numam-dpdk/lib/librte_table/rte_lru.h
Cristian Dumitrescu 8aa327214c table: hash
Various types of hash tables presented under the Packet Framework toolbox.

Hash table types:
1. Extendible bucket (ext): when bucket is full, bucket is extended with
   more keys
2. Least Recently Used (LRU): when bucket is full, the LRU entry is discarded
3. Pre-computed key signature: RX core extracts the key n-tuple from the
   packet, computes the key signature and saves the key and key signature
   within the packet meta-data; flow classification core performs the actual
   lookup (the bucket search stage) after reading the key and key signature
   from packet meta-data
4. Signature computed on-the-fly (do-sig version): the same CPU core extracts
   the key n-tuple from pkt, computes key signature and performs the table
   lookup
5. Configurable key size or optimized for single key size (8-byte, 16-byte
   and 32-byte key sizes)

Signed-off-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>
Acked-by: Pablo de Lara Guarch <pablo.de.lara.guarch@intel.com>
Acked by: Ivan Boule <ivan.boule@6wind.com>
2014-06-17 03:34:10 +02:00

214 lines
6.3 KiB
C

/*-
* BSD LICENSE
*
* Copyright(c) 2010-2014 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 __INCLUDE_RTE_LRU_H__
#define __INCLUDE_RTE_LRU_H__
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
#ifdef __INTEL_COMPILER
#define GCC_VERSION (0)
#else
#define GCC_VERSION (__GNUC__ * 10000+__GNUC_MINOR__*100 + __GNUC_PATCHLEVEL__)
#endif
#ifndef RTE_TABLE_HASH_LRU_STRATEGY
#ifdef __SSE4_2__
#define RTE_TABLE_HASH_LRU_STRATEGY 2
#else /* if no SSE, use simple scalar version */
#define RTE_TABLE_HASH_LRU_STRATEGY 1
#endif
#endif
#ifndef RTE_ARCH_X86_64
#undef RTE_TABLE_HASH_LRU_STRATEGY
#define RTE_TABLE_HASH_LRU_STRATEGY 1
#endif
#if (RTE_TABLE_HASH_LRU_STRATEGY < 0) || (RTE_TABLE_HASH_LRU_STRATEGY > 3)
#error Invalid value for RTE_TABLE_HASH_LRU_STRATEGY
#endif
#if RTE_TABLE_HASH_LRU_STRATEGY == 0
#define lru_init(bucket) \
do \
bucket = bucket; \
while (0)
#define lru_pos(bucket) (bucket->lru_list & 0xFFFFLLU)
#define lru_update(bucket, mru_val) \
do { \
bucket = bucket; \
mru_val = mru_val; \
} while (0)
#elif RTE_TABLE_HASH_LRU_STRATEGY == 1
#define lru_init(bucket) \
do \
bucket->lru_list = 0x0000000100020003LLU; \
while (0)
#define lru_pos(bucket) (bucket->lru_list & 0xFFFFLLU)
#define lru_update(bucket, mru_val) \
do { \
uint64_t x, pos, x0, x1, x2, mask; \
\
x = bucket->lru_list; \
\
pos = 4; \
if ((x >> 48) == ((uint64_t) mru_val)) \
pos = 3; \
\
if (((x >> 32) & 0xFFFFLLU) == ((uint64_t) mru_val)) \
pos = 2; \
\
if (((x >> 16) & 0xFFFFLLU) == ((uint64_t) mru_val)) \
pos = 1; \
\
if ((x & 0xFFFFLLU) == ((uint64_t) mru_val)) \
pos = 0; \
\
\
pos <<= 4; \
mask = (~0LLU) << pos; \
x0 = x & (~mask); \
x1 = (x >> 16) & mask; \
x2 = (x << (48 - pos)) & (0xFFFFLLU << 48); \
x = x0 | x1 | x2; \
\
if (pos != 64) \
bucket->lru_list = x; \
} while (0)
#elif RTE_TABLE_HASH_LRU_STRATEGY == 2
#if GCC_VERSION > 40306
#include <x86intrin.h>
#else
#include <emmintrin.h>
#include <smmintrin.h>
#include <xmmintrin.h>
#endif
#define lru_init(bucket) \
do \
bucket->lru_list = 0x0000000100020003LLU; \
while (0)
#define lru_pos(bucket) (bucket->lru_list & 0xFFFFLLU)
#define lru_update(bucket, mru_val) \
do { \
/* set up the masks for all possible shuffles, depends on pos */\
static uint64_t masks[10] = { \
/* Shuffle order; Make Zero (see _mm_shuffle_epi8 manual) */\
0x0100070605040302, 0x8080808080808080, \
0x0302070605040100, 0x8080808080808080, \
0x0504070603020100, 0x8080808080808080, \
0x0706050403020100, 0x8080808080808080, \
0x0706050403020100, 0x8080808080808080}; \
/* load up one register with repeats of mru-val */ \
uint64_t mru2 = mru_val; \
uint64_t mru3 = mru2 | (mru2 << 16); \
uint64_t lru = bucket->lru_list; \
/* XOR to cause the word we're looking for to go to zero */ \
uint64_t mru = lru ^ ((mru3 << 32) | mru3); \
__m128i c = _mm_cvtsi64_si128(mru); \
__m128i b = _mm_cvtsi64_si128(lru); \
/* Find the minimum value (first zero word, if it's in there) */\
__m128i d = _mm_minpos_epu16(c); \
/* Second word is the index to found word (first word is the value) */\
unsigned pos = _mm_extract_epi16(d, 1); \
/* move the recently used location to top of list */ \
__m128i k = _mm_shuffle_epi8(b, *((__m128i *) &masks[2 * pos]));\
/* Finally, update the original list with the reordered data */ \
bucket->lru_list = _mm_extract_epi64(k, 0); \
/* Phwew! */ \
} while (0)
#elif RTE_TABLE_HASH_LRU_STRATEGY == 3
#if GCC_VERSION > 40306
#include <x86intrin.h>
#else
#include <emmintrin.h>
#include <smmintrin.h>
#include <xmmintrin.h>
#endif
#define lru_init(bucket) \
do \
bucket->lru_list = ~0LLU; \
while (0)
static inline int
f_lru_pos(uint64_t lru_list)
{
__m128i lst = _mm_set_epi64x((uint64_t)-1, lru_list);
__m128i min = _mm_minpos_epu16(lst);
return _mm_extract_epi16(min, 1);
}
#define lru_pos(bucket) f_lru_pos(bucket->lru_list)
#define lru_update(bucket, mru_val) \
do { \
const uint64_t orvals[] = {0xFFFFLLU, 0xFFFFLLU << 16, \
0xFFFFLLU << 32, 0xFFFFLLU << 48, 0LLU}; \
const uint64_t decs[] = {0x1000100010001LLU, 0}; \
__m128i lru = _mm_cvtsi64_si128(bucket->lru_list); \
__m128i vdec = _mm_cvtsi64_si128(decs[mru_val>>2]); \
lru = _mm_subs_epu16(lru, vdec); \
bucket->lru_list = _mm_extract_epi64(lru, 0) | orvals[mru_val]; \
} while (0)
#else
#error "Incorrect value for RTE_TABLE_HASH_LRU_STRATEGY"
#endif
#ifdef __cplusplus
}
#endif
#endif