MFC 201131

introduce a local variable rte acting as a cache of ro->ro_rt
within ip_output, achieving (in random order of importance):
- a reduction of the number of 'r's in the source code;
- improved legibility;
- a reduction of 64 bytes in the .text
This commit is contained in:
Qing Li 2010-04-02 04:58:17 +00:00
parent 01104d862b
commit ca2d42b2a1

View File

@ -128,6 +128,7 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
struct in_ifaddr *ia = NULL;
int isbroadcast, sw_csum;
struct route iproute;
struct rtentry *rte; /* cache for ro->ro_rt */
struct in_addr odst;
#ifdef IPFIREWALL_FORWARD
struct m_tag *fwd_tag = NULL;
@ -205,18 +206,19 @@ again:
* The address family should also be checked in case of sharing the
* cache with IPv6.
*/
if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
rte = ro->ro_rt;
if (rte && ((rte->rt_flags & RTF_UP) == 0 ||
dst->sin_family != AF_INET ||
dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
if (!nortfree)
RTFREE(ro->ro_rt);
ro->ro_rt = (struct rtentry *)NULL;
RTFREE(rte);
rte = ro->ro_rt = (struct rtentry *)NULL;
ro->ro_lle = (struct llentry *)NULL;
}
#ifdef IPFIREWALL_FORWARD
if (ro->ro_rt == NULL && fwd_tag == NULL) {
if (rte == NULL && fwd_tag == NULL) {
#else
if (ro->ro_rt == NULL) {
if (rte == NULL) {
#endif
bzero(dst, sizeof(*dst));
dst->sin_family = AF_INET;
@ -266,7 +268,7 @@ again:
* as this is probably required in all cases for correct
* operation (as it is for ARP).
*/
if (ro->ro_rt == NULL)
if (rte == NULL) {
#ifdef RADIX_MPATH
rtalloc_mpath_fib(ro,
ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
@ -275,7 +277,9 @@ again:
in_rtalloc_ign(ro, 0,
inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m));
#endif
if (ro->ro_rt == NULL) {
rte = ro->ro_rt;
}
if (rte == NULL) {
#ifdef IPSEC
/*
* There is no route for this packet, but it is
@ -289,14 +293,14 @@ again:
error = EHOSTUNREACH;
goto bad;
}
ia = ifatoia(ro->ro_rt->rt_ifa);
ia = ifatoia(rte->rt_ifa);
ifa_ref(&ia->ia_ifa);
ifp = ro->ro_rt->rt_ifp;
ro->ro_rt->rt_rmx.rmx_pksent++;
if (ro->ro_rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
if (ro->ro_rt->rt_flags & RTF_HOST)
isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
ifp = rte->rt_ifp;
rte->rt_rmx.rmx_pksent++;
if (rte->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in *)rte->rt_gateway;
if (rte->rt_flags & RTF_HOST)
isbroadcast = (rte->rt_flags & RTF_BROADCAST);
else
isbroadcast = in_broadcast(dst->sin_addr, ifp);
}
@ -304,7 +308,7 @@ again:
* Calculate MTU. If we have a route that is up, use that,
* otherwise use the interface's MTU.
*/
if (ro->ro_rt != NULL && (ro->ro_rt->rt_flags & (RTF_UP|RTF_HOST))) {
if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST))) {
/*
* This case can happen if the user changed the MTU
* of an interface after enabling IP on it. Because
@ -312,9 +316,9 @@ again:
* them, there is no way for one to update all its
* routes when the MTU is changed.
*/
if (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)
ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
mtu = ro->ro_rt->rt_rmx.rmx_mtu;
if (rte->rt_rmx.rmx_mtu > ifp->if_mtu)
rte->rt_rmx.rmx_mtu = ifp->if_mtu;
mtu = rte->rt_rmx.rmx_mtu;
} else {
mtu = ifp->if_mtu;
}