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From: justin.skists@juzza.co.uk (Justin Skists)
To: kernelnewbies@lists.kernelnewbies.org
Subject: policy on externs
Date: Sat, 2 Jun 2018 18:43:31 +0100	[thread overview]
Message-ID: <20180602174331.GA13913@tanglefoot> (raw)
In-Reply-To: <20180602173346.GA21838@kroah.com>

On Sat, Jun 02, 2018 at 07:33:46PM +0200, Greg KH wrote:
> On Sat, Jun 02, 2018 at 05:23:20PM +0100, Justin Skists wrote:
> > Hi,
> > 
> > What is the kernel policy on using "extern" to share variables between
> > source files in a module?
> > 
> > I've been looking at one subsystem in staging [that shares variables quite a
> > bit] to becoming familar with it, and seeing if I can help do some work on it
> > in my free time.
> > 
> > Personally I prefer to see them eradicated (they polute the namespace), and
> > store such variables in a context structure that is passed around. But I don't
> > see any reference about it in the coding style, and I am not one to
> > code-churn just because it's not my personal style! :)
> 
> context structures are almost always best, as they can be tied to the
> hardware device, not the module itself.  So yes, if they can be
> eradicated, please do so.

OK, Greg. I'll have another look at it, then.

> What driver are you looking at?

I have been looking at the speakup subsystem.


Thanks,
Justin.

      reply	other threads:[~2018-06-02 17:43 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-02 16:23 policy on externs Justin Skists
2018-06-02 17:33 ` Greg KH
2018-06-02 17:43   ` Justin Skists [this message]

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