linux-kernel - Re: [RFC] [PATCH 2.6.37-rc5-tip 4/20] 4: uprobes: Adding and remove a uprobe in a rb tree.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20110126084103.GE19725@linux.vnet.ibm.com>
Date:	Wed, 26 Jan 2011 14:11:03 +0530
From:	Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Ingo Molnar <mingo@...e.hu>, Steven Rostedt <rostedt@...dmis.org>,
	Arnaldo Carvalho de Melo <acme@...radead.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Christoph Hellwig <hch@...radead.org>,
	Andi Kleen <andi@...stfloor.org>,
	Oleg Nesterov <oleg@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>,
	SystemTap <systemtap@...rces.redhat.com>,
	Jim Keniston <jkenisto@...ux.vnet.ibm.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Ananth N Mavinakayanahalli <ananth@...ibm.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	"Paul E. McKenney" <paulmck@...ux.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.

* Peter Zijlstra <peterz@...radead.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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/