On Thu, 28 Oct 1999, Jason Thorpe wrote:

> On Thu, 28 Oct 1999 21:32:51 -0400 (EDT) 
>  Andrew Gallatin <[EMAIL PROTECTED]> wrote:
> 
>  > exception_return & skipped the ipl lowering & the check for an ast
>  > since I don't think you're ever going to need to check for an ast
>  > after an interrupt.  
> 
> Nonsense.  ASTs are a key part of process scheduling, and I'd bet that
> you run into strange scheduling behaviour if you don't deal with ASTs
> after e.g. clock interrupts.

Thats correct. The problem is that we are calling the AST with interrupts
enabled which allows unbounded interrupt recursion. This is true in NetBSD
(at least in version 1.60 of locore.s) as well. The whole idea of ASTs and
SWIs is an awful hangover from the VAX; there must be a better way.

--
Doug Rabson                             Mail:  [EMAIL PROTECTED]
Nonlinear Systems Ltd.                  Phone: +44 181 442 9037




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