Re: [PATCH 1/1] vxlan: insert ipv6 macro
From: Jiri Benc <hidden>
Date: 2016-10-11 14:16:45
On Tue, 11 Oct 2016 16:23:31 +0800, zyjzyj2000@gmail.com wrote:
quoted hunk ↗ jump to hunk
--- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c@@ -2647,15 +2647,15 @@ static struct socket *vxlan_create_sock(struct net *net, bool ipv6, int err; memset(&udp_conf, 0, sizeof(udp_conf)); - +#if IS_ENABLED(CONFIG_IPV6) if (ipv6) { udp_conf.family = AF_INET6; udp_conf.use_udp6_rx_checksums = !(flags & VXLAN_F_UDP_ZERO_CSUM6_RX); udp_conf.ipv6_v6only = 1; - } else { + } else +#endif udp_conf.family = AF_INET; - }
Zhu Yanjun, before posting patches such as the previous ones or this one, please test whether they make any difference. In this case, try to compile the code with IPv6 disabled before and after this patch, disassemble and compare the results. You'll see that this patch is pointless. It's pretty obvious from the code but to be really sure, I've just quickly built the vxlan module with IPv6 disabled. And indeed, as expected, the compiler just inlined everything into vxlan_open. The whole chain vxlan_open -> vxlan_sock_add -> __vxlan_sock_add (note that there's only a single caller of __vxlan_sock_add with IPv6 disabled) -> vxlan_socket_create -> vxlan_create_sock is inlined. It also means the code in the "if (ipv6)" branch is completely eliminated by the compiler even without ugly #ifdefs. Jiri