Re: [PATCH] refcount: introduce refcount_is_one() helper function

From: Peter Zijlstra
Date: Thu Nov 18 2021 - 03:45:47 EST


On Thu, Nov 18, 2021 at 08:12:56AM +0000, yajun.deng@xxxxxxxxx wrote:
> November 18, 2021 3:42 PM, "Peter Zijlstra" <peterz@xxxxxxxxxxxxx> wrote:
>
> > On Thu, Nov 18, 2021 at 11:53:28AM +0800, Yajun Deng wrote:
> >
> >> There are many cases where it is necessary to determine if refcount is one,
> >> introduce refcount_is_one() helper function for these cases.
> >
> > Give me one that is not racy?
>
> The following determine refcount is one, 35 count.

Very good, now get me one that isn't broken :-)