rte_fbk_hash.h

Author

       Generated automatically by Doxygen for DPDK from the source code.

DPDK                                             Version 24.11.2                               rte_fbk_hash.h(3)

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.

Function Documentation

staticuint32_trte_fbk_hash_get_bucket(conststructrte_fbk_hash_table*ht,uint32_tkey)[inline],[static]
Find the offset into hash table of the bucket containing a particular key.

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

Returns
Offset into hash table.

Definition at line 94 of file rte_fbk_hash.h.

staticintrte_fbk_hash_add_key_with_bucket(structrte_fbk_hash_table*ht,uint32_tkey,uint16_tvalue,uint32_tbucket)[inline],[static]
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.

Parametersht 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 117 of file rte_fbk_hash.h.

staticintrte_fbk_hash_add_key(structrte_fbk_hash_table*ht,uint32_tkey,uint16_tvalue)[inline],[static]
Add a key to an existing hash table. This operation is not multi-thread safe and should only be called
from one thread.

Parametersht 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.

Definition at line 162 of file rte_fbk_hash.h.

staticintrte_fbk_hash_delete_key_with_bucket(structrte_fbk_hash_table*ht,uint32_tkey,uint32_tbucket)[inline],[static]
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.

Parametersht 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 184 of file rte_fbk_hash.h.

staticintrte_fbk_hash_delete_key(structrte_fbk_hash_table*ht,uint32_tkey)[inline],[static]
Remove a key from an existing hash table. This operation is not multi-thread safe and should only be
called from one thread.

Parametersht 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 227 of file rte_fbk_hash.h.

staticintrte_fbk_hash_lookup_with_bucket(conststructrte_fbk_hash_table*ht,uint32_tkey,uint32_tbucket)[inline],[static]
Find a key in the hash table with a given bucketid. This operation is multi-thread safe.

Parametersht 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 247 of file rte_fbk_hash.h.

staticintrte_fbk_hash_lookup(conststructrte_fbk_hash_table*ht,uint32_tkey)[inline],[static]
Find a key in the hash table. This operation is multi-thread safe.

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

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

Definition at line 277 of file rte_fbk_hash.h.

staticvoidrte_fbk_hash_clear_all(structrte_fbk_hash_table*ht)[inline],[static]
Delete all entries in a hash table. This operation is not multi-thread safe and should only be called
from one thread.

Parametersht Hash table to delete entries in.

Definition at line 291 of file rte_fbk_hash.h.

staticdoublerte_fbk_hash_get_load_factor(structrte_fbk_hash_table*ht)[inline],[static]
Find what fraction of entries are being used.

Parametersht 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 306 of file rte_fbk_hash.h.

structrte_fbk_hash_table*rte_fbk_hash_find_existing(constchar*name)
Performs a lookup for an existing hash table, and returns a pointer to the table if found.

Parametersname 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.

structrte_fbk_hash_table*rte_fbk_hash_create(conststructrte_fbk_hash_params*params)
Create a new hash table for use with four byte keys.

Parametersparams 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

voidrte_fbk_hash_free(structrte_fbk_hash_table*ht)
Free all memory used by a hash table. Has no effect on hash tables allocated in memory zones

Parametersht Hash table to deallocate.

Macro Definition Documentation

#defineRTE_FBK_HASH_INIT_VAL_DEFAULT0xFFFFFFFF
       Initialising value used when calculating hash.

       Definition at line 32 of file rte_fbk_hash.h.

   #defineRTE_FBK_HASH_ENTRIES_MAX(1<<20)
       The maximum number of entries in the hash table that is supported.

       Definition at line 36 of file rte_fbk_hash.h.

   #defineRTE_FBK_HASH_ENTRIES_PER_BUCKET_MAX256
       The maximum number of entries in each bucket that is supported.

       Definition at line 39 of file rte_fbk_hash.h.

   #defineRTE_FBK_HASH_NAMESIZE32
       Maximum size of string for naming the hash.

       Definition at line 42 of file rte_fbk_hash.h.

Name

       rte_fbk_hash.h

Synopsis

       #include <stdint.h>
       #include <errno.h>
       #include <string.h>
       #include <rte_hash_crc.h>
       #include <rte_jhash.h>

   DataStructures
       struct rte_fbk_hash_params
       union rte_fbk_hash_entry
       struct rte_fbk_hash_tableMacros
       #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

   Typedefstypedef 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)

Typedef Documentation

typedefuint32_t(*rte_fbk_hash_fn)(uint32_tkey,uint32_tinit_val)
       Type of function that can be used for calculating the hash value.

       Definition at line 45 of file rte_fbk_hash.h.