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Date: Tue, 19 Apr 2011 13:07:25 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>, Avi Kivity <avi@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Rik van Riel <riel@redhat.com>,
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        Paul McKenney <paulmck@linux.vnet.ibm.com>,
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        Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH 15/20] mm: Convert i_mmap_lock to a mutex
Message-Id: <20110419130725.38cb638b.akpm@linux-foundation.org>
In-Reply-To: <20110401121726.037173835@chello.nl>
References: <20110401121258.211963744@chello.nl>
	<20110401121726.037173835@chello.nl>
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On Fri, 01 Apr 2011 14:13:13 +0200
Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> Straight fwd conversion of i_mmap_lock to a mutex

What effect does this have on kernel performance?

Workloads which take the lock at high frequency from multiple threads
should be tested.