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Date: Wed, 30 Jul 2008 17:56:40 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Peter Zijlstra <peterz@infradead.org>,
       Thomas Gleixner <tglx@linutronix.de>,
       Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] ftrace: dump out ftrace buffers to console on panic
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On Wed, 30 Jul 2008 20:39:47 -0400 (EDT) Steven Rostedt <rostedt@goodmis.org> wrote:

> >
> >> +	__raw_spin_lock(&ftrace_dump_lock);
> >> +	dump_running = 0;
> >> +	__raw_spin_unlock(&ftrace_dump_lock);
> >> +
> >> + out:
> >> +	local_irq_restore(flags);
> >> +}
> >> +#endif /* CONFIG_FTRACE_DUMP_ON_OOPS */
> >
> > Do we really need a new config option for this?  Would it hurt too much
> > to make it unconditionally available?
> 
> I don't mind making it unconditionally available. I only added the config 
> option because I thought people would like to turn it off.
> 
> I'll resubmit with the above concerns fixed and without the config option.

Well..  my question about the config option was no more than a question
- I don't know the answer.

Although thinking about it, I guess that anyone who is really squeezy
on space just won't be enabling ftrace at all.  Is there any reason
other than size for disabling this new feature?