Re: [PATCH] IPv6: Refine IPv6 Address Validation Timer
flat view
From: YOSHIFUJI Hideaki / 吉藤英明 <hidden>
Date: 2002-09-27 15:11:29
Also in:
lkml
In article [ref] (at Fri, 27 Sep 2002 02:25:15 -0700 (PDT)), "David S. Miller" [off-list ref] says:
@@ -1626,24 +1635,32 @@
for (ifp=inet6_addr_lst[i]; ifp; ifp=ifp->lst_next) {
unsigned long age;
- if (ifp->flags & IFA_F_PERMANENT)
+ spin_lock(&ifp->lock);
+ if (ifp->flags & IFA_F_PERMANENT) {
+ spin_unlock(&ifp->lock);
continue;
+ }
This is completely unnecessary. Nobody modifies the
IFA_F_PERMANENT flag after the addr entry has been added
to the hash table and this runs under the addrconf hash
lock already.Thanks for comment. So, is this reasonable? Index: net/ipv6/addrconf.c =================================================================== RCS file: /cvsroot/usagi/usagi-backport/linux24/net/ipv6/addrconf.c,v retrieving revision 1.1.1.1 retrieving revision 1.1.1.1.4.4 diff -u -r1.1.1.1 -r1.1.1.1.4.4
--- net/ipv6/addrconf.c 2002/08/20 09:47:02 1.1.1.1
+++ net/ipv6/addrconf.c 2002/09/27 15:02:57 1.1.1.1.4.4@@ -26,6 +26,8 @@ * packets. * yoshfuji@USAGI : Fixed interval between DAD * packets. + * YOSHIFUJI Hideaki @USAGI : improved accuracy of + * address validation timer. */ #include <linux/config.h>
@@ -93,6 +95,7 @@ void addrconf_verify(unsigned long); static struct timer_list addr_chk_timer = { function: addrconf_verify }; +static spinlock_t addrconf_verify_lock = SPIN_LOCK_UNLOCKED; static int addrconf_ifdown(struct net_device *dev, int how);
@@ -1616,9 +1619,15 @@ void addrconf_verify(unsigned long foo) { struct inet6_ifaddr *ifp; - unsigned long now = jiffies; + unsigned long now, next; int i; + spin_lock_bh(&addrconf_verify_lock); + now = jiffies; + next = now + ADDR_CHECK_FREQUENCY; + + del_timer(&addr_chk_timer); + for (i=0; i < IN6_ADDR_HSIZE; i++) { restart:
@@ -1629,21 +1638,27 @@ if (ifp->flags & IFA_F_PERMANENT) continue; + spin_lock(&ifp->lock); age = (now - ifp->tstamp) / HZ; - if (age > ifp->valid_lft) { + if (age >= ifp->valid_lft) { + spin_unlock(&ifp->lock); in6_ifa_hold(ifp); write_unlock(&addrconf_hash_lock); ipv6_del_addr(ifp); goto restart; - } else if (age > ifp->prefered_lft) { + } else if (age >= ifp->prefered_lft) { + /* jiffies - ifp->tsamp > age >= ifp->prefered_lft */ int deprecate = 0; - spin_lock(&ifp->lock); if (!(ifp->flags&IFA_F_DEPRECATED)) { deprecate = 1; ifp->flags |= IFA_F_DEPRECATED; } + + if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)) + next = ifp->tstamp + ifp->valid_lft * HZ; + spin_unlock(&ifp->lock); if (deprecate) {
@@ -1654,12 +1669,24 @@ in6_ifa_put(ifp); goto restart; } + } else { + /* ifp->prefered_lft <= ifp->valid_lft */ + if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next)) + next = ifp->tstamp + ifp->prefered_lft * HZ; + spin_unlock(&ifp->lock); } } write_unlock(&addrconf_hash_lock); } - mod_timer(&addr_chk_timer, jiffies + ADDR_CHECK_FREQUENCY); + if (time_before(now + HZ/2, jiffies)) { + ADBG((KERN_WARNING + "addrconf_verify(): too slow; jiffies - now = %ld\n", + (long)jiffies - (long)now)); + } + addr_chk_timer.expires = time_before(next, jiffies + HZ) ? jiffies + HZ : next; + add_timer(&addr_chk_timer); + spin_unlock_bh(&addrconf_verify_lock); } static int
@@ -2033,8 +2060,7 @@ proc_net_create("if_inet6", 0, iface_proc_info); #endif - addr_chk_timer.expires = jiffies + ADDR_CHECK_FREQUENCY; - add_timer(&addr_chk_timer); + addrconf_verify(0); rtnetlink_links[PF_INET6] = inet6_rtnetlink_table; #ifdef CONFIG_SYSCTL addrconf_sysctl.sysctl_header =