RE: timer expiry check at icmp.c in ipv6

Dear Eric,
    Can you please explain it into bit further. Actually what I want to know is how the preferred lifetime value of a router advertisement is processed?, Where it is stored? and while sending the ICMP_REPLY how that preferred lifetime value considered before actually sending the packet? I cannot able to find the relation between icmpv6_echo_reply and fib6_run_gc(). I am very new to kernel source. Kindly help me.

thank you.
________________________________________
From: netdev-owner@vger.kernel.org [netdev-owner@vger.kernel.org] on behalf of Eric Dumazet [eric.dumazet@gmail.com]
Sent: Monday, July 16, 2012 8:03 PM
To: BALAKUMARAN KANNAN
Cc: netdev@vger.kernel.org
Subject: Re: timer expiry check at icmp.c in ipv6

On Mon, 2012-07-16 at 13:44 +0000, BALAKUMARAN KANNAN wrote:

Dear all,

In kernel-3.0.26 code net/ipv6/icmp.c, while sending ICMP reply where
it checks for the timer expiry. It should check the value given by a
router advertisement. I think the expiry value is stored in
rt->rt6_expires in ndisc.c (line no: 1284). Then while sending an ICMP
reply, it should check with the expiry timer right? Where that check
is happening? Please somebody explain me.

Thank you.

Its probably done in net/ipv6/ip6_fib.c

fib6_gc_timer_cb() -> fib6_run_gc()

Every 30 seconds.

(you can change /proc/sys/net/ipv6/route/gc_interval )