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Date: Wed, 26 Jan 2011 14:11:03 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Andrew Morton <akpm@linux-foundation.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [RFC] [PATCH 2.6.37-rc5-tip 4/20]  4: uprobes: Adding and
 remove a uprobe in a rb tree.
Message-ID: <20110126084103.GE19725@linux.vnet.ibm.com>
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
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* Peter Zijlstra <peterz@infradead.org> [2011-01-25 13:15:42]:

> 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?

Okay, I can move the atomic_inc_not_zero() in find_uprobe() to
atomic_inc().

Do you see any side-effects of using atomic_inc_not_zero?

-- 
Thanks and Regards
Srikar