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Date:   Fri, 11 Mar 2022 09:41:50 -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 09:39:13 -0800 Jakub Kicinski wrote:
> > 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.

Let me wrap the implementation in an ifdef, I guess that may be least
confusing and the linker error vs runtime warning is worth the cost.

> > > 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.