Re: [PATCH 2/3 -tip] perf_counter tools: Add support to set of multiple events in one shot

Ingo Molnar
2009-06-28T13:30:13Z

* Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:

> On Sat, 2009-06-27 at 18:38 +0200, Ingo Molnar wrote:
> > * Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:
> >
> > > Add support for HARDWARE and SOFTWARE events :
> > > perf stat -e all-sw-events
> > > perf stat -e sw-events
> > > perf stat -e all-hw-events
> > > perf stat -e hw-events
> >
> > > +static struct event_type_symbol event_type_symbols[] = {
> > > + [PERF_TYPE_HARDWARE] = { "hw-events", "all-hw-events", },
> > > + [PERF_TYPE_SOFTWARE] = { "sw-events", "all-sw-events", },
> >
> > Hm, this really just special-cases and open-codes these. The better
> > solution is what i suggested in my review of your prior patches:
> > regex pattern matching.
> >
>
> parse_events() is responsible to parse events for 'perf stat -e'
> and it is parsing by parse_event_symbol()
>
> If you want to use regex pattern matching then either we should
> make some another option or if we need to rewrite
> parse_event_symbol to use regex pattern matching which will be
> applicable to all the events.

As i mentioned it before, i think the most intuitive solution is to
extend the --event syntax with regex patterns. No new option - just
richer -e syntax.

We could have this syntax:

hw-cpu-cycles
hw-instructions
hw-cache-references
hw-cache-misses
hw-branch-instructions
hw-branch-misses
hw-bus-cycles

sw-cpu-clock
sw-task-clock
sw-page-faults
sw-minor-faults
sw-major-faults
sw-context-switches
sw-cpu-migrations

regex patterns like:

hw-*
sw-*
*

the first one would select all hardware events - the second all
software events - the third all events in general. But other regex
patterns make sense too, like:

*branch*
*cache*
*fault*

And as the number of generic events increases, so will regex
patterns become more and more useful.

Ingo