From owner-freebsd-hackers@freebsd.org Wed Mar 1 08:14:44 2017 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 282F4CF2A96 for ; Wed, 1 Mar 2017 08:14:44 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from vps1.elischer.org (vps1.elischer.org [204.109.63.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "vps1.elischer.org", Issuer "CA Cert Signing Authority" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 0D192DB4; Wed, 1 Mar 2017 08:14:43 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from Julian-MBP3.local (220-253-188-71.dyn.iinet.net.au [220.253.188.71]) (authenticated bits=0) by vps1.elischer.org (8.15.2/8.15.2) with ESMTPSA id v218EZJ2018411 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Wed, 1 Mar 2017 00:14:38 -0800 (PST) (envelope-from julian@freebsd.org) Subject: Re: [GSoC 2017] Original proposal: Port kernel Lua to FreeBSD To: Warner Losh , Allan Jude References: <244231A2-EB18-4E58-A2B2-927F55D54950@FreeBSD.org> Cc: "freebsd-hackers@freebsd.org" , Saurav Sachidanand From: Julian Elischer Message-ID: Date: Wed, 1 Mar 2017 16:14:29 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Mar 2017 08:14:44 -0000 On 28/2/17 2:01 am, Warner Losh wrote: > On Mon, Feb 27, 2017 at 8:26 AM, Allan Jude wrote: >> On February 27, 2017 5:28:41 AM PST, Saurav Sachidanand wrote: >>> Hello FreeBSD community, >>> >>> I'm >>> Saurav Sachidanand, and I'm >>> a CS sophomore studying in India >>> . >>> I have an interest in operating systems development and wish to >>> contribute >>> to the FreeBSD community. I'm proficient with C and have some >>> experience in >>> kernel programming. Hence, I'd like to propose an original project for >>> GSoC >>> 2017 that I feel would benefit this community. >>> >>> In past years, the Lua interpreter was ported to run inside the Linux >>> and >>> NetBSD kernel [1]. Lua was chosen because it's interpreter is very >>> small (~240 >>> KB) compared to that of Python or Ruby, it's MIT licensed, and is >>> almost >>> freestanding. A working demonstration of it is a packet filtering >>> algorithm >>> written entirely in kernel Lua [2]. >>> >>> Specifically, my proposal would be to port the following that are >>> currently >>> written for NetBSD: >>> - the modified Lua VM source code with _KERNEL preprocessor directives >>> to >>> exclude user-space functionality like floating point, the io and os >>> module >>> in the standard library, etc. [3] >>> - the kernel module device driver for /dev/lua, to which Lua scripts >>> are >>> fed to be executed [4], [5] >>> - the luactl user-space program to control the Lua device and a couple >>> of >>> sysctl variables which serve similar purpose [6], [7] >>> >>> And then: >>> - run the Lua test suite targeting whatever we support in the kernel to >>> make sure it works [8] >>> - and write Lua bindings to the kernel interfaces that would interest >>> the >>> FreeBSD community >>> >>> Since NetBSD and FreeBSD have similar kernel interfaces (mutexes, >>> linked >>> lists, device switch interface), the porting shouldn't involve too much >>> code refactoring. Also, this would all be an experiment in that we >>> don't >>> fully know what the real world use cases might be, but it would attract >>> more people to writing kernel code who otherwise wouldn't because of >>> having >>> to do everything in C. And it would be interesting to carry out it out >>> in >>> FreeBSD as well since it has a larger community than NetBSD. >>> >>> I humbly request anyone who is interested in this project to be my >>> potential mentor(s) for GSoC. >>> >>> More slides on kernel Lua in NetBSD - [9], [10]. >>> >>> Thanks, >>> Saurav >>> >>> [1] - http://www.netbsd.org/~lneto/dls14.pdf >>> [2] - https://www.netbsd.org/~lneto/eurobsdcon14.pdf >>> [3] - https://github.com/jsonn/src/tree/trunk/external/mit/lua/dist/src >>> [4] - >>> https://github.com/IIJ-NetBSD/netbsd-src/tree/master/sys/modules/lua >>> [5] - >>> https://github.com/IIJ-NetBSD/netbsd-src/tree/master/sys/modules/luasystm >>> [6] - https://github.com/IIJ-NetBSD/netbsd-src/tree/master/sbin/luactl >>> [7] - http://netbsd.gw.com/cgi-bin/man-cgi?lua+4+NetBSD-current >>> [8] - http://www.lua.org/tests/ >>> [9] - >>> https://www.netbsd.org/gallery/presentations/mbalmer/fosdem2012/kernel_mode_lua.pdf >>> [10] - https://www.lua.org/wshop13/Cormack.pdf >>> _______________________________________________ >>> freebsd-hackers@freebsd.org mailing list >>> https://lists.freebsd.org/mailman/listinfo/freebsd-hackers >>> To unsubscribe, send any mail to >>> "freebsd-hackers-unsubscribe@freebsd.org" >> This may be quite a nice thing to have. Another upcoming use for LUA in the kernel is ZFS Channel Programs. These allow a number of ZFS operations to be completed as a single atomic transaction. >> >> I would hope we could structure this in such a way as to not end up with two copies of Lua in the kernel. > There's also a 3/4 finished lua in the boot loader that you might be > able to leverage as well.... I'd like to see that finished. While Devin has done Heroic work with the forth in the loader, I think it's time has come. It' be nice to have something a little less '60s. > > Warner > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" >