Re: RCU_USER_QS traces.

[Frederic Weisbecker]

On Thu, Oct 04, 2012 at 10:41:06AM -0400, Dave Jones wrote:
>  > We have CONFIG_RCU_USER_QS that is a specific case. It's an intermediate state
>  > before we implement a true CONFIG_NO_HZ_FULL. But the option is useless on its
>  > own for users. Worse, it introduces a real overhead. OTOH we want it to be upstream
>  > to make the development of full tickless feature more incremental.
> 
> I couldn't resist trying it.. Did these get reported yet ?

Hi Dave,

Thanks for this report. I need to find the source of the issue.

If you don't mind, could you please apply the following patch? You'll also
need to enable:

- CONFIG_EVENT_TRACING and CONFIG_RCU_TRACE

And you also need this boot parameter:

- trace_event=rcu_dyntick

Thanks a lot!

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