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 1F42712A8 for ; Wed, 6 May 2015 11:36:34 +0200 (CEST) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP; 06 May 2015 02:36:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,379,1427785200"; d="scan'208";a="690694829" Received: from irsmsx151.ger.corp.intel.com ([163.33.192.59]) by orsmga001.jf.intel.com with ESMTP; 06 May 2015 02:36:31 -0700 Received: from irsmsx108.ger.corp.intel.com ([169.254.11.246]) by IRSMSX151.ger.corp.intel.com ([169.254.4.46]) with mapi id 14.03.0224.002; Wed, 6 May 2015 10:36:30 +0100 From: "De Lara Guarch, Pablo" To: "Ananyev, Konstantin" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [PATCH v3 3/6] hash: update jhash function with the latest available Thread-Index: AQHQh0IcxrpWfsqwIk2tsC22UwLuBp1uCfUAgAChIUA= Date: Wed, 6 May 2015 09:36:29 +0000 Message-ID: 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> <1430837034-21031-4-git-send-email-pablo.de.lara.guarch@intel.com> <2601191342CEEE43887BDE71AB97725821424ED1@irsmsx105.ger.corp.intel.com> In-Reply-To: <2601191342CEEE43887BDE71AB97725821424ED1@irsmsx105.ger.corp.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [163.33.239.182] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3 3/6] hash: update jhash function with the latest available 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: Wed, 06 May 2015 09:36:35 -0000 Hi Konstantin, > -----Original Message----- > From: Ananyev, Konstantin > Sent: Wednesday, May 06, 2015 1:36 AM > To: De Lara Guarch, Pablo; dev@dpdk.org > Subject: RE: [dpdk-dev] [PATCH v3 3/6] hash: update jhash function with t= he > latest available >=20 >=20 > Hi Pablo, >=20 > > -----Original Message----- > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Pablo de Lara > > Sent: Tuesday, May 05, 2015 3:44 PM > > To: dev@dpdk.org > > Subject: [dpdk-dev] [PATCH v3 3/6] hash: update jhash function with the > latest available > > > > Jenkins hash function was developed originally in 1996, > > and was integrated in first versions of DPDK. > > The function has been improved in 2006, > > achieving up to 60% better performance, compared to the original one. > > > > This patch integrates that code into the rte_jhash library. > > > > Signed-off-by: Pablo de Lara > > --- > > lib/librte_hash/rte_jhash.h | 261 > +++++++++++++++++++++++++++++++------------ > > 1 files changed, 188 insertions(+), 73 deletions(-) > > > > diff --git a/lib/librte_hash/rte_jhash.h b/lib/librte_hash/rte_jhash.h > > index a4bf5a1..0e96b7c 100644 > > --- a/lib/librte_hash/rte_jhash.h > > +++ b/lib/librte_hash/rte_jhash.h > > @@ -1,7 +1,7 @@ > > /*- > > * BSD LICENSE > > * > > - * Copyright(c) 2010-2014 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 withou= t > > @@ -45,38 +45,68 @@ extern "C" { > > #endif > > > > #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 look= up. > > + * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and fina= l() > > + * are externally useful functions. Routines to test the hash are inc= luded > > + * if SELF_TEST is defined. You can use this free for any purpose. I= t'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 -=3D b; a -=3D c; a ^=3D (c>>13); \ > > - b -=3D c; b -=3D a; b ^=3D (a<<8); \ > > - c -=3D a; c -=3D b; c ^=3D (b>>13); \ > > - a -=3D b; a -=3D c; a ^=3D (c>>12); \ > > - b -=3D c; b -=3D a; b ^=3D (a<<16); \ > > - c -=3D a; c -=3D b; c ^=3D (b>>5); \ > > - a -=3D b; a -=3D c; a ^=3D (c>>3); \ > > - b -=3D c; b -=3D a; b ^=3D (a<<10); \ > > - c -=3D a; c -=3D b; c ^=3D (b>>15); \ > > + a -=3D c; a ^=3D rot(c, 4); c +=3D b; \ > > + b -=3D a; b ^=3D rot(a, 6); a +=3D c; \ > > + c -=3D b; c ^=3D rot(b, 8); b +=3D a; \ > > + a -=3D c; a ^=3D rot(c, 16); c +=3D b; \ > > + b -=3D a; b ^=3D rot(a, 19); a +=3D c; \ > > + c -=3D b; c ^=3D rot(b, 4); b +=3D a; \ > > +} while (0) > > + > > +#define __rte_jhash_final(a, b, c) do { \ > > + c ^=3D b; c -=3D rot(b, 14); \ > > + a ^=3D c; a -=3D rot(c, 11); \ > > + b ^=3D a; b -=3D rot(a, 25); \ > > + c ^=3D b; c -=3D rot(b, 16); \ > > + a ^=3D c; a -=3D rot(c, 4); \ > > + b ^=3D a; b -=3D rot(a, 14); \ > > + c ^=3D b; c -=3D 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 =3D=3D RTE_LITTLE_ENDIAN > > +#define RTE_JHASH_BYTE0_SHIFT 0 > > +#define RTE_JHASH_BYTE1_SHIFT 8 > > +#define RTE_JHASH_BYTE2_SHIFT 16 > > +#define RTE_JHASH_BYTE3_SHIFT 24 > > +#else > > +#define RTE_JHASH_BYTE0_SHIFT 24 > > +#define RTE_JHASH_BYTE1_SHIFT 16 > > +#define RTE_JHASH_BYTE2_SHIFT 8 > > +#define RTE_JHASH_BYTE3_SHIFT 0 > > +#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) > > > > /** > > * The most generic version, hashes an arbitrary sequence > > @@ -95,42 +125,119 @@ 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 =3D (const uint8_t *)key; > > - const uint32_t *k32 =3D (const uint32_t *)key; > > + uint32_t a, b, c; > > + union { > > + const void *ptr; > > + size_t i; > > + } u; > > > > - len =3D length; > > - a =3D b =3D RTE_JHASH_GOLDEN_RATIO; > > - c =3D initval; > > + /* Set up the internal state */ > > + a =3D b =3D c =3D RTE_JHASH_GOLDEN_RATIO + ((uint32_t)length) + initv= al; > > > > - while (len >=3D 12) { > > - a +=3D k32[0]; > > - b +=3D k32[1]; > > - c +=3D k32[2]; > > + u.ptr =3D key; > > > > - __rte_jhash_mix(a,b,c); > > + /* Check key alignment. For x86 architecture, first case is always > optimal */ > > + if (!strcmp(RTE_ARCH,"x86_64") || !strcmp(RTE_ARCH,"i686") || (u.i > & 0x3) =3D=3D 0) { >=20 > Wonder why strcmp(), why not something like: 'if defined(RTE_ARCH_I686) > || defined(RTE_ARCH_X86_64)' as in all other places? > Another question what would be in case of RTE_ARCH=3D"x86_x32"? > Konstantin Functionally is the same and using this method, I can integrate all conditi= ons in one line, so it takes less code. I also checked the assembly code, and the compiler removes the check if it = is Intel architecture, so performance remains the same. Re x86_x32, you are right, probably I need to include it. Although, I just = realized that it is not used in any other place. Wonder if we should include it somewhere else? E.g. rte_hash_crc.h