RE: [PATCH 3/4] SunRPC: Use no_printk() for the null dprintk() and dfprintk()

Myklebust, Trond
2013-09-26T15:42:49Z

> -----Original Message-----
> From: David Howells [mailto:dhowells@redhat.com]
> Sent: Thursday, September 26, 2013 10:36 AM
> To: Joe Perches
> Cc: dhowells@redhat.com; bfields@fieldses.org; Myklebust, Trond;
> olof@lixom.net; linux-nfs@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 3/4] SunRPC: Use no_printk() for the null dprintk() and
> dfprintk()
>
> Joe Perches <joe@perches.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.

Your assumption is that RPC_DEBUG is disabled for most compiles. That is not the case.

Trond