X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_hash%2Frte_jhash.h;h=207478c2823dd703593aaf11271e4f5f0b174946;hb=748eccb97cdc8af80b026a9f4d910a4c0f1b862b;hp=8572c6c88bc424ce3f2a24b1ed2813a601add010;hpb=1c1d4d7a923d4804f1926fc5264f9ecdd8977b04;p=dpdk.git diff --git a/lib/librte_hash/rte_jhash.h b/lib/librte_hash/rte_jhash.h index 8572c6c88b..207478c282 100644 --- a/lib/librte_hash/rte_jhash.h +++ b/lib/librte_hash/rte_jhash.h @@ -1,13 +1,13 @@ /*- * BSD LICENSE - * - * Copyright(c) 2010-2013 Intel Corporation. All rights reserved. + * + * Copyright(c) 2010-2015 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 @@ -17,7 +17,7 @@ * * 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 @@ -45,38 +45,247 @@ extern "C" { #endif #include +#include +#include + +#include +#include /* jhash.h: Jenkins hash support. * - * Copyright (C) 1996 Bob Jenkins (bob_jenkins@burtleburtle.net) + * Copyright (C) 2006 Bob Jenkins (bob_jenkins@burtleburtle.net) * * http://burtleburtle.net/bob/hash/ * * These are the credits from Bob's sources: * - * lookup2.c, by Bob Jenkins, December 1996, Public Domain. - * hash(), hash2(), hash3, and mix() are externally useful functions. - * Routines to test the hash are included if SELF_TEST is defined. - * You can use this free for any purpose. It has no warranty. + * lookup3.c, by Bob Jenkins, May 2006, Public Domain. + * + * These are functions for producing 32-bit hashes for hash table lookup. + * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final() + * are externally useful functions. Routines to test the hash are included + * if SELF_TEST is defined. You can use this free for any purpose. It's in + * the public domain. It has no warranty. * * $FreeBSD$ */ +#define rot(x, k) (((x) << (k)) | ((x) >> (32-(k)))) + /** @internal Internal function. NOTE: Arguments are modified. */ #define __rte_jhash_mix(a, b, c) do { \ - a -= b; a -= c; a ^= (c>>13); \ - b -= c; b -= a; b ^= (a<<8); \ - c -= a; c -= b; c ^= (b>>13); \ - a -= b; a -= c; a ^= (c>>12); \ - b -= c; b -= a; b ^= (a<<16); \ - c -= a; c -= b; c ^= (b>>5); \ - a -= b; a -= c; a ^= (c>>3); \ - b -= c; b -= a; b ^= (a<<10); \ - c -= a; c -= b; c ^= (b>>15); \ + a -= c; a ^= rot(c, 4); c += b; \ + b -= a; b ^= rot(a, 6); a += c; \ + c -= b; c ^= rot(b, 8); b += a; \ + a -= c; a ^= rot(c, 16); c += b; \ + b -= a; b ^= rot(a, 19); a += c; \ + c -= b; c ^= rot(b, 4); b += a; \ +} while (0) + +#define __rte_jhash_final(a, b, c) do { \ + c ^= b; c -= rot(b, 14); \ + a ^= c; a -= rot(c, 11); \ + b ^= a; b -= rot(a, 25); \ + c ^= b; c -= rot(b, 16); \ + a ^= c; a -= rot(c, 4); \ + b ^= a; b -= rot(a, 14); \ + c ^= b; c -= rot(b, 24); \ } while (0) /** The golden ratio: an arbitrary value. */ -#define RTE_JHASH_GOLDEN_RATIO 0x9e3779b9 +#define RTE_JHASH_GOLDEN_RATIO 0xdeadbeef + +#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN +#define BIT_SHIFT(x, y, k) (((x) >> (k)) | ((uint64_t)(y) << (32-(k)))) +#else +#define BIT_SHIFT(x, y, k) (((uint64_t)(x) << (k)) | ((y) >> (32-(k)))) +#endif + +#define LOWER8b_MASK rte_le_to_cpu_32(0xff) +#define LOWER16b_MASK rte_le_to_cpu_32(0xffff) +#define LOWER24b_MASK rte_le_to_cpu_32(0xffffff) + +static inline void +__rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, + uint32_t *pb, unsigned check_align) +{ + uint32_t a, b, c; + + /* Set up the internal state */ + a = b = c = RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + *pc; + c += *pb; + + /* + * Check key alignment. For x86 architecture, first case is always optimal + * If check_align is not set, first case will be used + */ +#if defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_I686) || defined(RTE_ARCH_X86_X32) + const uint32_t *k = (const uint32_t *)key; + const uint32_t s = 0; +#else + const uint32_t *k = (uint32_t *)((uintptr_t)key & (uintptr_t)~3); + const uint32_t s = ((uintptr_t)key & 3) * CHAR_BIT; +#endif + if (!check_align || s == 0) { + while (length > 12) { + a += k[0]; + b += k[1]; + c += k[2]; + + __rte_jhash_mix(a, b, c); + + k += 3; + length -= 12; + } + + switch (length) { + case 12: + c += k[2]; b += k[1]; a += k[0]; break; + case 11: + c += k[2] & LOWER24b_MASK; b += k[1]; a += k[0]; break; + case 10: + c += k[2] & LOWER16b_MASK; b += k[1]; a += k[0]; break; + case 9: + c += k[2] & LOWER8b_MASK; b += k[1]; a += k[0]; break; + case 8: + b += k[1]; a += k[0]; break; + case 7: + b += k[1] & LOWER24b_MASK; a += k[0]; break; + case 6: + b += k[1] & LOWER16b_MASK; a += k[0]; break; + case 5: + b += k[1] & LOWER8b_MASK; a += k[0]; break; + case 4: + a += k[0]; break; + case 3: + a += k[0] & LOWER24b_MASK; break; + case 2: + a += k[0] & LOWER16b_MASK; break; + case 1: + a += k[0] & LOWER8b_MASK; break; + /* zero length strings require no mixing */ + case 0: + *pc = c; + *pb = b; + return; + }; + } else { + /* all but the last block: affect some 32 bits of (a, b, c) */ + while (length > 12) { + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + c += BIT_SHIFT(k[2], k[3], s); + __rte_jhash_mix(a, b, c); + + k += 3; + length -= 12; + } + + /* last block: affect all 32 bits of (c) */ + switch (length) { + case 12: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + c += BIT_SHIFT(k[2], k[3], s); + break; + case 11: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + c += BIT_SHIFT(k[2], k[3], s) & LOWER24b_MASK; + break; + case 10: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + c += BIT_SHIFT(k[2], k[3], s) & LOWER16b_MASK; + break; + case 9: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + c += BIT_SHIFT(k[2], k[3], s) & LOWER8b_MASK; + break; + case 8: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s); + break; + case 7: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s) & LOWER24b_MASK; + break; + case 6: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s) & LOWER16b_MASK; + break; + case 5: + a += BIT_SHIFT(k[0], k[1], s); + b += BIT_SHIFT(k[1], k[2], s) & LOWER8b_MASK; + break; + case 4: + a += BIT_SHIFT(k[0], k[1], s); + break; + case 3: + a += BIT_SHIFT(k[0], k[1], s) & LOWER24b_MASK; + break; + case 2: + a += BIT_SHIFT(k[0], k[1], s) & LOWER16b_MASK; + break; + case 1: + a += BIT_SHIFT(k[0], k[1], s) & LOWER8b_MASK; + break; + /* zero length strings require no mixing */ + case 0: + *pc = c; + *pb = b; + return; + } + } + + __rte_jhash_final(a, b, c); + + *pc = c; + *pb = b; +} + +/** + * Same as rte_jhash, but takes two seeds and return two uint32_ts. + * pc and pb must be non-null, and *pc and *pb must both be initialized + * with seeds. If you pass in (*pb)=0, the output (*pc) will be + * the same as the return value from rte_jhash. + * + * @param key + * Key to calculate hash of. + * @param length + * Length of key in bytes. + * @param pc + * IN: seed OUT: primary hash value. + * @param pb + * IN: second seed OUT: secondary hash value. + */ +static inline void +rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, uint32_t *pb) +{ + __rte_jhash_2hashes(key, length, pc, pb, 1); +} + +/** + * Same as rte_jhash_32b, but takes two seeds and return two uint32_ts. + * pc and pb must be non-null, and *pc and *pb must both be initialized + * with seeds. If you pass in (*pb)=0, the output (*pc) will be + * the same as the return value from rte_jhash_32b. + * + * @param k + * Key to calculate hash of. + * @param length + * Length of key in units of 4 bytes. + * @param pc + * IN: seed OUT: primary hash value. + * @param pb + * IN: second seed OUT: secondary hash value. + */ +static inline void +rte_jhash_32b_2hashes(const uint32_t *k, uint32_t length, uint32_t *pc, uint32_t *pb) +{ + __rte_jhash_2hashes((const void *) k, (length << 2), pc, pb, 0); +} /** * The most generic version, hashes an arbitrary sequence @@ -95,44 +304,11 @@ extern "C" { static inline uint32_t rte_jhash(const void *key, uint32_t