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Date: Tue, 6 Oct 2009 12:43:33 -0400 (EDT)
From: Christoph Lameter <cl@linux-foundation.org>
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To: nickpiggin@yahoo.com.au, Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
cc: akpm@linux-foundation.org, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org,
       "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, linux-mm@kvack.org
Subject: Re: [patch 4/4] vunmap: Fix racy use of rcu_head
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On Tue, 6 Oct 2009, Mathieu Desnoyers wrote:

> Simplest fix: directly kfree the data structure rather than doing it lazily.

The delay is necessary as far as I can tell for performance reasons. But
Nick was the last one fiddling around with the subsystem as far as I
remember. CCing him. May be he has a minute to think about a fix that
preserved performance.


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Date: Tue, 6 Oct 2009 12:43:33 -0400 (EDT)
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: [patch 4/4] vunmap: Fix racy use of rcu_head
In-Reply-To: <20091006144043.378971387@polymtl.ca>
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To: nickpiggin@yahoo.com.au, Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: akpm@linux-foundation.org, Ingo Molnar <mingo@elte.hu>, linux-kernel@vger.kernel.org, "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, linux-mm@kvack.org
List-ID: <linux-mm.kvack.org>

On Tue, 6 Oct 2009, Mathieu Desnoyers wrote:

> Simplest fix: directly kfree the data structure rather than doing it lazily.

The delay is necessary as far as I can tell for performance reasons. But
Nick was the last one fiddling around with the subsystem as far as I
remember. CCing him. May be he has a minute to think about a fix that
preserved performance.

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