On Fri, 20 Apr 2018, Peter Zijlstra wrote:
> On Wed, Apr 18, 2018 at 11:10:20AM -0400, Vince Weaver wrote:
> > On Tue, 17 Apr 2018, Jiri Olsa wrote:
> >
> > > On Mon, Apr 16, 2018 at 10:04:53PM +0000, Stephane Eranian wrote:
> > > > Hi,
> > > >
> > > > I am trying to understand what the exclude_idle event attribute is
> > > > supposed
> > > > to accomplish.
> > > > As per the definition in the header file:
> > > >
> > > > exclude_idle : 1, /* don't count when idle */
> > >
> > > AFAICS it's not implemented
> >
> > so just to be completely clear hear, we're saying that the "exclude_idle"
> > modifier has never done anything useful and still doesn't?
>
> AFAICT it works on Power and possibly ARM.
at least some ARMs are a bit more honest about it than x86
ivybridge:
Performance counter stats for '/bin/ls':
1,368,162 instructions
1,368,162 instructions:I
pi2/ARM cortex-A7
Performance counter stats for '/bin/ls':
1,910,083 instructions
<not supported> instructions:I
I'd fire up my Power8 machine to see but not sure it's worth the hassle
and/or having to get out the ear protection.
Vince
