Re: [PATCH tip/core/rcu 24/24] rcu: Conditionally compile RCU's eqs warnings

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From	Geert Uytterhoeven <geert@linux-m68k.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH tip/core/rcu 24/24] rcu: Conditionally compile RCU's eqs warnings
Date	Mon, 29 Jun 2015 23:00:02 +0200
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Hi Paul,

On Mon, Jun 29, 2015 at 10:55 PM, Paul E. McKenney
<paulmck@linux.vnet.ibm.com> wrote:
> On Mon, Jun 29, 2015 at 11:39:13AM +0200, Geert Uytterhoeven wrote:
>> On Wed, May 13, 2015 at 12:30 AM, Paul E. McKenney
>> <paulmck@linux.vnet.ibm.com> wrote:
>> > --- a/lib/Kconfig.debug
>> > +++ b/lib/Kconfig.debug
>> > @@ -1373,6 +1373,17 @@ config RCU_TRACE
>> >           Say Y here if you want to enable RCU tracing
>> >           Say N if you are unsure.
>> >
>> > +config RCU_EQS_DEBUG
>> > +       bool "Use this when adding any sort of NO_HZ support to your arch"
>>
>> This sounds a bit fuzzy. Can you please provide a better one-line description?
>> Thanks!
>
> So the point of this Kconfig option is to provide WARN_ON()s that catch
> bug such as telling RCU that a given CPU entered idle, but failing to
> tell RCU when that CPU later leaves idle.  So how about this?
>
> +       bool "Provide debugging asserts for adding NO_HZ support to an arch"

Much better, thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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Re: [PATCH tip/core/rcu 24/24] rcu: Conditionally compile RCU's eqs warnings Geert Uytterhoeven <geert@linux-m68k.org> - 2015-06-29 23:00 +0200

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