Subject: Re: [PATCH V2] powerpc/irq: Enable some more exceptions in /proc/interrupts interface

From: Anshuman Khandual <[email-masked]>
Date: Mon, 13 Jul 2015 10:54:21 +0530

On 07/10/2015 12:40 PM, Michael Neuling wrote:
> What's the performance impact of this?  If you run this test with --fp,
> --altivec or --vector what is the impact of adding this patch?
> 
> http://ozlabs.org/~anton/junkcode/context_switch2.c
> 
> eg 
>   ./context_switch2 --fp 0 0 

Please find the results here which looks similar with or without
the patch being applied.

(A) Floating point context switches (context_switch2 --fp 0 0)

Without the patch	With the patch
=================	==============
320216			323460
324596			318448
321206			316540
321308			316650
318904			316478

(B) AltiVec context switches (context_switch2 --altivec 0 0)

Without the patch	With the patch
=================	==============
352012			342028
345894			345156
354604			345534
354020			354714
353936			364814

(C) Vector context switches (context_switch2 --vector 0 0)

Without the patch	With the patch
=================	==============
354496			344296
361386			346822
361856			354932
344906			348722
343288			355014