Re: [PATCH 1/2] perf top: Decay all events in the evlist

From: Arnaldo Carvalho de Melo
Date: Wed Aug 28 2019 - 09:09:25 EST


Em Wed, Aug 28, 2019 at 08:15:54AM +0900, Namhyung Kim escreveu:
> Currently perf top only decays entries in a selected evsel. I don't
> know whether it's intended (maybe due to performance reason?) but
> anyway it might show incorrect output when event group is used since
> users will see leader event is decayed but others are not.
>
> This patch moves the decay code into evlist__resort_hists() so that
> stdio and tui code shared the logic.
>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> tools/perf/builtin-top.c | 38 +++++++++++++-------------------------
> 1 file changed, 13 insertions(+), 25 deletions(-)
>
> diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
> index 5970723cd55a..9d3059d2029d 100644
> --- a/tools/perf/builtin-top.c
> +++ b/tools/perf/builtin-top.c
> @@ -264,13 +264,23 @@ static void perf_top__show_details(struct perf_top *top)
> pthread_mutex_unlock(&notes->lock);
> }
>
> -static void evlist__resort_hists(struct evlist *evlist)
> +static void evlist__resort_hists(struct perf_top *t)

Since this now operates on the perf_top struct, I'll rename it to
perf_top__resort_hists(), ok? No need to send an updated patch.

- Arnaldo

> {
> + struct evlist *evlist = t->evlist;
> struct evsel *pos;
>
> evlist__for_each_entry(evlist, pos) {
> struct hists *hists = evsel__hists(pos);
>
> + if (evlist->enabled) {
> + if (t->zero) {
> + hists__delete_entries(hists);
> + } else {
> + hists__decay_entries(hists, t->hide_user_symbols,
> + t->hide_kernel_symbols);
> + }
> + }
> +
> hists__collapse_resort(hists, NULL);
>
> /* Non-group events are considered as leader */
> @@ -319,16 +329,7 @@ static void perf_top__print_sym_table(struct perf_top *top)
> return;
> }
>
> - if (top->evlist->enabled) {
> - if (top->zero) {
> - hists__delete_entries(hists);
> - } else {
> - hists__decay_entries(hists, top->hide_user_symbols,
> - top->hide_kernel_symbols);
> - }
> - }
> -
> - evlist__resort_hists(top->evlist);
> + evlist__resort_hists(top);
>
> hists__output_recalc_col_len(hists, top->print_entries - printed);
> putchar('\n');
> @@ -576,24 +577,11 @@ static bool perf_top__handle_keypress(struct perf_top *top, int c)
> static void perf_top__sort_new_samples(void *arg)
> {
> struct perf_top *t = arg;
> - struct evsel *evsel = t->sym_evsel;
> - struct hists *hists;
>
> if (t->evlist->selected != NULL)
> t->sym_evsel = t->evlist->selected;
>
> - hists = evsel__hists(evsel);
> -
> - if (t->evlist->enabled) {
> - if (t->zero) {
> - hists__delete_entries(hists);
> - } else {
> - hists__decay_entries(hists, t->hide_user_symbols,
> - t->hide_kernel_symbols);
> - }
> - }
> -
> - evlist__resort_hists(t->evlist);
> + evlist__resort_hists(t);
>
> if (t->lost || t->drop)
> pr_warning("Too slow to read ring buffer (change period (-c/-F) or limit CPUs (-C)\n");
> --
> 2.23.0.187.g17f5b7556c-goog

--

- Arnaldo