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From: David Miller <davem@davemloft.net>
Subject: Re: [net-next 13/13] ixgbe: use per NUMA node lock for FCoE DDP
Date: Sat, 11 Jun 2011 19:00:39 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 11 Jun 2011 07:42:11 +0200

> This patch seems overkill to me, have you tried the more simple way I
> did in commit 79640a4ca6955e3ebdb7038508fa7a0cd7fa5527
> (net: add additional lock to qdisc to increase throughput )
> 
> (remember you must place ->busylock in a separate cache line, to not
> slow down the two cpus that have access to ->lock)
> 
> struct ixgbe_fcoe could probably be more carefuly reordered to lower
> false sharing
> 
> I kindly ask you guys provide actual perf numbers between
> 
> 1) before any patch
> 2) After your multilevel per numanode locks
> 3) A more simple way (my suggestion of adding a single 'busylock')

Jeff, please sort out these issues with Eric and resend your pull
request once things are resolved.

Thanks!