From mboxrd@z Thu Jan  1 00:00:00 1970
From: Simon Kirby <sim@hostway.ca>
Subject: test
Date: Wed, 4 Nov 2009 12:27:16 -0800
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To: netdev@vger.kernel.org, Wensong Zhang <wensong@linux-vs.org>,
	Julian Anastasov <ja@ssi.bg>
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Hello!

I was noticing a significant amount of what seems/seemed to be
destination lists with multiple entries with the lblcr LVS algorithm. 
While tracking it down, I think I stumbled over a mistake.  In
ip_vs_lblcr_full_check(), it appears the time check logic is reversed:

        for (i=0, j=tbl->rover; i<IP_VS_LBLCR_TAB_SIZE; i++) {
                j = (j + 1) & IP_VS_LBLCR_TAB_MASK;

                write_lock(&svc->sched_lock);
                list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
                        if (time_after(en->lastuse+sysctl_ip_vs_lblcr_expiration,
                                       now))
                                continue;
                        
                        ip_vs_lblcr_free(en);
                        atomic_dec(&tbl->entries);
                }
                write_unlock(&svc->sched_lock);
        }

Shouldn't this be "time_before"?  It seems that it currently nukes all
recently-used entries every time this function is called, which seems to
be every 30 minutes, rather than removing the not-recently-used ones.

If my reading is correct, this patch should fix it.  Am I missing
something?

Cheers,

Simon-

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diff --git a/net/netfilter/ipvs/ip_vs_lblcr.c b/net/netfilter/ipvs/ip_vs_lblcr.c
index 715b57f..937743f 100644
--- a/net/netfilter/ipvs/ip_vs_lblcr.c
+++ b/net/netfilter/ipvs/ip_vs_lblcr.c
@@ -432,7 +432,7 @@ static inline void ip_vs_lblcr_full_check(struct ip_vs_service *svc)
 
 		write_lock(&svc->sched_lock);
 		list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
-			if (time_after(en->lastuse+sysctl_ip_vs_lblcr_expiration,
+			if (time_before(en->lastuse+sysctl_ip_vs_lblcr_expiration,
 				       now))
 				continue;
 

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