On Mon, Dec 18, 2017 at 12:10:41PM +0100, Greg Kurz wrote: > On Mon, 18 Dec 2017 20:20:20 +1100 > David Gibson <da...@gibson.dropbear.id.au> wrote: > > > This adds an spapr capability bit for Hardware Transactional Memory. It is > > enabled by default for pseries-2.11 and earlier machine types. with POWER8 > > or later CPUs (as it must be, since earlier qemu versions would implicitly > > allow it). However it is disabled by default for the latest pseries-2.12 > > machine type. > > > > This means that with the latest machine type, HTM will not be available, > > regardless of CPU, unless it is explicitly enabled on the command line. > > That change is made on the basis that: > > > > * This way running with -M pseries,accel=tcg will start with whatever cpu > > and will provide the same guest visible model as with accel=kvm. > > - More specifically, this means existing make check tests don't have > > to be modified to use cap-htm=off in order to run with TCG > > > > * We hope to add a new "HTM without suspend" feature in the not too > > distant future which could work on both POWER8 and POWER9 cpus, and > > could be enabled by default. > > > > * Best guesses suggest that future POWER cpus may well only support the > > HTM-without-suspend model, not the (frankly, horribly overcomplicated) > > POWER8 style HTM with suspend. > > > > * Anecdotal evidence suggests problems with HTM being enabled when it > > wasn't wanted are more common than being missing when it was. > > > > Signed-off-by: David Gibson <da...@gibson.dropbear.id.au> > > --- > > hw/ppc/spapr.c | 15 ++++++++++----- > > hw/ppc/spapr_caps.c | 29 ++++++++++++++++++++++++++++- > > include/hw/ppc/spapr.h | 3 +++ > > 3 files changed, 41 insertions(+), 6 deletions(-) > > > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > > index d472baef8d..f8fee8ebcf 100644 > > --- a/hw/ppc/spapr.c > > +++ b/hw/ppc/spapr.c > > @@ -253,7 +253,9 @@ static int spapr_fixup_cpu_numa_dt(void *fdt, int > > offset, PowerPCCPU *cpu) > > } > > > > /* Populate the "ibm,pa-features" property */ > > -static void spapr_populate_pa_features(PowerPCCPU *cpu, void *fdt, int > > offset, > > +static void spapr_populate_pa_features(sPAPRMachineState *spapr, > > While here, maybe you could rename spapr_populate_pa_features() to > spapr_dt_pa_features() ? > > But anyway, this isn't really the point of this series, so:
Yeah, I don't think that's really in scope for this series.
> Reviewed-by: Greg Kurz <gr...@kaod.org>
Thanks.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
signature.asc
Description: PGP signature
