From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id 1AE40E72 for ; Tue, 5 May 2015 16:44:02 +0200 (CEST) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga101.fm.intel.com with ESMTP; 05 May 2015 07:43:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,373,1427785200"; d="scan'208";a="724018469" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by orsmga002.jf.intel.com with ESMTP; 05 May 2015 07:43:56 -0700 Received: from sivswdev02.ir.intel.com (sivswdev02.ir.intel.com [10.237.217.46]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id t45Eht5o022797 for ; Tue, 5 May 2015 15:43:55 +0100 Received: from sivswdev02.ir.intel.com (localhost [127.0.0.1]) by sivswdev02.ir.intel.com with ESMTP id t45EhsHT021111 for ; Tue, 5 May 2015 15:43:54 +0100 Received: (from pdelarax@localhost) by sivswdev02.ir.intel.com with id t45EhsWA021107 for dev@dpdk.org; Tue, 5 May 2015 15:43:54 +0100 From: Pablo de Lara To: dev@dpdk.org Date: Tue, 5 May 2015 15:43:53 +0100 Message-Id: <1430837034-21031-6-git-send-email-pablo.de.lara.guarch@intel.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1430837034-21031-1-git-send-email-pablo.de.lara.guarch@intel.com> References: <1429874587-17939-1-git-send-email-pablo.de.lara.guarch@intel.com> <1430837034-21031-1-git-send-email-pablo.de.lara.guarch@intel.com> Subject: [dpdk-dev] [PATCH v3 5/6] hash: remove duplicated code X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 May 2015 14:44:04 -0000 rte_jhash is basically like _rte_jhash_2hashes but it returns only 1 hash, instead of 2. In order to remove duplicated code, rte_jhash calls _rte_jhash_2hashes, passing 0 as the second seed and returning just the first hash value. (performance penalty is negligible) The same is done with rte_jhash2. Also, rte_jhash2 is just an specific case where keys are multiple of 32 bits, and where no key alignment check is required. So,to avoid duplicated code, the function calls _rte_jhash_2hashes with check_align = 0 (to use the optimal path) Signed-off-by: Pablo de Lara --- lib/librte_hash/rte_jhash.h | 283 ++++++++++--------------------------------- 1 files changed, 62 insertions(+), 221 deletions(-) diff --git a/lib/librte_hash/rte_jhash.h b/lib/librte_hash/rte_jhash.h index 9e82d06..6f05c4c 100644 --- a/lib/librte_hash/rte_jhash.h +++ b/lib/librte_hash/rte_jhash.h @@ -108,22 +108,8 @@ 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; union { @@ -132,12 +118,18 @@ rte_jhash(const void *key, uint32_t length, uint32_t initval) } u; /* 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; u.ptr = key; - /* Check key alignment. For x86 architecture, first case is always optimal */ - if (!strcmp(RTE_ARCH,"x86_64") || !strcmp(RTE_ARCH,"i686") || (u.i & 0x3) == 0) { + /* + * Check key alignment. For x86 architecture, first case is always optimal + * If check_align is not set, first case will be used + */ + + if ((!strcmp(RTE_ARCH,"x86_64") || !strcmp(RTE_ARCH,"i686") + || (!check_align) || (u.i & 0x3) == 0)) { const uint32_t *k = (const uint32_t *)key; while (length > 12) { @@ -178,7 +170,9 @@ 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 { const uint8_t *k = (const uint8_t *)key; @@ -233,63 +227,16 @@ rte_jhash(const void *key, uint32_t length, uint32_t initval) a += ((uint32_t)k[0]) << RTE_JHASH_BYTE0_SHIFT; break; 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]; - case 2: - b += k[1]; - case 1: - a += k[0]; - __rte_jhash_final(a, b, c); - /* case 0: nothing left to add */ - case 0: - break; - }; - - return c; + *pc = c; + *pb = b; } /** @@ -310,127 +257,7 @@ 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; - union { - const void *ptr; - size_t i; - } u; - - /* Set up the internal state */ - a = b = c = RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + *pc; - c += *pb; - - u.ptr = key; - - /* Check key alignment. For x86 architecture, first case is always optimal */ - if (!strcmp(RTE_ARCH,"x86_64") || !strcmp(RTE_ARCH,"i686") || (u.i & 0x3) == 0) { - const uint32_t *k = (const uint32_t *)key; - - 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 { - const uint8_t *k = (const uint8_t *)key; - - /* all but the last block: affect some 32 bits of (a, b, c) */ - while (length > 12) { - a += ((uint32_t)k[0]) << RTE_JHASH_BYTE0_SHIFT; - a += ((uint32_t)k[1]) << RTE_JHASH_BYTE1_SHIFT; - a += ((uint32_t)k[2]) << RTE_JHASH_BYTE2_SHIFT; - a += ((uint32_t)k[3]) << RTE_JHASH_BYTE3_SHIFT; - b += ((uint32_t)k[4]) << RTE_JHASH_BYTE0_SHIFT; - b += ((uint32_t)k[5]) << RTE_JHASH_BYTE1_SHIFT; - b += ((uint32_t)k[6]) << RTE_JHASH_BYTE2_SHIFT; - b += ((uint32_t)k[7]) << RTE_JHASH_BYTE3_SHIFT; - c += ((uint32_t)k[8]) << RTE_JHASH_BYTE0_SHIFT; - c += ((uint32_t)k[9]) << RTE_JHASH_BYTE1_SHIFT; - c += ((uint32_t)k[10]) << RTE_JHASH_BYTE2_SHIFT; - c += ((uint32_t)k[11]) << RTE_JHASH_BYTE3_SHIFT; - - __rte_jhash_mix(a, b, c); - - k += 12; - length -= 12; - } - - /* last block: affect all 32 bits of (c) */ - /* all the case statements fall through */ - switch (length) { - case 12: - c += ((uint32_t)k[11]) << RTE_JHASH_BYTE3_SHIFT; - case 11: - c += ((uint32_t)k[10]) << RTE_JHASH_BYTE2_SHIFT; - case 10: - c += ((uint32_t)k[9]) << RTE_JHASH_BYTE1_SHIFT; - case 9: - c += ((uint32_t)k[8]) << RTE_JHASH_BYTE0_SHIFT; - case 8: - b += ((uint32_t)k[7]) << RTE_JHASH_BYTE3_SHIFT; - case 7: - b += ((uint32_t)k[6]) << RTE_JHASH_BYTE2_SHIFT; - case 6: - b += ((uint32_t)k[5]) << RTE_JHASH_BYTE1_SHIFT; - case 5: - b += ((uint32_t)k[4]) << RTE_JHASH_BYTE0_SHIFT; - case 4: - a += ((uint32_t)k[3]) << RTE_JHASH_BYTE3_SHIFT; - case 3: - a += ((uint32_t)k[2]) << RTE_JHASH_BYTE2_SHIFT; - case 2: - a += ((uint32_t)k[1]) << RTE_JHASH_BYTE1_SHIFT; - case 1: - a += ((uint32_t)k[0]) << RTE_JHASH_BYTE0_SHIFT; - break; - 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); } /** @@ -451,40 +278,54 @@ rte_jhash_2hashes(const void *key, uint32_t length, uint32_t *pc, uint32_t *pb) static inline void rte_jhash2_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. + * + * @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_jhash2(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]; - case 2: - b += k[1]; - case 1: - a += k[0]; - __rte_jhash_final(a, b, c); - /* case 0: nothing left to add */ - case 0: - break; - }; + rte_jhash2_2hashes(k, length, &initval, &initval2); - *pc = c; - *pb = b; + return initval; } static inline uint32_t -- 1.7.4.1