rte_fbk_hash.h File Reference

#include <stdint.h>
#include <errno.h>
#include <sys/queue.h>
#include <string.h>
#include <rte_jhash.h>

Go to the source code of this file.

Data Structures
struct	rte_fbk_hash_params
union	rte_fbk_hash_entry
struct	rte_fbk_hash_table

Macros
#define	RTE_FBK_HASH_INIT_VAL_DEFAULT   0xFFFFFFFF
#define	RTE_FBK_HASH_ENTRIES_MAX   (1 << 20)
#define	RTE_FBK_HASH_ENTRIES_PER_BUCKET_MAX   256
#define	RTE_FBK_HASH_NAMESIZE   32

Typedefs
typedef uint32_t(*	rte_fbk_hash_fn )(uint32_t key, uint32_t init_val)

Functions
static uint32_t	rte_fbk_hash_get_bucket (const struct rte_fbk_hash_table *ht, uint32_t key)
static int	rte_fbk_hash_add_key_with_bucket (struct rte_fbk_hash_table *ht, uint32_t key, uint16_t value, uint32_t bucket)
static int	rte_fbk_hash_add_key (struct rte_fbk_hash_table *ht, uint32_t key, uint16_t value)
static int	rte_fbk_hash_delete_key_with_bucket (struct rte_fbk_hash_table *ht, uint32_t key, uint32_t bucket)
static int	rte_fbk_hash_delete_key (struct rte_fbk_hash_table *ht, uint32_t key)
static int	rte_fbk_hash_lookup_with_bucket (const struct rte_fbk_hash_table *ht, uint32_t key, uint32_t bucket)
static int	rte_fbk_hash_lookup (const struct rte_fbk_hash_table *ht, uint32_t key)
static void	rte_fbk_hash_clear_all (struct rte_fbk_hash_table *ht)
static double	rte_fbk_hash_get_load_factor (struct rte_fbk_hash_table *ht)
struct rte_fbk_hash_table *	rte_fbk_hash_find_existing (const char *name)
struct rte_fbk_hash_table *	rte_fbk_hash_create (const struct rte_fbk_hash_params *params)
void	rte_fbk_hash_free (struct rte_fbk_hash_table *ht)

Detailed Description

This is a hash table implementation for four byte keys (fbk).

Note that the return value of the add function should always be checked as, if a bucket is full, the key is not added even if there is space in other buckets. This keeps the lookup function very simple and therefore fast.

Definition in file rte_fbk_hash.h.

Macro Definition Documentation

#define RTE_FBK_HASH_INIT_VAL_DEFAULT   0xFFFFFFFF

Initialising value used when calculating hash.

Definition at line 70 of file rte_fbk_hash.h.

#define RTE_FBK_HASH_ENTRIES_MAX   (1 << 20)

The maximum number of entries in the hash table that is supported.

Definition at line 74 of file rte_fbk_hash.h.

#define RTE_FBK_HASH_ENTRIES_PER_BUCKET_MAX   256

The maximum number of entries in each bucket that is supported.

Definition at line 77 of file rte_fbk_hash.h.

#define RTE_FBK_HASH_NAMESIZE   32

Maximum size of string for naming the hash.

Definition at line 80 of file rte_fbk_hash.h.

Typedef Documentation

typedef uint32_t(* rte_fbk_hash_fn)(uint32_t key, uint32_t init_val)

Type of function that can be used for calculating the hash value.

Definition at line 83 of file rte_fbk_hash.h.

Function Documentation

static uint32_t rte_fbk_hash_get_bucket ( const struct rte_fbk_hash_table *  ht, uint32_t  key  )

inlinestatic

Find the offset into hash table of the bucket containing a particular key.

Parameters

ht	Pointer to hash table.
key	Key to calculate bucket for.

Returns

Offset into hash table.

Definition at line 132 of file rte_fbk_hash.h.

static int rte_fbk_hash_add_key_with_bucket ( struct rte_fbk_hash_table *  ht, uint32_t  key, uint16_t  value, uint32_t  bucket  )

inlinestatic

Add a key to an existing hash table with bucket id. This operation is not multi-thread safe and should only be called from one thread.

