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Date:   Fri, 11 Mar 2022 09:39:13 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Leon Romanovsky <leonro@nvidia.com>
Cc:     <idosch@nvidia.com>, <petrm@nvidia.com>,
        <simon.horman@corigine.com>, <netdev@vger.kernel.org>,
        <jiri@resnulli.us>
Subject: Re: [RFT net-next 1/6] devlink: expose instance locking and add
 locked port registering
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On Fri, 11 Mar 2022 18:57:35 +0200 Leon Romanovsky wrote:
> On Fri, Mar 11, 2022 at 08:26:11AM -0800, Jakub Kicinski wrote:
> > On Fri, 11 Mar 2022 18:09:36 +0200 Leon Romanovsky wrote:  
> > > What about this?  
> > 
> > Is it better?   
> 
> I think so. It doesn't create shadow dependency on LOCKDEP.
> In your variant, all users of this call will generate WARN
> in production systems that run without lockdep.

No, no, that function is mostly for rcu dereference checking.
The calls should be eliminated as dead code on production systems.

> So if you want the "eliminate" thing like you wrote in the comment,
> the ifdef is a common solution.

I think these days people try to use IS_ENABLED() whenever possible.

> > Can do it you prefer, but I'd lean towards a version
> > without an ifdef myself.  
> 
> So you need to add CONFIG_LOCKDEP dependency in devlink Kconfig.

I don't see why.