summaryrefslogtreecommitdiffstats
path: root/lib/librte_efd/rte_efd.h
diff options
context:
space:
mode:
authorChristian Ehrhardt <christian.ehrhardt@canonical.com>2017-05-16 14:51:32 +0200
committerChristian Ehrhardt <christian.ehrhardt@canonical.com>2017-05-16 16:20:45 +0200
commit7595afa4d30097c1177b69257118d8ad89a539be (patch)
tree4bfeadc905c977e45e54a90c42330553b8942e4e /lib/librte_efd/rte_efd.h
parentce3d555e43e3795b5d9507fcfc76b7a0a92fd0d6 (diff)
Imported Upstream version 17.05
Change-Id: Id1e419c5a214e4a18739663b91f0f9a549f1fdc6 Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Diffstat (limited to 'lib/librte_efd/rte_efd.h')
-rw-r--r--lib/librte_efd/rte_efd.h308
1 files changed, 308 insertions, 0 deletions
diff --git a/lib/librte_efd/rte_efd.h b/lib/librte_efd/rte_efd.h
new file mode 100644
index 00000000..15968635
--- /dev/null
+++ b/lib/librte_efd/rte_efd.h
@@ -0,0 +1,308 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2016-2017 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTE_EFD_H_
+#define _RTE_EFD_H_
+
+/**
+ * @file
+ *
+ * RTE EFD Table
+ */
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*************************************************************************
+ * User selectable constants
+ *************************************************************************/
+
+/*
+ * If possible, best lookup performance will be achieved by ensuring that
+ * the entire table fits in the L3 cache.
+ *
+ * Some formulas for calculating various sizes are listed below:
+ *
+ * # of chunks =
+ * 2 ^ (ceiling(log2((requested # of rules) /
+ * (EFD_CHUNK_NUM_GROUPS * EFD_TARGET_GROUP_NUM_RULES))))
+ *
+ * Target # of rules = (# of chunks) * EFD_CHUNK_NUM_GROUPS *
+ * EFD_TARGET_GROUP_NUM_RULES
+ *
+ * Group Size (in bytes) = 4 (per value bit)
+ *
+ * Table size (in bytes) = RTE_EFD_VALUE_NUM_BITS * (# of chunks) *
+ * EFD_CHUNK_NUM_GROUPS * (group size)
+ */
+
+/**
+ * !!! This parameter should be adjusted for your application !!!
+ *
+ * This parameter adjusts the number of bits of value that can be
+ * stored in the table.
+ * For example, setting the number of bits to 3 will allow storing 8 values
+ * in the table (between 0 and 7).
+ *
+ * This number directly affects the performance of both lookups and insertion.
+ * In general, performance decreases as more bits are stored in the table.
+ *
+ * This number is directly proportional to the size of the online region
+ * used for lookups.
+ *
+ * Note that due to the way the CPU operates on memory, best lookup performance
+ * will be achieved when RTE_EFD_VALUE_NUM_BITS is a multiple of 8.
+ * These values align the hash indexes on 16-byte boundaries.
+ * The greatest performance drop is moving from 8->9 bits, 16->17 bits, etc.
+ *
+ * This value must be between 1 and 32
+ */
+#ifndef RTE_EFD_VALUE_NUM_BITS
+#define RTE_EFD_VALUE_NUM_BITS (8)
+#endif
+
+/*
+ * EFD_TARGET_GROUP_NUM_RULES:
+ * Adjusts how many groups/chunks are allocated at table creation time
+ * to support the requested number of rules. Higher values pack entries
+ * more tightly in memory, resulting in a smaller memory footprint
+ * for the online table.
+ * This comes at the cost of lower insert/update performance.
+ *
+ * EFD_MAX_GROUP_NUM_RULES:
+ * This adjusts the amount of offline memory allocated to store key/value
+ * pairs for the table. The recommended numbers are upper-bounds for
+ * this parameter
+ * - any higher and it becomes very unlikely that a perfect hash function
+ * can be found for that group size. This value should be at
+ * least 40% larger than EFD_TARGET_GROUP_NUM_RULES
+ *
+ * Recommended values for various lookuptable and hashfunc sizes are:
+ *
+ * HASH_FUNC_SIZE = 16, LOOKUPTBL_SIZE = 16:
+ * EFD_TARGET_GROUP_NUM_RULES = 22
+ * EFD_MAX_GROUP_NUM_RULES = 28
+ */
+#define EFD_TARGET_GROUP_NUM_RULES (22)
+#define EFD_MAX_GROUP_NUM_RULES (28LU)
+
+#define EFD_MIN_BALANCED_NUM_RULES 5
+
+/**
+ * Maximum number of keys that can be looked up in one call to efd_lookup_bulk
+ */
+#ifndef RTE_EFD_BURST_MAX
+#define RTE_EFD_BURST_MAX (32)
+#endif
+
+/** Maximum number of characters in efd name.*/
+#define RTE_EFD_NAMESIZE 32
+
+#if (RTE_EFD_VALUE_NUM_BITS > 0 && RTE_EFD_VALUE_NUM_BITS <= 8)
+typedef uint8_t efd_value_t;
+#elif (RTE_EFD_VALUE_NUM_BITS > 8 && RTE_EFD_VALUE_NUM_BITS <= 16)
+typedef uint16_t efd_value_t;
+#elif (RTE_EFD_VALUE_NUM_BITS > 16 && RTE_EFD_VALUE_NUM_BITS <= 32)
+typedef uint32_t efd_value_t;
+#else
+#error("RTE_EFD_VALUE_NUM_BITS must be in the range [1:32]")
+#endif
+
+#define EFD_LOOKUPTBL_SHIFT (32 - 4)
+typedef uint16_t efd_lookuptbl_t;
+typedef uint16_t efd_hashfunc_t;
+
+/**
+ * Creates an EFD table with a single offline region and multiple per-socket
+ * internally-managed copies of the online table used for lookups
+ *
+ * @param name
+ * EFD table name
+ * @param max_num_rules
+ * Minimum number of rules the table should be sized to hold.
