Messages in this thread | | | Subject | Re: [PATCH] sched: Support current clocksource handling in fallback sched_clock(). | From | Daniel Walker <> | Date | Thu, 28 May 2009 09:52:27 -0700 |
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On Fri, 2009-05-29 at 01:40 +0900, Paul Mundt wrote: > On Thu, May 28, 2009 at 06:32:09PM +0200, Peter Zijlstra wrote: > > On Thu, 2009-05-28 at 09:13 -0700, Daniel Walker wrote: > > > On Thu, 2009-05-28 at 14:59 +0200, Peter Zijlstra wrote: > > > > CPU0 CPU1 > > > > > > > > clock = ACCESS_ONCE(sched_clocksource); > > > > > > > > unload module > > > > clocksource_unregister() > > > > sched_clocksource = jiffies > > > > unmap data/text > > > > > > > > cyc2ns(clock, clocksource_read(clock)) <--- fireworks > > > > > > > > > > > > > > Do any module based clocksources even exist right now? > > > clocksource_unregister only seems to be used 3 times.. > > > > Good point, it appears its not even exported. > > > > Thomas mentioned modules, I assumed. > > > The drivers/clocksource/ drivers in theory could be modular anyways. > Handling this transition properly is at least one less barrier to modular > clocksources, so I think it's progress regardless. I don't remember what > all of the other issues were though, John probably remembers.
I don't think it's an important case to consider right now .. clocksources are usually so integral to the system putting one in a module seems counterintuitive.
Daniel
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