numam-dpdk/lib/hash/rte_hash.h
Stephen Hemminger e7b1c4665f lib: update documentation of some *_free functions
These functions all behave like libc free() and do
nothing if handed a NULL pointer. The code is already doing
this, this patch just documents the behavior.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
2022-02-12 12:05:01 +01:00

684 lines
22 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2015 Intel Corporation
*/
#ifndef _RTE_HASH_H_
#define _RTE_HASH_H_
/**
* @file
*
* RTE Hash Table
*/
#include <stdint.h>
#include <stddef.h>
#include <rte_compat.h>
#include <rte_rcu_qsbr.h>
#ifdef __cplusplus
extern "C" {
#endif
/** Maximum size of hash table that can be created. */
#define RTE_HASH_ENTRIES_MAX (1 << 30)
/** Maximum number of characters in hash name.*/
#define RTE_HASH_NAMESIZE 32
/** Maximum number of keys that can be searched for using rte_hash_lookup_bulk. */
#define RTE_HASH_LOOKUP_BULK_MAX 64
#define RTE_HASH_LOOKUP_MULTI_MAX RTE_HASH_LOOKUP_BULK_MAX
/** Enable Hardware transactional memory support. */
#define RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT 0x01
/** Default behavior of insertion, single writer/multi writer */
#define RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD 0x02
/** Flag to support reader writer concurrency */
#define RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY 0x04
/** Flag to indicate the extendable bucket table feature should be used */
#define RTE_HASH_EXTRA_FLAGS_EXT_TABLE 0x08
/** Flag to disable freeing of key index on hash delete.
* Refer to rte_hash_del_xxx APIs for more details.
* This is enabled by default when RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF
* is enabled. However, if internal RCU is enabled, freeing of internal
* memory/index is done on delete
*/
#define RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL 0x10
/** Flag to support lock free reader writer concurrency. Both single writer
* and multi writer use cases are supported.
*/
#define RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF 0x20
/**
* The type of hash value of a key.
* It should be a value of at least 32bit with fully random pattern.
*/
typedef uint32_t hash_sig_t;
/** Type of function that can be used for calculating the hash value. */
typedef uint32_t (*rte_hash_function)(const void *key, uint32_t key_len,
uint32_t init_val);
/** Type of function used to compare the hash key. */
typedef int (*rte_hash_cmp_eq_t)(const void *key1, const void *key2, size_t key_len);
/**
* Type of function used to free data stored in the key.
* Required when using internal RCU to allow application to free key-data once
* the key is returned to the ring of free key-slots.
*/
typedef void (*rte_hash_free_key_data)(void *p, void *key_data);
/**
* Parameters used when creating the hash table.
*/
struct rte_hash_parameters {
const char *name; /**< Name of the hash. */
uint32_t entries; /**< Total hash table entries. */
uint32_t reserved; /**< Unused field. Should be set to 0 */
uint32_t key_len; /**< Length of hash key. */
rte_hash_function hash_func; /**< Primary Hash function used to calculate hash. */
uint32_t hash_func_init_val; /**< Init value used by hash_func. */
int socket_id; /**< NUMA Socket ID for memory. */
uint8_t extra_flag; /**< Indicate if additional parameters are present. */
};
/** RCU reclamation modes */
enum rte_hash_qsbr_mode {
/** Create defer queue for reclaim. */
RTE_HASH_QSBR_MODE_DQ = 0,
/** Use blocking mode reclaim. No defer queue created. */
RTE_HASH_QSBR_MODE_SYNC
};
/** HASH RCU QSBR configuration structure. */
struct rte_hash_rcu_config {
struct rte_rcu_qsbr *v; /**< RCU QSBR variable. */
enum rte_hash_qsbr_mode mode;
/**< Mode of RCU QSBR. RTE_HASH_QSBR_MODE_xxx
* '0' for default: create defer queue for reclaim.
*/
uint32_t dq_size;
/**< RCU defer queue size.
* default: total hash table entries.
*/
uint32_t trigger_reclaim_limit; /**< Threshold to trigger auto reclaim. */
uint32_t max_reclaim_size;
/**< Max entries to reclaim in one go.
* default: RTE_HASH_RCU_DQ_RECLAIM_MAX.
*/
void *key_data_ptr;
/**< Pointer passed to the free function. Typically, this is the
* pointer to the data structure to which the resource to free
* (key-data) belongs. This can be NULL.
*/
rte_hash_free_key_data free_key_data_func;
/**< Function to call to free the resource (key-data). */
};
/** @internal A hash table structure. */
struct rte_hash;
/**
* Create a new hash table.
*
* @param params
* Parameters used to create and initialise the hash table.
* @return
* Pointer to hash table structure that is used in future hash table
* operations, or NULL on error, with error code set in rte_errno.
* Possible rte_errno errors 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
* - ENOENT - missing entry
* - EINVAL - invalid parameter 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
*/
struct rte_hash *
rte_hash_create(const struct rte_hash_parameters *params);
/**
* Set a new hash compare function other than the default one.
*
* @note Function pointer does not work with multi-process, so do not use it
* in multi-process mode.
*
* @param h
* Hash table for which the function is to be changed
* @param func
* New compare function
*/
void rte_hash_set_cmp_func(struct rte_hash *h, rte_hash_cmp_eq_t func);
/**
* Find an existing hash table object and return a pointer to it.
*
* @param name
* Name of the hash table as passed to rte_hash_create()
* @return
* Pointer to hash table or NULL if object not found
* with rte_errno set appropriately. Possible rte_errno values include:
* - ENOENT - value not available for return
*/
struct rte_hash *
rte_hash_find_existing(const char *name);
/**
* De-allocate all memory used by hash table.
*
* @param h
* Hash table to free, if NULL, the function does nothing.
*
*/
void
rte_hash_free(struct rte_hash *h);
/**
* Reset all hash structure, by zeroing all entries.
* When RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF is enabled,
* it is application's responsibility to make sure that
* none of the readers are referencing the hash table
* while calling this API.
*
* @param h
* Hash table to reset
*/
void
rte_hash_reset(struct rte_hash *h);
/**
* Return the number of keys in the hash table
* @param h
* Hash table to query from
* @return
* - -EINVAL if parameters are invalid
* - A value indicating how many keys were inserted in the table.
*/
int32_t
rte_hash_count(const struct rte_hash *h);
/**
* Return the maximum key value ID that could possibly be returned by
* rte_hash_add_key function.
*
* @param h
* Hash table to query from
* @return
* - -EINVAL if parameters are invalid
* - A value indicating the max key ID of key slots present in the table.
*/
int32_t
rte_hash_max_key_id(const struct rte_hash *h);
/**
* Add a key-value pair to an existing hash table.
* This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
* If the key exists already in the table, this API updates its value
* with 'data' passed in this API. It is the responsibility of
* the application to manage any memory associated with the old value.
* The readers might still be using the old value even after this API
* has returned.
*
* @param h
* Hash table to add the key to.
* @param key
* Key to add to the hash table.
* @param data
* Data to add to the hash table.
* @return
* - 0 if added successfully
* - -EINVAL if the parameters are invalid.
* - -ENOSPC if there is no space in the hash for this key.
*/
int
rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data);
/**
* Add a key-value pair with a pre-computed hash value
* to an existing hash table.
* This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
* If the key exists already in the table, this API updates its value
* with 'data' passed in this API. It is the responsibility of
* the application to manage any memory associated with the old value.
* The readers might still be using the old value even after this API
* has returned.
*
* @param h
* Hash table to add the key to.
* @param key
* Key to add to the hash table.
* @param sig
* Precomputed hash value for 'key'
* @param data
* Data to add to the hash table.
* @return
* - 0 if added successfully
* - -EINVAL if the parameters are invalid.
* - -ENOSPC if there is no space in the hash for this key.
*/
int32_t
rte_hash_add_key_with_hash_data(const struct rte_hash *h, const void *key,
hash_sig_t sig, void *data);
/**
* Add a key to an existing hash table. This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to add the key to.
* @param key
* Key to add to the hash table.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOSPC if there is no space in the hash for this key.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key. This
* unique key id may be larger than the user specified entry count
* when RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD flag is set.
*/
int32_t
rte_hash_add_key(const struct rte_hash *h, const void *key);
/**
* Add a key to an existing hash table.
* This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to add the key to.
* @param key
* Key to add to the hash table.
