Date: Sun, 22 Mar 2009 12:46:32 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: paulmck@linux.vnet.ibm.com
Cc: Eric Dumazet <dada1@cosmosbay.com>, dipankar@in.ibm.com,
       linux-input@vger.kernel.org, dmitry.torokhov@gmail.com,
       linux-kernel@vger.kernel.org
Subject: Re: Question about usage of RCU in the input layer
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On Sun, 22 Mar 2009 09:53:24 -0700
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:

> > > How many synchronize_rcu() calls are you seeing on the boot path?
> > 
> > I see 20 that hit the above code path (eg ones that wait) until
> > userspace starts.
> 
> So with well-behaved readers, the full sequence would be worth
> something like 50-60 milliseconds.

yeah it's about 10% if the total kernel boot time.. so it does start to
matter

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
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