+ /*
+ * We need a good default value for the xfrm6 gc threshold.
+ * In ipv4 we set it to the route hash table size * 8, which
+ * is half the size of the maximaum route cache for ipv4. It
+ * would be good to do the same thing for v6, except the table is
+ * constructed differently here. Here each table for a net namespace
+ * can have FIB_TABLE_HASHSZ entries, so lets go with the same
+ * computation that we used for ipv4 here. Also, lets keep the initial
+ * gc_thresh to a minimum of 1024, since, the ipv6 route cache defaults
+ * to that as a minimum as well
+ */
+ gc_thresh = FIB6_TABLE_HASHSZ * 8;
+ xfrm6_dst_ops.gc_thresh = (gc_thresh < 1024) ? 1024 : gc_thresh;
+