Re: [PATCH 07/17] net: convert sock.sk_refcnt from atomic_t to refcount_t

From: David Miller
Date: Sat Mar 18 2017 - 21:31:05 EST


From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Date: Sun, 19 Mar 2017 00:47:59 +0800

> Eric Dumazet <eric.dumazet@xxxxxxxxx> 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.

I totally agree as well, the refcount_t facility as-is is unacceptable
for networking.