From: Arnd Bergmann <arnd@arndb.de>
To: Jeff Layton <jeff.layton@primarydata.com>
Cc: trond.myklebust@primarydata.com, bfields@fieldses.org,
        linux-nfs@vger.kernel.org, Paul McKenney <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH 1/7] sunrpc: remove __rcu annotation from struct gss_cl_ctx->gc_gss_ctx
Date: Mon, 14 Jul 2014 17:29:16 +0200
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On Monday 14 July 2014 11:02:02 Jeff Layton wrote:
> On Mon, 14 Jul 2014 16:23:53 +0200
> Arnd Bergmann <arnd@arndb.de> wrote:
> 
> > On Sunday 13 July 2014 21:57:38 Jeff Layton wrote:
> > > 
> > > Commit 5b22216e11f7 (nfs: __rcu annotations) added a __rcu annotation to
> > > the gc_gss_ctx field. I see no rationale for adding that though, as that
> > > field does not seem to be managed via RCU at all.
> > > 
> > > Cc: Arnd Bergmann <arnd@arndb.de>
> > > Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
> > > Signed-off-by: Jeff Layton <jlayton@primarydata.com>
> > 
> > Unfortunately, it's been too long ago for me to remember what led to me
> > adding it. I also don't see a reason for it in today's code, but I don't
> > know if the code has changed, if I made a mistake then, or if it's actually
> > needed for some reason I don't see.
> > 
> 
> Darn, I was hoping you would remember... 
> 
> I don't think the code that manipulates this field has changed
> substantially since then, but I'm far from certain either. This field
> does live in a structure that is RCU managed, so maybe that was part of
> the rationale?
> 
> In any case, we're just removing the annotation here so this shouldn't
> materially harm anything, AFAICT.
> 

All the annotations I did were the results of building with sparse and
looking at the warnings. If you see fewer warnings after your patch
than before, than it's moving into the right direction ;-)

	Arnd