Parameters

ht	Hash table to add the key to.
key	Key to add to the hash table.
value	Value to associate with key.
bucket	Bucket to associate with key.

Returns

0 if ok, or negative value on error.

Definition at line 155 of file rte_fbk_hash.h.

static int rte_fbk_hash_add_key ( struct rte_fbk_hash_table *  ht, uint32_t  key, uint16_t  value  )

inlinestatic

Add a key to an existing hash table. This operation is not multi-thread safe and should only be called from one thread.

Parameters

ht	Hash table to add the key to.
key	Key to add to the hash table.
value	Value to associate with key.

Returns

0 if ok, or negative value on error.

Examples:

ipv4_multicast/main.c.

Definition at line 200 of file rte_fbk_hash.h.

static int rte_fbk_hash_delete_key_with_bucket ( struct rte_fbk_hash_table *  ht, uint32_t  key, uint32_t  bucket  )

inlinestatic

Remove a key with a given bucket id from an existing hash table. This operation is not multi-thread safe and should only be called from one thread.

Parameters

ht	Hash table to remove the key from.
key	Key to remove from the hash table.
bucket	Bucket id associate with key.

Returns

0 if ok, or negative value on error.

Definition at line 222 of file rte_fbk_hash.h.

static int rte_fbk_hash_delete_key ( struct rte_fbk_hash_table *  ht, uint32_t  key  )

inlinestatic

Remove a key from an existing hash table. This operation is not multi-thread safe and should only be called from one thread.

Parameters

ht	Hash table to remove the key from.
key	Key to remove from the hash table.

Returns

0 if ok, or negative value on error.

Definition at line 265 of file rte_fbk_hash.h.

static int rte_fbk_hash_lookup_with_bucket ( const struct rte_fbk_hash_table *  ht, uint32_t  key, uint32_t  bucket  )

inlinestatic

Find a key in the hash table with a given bucketid. This operation is multi-thread safe.

Parameters

ht	Hash table to look in.
key	Key to find.
bucket	Bucket associate to the key.

Returns

The value that was associated with the key, or negative value on error.

Definition at line 285 of file rte_fbk_hash.h.

static int rte_fbk_hash_lookup ( const struct rte_fbk_hash_table *  ht, uint32_t  key  )

inlinestatic

Find a key in the hash table. This operation is multi-thread safe.

Parameters

ht	Hash table to look in.
key	Key to find.

Returns

The value that was associated with the key, or negative value on error.

Examples:

ipv4_multicast/main.c.

Definition at line 315 of file rte_fbk_hash.h.

static void rte_fbk_hash_clear_all ( struct rte_fbk_hash_table *  ht )

inlinestatic

Delete all entries in a hash table. This operation is not multi-thread safe and should only be called from one thread.

Parameters

ht	Hash table to delete entries in.

Definition at line 329 of file rte_fbk_hash.h.

static double rte_fbk_hash_get_load_factor ( struct rte_fbk_hash_table *  ht )

inlinestatic

Find what fraction of entries are being used.

Parameters

ht	Hash table to find how many entries are being used in.

Returns

Load factor of the hash table, or negative value on error.

Definition at line 344 of file rte_fbk_hash.h.

struct rte_fbk_hash_table* rte_fbk_hash_find_existing ( const char *  name )

read

Performs a lookup for an existing hash table, and returns a pointer to the table if found.

Parameters

name	Name of the hash table to find

Returns

pointer to hash table structure or NULL on error with rte_errno set appropriately. Possible rte_errno values include:

• ENOENT - required entry not available to return.

struct rte_fbk_hash_table* rte_fbk_hash_create ( const struct rte_fbk_hash_params *  params )

read

Create a new hash table for use with four byte keys.

Parameters

params

Parameters used in creation of hash table.

Returns

Pointer to hash table structure that is used in future hash table operations, or NULL on error with rte_errno set appropriately. Possible rte_errno error values include:

• E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
• E_RTE_SECONDARY - function was called from a secondary process instance
• EINVAL - invalid parameter value passed to function
• 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

Examples:

ipv4_multicast/main.c.

void rte_fbk_hash_free

(

struct rte_fbk_hash_table *

ht

)

Free all memory used by a hash table. Has no effect on hash tables allocated in memory zones

Parameters

ht	Hash table to deallocate.