From 602582ca7a159622aebc5e643f6577fe8f0d6a41 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Sun, 19 Jan 2014 21:58:19 +0100 Subject: [PATCH] ipv6: optimize link local address search ipv6_link_dev_addr sorts newly added addresses by scope in ifp->addr_list. Smaller scope addresses are added to the tail of the list. Use this fact to iterate in reverse over addr_list and break out as soon as a higher scoped one showes up, so we can spare some cycles on machines with lot's of addresses. The ordering of the addresses is not relevant and we are more likely to get the eui64 generated address with this change anyway. Suggested-by: Brian Haley Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index f91e107d5f88..31bdedc32bdd 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -1437,7 +1437,9 @@ int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr, struct inet6_ifaddr *ifp; int err = -EADDRNOTAVAIL; - list_for_each_entry(ifp, &idev->addr_list, if_list) { + list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) { + if (ifp->scope > IFA_LINK) + break; if (ifp->scope == IFA_LINK && !(ifp->flags & banned_flags)) { *addr = ifp->addr; @@ -1858,7 +1860,9 @@ static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev) struct inet6_ifaddr *ifp; read_lock_bh(&idev->lock); - list_for_each_entry(ifp, &idev->addr_list, if_list) { + list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) { + if (ifp->scope > IFA_LINK) + break; if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) { memcpy(eui, ifp->addr.s6_addr+8, 8); err = 0; @@ -3239,7 +3243,9 @@ static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp) struct inet6_ifaddr *ifpiter; struct inet6_dev *idev = ifp->idev; - list_for_each_entry(ifpiter, &idev->addr_list, if_list) { + list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) { + if (ifpiter->scope > IFA_LINK) + break; if (ifp != ifpiter && ifpiter->scope == IFA_LINK && (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE| IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) == -- 2.20.1