Re: [Qemu-devel] [PATCH v11 12/12] netfilter: add multiqueue support

[Jason Wang <jasowang@redhat.com>]

On 09/16/2015 08:16 PM, Yang Hongyang wrote:
> From: Yang Hongyang <burnef@gmail.com>
>
> add multiqueue support, if there's multiqueue, we add multi netfilter
> objects, other netfilter objects is the child of the first added netfilter
> object. So when we delete a netfilter, the other netfilter objects we
> added will be automatically deleted.
>
> Signed-off-by: Yang Hongyang <burnef@gmail.com>
> ---
> v11: initial patch
> ---
>  net/filter.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
>  1 file changed, 79 insertions(+), 7 deletions(-)
>
> diff --git a/net/filter.c b/net/filter.c
> index aea619a..cc27528 100644
> --- a/net/filter.c
> +++ b/net/filter.c
> @@ -142,16 +142,25 @@ static void netfilter_finalize(Object *obj)
>      g_free(nf->name);
>  }
>  
> +static void proptb_free_val_func(gpointer data)
> +{
> +    g_free(data);
> +}
> +
>  static void netfilter_complete(UserCreatable *uc, Error **errp)
>  {
> -    NetFilterState *nf = NETFILTER(uc);
> +    NetFilterState *nf = NETFILTER(uc), *nfq = NULL;
>      NetClientState *ncs[MAX_QUEUE_NUM];
> -    NetFilterClass *nfc = NETFILTER_GET_CLASS(uc);
> -    int queues;
> +    NetFilterClass *nfc = NETFILTER_GET_CLASS(uc), *nfqc = NULL;
> +    int queues, i;
>      Error *local_err = NULL;
> -    char *str, *info;
> +    char *str, *info, *name;
>      ObjectProperty *prop;
>      StringOutputVisitor *ov;
> +    Object *obj = NULL;
> +    GHashTable *proptable = NULL;
> +    GHashTableIter iter;
> +    gpointer key, value;
>  
>      if (!nf->netdev_id) {
>          error_setg(errp, "Parameter 'netdev' is required");
> @@ -165,9 +174,6 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
>          error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "netdev",
>                     "a network backend id");
>          return;
> -    } else if (queues > 1) {
> -        error_setg(errp, "Multi queue is not supported");
> -        return;
>      }
>  
>      if (get_vhost_net(ncs[0])) {
> @@ -187,6 +193,17 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
>      }
>      QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
>  
> +    if (queues > 1) {
> +        /*
> +         * Store the properties of the filter except "type" property.
> +         * When there's multiqueue, we will create a new filter object
> +         * of the same type and same properties. this hashtable is used
> +         * to set newly created object properties.
> +         */
> +        proptable = g_hash_table_new_full(NULL, NULL, NULL,
> +                                          proptb_free_val_func);
> +    }

I'm thinking whether or not duplicate all the properties in each
netfilters is a good method. Maybe we can have a another ojbect with
array of pointers to NetFilter objects embedded? Another question is
whether or not we need to do this at this level. Maybe we can make the
necessary Netfilter multiqueue aware. E.g let buffer filter to have
multiqueue also? Then you may only need a single timer?

> +
>      /* generate info str */
>      QTAILQ_FOREACH(prop, &OBJECT(nf)->properties, node) {
>          if (!strcmp(prop->name, "type")) {
> @@ -199,9 +216,64 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
>          string_output_visitor_cleanup(ov);
>          info = g_strdup_printf(",%s=%s", prop->name, str);
>          g_strlcat(nf->info_str, info, sizeof(nf->info_str));
> +        if (queues > 1) {
> +            g_hash_table_insert(proptable, prop->name, g_strdup(str));
> +        }
>          g_free(str);
>          g_free(info);
>      }
> +
> +    for (i = 1; i < queues; i++) {
> +        obj = object_new(object_get_typename(OBJECT(nf)));
> +        /* set filter properties */
> +        nfq = NETFILTER(obj);
> +        nfq->name = g_strdup(nf->name);
> +        nfq->netdev = ncs[i];
> +        snprintf(nfq->info_str, sizeof(nfq->info_str), "%s", nf->info_str);
> +
> +        g_hash_table_iter_init(&iter, proptable);
> +        while (g_hash_table_iter_next(&iter, &key, &value)) {
> +            object_property_parse(obj, (char *)value, (char *)key, &local_err);
> +            if (local_err) {
> +                error_propagate(errp, local_err);
> +                goto out;
> +            }
> +        }
> +
> +        /* add other queue's filter object as the first object's child */
> +        name = g_strdup_printf("%s-queue-%d", nf->name, i);
> +        object_property_add_child(OBJECT(nf), name, obj, &local_err);
> +        g_free(name);
> +        if (local_err) {
> +            error_propagate(errp, local_err);
> +            goto out;
> +        }
> +
> +        /* setup filter */
> +        nfqc = NETFILTER_GET_CLASS(obj);
> +        if (nfqc->setup) {
> +            nfqc->setup(nfq, &local_err);
> +            if (local_err) {
> +                error_propagate(errp, local_err);
> +                goto out;
> +            }
> +        }
> +        QTAILQ_INSERT_TAIL(&nfq->netdev->filters, nfq, next);
> +        object_unref(obj);
> +    }
> +
> +    if (proptable) {
> +        g_hash_table_unref(proptable);
> +    }
> +    return;
> +
> +out:

We may leak objects here.

> +    if (proptable) {
> +        g_hash_table_unref(proptable);
> +    }
> +    if (obj) {
> +        object_unref(obj);
> +    }
>  }
>  
>  static void netfilter_class_init(ObjectClass *oc, void *data)

To reduce the review iterations, I suggest to drop the patch also.
Multiqueue support could be another series on top.

Thanks