+ * Will be rounded up to the next smallest valid table size
+ * @param key_len
+ * Length of the key
+ * @param online_cpu_socket_bitmask
+ * Bitmask specifying which sockets should get a copy of the online table.
+ * LSB = socket 0, etc.
+ * @param offline_cpu_socket
+ * Identifies the socket where the offline table will be allocated
+ * (and most efficiently accessed in the case of updates/insertions)
+ *
+ * @return
+ * EFD table, or NULL if table allocation failed or the bitmask is invalid
+ */
+struct rte_efd_table *
+rte_efd_create(const char *name, uint32_t max_num_rules, uint32_t key_len,
+ uint8_t online_cpu_socket_bitmask, uint8_t offline_cpu_socket);
+
+/**
+ * Releases the resources from an EFD table
+ *
+ * @param table
+ * Table to free
+ */
+void
+rte_efd_free(struct rte_efd_table *table);
+
+/**
+ * Find an existing EFD table object and return a pointer to it.
+ *
+ * @param name
+ * Name of the EFD table as passed to rte_efd_create()
+ * @return
+ * Pointer to EFD 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_efd_table*
+rte_efd_find_existing(const char *name);
+
+#define RTE_EFD_UPDATE_WARN_GROUP_FULL (1)
+#define RTE_EFD_UPDATE_NO_CHANGE (2)
+#define RTE_EFD_UPDATE_FAILED (3)
+
+/**
+ * Computes an updated table entry for the supplied key/value pair.
+ * The update is then immediately applied to the provided table and
+ * all socket-local copies of the chunks are updated.
+ * This operation is not multi-thread safe
+ * and should only be called one from thread.
+ *
+ * @param table
+ * EFD table to reference
+ * @param socket_id
+ * Socket ID to use to lookup existing value (ideally caller's socket id)
+ * @param key
+ * EFD table key to modify
+ * @param value
+ * Value to associate with the key
+ *
+ * @return
+ * RTE_EFD_UPDATE_WARN_GROUP_FULL
+ * Operation is insert, and the last available space in the
+ * key's group was just used
+ * Future inserts may fail as groups fill up
+ * This operation was still successful, and entry contains a valid update
+ * RTE_EFD_UPDATE_FAILED
+ * Either the EFD failed to find a suitable perfect hash or the group was full
+ * This is a fatal error, and the table is now in an indeterminite state
+ * RTE_EFD_UPDATE_NO_CHANGE
+ * Operation resulted in no change to the table (same value already exists)
+ * 0 - success
+ */
+int
+rte_efd_update(struct rte_efd_table *table, unsigned int socket_id,
+ const void *key, efd_value_t value);
+
+/**
+ * Removes any value currently associated with the specified key from the table
+ * This operation is not multi-thread safe
+ * and should only be called from one thread.
+ *
+ * @param table
+ * EFD table to reference
+ * @param socket_id
+ * Socket ID to use to lookup existing value (ideally caller's socket id)
+ * @param key
+ * EFD table key to delete
+ * @param prev_value
+ * If not NULL, will store the previous value here before deleting it
+ *
+ * @return
+ * 0 - successfully found and deleted the key
+ * nonzero otherwise
+ */
+int
+rte_efd_delete(struct rte_efd_table *table, unsigned int socket_id,
+ const void *key, efd_value_t *prev_value);
+
+/**
+ * Looks up the value associated with a key
+ * This operation is multi-thread safe.
+ *
+ * NOTE: Lookups will *always* succeed - this is a property of
+ * using a perfect hash table.
+ * If the specified key was never inserted, a pseudorandom answer will be returned.
+ * There is no way to know based on the lookup if the key was ever inserted
+ * originally, so this must be tracked elsewhere.
+ *
+ * @param table
+ * EFD table to reference
+ * @param socket_id
+ * Socket ID to use to lookup existing value (ideally caller's socket id)
+ * @param key
+ * EFD table key to look up
+ *
+ * @return
+ * Value associated with the key, or random junk if they key was never inserted
+ */
+efd_value_t
+rte_efd_lookup(const struct rte_efd_table *table, unsigned int socket_id,
+ const void *key);
+
+/**
+ * Looks up the value associated with several keys.
+ * This operation is multi-thread safe.
+ *
+ * NOTE: Lookups will *always* succeed - this is a property of
+ * using a perfect hash table.
+ * If the specified key was never inserted, a pseudorandom answer will be returned.
+ * There is no way to know based on the lookup if the key was ever inserted
+ * originally, so this must be tracked elsewhere.
+ *
+ * @param table
+ * EFD table to reference
+ * @param socket_id
+ * Socket ID to use to lookup existing value (ideally caller's socket id)
+ * @param num_keys
+ * Number of keys in the key_list array, must be less than RTE_EFD_BURST_MAX
+ * @param key_list
+ * Array of num_keys pointers which point to keys to look up
+ * @param value_list
+ * Array of size num_keys where lookup values will be stored
+ */
+void
+rte_efd_lookup_bulk(const struct rte_efd_table *table, unsigned int socket_id,
+ int num_keys, const void **key_list,
+ efd_value_t *value_list);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_EFD_H_ */