X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_hash%2Frte_jhash.h;h=3eca13858b39222224675767a399b0cafd5c8c90;hb=77a217a19bb72860e26b9aefb19dce92239e0820;hp=62e276cc12efe2f779cbacf8f9c39af064acccd7;hpb=8718219a8737b8fccc784874358671515f7063bd;p=dpdk.git diff --git a/lib/librte_hash/rte_jhash.h b/lib/librte_hash/rte_jhash.h index 62e276cc12..3eca13858b 100644 --- a/lib/librte_hash/rte_jhash.h +++ b/lib/librte_hash/rte_jhash.h @@ -46,6 +46,9 @@ extern "C" { #include #include +#include + +#include #include /* jhash.h: Jenkins hash support. @@ -102,38 +105,28 @@ extern "C" { #define LOWER16b_MASK rte_le_to_cpu_32(0xffff) #define LOWER24b_MASK rte_le_to_cpu_32(0xffffff) -/** - * The most generic version, hashes an arbitrary sequence - * of bytes. No alignment or length assumptions are made about - * the input key. - * - * @param key - * Key to calculate hash of. - * @param length - * Length of key in bytes. - * @param initval - * Initialising value of hash. - * @return - * Calculated hash value. - */ -static inline uint32_t -rte_jhash(const void *key, uint32_t length, uint32_t initval) +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) + initval; + a = b = c = RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + *pc; + c += *pb; - /* Check key alignment. For x86 architecture, first case is always optimal */ + /* + * 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 = key; + 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 *k = (uint32_t *)((uintptr_t)key & (uintptr_t)~3); const uint32_t s = ((uintptr_t)key & 3) * CHAR_BIT; #endif - - if (s == 0) { + if (!check_align || s == 0) { while (length > 12) { a += k[0]; b += k[1]; @@ -172,7 +165,9 @@ rte_jhash(const void *key, uint32_t length, uint32_t initval) a += k[0] & LOWER8b_MASK; break; /* zero length strings require no mixing */ case 0: - return c; + *pc = c; + *pb = b; + return; }; } else { /* all but the last block: affect some 32 bits of (a, b, c) */ @@ -238,66 +233,16 @@ rte_jhash(const void *key, uint32_t length, uint32_t initval) break; /* zero length strings require no mixing */ case 0: - return c; + *pc = c; + *pb = b; + return; } } __rte_jhash_final(a, b, c); - return c; -} - -/** - * A special optimized version that handles 1 or more of uint32_ts. - * The length parameter here is the number of uint32_ts in the key. - * - * @param k - * Key to calculate hash of. - * @param length - * Length of key in units of 4 bytes. - * @param initval - * Initialising value of hash. - * @return - * Calculated hash value. - */ -static inline uint32_t -rte_jhash2(const uint32_t *k, uint32_t length, uint32_t initval) -{ - uint32_t a, b, c; - - /* Set up the internal state */ - a = b = c = RTE_JHASH_GOLDEN_RATIO + (((uint32_t)length) << 2) + initval; - - /* Handle most of the key */ - while (length > 3) { - a += k[0]; - b += k[1]; - c += k[2]; - - __rte_jhash_mix(a, b, c); - - k += 3; - length -= 3; - } - - /* Handle the last 3 uint32_t's */ - switch (length) { - case 3: - c += k[2]; - /* Fallthrough */ - case 2: - b += k[1]; - /* Fallthrough */ - case 1: - a += k[0]; - __rte_jhash_final(a, b, c); - /* Fallthrough */ - /* case 0: nothing left to add */ - case 0: - break; - }; - - return c; + *pc = c; + *pb = b; } /** @@ -318,145 +263,14 @@ rte_jhash2(const uint32_t *k, uint32_t length, uint32_t initval) static inline void rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, uint32_t *pb) { - 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 defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_I686) || defined(RTE_ARCH_X86_X32) - const uint32_t *k = 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 (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; + __rte_jhash_2hashes(key, length, pc, pb, 1); } /** - * Same as rte_jhash2, but takes two seeds and return two uint32_ts. + * 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_jhash2. + * the same as the return value from rte_jhash_32b. * * @param k * Key to calculate hash of. @@ -468,45 +282,59 @@ rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, uint32_t *pb) * IN: second seed OUT: secondary hash value. */ static inline void -rte_jhash2_2hashes(const uint32_t *k, uint32_t length, uint32_t *pc, uint32_t *pb) +rte_jhash_32b_2hashes(const uint32_t *k, uint32_t length, uint32_t *pc, uint32_t *pb) { - uint32_t a, b, c; + __rte_jhash_2hashes((const void *) k, (length << 2), pc, pb, 0); +} - /* Set up the internal state */ - a = b = c = RTE_JHASH_GOLDEN_RATIO + (((uint32_t)length) << 2) + *pc; - c += *pb; +/** + * The most generic version, hashes an arbitrary sequence + * of bytes. No alignment or length assumptions are made about + * the input key. For keys not aligned to four byte boundaries + * or a multiple of four bytes in length, the memory region + * just after may be read (but not used in the computation). + * This may cross a page boundary. + * + * @param key + * Key to calculate hash of. + * @param length + * Length of key in bytes. + * @param initval + * Initialising value of hash. + * @return + * Calculated hash value. + */ +static inline uint32_t +rte_jhash(const void *key, uint32_t length, uint32_t initval) +{ + uint32_t initval2 = 0; - /* Handle most of the key */ - while (length > 3) { - a += k[0]; - b += k[1]; - c += k[2]; + rte_jhash_2hashes(key, length, &initval, &initval2); - __rte_jhash_mix(a, b, c); + return initval; +} - k += 3; - length -= 3; - } +/** + * A special optimized version that handles 1 or more of uint32_ts. + * The length parameter here is the number of uint32_ts in the key. + * + * @param k + * Key to calculate hash of. + * @param length + * Length of key in units of 4 bytes. + * @param initval + * Initialising value of hash. + * @return + * Calculated hash value. + */ +static inline uint32_t +rte_jhash_32b(const uint32_t *k, uint32_t length, uint32_t initval) +{ + uint32_t initval2 = 0; - /* Handle the last 3 uint32_t's */ - switch (length) { - case 3: - c += k[2]; - /* Fallthrough */ - case 2: - b += k[1]; - /* Fallthrough */ - case 1: - a += k[0]; - __rte_jhash_final(a, b, c); - /* Fallthrough */ - /* case 0: nothing left to add */ - case 0: - break; - }; + rte_jhash_32b_2hashes(k, length, &initval, &initval2); - *pc = c; - *pb = b; + return initval; } static inline uint32_t @@ -526,11 +354,11 @@ __rte_jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval) * 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 @@ -547,9 +375,9 @@ 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 @@ -566,7 +394,7 @@ 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