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

From: Eric Dumazet
Date: Wed Mar 22 2017 - 10:55:00 EST


On Wed, 2017-03-22 at 15:33 +0100, Peter Zijlstra wrote:

>
> But I would feel a whole lot better about the entire thing if we could
> measure their impact. It would also give us good precedent to whack
> other potential users of _nocheck over the head with -- show numbers.

I wont be able to measure the impact on real workloads, our productions
kernels are based on 4.3 at this moment.

I guess someone could code a lib/test_refcount.c launching X threads
using either atomic_inc or refcount_inc() in a loop.

That would give a rough estimate of the refcount_t overhead among
various platforms.