Date: Tue, 27 May 2008 15:30:28 -0700 From: "Peter Wemm" <peter@wemm.org> To: "Bruce M. Simpson" <bms@freebsd.org> Cc: Ed Schouten <ed@80386.nl>, current@freebsd.org, arch@freebsd.org, Poul-Henning Kamp <phk@phk.freebsd.dk>, Robert Watson <rwatson@freebsd.org>, Ade Lovett <ade@freebsd.org>, net@freebsd.org Subject: Re: HEAD UP: non-MPSAFE network drivers to be disabled (was: 8.0 network stack MPsafety goals (fwd)) Message-ID: <e7db6d980805271530y2462abf8p3727b1627d07b5f@mail.gmail.com> In-Reply-To: <483C2666.7010608@FreeBSD.org> References: <20080527062736.GF64397@hoeg.nl> <45633.1211870269@critter.freebsd.dk> <20080527064253.GG64397@hoeg.nl> <483C2666.7010608@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, May 27, 2008 at 8:19 AM, Bruce M. Simpson <bms@freebsd.org> wrote: > Ed Schouten wrote: >>>> >>>> With the word `should' I meant that it would still be possible to >>>> implement multiple line disciplines with the mpsafetty code. But I >>>> really think line disciplines should go. >>>> >>> >>> No, don't bother. Remove the entire "abstraction" of linedisciplines. >>> >> >> Your wish is my command. >> > > Like Julian and Robert said, please don't break Netgraph. > > It still needs to hook into tty at a very low level; and the components such > as Bluetooth which can use ttys for low level stream processing, are built > on Netgraph. > > Both SLIP and PPP can be built using Netgraph. > > Other than that, line disciplines can go away. I think line disciplines should go away as such. It would be nice to have a place to hook into (even linux has this), but the line discipline concept is 30 years stale. IMHO, priority #1 is give ttys the first class treatment they need, then priority #2 is to put in some low level hooks for ng_tty or whatever. It would be hard to come up with a more inconvenient interface than we have now. As an example.. look at the CAN_BYPASS_L_RINT stuff. If we had a way to pass a block of characters upstream instead of a single character at a time, then we could build this magic into the input routines instead of the device drivers. The bypass is still useful because it saves considerable cycles for raw tty modes, eg: userland ppp, zmodem upload/downloads etc etc. But the logic for it shouldn't have to be scattered all over the tree due to poor line discipline APIs. -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com "All of this is for nothing if we don't go to the stars" - JMS/B5 "If Java had true garbage collection, most programs would delete themselves upon execution." -- Robert Sewell
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?e7db6d980805271530y2462abf8p3727b1627d07b5f>