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Date: Tue, 28 Apr 2009 22:55:41 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>, linux-kernel@vger.kernel.org,
       Frederic Weisbecker <fweisbec@gmail.com>
Subject: Re: [PATCH 5/5] ring-buffer: fix printk output
Message-Id: <20090428225541.9ca61a12.akpm@linux-foundation.org>
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On Wed, 29 Apr 2009 07:43:59 +0200 Ingo Molnar <mingo@elte.hu> wrote:

> 
> * Andrew Morton <akpm@linux-foundation.org> wrote:
> 
> > On Wed, 29 Apr 2009 00:48:19 -0400 Steven Rostedt <rostedt@goodmis.org> wrote:
> > 
> > > -	printk_once(KERN_WARNING "Tracing recursion: depth[%d]:"
> > > +	printk_once(KERN_WARNING "Tracing recursion: depth[%ld]:"
> > 
> > hrmph.  I didn't know that printk_once() existed, and I should 
> > have known.  I wonder how many other people don't know.
> 
> Was posted to linux-next@vger.kernel.org.

Well no wonder I didn't know about it.

> > Should it use unlikely()?
> 
> Not really. Any printk_once() usage site is an 'unlikely' branch 
> already in most cases. Double unlikely just spreads the instructions 
> needlessly. The condition that _leads_ to a printk_once() should be 
> an unlikely().
> 

OK.