Re: [RFCv2 0/8] perf tool: Add new event group management

From: Jiri Olsa
Date: Mon Apr 16 2012 - 08:17:11 EST


On Sun, Apr 15, 2012 at 05:16:55PM +0200, Peter Zijlstra wrote:
> On Wed, 2012-04-04 at 23:16 +0200, Jiri Olsa wrote:
> > - added 'group=...' syntax to group events (patches 1-5).
>
> > - added 'group:1=...' syntax to specify which event to sample (leader)
>
> I'm still sad about not actually using {} for grouping. Esp. since you
> use ';' which needs escaping anyway:

yea, I realized we need ending separator after all ;)
so right we could use {} then..

so smth like:

'{cycles,faults}'
- anonymous group

'group1{cycles,faults}
- group with name 'group1'

'group1:1{cycles,faults}
- group with name 'group1' and modifier '1'

'group1{cycles,faults},{instructions,cache-misses},faults'
'{cycles,faults},group1:2{instructions,cache-misses},faults' ls
- group/event combinations


group: group_spec '{' events '}'
group_spec: name ':' mod | empty


also, any thoughts about the displaying question? ;)

> I'm looking on how to present this data in perf and it seems we need
> to reset all siblings once we read/store them (in kernel) to the
> leader sample.
>
> My current thinking is to store siblings' sum values for each
> hists entry of the sample (perf report count unit) .. and display
> them in similar way we display callchains: for each hists entry
> display the sum value for each sibling.
>
> Could you provide more of your world examples? Your expectations about
> presenting this..
>
> Maybe we want to make the reset optional, and do some do some other
> math with siblings' values..?

Not sure it could affect the syntax, but it'd be better to have
whole picture

thanks,
jirka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/