From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46220) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a3j1x-0007Rv-QT for qemu-devel@nongnu.org; Tue, 01 Dec 2015 06:23:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a3j1t-00061q-Kr for qemu-devel@nongnu.org; Tue, 01 Dec 2015 06:23:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39231) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a3j1t-00061j-E6 for qemu-devel@nongnu.org; Tue, 01 Dec 2015 06:23:29 -0500 Date: Tue, 1 Dec 2015 11:23:23 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20151201112322.GB26419@work-vm> References: <1448627251-11186-1-git-send-email-zhangchen.fnst@cn.fujitsu.com> <1448627251-11186-3-git-send-email-zhangchen.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <1448627251-11186-3-git-send-email-zhangchen.fnst@cn.fujitsu.com> Subject: Re: [Qemu-devel] [RFC PATCH 2/9] jhash: add linux kernel jhashtable in qemu List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Zhang Chen Cc: Li Zhijian , Gui jianfeng , Jason Wang , "eddie.dong" , qemu devel , Huang peng , Gong lei , Stefan Hajnoczi , jan.kiszka@siemens.com, zhanghailiang * Zhang Chen (zhangchen.fnst@cn.fujitsu.com) wrote: > From: zhangchen >=20 > This used by colo-proxy to save and lookup > connection info >=20 > Signed-off-by: zhangchen > --- > include/qemu/jhash.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++= ++++++ > 1 file changed, 52 insertions(+) > create mode 100644 include/qemu/jhash.h >=20 > diff --git a/include/qemu/jhash.h b/include/qemu/jhash.h > new file mode 100644 > index 0000000..f6cc7b3 > --- /dev/null > +++ b/include/qemu/jhash.h > @@ -0,0 +1,52 @@ > +/* > + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COL= O) > + * (a.k.a. Fault Tolerance or Continuous Replication) > + * > + * Copyright (c) 2015 HUAWEI TECHNOLOGIES CO., LTD. > + * Copyright (c) 2015 FUJITSU LIMITED > + * Copyright (c) 2015 Intel Corporation > + * > + * Author: Zhang Chen > + * > + * This work is licensed under the terms of the GNU GPL, version 2 or > + * later. See the COPYING file in the top-level directory. > + */ Please be careful with the copyright. This code is mostly a copy of the kernel code, so I think it should take th= e copyright =66rom the kernel code (see kernel's include/linux/jhash.h); and that copyr= ight states it's based on Bob Jenkins' Public Domain code. Normally we have a problem as well QEMU doesn't like taking GPL2 code from = the kernel, but my reading of the kernel's header file is that it's still Public domain= ; but I don't know what the right thing is to be sure. Dave > + > +#ifndef QEMU_JHASH_H__ > +#define QEMU_JHASH_H__ > + > +/* > + * hashtable relation copy from linux kernel jhash > + */ > +static inline uint32_t rol32(uint32_t word, unsigned int shift) > +{ > + return (word << shift) | (word >> (32 - shift)); > +} > + > +/* __jhash_mix -- mix 3 32-bit values reversibly. */ > +#define __jhash_mix(a, b, c) \ > +{ \ > + a -=3D c; a ^=3D rol32(c, 4); c +=3D b; \ > + b -=3D a; b ^=3D rol32(a, 6); a +=3D c; \ > + c -=3D b; c ^=3D rol32(b, 8); b +=3D a; \ > + a -=3D c; a ^=3D rol32(c, 16); c +=3D b; \ > + b -=3D a; b ^=3D rol32(a, 19); a +=3D c; \ > + c -=3D b; c ^=3D rol32(b, 4); b +=3D a; \ > +} > + > +/* __jhash_final - final mixing of 3 32-bit values (a,b,c) into c */ > +#define __jhash_final(a, b, c) \ > +{ \ > + c ^=3D b; c -=3D rol32(b, 14); \ > + a ^=3D c; a -=3D rol32(c, 11); \ > + b ^=3D a; b -=3D rol32(a, 25); \ > + c ^=3D b; c -=3D rol32(b, 16); \ > + a ^=3D c; a -=3D rol32(c, 4); \ > + b ^=3D a; b -=3D rol32(a, 14); \ > + c ^=3D b; c -=3D rol32(b, 24); \ > +} > + > +/* An arbitrary initial parameter */ > +#define JHASH_INITVAL 0xdeadbeef > + > +#endif /* QEMU_JHASH_H__ */ > --=20 > 1.9.1 >=20 >=20 >=20 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK