Messages in this thread | | | Date | Tue, 5 Jul 2011 08:24:05 -0400 | From | Don Zickus <> | Subject | Re: [PATCH -tip, final] perf, x86: Add hw_watchdog_set_attr() in a sake of nmi-watchdog on P4 |
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On Tue, Jul 05, 2011 at 01:44:37PM +0200, Ingo Molnar wrote: > > Probably I miss something and you mean something completely different? > > What i am missing is that you have not pointed out the *core problem* > you are fixing and it's not obvious from the changelog either!
Cyril,
I think you didn't explain the fact that without this patch if you enable nmi_watchdog, then the 'perf' tool doesn't work on a P4. This is bad for end users. It seems like with all the P4 register coupling an end user can run either the nmi_watchdog _or_ perf but not both.
For RHEL-6 this was bad because we like to enable the nmi_watchdog.
This patch does some magic and allows the end user to use the nmi_watchdog _and_ perf concurrently (a common expected behaviour).
I hope that clears things up Ingo.
Cheers, Don
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