From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [net-next-2.6 PATCH v7 2/7 RFC] TCPCT part 1b: generate
 Responder Cookie secret
Date: Fri, 20 Nov 2009 12:51:26 -0800 (PST)
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From: Andi Kleen <andi@firstfloor.org>
Date: Fri, 20 Nov 2009 21:47:17 +0100

> David Miller <davem@davemloft.net> writes:
> 
>> From: William Allen Simpson <william.allen.simpson@gmail.com>
>> Date: Fri, 20 Nov 2009 09:23:21 -0500
>>
>>> +static DEFINE_SPINLOCK(tcp_secret_locker);
>>
>> So connection creation scalability will be limited now because
>> we'll always have to go through this centralized spinlock even
>> for independent listening sockets, right?
> 
> I was about to complain about the same thing in a earlier version
> of this patch kit, but then I noticed the spin lock aquiring 
> is guarded by
> 
> if (unlikely(time_after_eq(jiffy, tcp_secret_generating->expires))) {
> 
> which presumably makes it rare enough?

Works for me.