length, uint32_t initval) { - uint32_t a, b, c, len; - const uint8_t *k = (const uint8_t *)key; - const uint32_t *k32 = (const uint32_t *)key; - - len = length; - a = b = RTE_JHASH_GOLDEN_RATIO; - c = initval; + uint32_t initval2 = 0; - while (len >= 12) { - a += k32[0]; - b += k32[1]; - c += k32[2]; + rte_jhash_2hashes(key, length, &initval, &initval2); - __rte_jhash_mix(a,b,c); - - k += (3 * sizeof(uint32_t)), k32 += 3; - len -= (3 * sizeof(uint32_t)); - } - - c += length; - switch (len) { - case 11: c += ((uint32_t)k[10] << 24); - case 10: c += ((uint32_t)k[9] << 16); - case 9 : c += ((uint32_t)k[8] << 8); - case 8 : b += ((uint32_t)k[7] << 24); - case 7 : b += ((uint32_t)k[6] << 16); - case 6 : b += ((uint32_t)k[5] << 8); - case 5 : b += k[4]; - case 4 : a += ((uint32_t)k[3] << 24); - case 3 : a += ((uint32_t)k[2] << 16); - case 2 : a += ((uint32_t)k[1] << 8); - case 1 : a += k[0]; - default: break; - }; - - __rte_jhash_mix(a,b,c); - - return c; + return initval; } /** @@ -149,46 +325,37 @@ rte_jhash(const void *key, uint32_t length, uint32_t initval) * Calculated hash value. */ static inline uint32_t -rte_jhash2(uint32_t *k, uint32_t length, uint32_t initval) +rte_jhash_32b(const uint32_t *k, uint32_t length, uint32_t initval) { - uint32_t a, b, c, len; - - a = b = RTE_JHASH_GOLDEN_RATIO; - c = initval; - len = length; - - while (len >= 3) { - a += k[0]; - b += k[1]; - c += k[2]; - __rte_jhash_mix(a, b, c); - k += 3; len -= 3; - } + uint32_t initval2 = 0; - c += length * 4; + rte_jhash_32b_2hashes(k, length, &initval, &initval2); + + return initval; +} - switch (len) { - case 2 : b += k[1]; - case 1 : a += k[0]; - default: break; - }; +static inline uint32_t +__rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval) +{ + a += RTE_JHASH_GOLDEN_RATIO + initval; + b += RTE_JHASH_GOLDEN_RATIO + initval; + c += RTE_JHASH_GOLDEN_RATIO + initval; - __rte_jhash_mix(a,b,c); + __rte_jhash_final(a, b, c); return c; } - /** * A special ultra-optimized versions that knows it is hashing exactly * 3 words. * * @param a - * First word to calcuate hash of. + * First word to calculate hash of. * @param b - * Second word to calcuate hash of. + * Second word to calculate hash of. * @param c - * Third word to calcuate hash of. + * Third word to calculate hash of. * @param initval * Initialising value of hash. * @return @@ -197,17 +364,7 @@ rte_jhash2(uint32_t *k, uint32_t length, uint32_t initval) static inline uint32_t rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval) { - a += RTE_JHASH_GOLDEN_RATIO; - b += RTE_JHASH_GOLDEN_RATIO; - c += initval; - - __rte_jhash_mix(a, b, c); - - /* - * NOTE: In particular the "c += length; __rte_jhash_mix(a,b,c);" - * normally done at the end is not done here. - */ - return c; + return __rte_jhash_3words(a + 12, b + 12, c + 12, initval); } /** @@ -215,9 +372,9 @@ rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval) * 2 words. * * @param a - * First word to calcuate hash of. + * First word to calculate hash of. * @param b - * Second word to calcuate hash of. + * Second word to calculate hash of. * @param initval * Initialising value of hash. * @return @@ -226,7 +383,7 @@ rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval) static inline uint32_t rte_jhash_2words(uint32_t a, uint32_t b, uint32_t initval) { - return rte_jhash_3words(a, b, 0, initval); + return __rte_jhash_3words(a + 8, b + 8, 8, initval); } /** @@ -234,7 +391,7 @@ rte_jhash_2words(uint32_t a, uint32_t b, uint32_t initval) * 1 word. * * @param a - * Word to calcuate hash of. + * Word to calculate hash of. * @param initval * Initialising value of hash. * @return @@ -243,7 +400,7 @@ rte_jhash_2words(uint32_t a, uint32_t b, uint32_t initval) static inline uint32_t rte_jhash_1word(uint32_t a, uint32_t initval) { - return rte_jhash_3words(a, 0, 0, initval); + return __rte_jhash_3words(a + 4, 4, 4, initval); } #ifdef __cplusplus