linux-kernel - Re: [PATCH 1/1] Revert "perf hist: Fix bogus profiles when filters are enabled"

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Message-ID: <CACT4Y+YX-ROx0cW4pkDnqbdfbigVycwPLwO12RNbbtX9-Qp73A@mail.gmail.com>
Date: Wed, 20 Aug 2025 18:14:08 -0700
From: Dmitry Vyukov <dvyukov@...gle.com>
To: Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: Namhyung Kim <namhyung@...nel.org>, Adrian Hunter <adrian.hunter@...el.com>, 
	Ian Rogers <irogers@...gle.com>, James Clark <james.clark@...aro.org>, 
	Jiri Olsa <jolsa@...nel.org>, Kan Liang <kan.liang@...ux.intel.com>, 
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>, linux-perf-users@...r.kernel.org
Subject: Re: [PATCH 1/1] Revert "perf hist: Fix bogus profiles when filters
 are enabled"

On Wed, 20 Aug 2025 at 10:23, Arnaldo Carvalho de Melo <acme@...nel.org> wrote:
>
> This reverts commit 8b4799e4f0f40a4ec737bf870aa38d06288bf0fb.
>
> Not combining entries in 'perf top', so we're getting multiple lines for
> the same symbol, with the same address.
>
> To test it, simply run 'perf top', then do /acpi to see just symbols
> starting with acpi_ and notice that there are various lines with the
> same symbol, press V to see the address and its the same.

With this revert, does it show 1 entry but with a wrong percent?
I am not sure why there are 2 entries for the same symbol, but if we
merge them, we can sum of percents. Is it the right thing to do?

> Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
> ---
>  tools/perf/util/hist.c | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
>
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index 64ff427040c34112..f3f64aff9b882303 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -1391,16 +1391,7 @@ hist_entry__cmp_impl(struct perf_hpp_list *hpp_list, struct hist_entry *left,
>         struct hists *hists = left->hists;
>         struct perf_hpp_fmt *fmt;
>         perf_hpp_fmt_cmp_t *fn;
> -       int64_t cmp;
> -
> -       /*
> -        * Never collapse filtered and non-filtered entries.
> -        * Note this is not the same as having an extra (invisible) fmt
> -        * that corresponds to the filtered status.
> -        */
> -       cmp = (int64_t)!!left->filtered - (int64_t)!!right->filtered;
> -       if (cmp)
> -               return cmp;
> +       int64_t cmp = 0;
>
>         perf_hpp_list__for_each_sort_list(hpp_list, fmt) {
>                 if (ignore_dynamic && perf_hpp__is_dynamic_entry(fmt) &&
> --
> 2.50.1
>