[mpls-linux-devel] [RFC] Patch: Use generic internet flow cache for incoming label lookup

[Ramon C. <cas...@in...>]

James, All,


do you think this is worth the hassle and that there is indeed a
performance gain ? (I am not even sure if this is a good approach...)



#define MPLS_ENABLE_FLOW_CACHE


#ifdef MPLS_ENABLE_FLOW_CACHE

static void
mpls_mii_resolver (struct flowi *key, u16 family, u8 dir,
                void **objp, atomic_t **obj_refp)
{
        /* Look up the mii object */
        struct mpls_in_info* mii;

        read_lock   (&mpls_mii_lock);
        mii = radix_tree_lookup (&mpls_mii_tree, key->fl6_flowlabel);
        read_unlock (&mpls_mii_lock);

        /* Give the object address and its refcount. */
        *objp     =  mii;
        *obj_refp = (mii)? &mii->kobj.refcount : NULL;
}
#endif



struct mpls_in_info*
mpls_get_mii_by_label (
        struct mpls_push_data *mpr,
        mpls_label_t *label,
        int labelspace)
{
        struct mpls_in_info *mii = NULL;

#ifdef MPLS_ENABLE_FLOW_CACHE
        struct flowi in_flow;

        /* RCAS: We use fl6_flowlabel as the MII key */
        in_flow.fl6_flowlabel = mpls_label2key (labelspace,label);

        /* RCAS: Lookup flow in percpu flow cache  */
        mii = flow_cache_lookup(&in_flow, AF_MPLS, MPLS_IN,
mpls_mii_resolver);
        if (likely(mii)) {
                mpls_in_info_hold(mii);
                return mii;
        }

        /* If !mii it is either reserved or a bug. */
#endif
   /* handle the reserved label range */
        if (label->ml_type == MPLS_
.....



comments welcome

regards,
Ramon


// -------------------------------------------------------------------
// Ramon Casellas - GET/ENST/INFRES/RHD/A508 - cas...@in...