Support for Intel X1000

[Florian Weimer]

On 05/12/2015 12:28 PM, Kinsella, Ray wrote:

> 1. Not using the LOCK prefix on the Intel X1000.  This can be achieved 
> either by defining UP (uniprocessor) or telling the assembler to omit
> the LOCK prefix "momit-lock-prefix=yes". 

We might have places where the instruction layout matters (not sure
about that).  It might not be as simple as flipping a compiler switch.

> 2. OS builders creating a UP version of glibc targeted for the X1000. 
> The runtime linker then decides which glibc to load based on a HWCAP, 
> in a similar way to how the Xen specific glibc is loaded.

I think the two cases are not really comparable.  Back in those days,
access to thread-local variables was pretty rare and mostly restricted
to glibc.

Nowadays, you'd have to recompile a whole distribution to get rid of
atomics everywhere, and I can't really see any of the major
distributions doing that.

-- 
Florian Weimer / Red Hat Product Security