[PATCH] powerpc/mm: Add trace point for tracking hash pte fault

[Michael Ellerman]

On Tue, 2015-01-20 at 17:05 +0530, Aneesh Kumar K.V wrote:
> This enables us to understand how many hash fault we are taking
> when running benchmarks.
> 
> For ex:
> -bash-4.2# ./perf stat -e  powerpc:hash_fault -e page-faults /tmp/ebizzy.ppc64 -S 30  -P -n 1000
> ...
> 
>  Performance counter stats for '/tmp/ebizzy.ppc64 -S 30 -P -n 1000':
> 
>        1,10,04,075      powerpc:hash_fault
>        1,10,03,429      page-faults
> 
>       30.865978991 seconds time elapsed

Looks good.

Can you attach some test results that show it's not hurting performance when
it's disabled.

cheers