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Date:   Tue, 9 Oct 2018 16:58:18 +0100
From:   Will Deacon <will.deacon@arm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Lukasz Luba <l.luba@partner.samsung.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        b.zolnierkie@samsung.com, mingo@redhat.com, corbet@lwn.net
Subject: Re: [PATCH] Doc: lockdep: add information about performance impact
Message-ID: <20181009155818.GD9259@arm.com>
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On Tue, Oct 09, 2018 at 05:43:59PM +0200, Peter Zijlstra wrote:
> On Tue, Oct 09, 2018 at 05:39:27PM +0200, Lukasz Luba wrote:
> > This patch add some warning related to performance drop.
> > It should be mentioned that this is not for free
> > and the platfrom resources (cache, bus interconnect, etc.)
> > will be used more frequently.
> 
> To me this reads a bit like: water is wet.
> 
> Is this really needed?

I don't think so -- this is a debug option under "kernel hacking". Surely
the perf hit comes with the territory.

Will