After commit 
ca065d0cf80f ("udp: no longer use SLAB_DESTROY_BY_RCU")
we do not need this special allocation mode anymore, even if it is
harmless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
        .sysctl_wmem       = &sysctl_udp_wmem_min,
        .sysctl_rmem       = &sysctl_udp_rmem_min,
        .obj_size          = sizeof(struct udp_sock),
-       .slab_flags        = SLAB_DESTROY_BY_RCU,
        .h.udp_table       = &udp_table,
 #ifdef CONFIG_COMPAT
        .compat_setsockopt = compat_udp_setsockopt,
 
        .unhash            = udp_lib_unhash,
        .get_port          = udp_v4_get_port,
        .obj_size          = sizeof(struct udp_sock),
-       .slab_flags        = SLAB_DESTROY_BY_RCU,
        .h.udp_table       = &udplite_table,
 #ifdef CONFIG_COMPAT
        .compat_setsockopt = compat_udp_setsockopt,
 
        .sysctl_wmem       = &sysctl_udp_wmem_min,
        .sysctl_rmem       = &sysctl_udp_rmem_min,
        .obj_size          = sizeof(struct udp6_sock),
-       .slab_flags        = SLAB_DESTROY_BY_RCU,
        .h.udp_table       = &udp_table,
 #ifdef CONFIG_COMPAT
        .compat_setsockopt = compat_udpv6_setsockopt,
 
        .unhash            = udp_lib_unhash,
        .get_port          = udp_v6_get_port,
        .obj_size          = sizeof(struct udp6_sock),
-       .slab_flags        = SLAB_DESTROY_BY_RCU,
        .h.udp_table       = &udplite_table,
 #ifdef CONFIG_COMPAT
        .compat_setsockopt = compat_udpv6_setsockopt,