Re: [Qemu-devel] [PATCH v2 15/19] s390x: print CPU definitions in sorted order

[Cornelia Huck <cohuck@redhat.com>]

On Mon,  4 Sep 2017 17:43:12 +0200
David Hildenbrand <david@redhat.com> wrote:

> Other architectures provide nicely sorted lists, let's do it similarly on
> s390x.
> 
> While at it, clean up the code we have to touch either way.
> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  target/s390x/cpu_models.c | 63 ++++++++++++++++++++++++++++++-----------------
>  1 file changed, 41 insertions(+), 22 deletions(-)
> 
> diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
> index 8e20e7637b..092db34258 100644
> --- a/target/s390x/cpu_models.c
> +++ b/target/s390x/cpu_models.c
> @@ -270,41 +270,60 @@ const S390CPUDef *s390_find_cpu_def(uint16_t type, uint8_t gen, uint8_t ec_ga,
>      return last_compatible;
>  }
>  
> -struct S390PrintCpuListInfo {
> -    FILE *f;
> -    fprintf_function print;
> -};
> -
> -static void print_cpu_model_list(ObjectClass *klass, void *opaque)
> +static void s390_print_cpu_model_list_entry(gpointer data, gpointer user_data)
>  {
> -    struct S390PrintCpuListInfo *info = opaque;
> -    S390CPUClass *scc = S390_CPU_CLASS(klass);
> -    char *name = g_strdup(object_class_get_name(klass));
> -    const char *details = "";
> -
> -    if (scc->is_static) {
> -        details = "(static, migration-safe)";
> -    } else if (scc->is_migration_safe) {
> -        details = "(migration-safe)";
> -    }
> +    CPUListState *s = user_data;
> +    const S390CPUClass *scc = S390_CPU_CLASS((ObjectClass *)data);
> +    char *name = g_strdup(object_class_get_name((ObjectClass *)data));
>  
>      /* strip off the -s390-cpu */
>      g_strrstr(name, "-" TYPE_S390_CPU)[0] = 0;
> -    (*info->print)(info->f, "s390 %-15s %-35s %s\n", name, scc->desc,
> -                   details);
> +    (*s->cpu_fprintf)(s->file, "s390 %-15s %-35s (%smigration-safe)\n", name,
> +                      scc->desc, scc->is_static ? "static, " : "");

Hm, that now prints 's390 host' as 'migration safe'...

>      g_free(name);
>  }
>  
> +static gint s390_cpu_list_compare(gconstpointer a, gconstpointer b)
> +{
> +    const S390CPUClass *cc_a = S390_CPU_CLASS((ObjectClass *)a);
> +    const S390CPUClass *cc_b = S390_CPU_CLASS((ObjectClass *)b);
> +    const char *name_a = object_class_get_name((ObjectClass *)a);
> +    const char *name_b = object_class_get_name((ObjectClass *)b);
> +
> +    /* move qemu and host to the top of the list, qemu first, host second */
> +    if (name_a[0] == 'q') {
> +        return -1;
> +    } else if (name_b[0] == 'q') {
> +        return 1;
> +    } else if (name_a[0] == 'h') {
> +        return -1;
> +    } else if (name_b[0] == 'h') {
> +        return 1;
> +    }

Are we sure that there will never be models starting with q or h? But
we can worry about that later.

> +
> +    /* keep the same order we have in our table (sorted by release date) */
> +    if (cc_a->cpu_def != cc_b->cpu_def) {
> +        return cc_a->cpu_def - cc_b->cpu_def;
> +    }
> +
> +    /* exact same definition - list base model first */
> +    return cc_a->is_static ? -1 : 1;
> +}
> +
>  void s390_cpu_list(FILE *f, fprintf_function print)
>  {
> -    struct S390PrintCpuListInfo info = {
> -        .f = f,
> -        .print = print,
> +    CPUListState s = {
> +        .file = f,
> +        .cpu_fprintf = print,
>      };
>      S390FeatGroup group;
>      S390Feat feat;
> +    GSList *list;
>  
> -    object_class_foreach(print_cpu_model_list, TYPE_S390_CPU, false, &info);
> +    list = object_class_get_list(TYPE_S390_CPU, false);
> +    list = g_slist_sort(list, s390_cpu_list_compare);
> +    g_slist_foreach(list, s390_print_cpu_model_list_entry, &s);
> +    g_slist_free(list);
>  
>      (*print)(f, "\nRecognized feature flags:\n");
>      for (feat = 0; feat < S390_FEAT_MAX; feat++) {

Sorting looks good.