[Pkg-libvirt-maintainers] Bug#691784: Bug#691784: [virt-manager] make spice optional (on !linux-{i386, amd64})

[Hilko Bengen]

* Guido Günther:

>> Why is spice only available for amd64 and i386 in the first place? I
>> have a vague recollection about x86-only assembly language snippets
>> that reeked of micro-optimization -- is that still the problem?
>
> Yes, for locking primitives I think, Lets better ask the maintainer (cc:)

Okay, I just checked:

1. spice-common/common/bitops.h uses x86 assembly for
spice_bit_find_msb(), but a portable C implementation is provided as an
alternative.

2. spice-common/spice-protocol/spice/macros.h provides some byteswap
macros, but there are also portable C alternatives for those.

3. spice-common/spice-protocol/spice/barrier.h contains memory barrier
primitives.

I suspect micro-optimizations in the first two cases, but there are
portable alternatives, they don't hurt. 

Memory barrier equivalents for other architectures can be easily found
-- in the Linux kernel tree among other places.

Cheers,
-Hilko