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Subject: Re: [RFC] [PATCH 2.6.37-rc5-tip 4/20]  4: uprobes: Adding and
 remove a uprobe in a rb tree.
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
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Date: Tue, 25 Jan 2011 13:15:42 +0100
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On Thu, 2010-12-16 at 15:28 +0530, Srikar Dronamraju wrote:
> +/* Should be called lock-less */
> +static void put_uprobe(struct uprobe *uprobe)
> +{
> +       if (atomic_dec_and_test(&uprobe->ref))
> +               kfree(uprobe);
> +} 

Since this instantly frees the uprobe once ref hits 0, the
atomic_inc_not_zero() in find_uprobe() doesn't really make sense does
it?