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Date: Wed, 29 Apr 2009 07:43:59 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Andrew Morton <akpm@linux-foundation.org>
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: <20090429054359.GA6148@elte.hu>
References: <20090429044814.138790038@goodmis.org> <20090429045908.394874083@goodmis.org> <20090428222024.8db50539.akpm@linux-foundation.org>
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* 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.

> 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().

	Ingo