Re: Availability of kdb

From: Jamie Lokier (lk@tantalophile.demon.co.uk)
Date: Mon Sep 11 2000 - 11:43:50 EST


Jeff V. Merkey wrote:
> This means it completely unnecessary to assert LOCK# for the unlock
> case, since there are no ordering issues persay - the other processors
> are spinning on the lock already and cannot get through.

Yes I know I left out the context. Doesn't change what I'm about to
say. Erm, this does not appear to address ordering between the spinlock
and access to _other_ memory locations. I know you're right and your
information is very interesting, but it doesn't appear to address the
point... only knowledge of processor ordering tells us that `movb' for
spin-unlock always flushes prior pending writes before unlocking.

That's something that comes from manuals etc. and indeed, the _bugs_ in
that show up on the scopes (circa 1994 as you said).

-- Jamie
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Fri Sep 15 2000 - 21:00:15 EST