New upstream version 18.08

[deb_dpdk.git] / lib / librte_hash / rte_hash.h

diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h
index 3beaca7..9e7d931 100644 (file)
--- a/lib/librte_hash/rte_hash.h
+++ b/lib/librte_hash/rte_hash.h
@@ -34,6 +34,9 @@ extern "C" {
 /** 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
+
 /** Signature of key that is stored internally. */
 typedef uint32_t hash_sig_t;
 
@@ -123,10 +126,23 @@ rte_hash_free(struct rte_hash *h);
 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);
+
 /**
  * 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.
+ * 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.
@@ -146,7 +162,9 @@ 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.
+ * 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.
@@ -167,7 +185,9 @@ rte_hash_add_key_with_hash_data(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.
+ * 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.
@@ -185,7 +205,9 @@ 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.
+ * 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.
@@ -205,7 +227,9 @@ rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t
 /**
  * Remove a key from an existing hash table.
  * This operation is not multi-thread safe
- * and should only be called from one thread.
+ * 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 remove the key from.
@@ -224,7 +248,9 @@ 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.
+ * 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 remove the key from.
@@ -244,7 +270,9 @@ rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t
 
 /**
  * Find a key in the hash table given the position.
- * This operation is multi-thread safe.
+ * 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.
@@ -254,8 +282,8 @@ rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key, hash_sig_t
  *   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.
+ *   - -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,
@@ -263,7 +291,9 @@ rte_hash_get_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.
+ * 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.
@@ -272,9 +302,11 @@ rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position,
  * @param data
  *   Output with pointer to data returned from the hash table.
  * @return
- *   0 if successful lookup
- *   - 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.
+ *   - -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);
@@ -282,7 +314,9 @@ 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.
+ * 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.
@@ -293,9 +327,11 @@ rte_hash_lookup_data(const struct rte_hash *h, const void *key, void **data);
  * @param data
  *   Output with pointer to data returned from the hash table.
  * @return
- *   0 if successful lookup
- *   - 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.
+ *   - -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,
@@ -303,7 +339,9 @@ rte_hash_lookup_with_hash_data(const struct rte_hash *h, const void *key,
 
 /**
  * Find a key in the hash table.
- * This operation is multi-thread safe.
+ * 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.
@@ -321,14 +359,16 @@ rte_hash_lookup(const struct rte_hash *h, const void *key);
 
 /**
  * Find a key in the hash table.
- * This operation is multi-thread safe.
+ * 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
- *   Hash value to remove from the hash table.
+ *   Precomputed hash value for 'key'.
  * @return
  *   - -EINVAL if the parameters are invalid.
  *   - -ENOENT if the key is not found.
@@ -356,7 +396,9 @@ rte_hash_hash(const struct rte_hash *h, const void *key);
 
 /**
  * Find multiple keys in the hash table.
- * This operation is multi-thread safe.
+ * 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.
@@ -377,7 +419,9 @@ rte_hash_lookup_bulk_data(const struct rte_hash *h, const void **keys,
 
 /**
  * Find multiple keys in the hash table.
- * This operation is multi-thread safe.
+ * 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.