On Tue, 7 Apr 2015 17:46:40 -0300
Eduardo Habkost <ehabk...@redhat.com> wrote:
> This uses the feature name arrays to register "feat-*" QOM properties
> for feature flags. This simply adds the properties so they can be
> configured using -global, but doesn't change x86_cpu_parse_featurestr()
> to use them yet.
>
> Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
> ---
> target-i386/cpu.c | 98
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 98 insertions(+)
>
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index 099ed03..f29e55e 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -2883,12 +2883,103 @@ out:
> }
> }
>
> +typedef struct FeatureProperty {
> + FeatureWord word;
> + uint32_t mask;
> +} FeatureProperty;
> +
> +
> +static void x86_cpu_get_feature_prop(Object *obj,
> + struct Visitor *v,
> + void *opaque,
> + const char *name,
> + Error **errp)
> +{
> + X86CPU *cpu = X86_CPU(obj);
> + CPUX86State *env = &cpu->env;
> + FeatureProperty *fp = opaque;
> + bool value = (env->features[fp->word] & fp->mask) == fp->mask;
> + visit_type_bool(v, &value, name, errp);
> +}
> +
> +static void x86_cpu_set_feature_prop(Object *obj,
> + struct Visitor *v,
> + void *opaque,
> + const char *name,
> + Error **errp)
> +{
> + X86CPU *cpu = X86_CPU(obj);
> + CPUX86State *env = &cpu->env;
> + FeatureProperty *fp = opaque;
> + bool value;
> + visit_type_bool(v, &value, name, errp);
> + if (value) {
> + env->features[fp->word] |= fp->mask;
> + } else {
> + env->features[fp->word] &= ~fp->mask;
> + }
> +}
> +
> +/* Register a boolean feature-bits property.
> + * If mask has multiple bits, all must be set for the property to return
> true.
> + * The same property name can be registered multiple times to make it affect
> + * multiple bits in the same FeatureWord.
> + */
> +static void x86_cpu_register_feature_prop(X86CPU *cpu,
> + const char *prop_name,
> + FeatureWord w,
> + uint32_t mask)
> +{
> + FeatureProperty *fp;
> + ObjectProperty *op;
> + op = object_property_find(OBJECT(cpu), prop_name, NULL);
> + if (op) {
> + fp = op->opaque;
> + assert(fp->word == w);
> + fp->mask |= mask;
> + } else {
> + fp = g_new0(FeatureProperty, 1);
> + fp->word = w;
> + fp->mask = mask;
> + object_property_add(OBJECT(cpu), prop_name, "bool",
> + x86_cpu_get_feature_prop,
> + x86_cpu_set_feature_prop,
> + NULL, fp, &error_abort);
> + }
> +}
it would be better to create generic bit property and replace above code with it
something similar to object_property_add_uint32_ptr()
> +
> +static void x86_cpu_register_feature_bit_props(X86CPU *cpu,
> + FeatureWord w,
> + int bit)
> +{
> + int i;
> + char **names;
> + FeatureWordInfo *fi = &feature_word_info[w];
> +
> + if (!fi->feat_names) {
> + return;
> + }
> + if (!fi->feat_names[bit]) {
> + return;
> + }
> +
> + names = g_strsplit(fi->feat_names[bit], "|", 0);
> + for (i = 0; names[i]; i++) {
> + char *feat_name = names[i];
> + char *prop_name = g_strdup_printf("feat-%s", feat_name);
> + x86_cpu_register_feature_prop(cpu, prop_name, w, (1UL << bit));
it might be better instead of creating duplicate property to make an alias
