On Tue, 15 Oct 2019 at 12:56, Beata Michalska
<beata.michal...@linaro.org> wrote:
>
> On Tue, 15 Oct 2019 at 11:56, Andrew Jones <drjo...@redhat.com> wrote:
> >
> > On Tue, Oct 15, 2019 at 10:59:16AM +0100, Beata Michalska wrote:
> > > On Tue, 1 Oct 2019 at 14:04, Andrew Jones <drjo...@redhat.com> wrote:
> > > > +
> > > > + obj = object_new(object_class_get_name(oc));
> > > > +
> > > > + if (qdict_in) {
> > > > + Visitor *visitor;
> > > > + Error *err = NULL;
> > > > +
> > > > + visitor = qobject_input_visitor_new(model->props);
> > > > + visit_start_struct(visitor, NULL, NULL, 0, &err);
> > > > + if (err) {
> > > > + object_unref(obj);
> > >
> > > Shouldn't we free the 'visitor' here as well ?
> >
> > Yes. Good catch. So we also need to fix
> > target/s390x/cpu_models.c:cpu_model_from_info(), which has the same
> > construction (the construction from which I derived this)
> >
> > >
> > > > + error_propagate(errp, err);
> > > > + return NULL;
> > > > + }
> > > > +
> >
> > What about the rest of the patch? With that fixed for v6 can I
> > add your r-b?
> >
>
> I still got this feeling that we could optimize that a bit - which I'm
> currently on, so hopefully I'll be able to add more comments soon if
> that proves to be the case.
>
> BR
> Beata
I think there are few options that might be considered though the gain
is not huge .. but it's always smth:
> +CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType
> type,
> + CpuModelInfo *model,
> + Error **errp)
> +{
> + CpuModelExpansionInfo *expansion_info;
> + const QDict *qdict_in = NULL;
> + QDict *qdict_out;
> + ObjectClass *oc;
> + Object *obj;
> + const char *name;
> + int i;
> +
> + if (type != CPU_MODEL_EXPANSION_TYPE_FULL) {
> + error_setg(errp, "The requested expansion type is not supported");
> + return NULL;
> + }
> +
> + if (!kvm_enabled() && !strcmp(model->name, "host")) {
> + error_setg(errp, "The CPU type '%s' requires KVM", model->name);
> + return NULL;
> + }
> +
> + oc = cpu_class_by_name(TYPE_ARM_CPU, model->name);
> + if (!oc) {
> + error_setg(errp, "The CPU type '%s' is not a recognized ARM CPU
> type",
> + model->name);
> + return NULL;
> + }
> +
> + if (kvm_enabled()) {
> + const char *cpu_type = current_machine->cpu_type;
> + int len = strlen(cpu_type) - strlen(ARM_CPU_TYPE_SUFFIX);
> + bool supported = false;
> +
> + if (!strcmp(model->name, "host") || !strcmp(model->name, "max")) {
> + /* These are kvmarm's recommended cpu types */
> + supported = true;
> + } else if (strlen(model->name) == len &&
> + !strncmp(model->name, cpu_type, len)) {
> + /* KVM is enabled and we're using this type, so it works. */
> + supported = true;
> + }
> + if (!supported) {
> + error_setg(errp, "We cannot guarantee the CPU type '%s' works "
> + "with KVM on this host", model->name);
> + return NULL;
> + }
> + }
> +
The above section can be slightly reduced and rearranged - preferably
moved to a separate function
-> get_cpu_model (...) ?
* You can check the 'host' model first and then validate the accelerator ->
if ( !strcmp(model->name, "host")
if (!kvm_enabled())
log_error & leave
else
goto cpu_class_by_name /*cpu_class_by_name moved after the
final model check @see below */
* the kvm_enabled section can be than slightly improved (dropping the
second compare against 'host')
if (kvm_enabled() && strcmp(model->name, "max") {
/*Validate the current_machine->cpu_type against the
model->name and report error case mismatch
/* otherwise just fall through */
}
* cpu_class_by_name moved here ...
> + if (model->props) {
MInor: the CPUModelInfo seems to have dedicated field for that
verification -> has_props
> + qdict_in = qobject_to(QDict, model->props);
> + if (!qdict_in) {
> + error_setg(errp, QERR_INVALID_PARAMETER_TYPE, "props", "dict");
> + return NULL;
> + }
> + }
> +
> + obj = object_new(object_class_get_name(oc));
> +
> + if (qdict_in) {
> + Visitor *visitor;
> + Error *err = NULL;
> +
> + visitor = qobject_input_visitor_new(model->props);
> + visit_start_struct(visitor, NULL, NULL, 0, &err);
> + if (err) {
> + object_unref(obj);
> + error_propagate(errp, err);
> + return NULL;
> + }
> +
> + i = 0;
> + while ((name = cpu_model_advertised_features[i++]) != NULL) {
> + if (qdict_get(qdict_in, name)) {
> + object_property_set(obj, visitor, name, &err);
> + if (err) {
> + break;
> + }
> + }
> + }
> +
> + if (!err) {
> + visit_check_struct(visitor, &err);
> + }
> + visit_end_struct(visitor, NULL);
> + visit_free(visitor);
> + if (err) {
> + object_unref(obj);
> + error_propagate(errp, err);
> + return NULL;
> + }
> + }
The both >> if (err) << blocks could be extracted and moved at the end
of the function
to mark a 'cleanup section' and both here and few lines before
(with the visit_start_struct failure) could use goto.
Easier to maintain and to make sure we make the proper cleanup in any case.
> +
> + expansion_info = g_new0(CpuModelExpansionInfo, 1);
> + expansion_info->model = g_malloc0(sizeof(*expansion_info->model));
> + expansion_info->model->name = g_strdup(model->name);
> +
> + qdict_out = qdict_new();
> +
> + i = 0;
> + while ((name = cpu_model_advertised_features[i++]) != NULL) {
> + ObjectProperty *prop = object_property_find(obj, name, NULL);
> + if (prop) {
> + Error *err = NULL;
> + QObject *value;
> +
> + assert(prop->get);
> + value = object_property_get_qobject(obj, name, &err);
> + assert(!err);
> +
> + qdict_put_obj(qdict_out, name, value);
> + }
> + }
> +
This could be merged with the first iteration over the features,
smth like:
while () {
if ((value = qdict_get(qdict_in, name))) {
object_property_set ...
if (!err)
qobject_ref(value) /* we have the weak reference */
else
break;
} else {
value = object_property_get_qobject()
}
if (value) qdict_put_object(qdict_out, name, value)
}
This way you iterate over the table once and you do not query
for the same property twice by getting the value from the qdict_in.
If the value is not acceptable we will fail either way so should be all good.
> + if (!qdict_size(qdict_out)) {
> + qobject_unref(qdict_out);
> + } else {
> + expansion_info->model->props = QOBJECT(qdict_out);
> + expansion_info->model->has_props = true;
> + }
> +
> + object_unref(obj);
> +
> + return expansion_info;
Mentioned earlier cleanup section:
cleanup:
object_unref(obj);
qobject_unref(qdict_out) ; /* if single loop is used */
error_propagate(errp,err);
return NULL;
> +}
> --
> 2.20.1
>
Hope I haven't missed anything.
What do you think ?
BR
Beata
> > Thanks,
> > drew
