Messages in this thread | | | Date | Sun, 22 Mar 2009 15:44:33 -0700 | From | Arjan van de Ven <> | Subject | Re: Question about usage of RCU in the input layer |
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On Sun, 22 Mar 2009 13:52:12 -0700 "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:
> On Sun, Mar 22, 2009 at 12:46:32PM -0700, Arjan van de Ven wrote: > > 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 > > Half-second boot, eh? That would indeed be impressive.
half a second until calling init.. that's what I have today (with all drivers built in).. nothing really special needed for it (well a few small patches that are pending for 2.6.30 ;-)
-- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org
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