Re: [PATCH v9 21/24] perf tools: Add support for the SPF perf event

From: David Rientjes
Date: Tue Apr 10 2018 - 02:47:57 EST


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.