Date: Sat, 4 Jan 1997 11:51:27 +1100 (EST) From: John Birrell <jb@cimlogic.com.au> To: joerg_wunsch@uriah.heep.sax.de Cc: current@FreeBSD.ORG Subject: Re: kernel w/o source? [MOD_DECL in lkm.h] Message-ID: <199701040051.LAA28752@freebsd1.cimlogic.com.au> In-Reply-To: <Mutt.19970104000318.j@uriah.heep.sax.de> from J Wunsch at "Jan 4, 97 00:03:18 am"
next in thread | previous in thread | raw e-mail | index | archive | help
J Wunsch wrote: > Define `universal'. Default? I dunno, the crystal ball was a little fuzzy. 8-) > Second, you can't have compile-time options anymore then. IOW, you > gotta include everything into the compiled object already, to make it > run-time selectable. I'm not sure that I agree with this. For DEBUG and DIAGNOSTIC maybe, but most of the options involve linking in code (or not) and filling in device arrays. Once you make most options loadable as kernel modules, you have achieved much of the goal of "building" a kernel without source because you don't need to build one in the first place. If the next WC CD came out with a minimal generic kernel (that was enough to get console & disk working) and everything else as lkms, then I would most likely _never_ build a kernel because my development work is done in user-space (except for few simple lkms which I can't configure properly 'cause of the way the system is designed. Sigh). I wonder what percentage of FreeBSD users/hackers actually do kernel development? And of those that don't, what percentage configure their kernels with exactly those options that they currently *need* rather than throwing in a few that they *might* need? > People might suddenly get the feeling that > there's now also the kitchen-sink included. :) The kitchen-sink -- that'd be an lkm wouldn't it?! Nice to have the feeling that you could load it if you needed it, eh? > And, if being faced > with a compile-time vs. run-time decision, the latter usually actually > _costs_ run-time. So the kernel won't be only more bloated, but also > slower. For DEBUG and DIAGNOSTIC, yes. For what other options is there _inline_ (and therefore _costly_) code? No doubt there are a few, but are there so many combinations of these options that you can't build a few typical modules for those who don't want to have to build them. Looking at some of the kernel source, I'd say that sys/net/if_ethersubr.c would be one with the most options, but much of that is just switch-case entries (which take space but don't cost speed). Those who want that configured with *exactly* their specified options can build it themselves. Does FreeBSD *really* have to be a system that only nurds play with? 8-) [blows dust of old Motorola system] Now, how do I boot this SysV thingy? Sigh. It still works, damn! 8-) > > -- > cheers, J"org > > joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE > Never trust an operating system you don't have sources for. ;-) / \ available 8-) Regards, -- John Birrell CIMlogic Pty Ltd jb@cimlogic.com.au; jb@netbsd.org 119 Cecil Street Ph +61 3 9690 6900 South Melbourne Vic 3205 Fax +61 3 9690 6650 Australia Mob +61 18 353 137
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199701040051.LAA28752>