* @param sig
* Precomputed hash value for 'key'.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOSPC if there is no space in the hash for this key.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key. This
* unique key ID may be larger than the user specified entry count
* when RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD flag is set.
*/
int32_t
rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t sig);
/**
* Remove a key from an existing hash table.
* This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
* If RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL or
* RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF is enabled and
* internal RCU is NOT enabled,
* the key index returned by rte_hash_add_key_xxx APIs will not be
* freed by this API. rte_hash_free_key_with_position API must be called
* additionally to free the index associated with the key.
* rte_hash_free_key_with_position API should be called after all
* the readers have stopped referencing the entry corresponding to
* this key. RCU mechanisms could be used to determine such a state.
*
* @param h
* Hash table to remove the key from.
* @param key
* Key to remove from the hash table.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
*/
int32_t
rte_hash_del_key(const struct rte_hash *h, const void *key);
/**
* Remove a key from an existing hash table.
* This operation is not multi-thread safe
* and should only be called from one thread by default.
* Thread safety can be enabled by setting flag during
* table creation.
* If RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL or
* RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF is enabled and
* internal RCU is NOT enabled,
* the key index returned by rte_hash_add_key_xxx APIs will not be
* freed by this API. rte_hash_free_key_with_position API must be called
* additionally to free the index associated with the key.
* rte_hash_free_key_with_position API should be called after all
* the readers have stopped referencing the entry corresponding to
* this key. RCU mechanisms could be used to determine such a state.
*
* @param h
* Hash table to remove the key from.
* @param key
* Key to remove from the hash table.
* @param sig
* Precomputed hash value for 'key'.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
*/
int32_t
rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t sig);
/**
* Find a key in the hash table given the position.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to get the key from.
* @param position
* Position returned when the key was inserted.
* @param key
* Output containing a pointer to the key
* @return
* - 0 if retrieved successfully
* - -EINVAL if the parameters are invalid.
* - -ENOENT if no valid key is found in the given position.
*/
int
rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position,
void **key);
/**
* Free a hash key in the hash table given the position
* of the key. This operation is not multi-thread safe and should
* only be called from one thread by default. Thread safety
* can be enabled by setting flag during table creation.
* If RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL or
* RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF is enabled and
* internal RCU is NOT enabled,
* the key index returned by rte_hash_del_key_xxx APIs must be freed
* using this API. This API should be called after all the readers
* have stopped referencing the entry corresponding to this key.
* RCU mechanisms could be used to determine such a state.
* This API does not validate if the key is already freed.
*
* @param h
* Hash table to free the key from.
* @param position
* Position returned when the key was deleted.
* @return
* - 0 if freed successfully
* - -EINVAL if the parameters are invalid.
*/
int
rte_hash_free_key_with_position(const struct rte_hash *h,
const int32_t position);
/**
* Find a key-value pair in the hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param key
* Key to find.
* @param data
* Output with pointer to data returned from the hash table.
* @return
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
*/
int
rte_hash_lookup_data(const struct rte_hash *h, const void *key, void **data);
/**
* Find a key-value pair with a pre-computed hash value
* to an existing hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param key
* Key to find.
* @param sig
* Precomputed hash value for 'key'
* @param data
* Output with pointer to data returned from the hash table.
* @return
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
*/
int
rte_hash_lookup_with_hash_data(const struct rte_hash *h, const void *key,
hash_sig_t sig, void **data);
/**
* Find a key in the hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param key
* Key to find.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
*/
int32_t
rte_hash_lookup(const struct rte_hash *h, const void *key);
/**
* Find a key in the hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param key
* Key to find.
* @param sig
* Precomputed hash value for 'key'.
* @return
* - -EINVAL if the parameters are invalid.
* - -ENOENT if the key is not found.
* - A positive value that can be used by the caller as an offset into an
* array of user data. This value is unique for this key, and is the same
* value that was returned when the key was added.
*/
int32_t
rte_hash_lookup_with_hash(const struct rte_hash *h,
const void *key, hash_sig_t sig);
/**
* Calc a hash value by key.
* This operation is not multi-process safe.
*
* @param h
* Hash table to look in.
* @param key
* Key to find.
