Path: utzoo!attcan!uunet!cs.utexas.edu!uwm.edu!psuvax1!husc6!encore!pinocchio.encore.com From: jkenton@pinocchio.encore.com (Jeff Kenton) Newsgroups: comp.arch Subject: Re: Interrupts in user space Message-ID: <12738@encore.Encore.COM> Date: 17 Sep 90 13:53:28 GMT References: Sender: news@Encore.COM Lines: 21 From article , by moss@cs.umass.edu (Eliot Moss): > In article <2128@key.COM> sjc@key.COM (Steve Correll) writes: > > Well, Prof. Rubin _did_ ask for an "interrupt", and most Unix kernels insist > on being involved in any interrupts. And Unix is not unique in this. > > My reaction is that there is no reason why an interrupt of this kind need go > through the OS kernel. With the recent RISC chips (88000, MIPS and i860 come to mind) the overhead of getting the machine state safely saved away in the low level exception code is substantial. You have to do this anyway before you can hand off control to the user program "without going into the OS kernel", so the savings don't amount to much. ----- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ----- ----- jeff kenton --- temporarily at jkenton@pinocchio.encore.com ----- ----- --- always at (617) 894-4508 --- ----- ----- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -----