From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [Patch net-next] tcp_metrics: rearrange fields to avoid holes
Date: Tue, 30 Jul 2013 20:24:32 -0700
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Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Yuchung Cheng <ycheng@google.com>,
	Neal Cardwell <ncardwell@google.com>
To: Cong Wang <amwang@redhat.com>
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On Wed, 2013-07-31 at 11:13 +0800, Cong Wang wrote:
> On Tue, 2013-07-30 at 20:08 -0700, Eric Dumazet wrote:
> > 
> > Oh well, this patch is pure noise...
> > 
> > 
> 
> Mind to be specific?
> 
> I know saving 8 bytes is not interesting for you, but it is for me,
> since I need some room in struct tcp_metrics_block for union inet_addr.
> With this patch, I don't have to make struct tcp_metrics_block expand to
> 3 cachelines. :)

Do you see how this explanation is rather different than the one you
gave in the changelog ?

Its 3 lines, instead of all this pahole noise.

And it would be more logical to put the "unsigned long last_syn_loss" at
the beginning of the structure, instead after an array of 17 bytes.