* @return
* - hash value
*/
hash_sig_t
rte_hash_hash(const struct rte_hash *h, const void *key);
/**
* Find multiple keys in the hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param keys
* A pointer to a list of keys to look for.
* @param num_keys
* How many keys are in the keys list (less than RTE_HASH_LOOKUP_BULK_MAX).
* @param hit_mask
* Output containing a bitmask with all successful lookups.
* @param data
* Output containing array of data returned from all the successful lookups.
* @return
* -EINVAL if there's an error, otherwise number of successful lookups.
*/
int
rte_hash_lookup_bulk_data(const struct rte_hash *h, const void **keys,
uint32_t num_keys, uint64_t *hit_mask, void *data[]);
/**
* Find multiple keys in the hash table with precomputed hash value array.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param keys
* A pointer to a list of keys to look for.
* @param sig
* A pointer to a list of precomputed hash values for keys.
* @param num_keys
* How many keys are in the keys list (less than RTE_HASH_LOOKUP_BULK_MAX).
* @param positions
* Output containing a list of values, corresponding to the list of keys that
* can be used by the caller as an offset into an array of user data. These
* values are unique for each key, and are the same values that were returned
* when each key was added. If a key in the list was not found, then -ENOENT
* will be the value.
* @return
* -EINVAL if there's an error, otherwise 0.
*/
int
rte_hash_lookup_with_hash_bulk(const struct rte_hash *h, const void **keys,
hash_sig_t *sig, uint32_t num_keys, int32_t *positions);
/**
* Find multiple keys in the hash table with precomputed hash value array.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param keys
* A pointer to a list of keys to look for.
* @param sig
* A pointer to a list of precomputed hash values for keys.
* @param num_keys
* How many keys are in the keys list (less than RTE_HASH_LOOKUP_BULK_MAX).
* @param hit_mask
* Output containing a bitmask with all successful lookups.
* @param data
* Output containing array of data returned from all the successful lookups.
* @return
* -EINVAL if there's an error, otherwise number of successful lookups.
*/
int
rte_hash_lookup_with_hash_bulk_data(const struct rte_hash *h,
const void **keys, hash_sig_t *sig,
uint32_t num_keys, uint64_t *hit_mask, void *data[]);
/**
* Find multiple keys in the hash table.
* This operation is multi-thread safe with regarding to other lookup threads.
* Read-write concurrency can be enabled by setting flag during
* table creation.
*
* @param h
* Hash table to look in.
* @param keys
* A pointer to a list of keys to look for.
* @param num_keys
* How many keys are in the keys list (less than RTE_HASH_LOOKUP_BULK_MAX).
* @param positions
* Output containing a list of values, corresponding to the list of keys that
* can be used by the caller as an offset into an array of user data. These
* values are unique for each key, and are the same values that were returned
* when each key was added. If a key in the list was not found, then -ENOENT
* will be the value.
* @return
* -EINVAL if there's an error, otherwise 0.
*/
int
rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
uint32_t num_keys, int32_t *positions);
/**
* Iterate through the hash table, returning key-value pairs.
*
* @param h
* Hash table to iterate
* @param key
* Output containing the key where current iterator
* was pointing at
* @param data
* Output containing the data associated with key.
* Returns NULL if data was not stored.
* @param next
* Pointer to iterator. Should be 0 to start iterating the hash table.
* Iterator is incremented after each call of this function.
* @return
* Position where key was stored, if successful.
* - -EINVAL if the parameters are invalid.
* - -ENOENT if end of the hash table.
*/
int32_t
rte_hash_iterate(const struct rte_hash *h, const void **key, void **data, uint32_t *next);
/**
* Associate RCU QSBR variable with a Hash object.
* This API should be called to enable the integrated RCU QSBR support and
* should be called immediately after creating the Hash object.
*
* @param h
* the hash object to add RCU QSBR
* @param cfg
* RCU QSBR configuration
* @return
* On success - 0
* On error - 1 with error code set in rte_errno.
* Possible rte_errno codes are:
* - EINVAL - invalid pointer
* - EEXIST - already added QSBR
* - ENOMEM - memory allocation failure
*/
int rte_hash_rcu_qsbr_add(struct rte_hash *h, struct rte_hash_rcu_config *cfg);
#ifdef __cplusplus
}
#endif
#endif /* _RTE_HASH_H_ */