Re: [PATCH] perf/x86/intel: restrict period on Nehalem

[Peter Zijlstra]

On Mon, Aug 19, 2019 at 07:13:31PM -0400, Josh Hunt wrote:
> We see our Nehalem machines reporting 'perfevents: irq loop stuck!' in
> some cases when using perf:
> 
> perfevents: irq loop stuck!

> I found that a period limit of 32 was the lowest I could set it to without
> the problem reoccurring. The idea for the patch and approach to find the
> target value were suggested by Ingo and Thomas.
> 
> Signed-off-by: Josh Hunt <johunt@xxxxxxxxxx>
> Reported-by: Bhupesh Purandare <bpuranda@xxxxxxxxxx>
> Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx>
> Link: https://lore.kernel.org/lkml/20150501070226.GB18957@xxxxxxxxx/
> Link: https://lore.kernel.org/lkml/alpine.DEB.2.21.1908122133310.7324@xxxxxxxxxxxxxxxxxxxxxxx/

Thanks!