linux-kernel - Re: [PATCH 3/4] SunRPC: Use no_printk() for the null dprintk() and dfprintk()

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Message-ID: <30597.1380209743@warthog.procyon.org.uk>
Date:	Thu, 26 Sep 2013 16:35:43 +0100
From:	David Howells <dhowells@...hat.com>
To:	Joe Perches <joe@...ches.com>
Cc:	dhowells@...hat.com, bfields@...ldses.org,
	Trond.Myklebust@...app.com, olof@...om.net,
	linux-nfs@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4] SunRPC: Use no_printk() for the null dprintk() and dfprintk()

Joe Perches <joe@...ches.com> wrote:

> no_printk doesn't prevent any argument side-effects
> from being optimized away by the compiler.
> 
> ie:
> 	dprintk("%d", func())
> func is now always called when before it wasn't.

Yes, I know.  There are half a dozen places where this is the case.  Those
I've wrapped in ifdebug(FACILITY) { ... } in the code.  It's not the nicest,
but at least the compiler always gets to see everything, rather than bits of
it getting hidden by the preprocessor - which means the call points will be
less likely to bit rot over time.

David
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