Re: [Qemu-devel] [PATCH V5 01/12] NUMA: add NumaOptions, NumaNodeOptions and NumaMemOptions

[Laszlo Ersek]

On 07/17/13 16:44, Paolo Bonzini wrote:
> Il 17/07/2013 16:33, Laszlo Ersek ha scritto:
>>>>>> opts-visitor can handle lists of simple scalar types. Ie. it can do
>>>>>> -numa node,nodeid=3,cpus=3-4,cpus=9-10. It can't save the parsing of
>>>>>> intervals (eg. 3-4).
>>>>
>>>> Saving the parsing of intervals is not necessary for this use case.  So
>>>> if we can make it '*cpus':['int'], we should.
>>>>
>>>> But is it the opts-visitor "can handle" lists of integers, or does code
>>>> have to be written?  If the latter, can you whip up a prototype?
>> No extra code needs to be written. The current use case is
>> NetdevUserOptions.{dnssearch,hostfwd,guestfwd}; see commit 094f15c5, and
>> (by Klaus Stengel) commit 63d2960b.
> 
> This is to handle lists, but want about converting
> 
>   cpus=3-4,cpus=9-10
> 
> to
> 
>   'cpus': [3,4,9,10]

Oh, that. :) That does need extra code. Something along the lines of:

(a), in the JSON, reuse the existing String wrapper type, and make
"cpus" an optional list of String[s]:

{ 'type': 'NumaNodeOptions',
  'data': {
   '*nodeid':           'uint16',
   '*cpus':             ['String'] }}

(b) in the code, traverse the StringList like net_init_slirp_configs()
or slirp_dnssearch() does. Parse each element as an interval, set bit
ranges / report errors.

    static int numa_node_parse_cpu_range(int nodeid,
                                         const char *cpu_range)
    {
        /* what numa_node_parse_cpus() does in 02/12 */
    }

    static int numa_node_parse(const NumaNodeOptions *opts)
    {
        const StringList *cpu_range;

        /* not sure how to handle the (!opts->has_nodeid) case; let's
         * assume we have a nodeid here */

        if (opts->nodeid >= MAX_NODES) {
            fprintf(stderr,
                    "NUMA nodeid %d reaches / exceeds maximum %d\n",
                    opts->nodeid, MAX_NODES);
            return -1;
        }

        for (cpu_range = opts->cpus;
             cpu_range != NULL;
             cpu_range = cpu_range->next) {
            int ret;

            ret = numa_node_parse_cpu_range(opts->nodeid,
                                            cpu_range->value->str);
            if (ret < 0) {
                return ret;
            }
        }
        return 0;
    }

Did you mean something like this by prototype?

Thanks,
Laszlo