Subject: Re: [PATCH 1/2] powerpc, perf: Ignore separate BHRB privilege state filter request

From: Michael Neuling <[email-masked]>
Date: Tue, 28 May 2013 09:30:10 +1000

Anshuman Khandual <[email-masked]> wrote:

> On 05/22/2013 02:29 PM, Anshuman Khandual wrote:
> >>
> >> Your description from patch 0 should be here.
> > Does it sound better ?
> > 
> >>
> >>> -	if ((br_privilege != 7) && (br_privilege != 0))
> >>> -		return -1;
> >>> +
> >>> +	if (br_privilege)
> >>> +		pr_info("BHRB privilege state filter request %llx ignored\n",
> >>> +								br_privilege);
> >>
> >> Don't do that. Ignoring the br_privilege is either the right thing to do
> >> in which case we do it and print nothing,
> > 
> > 
> > I thought the informational print would at least make the user aware
> > of the fact that the separate filter request for BHRB went ignored.
> > Can we add this some where in the documentation ?
> 
> So, what we decide here ? We will just ignore any separate BHRB
> privilege state filter request without printing any informational
> event or warning ?

Printing it on the console is pointless.  No one will read it.  

If it's doing the filtering, then just drop the printk.  

	/* BHRB and regular PMU events share the same privilege state
	 * filter configuration. BHRB is always recorded along with a
	 * regular PMU event. As the privilege state filter is handled
	 * in the basic PMC configuration of the accompanying regular
	 * PMU event, we ignore any separate BHRB specific request.
	 */

That updated comment I think make it clear.  

So drop the printk and add the comment, and it's OK with me.

Mikey