Re: [PATCH net-next-2.6] ipv6: Reduce timer events for addrconf_verify().

[David Miller <davem@davemloft.net>]

From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Date: Thu, 18 Mar 2010 18:01:11 +0900

> This patch reduces timer events while keeping accuracy by rounding
> our timer and/or batching several address validations in addrconf_verify().
> 
> addrconf_verify() is called at earliest timeout among interface addresses'
> timeouts, but at maximum ADDR_CHECK_FREQUENCY (120 secs).
> 
> In most cases, all of timeouts of interface addresses are long enough
> (e.g. several hours or days vs 2 minutes), this timer is usually called
> every ADDR_CHECK_FREQUENCY, and it is okay to be lazy.
> (Note this timer could be eliminated if all code paths which modifies
> variables related to timeouts call us manually, but it is another story.)
> 
> However, in other least but important cases, we try keeping accuracy.
> 
> When the real interface address timeout is coming, and the timeout
> is just before the rounded timeout, we accept some error.
> 
> When a timeout has been reached, we also try batching other several
> events in very near future.
> 
> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Applied.