Date: Sun, 19 Mar 2017 00:47:59 +0800
From: Herbert Xu <herbert@gondor.apana.org.au>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: elena.reshetova@intel.com, davem@davemloft.net, keescook@chromium.org,
        peterz@infradead.org, netdev@vger.kernel.org,
        bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        kuznet@ms2.inr.ac.ru, jmorris@namei.org, kaber@trash.net,
        stephen@networkplumber.org, ishkamiel@gmail.com, dwindsor@gmail.com,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 07/17] net: convert sock.sk_refcnt from atomic_t to
 refcount_t
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Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Fri, 2017-03-17 at 07:42 +0000, Reshetova, Elena wrote:
> 
>> Should we then first measure the actual numbers to understand what we
>> are talking here about? 
>> I would be glad to do it if you suggest what is the correct way to do
>> measurements here to actually reflect the real life use cases. 
> 
> How have these patches been tested in real life exactly ?
> 
> Can you quantify number of added cycles per TCP packet, where I expect
> we have maybe 20 atomic operations in all layers ...

I completely agree.  I think this thing needs to default to the
existing atomic_t behaviour.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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