Re: vhpt_miss handler question?

From: Mario Smarduch <cms063_at_email.mot.com>
Date: 2003-09-27 01:41:13
Keith Owens wrote:

> On Fri, 26 Sep 2003 09:43:55 -0500,
> Mario Smarduch <cms063@email.mot.com> wrote:
> >Some work I'm doing has taken me to the vhpt_miss
> >handler. I've been looking at  the following snippet just
> >wondering what happens in the case where the present
> >bit is 0 and p10,p11 predicates are not set anotherwords
> >they retain their application values. Would this not
> >cause an errant insertion if either p10 or p11 were
> >true in the application prior to the VHPT handler?
>
> >(p7)    tbit.nz.unc p10,p11=r19,32              // is it an instruction
>
> tbit.xx.unc sets both predicates to 0 if the controlling predicate is
> false.  See the 'else' clause on page 3:229 of Document Number:
> 245319-004 (ia64 Volume 3: Instruction Set Reference).

I understand the unc sets bot predicates to 0. The question
was regarding p7=false, but it appears in that case a TLB
entry with present bit set to 0 may be inserted which appears
to be harmless (other then taking up a TC entry).

Sorry for the noise :)

- mario.

-
To unsubscribe from this list: send the line "unsubscribe linux-ia64" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Received on Fri Sep 26 11:40:46 2003

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:18 EST