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Date: Mon, 25 May 2009 10:08:34 +1000
From: Paul Mackerras <paulus@samba.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>, Corey Ashford <cjashfor@linux.vnet.ibm.com>,
       linux-kernel@vger.kernel.org,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       John Kacur <jkacur@redhat.com>
Subject: Re: [PATCH 1/7] perf_counter: fix dynamic irq_period logging
In-Reply-To: <20090523163012.476197912@chello.nl>
References: <20090523162854.599719825@chello.nl>
	<20090523163012.476197912@chello.nl>
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Peter Zijlstra writes:

> We call perf_adjust_freq() from perf_counter_task_tick() which is is called
> under the rq->lock causing lock recursion.

What was the lock recursion?  I see perf_adjust_freq taking ctx->lock,
but we were careful not to take any rq->lock within a ctx->lock, at
least in the past.

Paul.