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Date:   Mon, 9 Apr 2018 23:47:48 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     Andi Kleen <ak@linux.intel.com>
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Subject: Re: [PATCH v9 21/24] perf tools: Add support for the SPF perf
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On Mon, 26 Mar 2018, Andi Kleen wrote:

> > Aside: should there be a new spec_flt field for struct task_struct that 
> > complements maj_flt and min_flt and be exported through /proc/pid/stat?
> 
> No. task_struct is already too bloated. If you need per process tracking 
> you can always get it through trace points.
> 

Hi Andi,

We have

	count_vm_event(PGFAULT);
	count_memcg_event_mm(vma->vm_mm, PGFAULT);

in handle_mm_fault() but not counterpart for spf.  I think it would be 
helpful to be able to determine how much faulting can be done 
speculatively if there is no per-process tracking without tracing.