Richard Henderson <r...@twiddle.net> writes:
> On 01/19/2017 09:04 AM, Alex Bennée wrote:
>> +void qemu_tcg_configure(QemuOpts *opts, Error **errp)
>> +{
>> + const char *t = qemu_opt_get(opts, "thread");
>> + if (t) {
>> + if (strcmp(t, "multi") == 0) {
>> + if (TCG_OVERSIZED_GUEST) {
>> + error_setg(errp, "No MTTCG when guest word size > hosts");
>
> I agree with this, since I don't ever imagine it'll be fixed. It's a silly
> use
> case in the first place considering the ubiquity of 64-bit hosts.
Funnily enough I know one kernel hacker who does use this to test their
arm64 kernels on their re-purposed armhf chromebooks. I've already
explained coming their way ;-)
>
>> + } else if (!check_tcg_memory_orders_compatible()) {
>> + error_setg(errp,
>> + "No MTTCG when guest MO is stronger than host
>> MO");
>
> This, on the other hand, means that one cannot even force multi for testing.
> A
> warning perhaps?
I did toy with making that a warning when I first wrote it. I'll make it so.
> And how shall we handle a guest translate adding barriers as
> necessary to satisfy host memory ordering?
We are talking about doing the necessary annotation to all a givens
targets loads and stores? I figured this code would morph and be tweaked
when (if?) we get there.
--
Alex Bennée
