Re: [PATCH 2/2] perf tools: Remove extra list_del_init calls in list reset

[Jiri Olsa]

On Thu, Jun 01, 2017 at 10:02:26AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, Jun 01, 2017 at 01:17:44PM +0200, Jiri Olsa escreveu:
> > We only needs to remove the format from the currently
> > iterated list. The other removals/inits are superfluous
> > because we free the format in any case.
> > 
> > Link: http://lkml.kernel.org/n/tip-8umo89ntt3kawmfwsivav43t@xxxxxxxxxxxxxx
> > Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> > ---
> >  tools/perf/ui/hist.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> > 
> > diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
> > index feb2174ddd1f..a0fee2ac8599 100644
> > --- a/tools/perf/ui/hist.c
> > +++ b/tools/perf/ui/hist.c
> > @@ -614,15 +614,15 @@ void perf_hpp__reset_output_field(struct perf_hpp_list *list)
> >  
> >  	/* reset output fields */
> >  	perf_hpp_list__for_each_format_safe(list, fmt, tmp) {
> > -		list_del_init(&fmt->list);
> > -		list_del_init(&fmt->sort_list);
> > +		list_del(&fmt->list);
> > +		/* Remove the fmt from next loop processing. */
> > +		list_del(&fmt->sort_list);
> 
> Why not just add the comment and leave it as list_del_init(), then, in
> fmt_free() -> fmt->free() -> hse_free() (for instance), have:
> 
> 	BUG_ON(!list_empty(&fmt->list));
> 	BUG_ON(!list_empty(&fmt->sort_list));
> 
> The patch would be smaller and overall the code would be more robust?

ok, that could catch something.. will change

thanks,
jirka