Re: [PATCH 4/6] perf kmem: Analyze page allocator events also

Namhyung Kim
2015-03-12T15:12:32Z

Hi Jiri,

On Thu, Mar 12, 2015 at 12:01:27PM +0100, Jiri Olsa wrote:
> On Thu, Mar 12, 2015 at 04:32:49PM +0900, Namhyung Kim wrote:
>
> SNIP
>
> > +static int parse_slab_opt(const struct option *opt __maybe_unused,
> > + const char *arg __maybe_unused,
> > + int unset __maybe_unused)
> > +{
> > + kmem_slab = (kmem_page + 1);
> > + return 0;
> > +}
> > +
> > +static int parse_page_opt(const struct option *opt __maybe_unused,
> > + const char *arg __maybe_unused,
> > + int unset __maybe_unused)
> > +{
> > + kmem_page = (kmem_slab + 1);
> > + return 0;
> > +}
>
> hum, just curious.. why not just assign 1, I'm missing the magic ;-)

Well, basically I just followed the existing convention. :)

Anyway it controls the effect of -s/--sort option. The single -s
option will be used to set sort keys for both of --alloc and --caller
stat. So it needs to known currently selected mode at option parsing
time. I extended it to page/slab selection also.

For example,

# perf kmem --page --alloc -s bytes --slab --caller -s hit

The first -s option will set sort keys for page/alloc stat and the
second -s option will set sort keys for slab/caller stat. So the -s
option should be preceded by at least one of the mode selection
options (i.e. --page/slab/alloc/caller). I'll add it to the man page
also.

Thanks,
Namhyung