Date: Wed, 22 Feb 2012 17:01:38 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>, linux-kernel@vger.kernel.org,
        mingo@elte.hu, dipankar@in.ibm.com, akpm@linux-foundation.org,
        mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com,
        tglx@linutronix.de, peterz@infradead.org, Valdis.Kletnieks@vt.edu,
        dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com,
        fweisbec@gmail.com, patches@linaro.org
Subject: Re: [PATCH 2/3 RFC paul/rcu/srcu] srcu: only increase the upper bit
 for srcu_read_lock()
Message-ID: <20120223010138.GQ2416@linux.vnet.ibm.com>
Reply-To: paulmck@linux.vnet.ibm.com
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 <20120221015037.GE2384@linux.vnet.ibm.com>
 <4F435966.9020106@cn.fujitsu.com>
 <20120221172442.GG2375@linux.vnet.ibm.com>
 <4F44B57C.3020104@cn.fujitsu.com>
 <20120222212056.GJ2416@linux.vnet.ibm.com>
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On Wed, Feb 22, 2012 at 04:39:15PM -0500, Steven Rostedt wrote:
> On Wed, 2012-02-22 at 13:26 -0800, Paul E. McKenney wrote:
> 
> > Make that without underflow -- one increment and 2^31+1 decrements would
> > in fact return the counter to its original value, but that would require
> > cramming more than two billion tasks into a 32-bit address space, which
> > I believe to be sufficiently unlikely.  (Famous last words...)
> 
> I'll just expect to see you as President of the United States, counting
> your money you won in the lottery, and being awarded a Nobel Prize for
> curing cancer.

Those possibilities also seem to me to be sufficiently unlikely.  ;-)

							Thanx, Paul

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