X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_hash%2Frte_hash.h;h=063701173136d70ae341b6c836bbb24547669dff;hb=3f2d6766e3a620a166ee868dfde324e6a1e4b7f3;hp=9e7d9315f2bac044e2af28a8d884cf5866a3a4b4;hpb=8308d2ff5dd7ed0297a548514984f504598d2582;p=dpdk.git diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h index 9e7d9315f2..0637011731 100644 --- a/lib/librte_hash/rte_hash.h +++ b/lib/librte_hash/rte_hash.h @@ -14,6 +14,8 @@ #include #include +#include + #ifdef __cplusplus extern "C" { #endif @@ -37,7 +39,27 @@ extern "C" { /** Flag to support reader writer concurrency */ #define RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY 0x04 -/** Signature of key that is stored internally. */ +/** 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. + */ +#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. + * Currently, extendable bucket table feature is not supported with + * this feature. + */ +#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. */ @@ -119,7 +141,12 @@ void rte_hash_free(struct rte_hash *h); /** - * Reset all hash structure, by zeroing all entries + * 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 */ @@ -137,12 +164,34 @@ rte_hash_reset(struct rte_hash *h); int32_t rte_hash_count(const struct rte_hash *h); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * 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. + */ +__rte_experimental +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. @@ -165,6 +214,11 @@ rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data); * 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. @@ -197,7 +251,9 @@ rte_hash_add_key_with_hash_data(const struct rte_hash *h, const void *key, * - -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. + * 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); @@ -219,7 +275,9 @@ rte_hash_add_key(const struct rte_hash *h, const void *key); * - -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. + * 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); @@ -230,6 +288,14 @@ rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t * 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, + * 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. @@ -251,6 +317,14 @@ rte_hash_del_key(const struct rte_hash *h, const void *key); * 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, + * 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. @@ -289,6 +363,35 @@ int rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position, void **key); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * 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, + * 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. + */ +__rte_experimental +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. @@ -382,7 +485,7 @@ rte_hash_lookup_with_hash(const struct rte_hash *h, /** * Calc a hash value by key. - * This operation is not multi-thread safe. + * This operation is not multi-process safe. * * @param h * Hash table to look in.