more pages from the system if said allocation will bring total memory usage above specified limit on specified socket. User will be able to cancel pending allocation if callback returns -1.**

**Note**

**callbacks will happen while memory hotplug subsystem is write-locked, therefore some functions (e.g. rte\_memseg\_walk()) will cause a deadlock when called from within such callbacks.**

**validator callbacks not being supported is an expected error condition, so user code needs to handle this situation. In these cases, return value will be -1, and rte\_errno will be set to ENOTSUP.**

**Parameters**

*name* **Name associated with specified callback to be added to the list.**\
 *clb* **Callback function pointer.**\
 *socket\_id* **Socket ID on which to watch for allocations.**\
 *limit* **Limit above which to trigger callbacks.**

**Returns**

**0 on successful callback register -1 on unsuccessful callback register, with rte\_errno value indicating reason for failure.**

### int rte\_mem\_alloc\_validator\_unregister (const char \* name, int socket\_id)

**Unregister validator callback for memory allocations.**

**Parameters**

*name* **Name associated with specified callback to be removed from the list.**\
 *socket\_id* **Socket ID on which to watch for allocations.**

**Returns**

**0 on successful callback unregister -1 on unsuccessful callback unregister, with rte\_errno value indicating reason for failure.**

## Author

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