Re: [PATCH] perf c2c: Fix sorting.
From: Arnaldo Carvalho de Melo
Date: Thu Jan 09 2020 - 08:18:48 EST
Em Thu, Jan 09, 2020 at 10:58:43AM +0100, Michael Petlan escreveu:
> On Wed, 8 Jan 2020, Andres Freund wrote:
> > Commit 722ddfde366f ("perf tools: Fix time sorting") changed -
> > correctly so - hist_entry__sort to return int64. Unfortunately several
> > of the builtin-c2c.c comparison routines only happened to work due the
> > cast caused by the wrong return type.
> >
> > This causes meaningless ordering of both the cacheline list, and the
> > cacheline details page. E.g a simple
> > perf c2c record -a sleep 3
> > perf c2c report
> > will result in cacheline table like
> > =================================================
> > Shared Data Cache Line Table
> > =================================================
> > #
> > # ----------- Cacheline ---------- Total Tot ----- LLC Load Hitm ----- ---- Store Reference ---- --- Load Dram ---- LLC Total ----- Core Load Hit ----- -- LLC Load Hit --
> > # Index Address Node PA cnt records Hitm Total Lcl Rmt Total L1Hit L1Miss Lcl Rmt Ld Miss Loads FB L1 L2 Llc Rmt
> > # ..... .................. .... ...... ....... ....... ....... ....... ....... ....... ....... ....... ........ ........ ....... ....... ....... ....... ....... ........ ........
> > #
> > 0 0x7f0d27ffba00 N/A 0 52 0.12% 13 6 7 12 12 0 0 7 14 40 4 16 0 0 0
> > 1 0x7f0d27ff61c0 N/A 0 6353 14.04% 1475 801 674 779 779 0 0 718 1392 5574 1299 1967 0 115 0
> > 2 0x7f0d26d3ec80 N/A 0 71 0.15% 16 4 12 13 13 0 0 12 24 58 1 20 0 9 0
> > 3 0x7f0d26d3ec00 N/A 0 98 0.22% 23 17 6 19 19 0 0 6 12 79 0 40 0 10 0
> > i.e. with the list not being ordered by Total Hitm.
> >
> > Fixes: 722ddfde366f ("perf tools: Fix time sorting")
> > Signed-off-by: Andres Freund <andres@xxxxxxxxxxx>
>
> Tested on top of Arnaldo's perf/core branch. After the patch, the rows
> are ordered by Tot Hitm.
>
> Tested-by: Michael Petlan <mpetlan@xxxxxxxxxx>
Jiri, so you think we should use a different Fixes: cset? Or plain
remove it? I haven't checked it, just trying to figure out if you guys
came up with a conclusion so that I can review/apply.
- Arnaldo
> > Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> > Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> > Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> > Cc: Michael Petlan <mpetlan@xxxxxxxxxx>
> > Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx # v3.16+
> > ---
> > tools/perf/builtin-c2c.c | 10 ++++++----
> > 1 file changed, 6 insertions(+), 4 deletions(-)
> >
> > diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
> > index e69f44941aad..f2e9d2b1b913 100644
> > --- a/tools/perf/builtin-c2c.c
> > +++ b/tools/perf/builtin-c2c.c
> > @@ -595,8 +595,8 @@ tot_hitm_cmp(struct perf_hpp_fmt *fmt __maybe_unused,
> > {
> > struct c2c_hist_entry *c2c_left;
> > struct c2c_hist_entry *c2c_right;
> > - unsigned int tot_hitm_left;
> > - unsigned int tot_hitm_right;
> > + uint64_t tot_hitm_left;
> > + uint64_t tot_hitm_right;
> >
> > c2c_left = container_of(left, struct c2c_hist_entry, he);
> > c2c_right = container_of(right, struct c2c_hist_entry, he);
> > @@ -629,7 +629,8 @@ __f ## _cmp(struct perf_hpp_fmt *fmt __maybe_unused, \
> > \
> > c2c_left = container_of(left, struct c2c_hist_entry, he); \
> > c2c_right = container_of(right, struct c2c_hist_entry, he); \
> > - return c2c_left->stats.__f - c2c_right->stats.__f; \
> > + return (uint64_t) c2c_left->stats.__f - \
> > + (uint64_t) c2c_right->stats.__f; \
> > }
> >
> > #define STAT_FN(__f) \
> > @@ -682,7 +683,8 @@ ld_llcmiss_cmp(struct perf_hpp_fmt *fmt __maybe_unused,
> > c2c_left = container_of(left, struct c2c_hist_entry, he);
> > c2c_right = container_of(right, struct c2c_hist_entry, he);
> >
> > - return llc_miss(&c2c_left->stats) - llc_miss(&c2c_right->stats);
> > + return (uint64_t) llc_miss(&c2c_left->stats) -
> > + (uint64_t) llc_miss(&c2c_right->stats);
> > }
> >
> > static uint64_t total_records(struct c2c_stats *stats)
> > --
> > 2.25.0.rc1
> >
> >