Messages in this thread | | | Subject | Re: remove cpu hotplug bustification in cpufreq. | From | Arjan van de Ven <> | Date | Sun, 23 Jul 2006 10:29:40 +0200 |
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Hi,
> > Well, I just got Ashok's trial patches which turns the thing into a rwsem > > as I outlined earlier. > > Mark my words ;) > > > I'll try them out. If they don't work, we should just delete the lock and > > go totally back to square 1. > > rwsem conversion has the potential to merely hide the problem. Ingo, does > lockdep detect recursive down_read()?
lockdep detects and warns about those.
I think we're about equally skeptical about this; I'm extremely hesitant about any place in the kernel that uses rwsems for anything other than a performance tweak. I've ended up with a mental model of rwsems that basically comes down to "you need to be able to replace it with a mutex without breaking correctness". Now of course that model is somewhat of an oversimplification, but not by that much...
Greetings, Arjan van de Ven - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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