Andrew Hobgood wrote:

> > The other option is to implement TAS as a syscall on mips (as at
> > least Ultrix does).  I put in a half-hearted attempt in the past
> > to make a generic MI atomic interface - maybe the ``solution'' for
> > now is a MIPS-only sysarch() call...
> 
> if you could turn off interrupts [ ... ]

That's the key statement.  In userland, you can't turn off interrupts
at all - only the kernel can, hence the idea of a syscall.

Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
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