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 <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Michael Petlan <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected] # 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
On Wed, Jan 08, 2020 at 08:30:30PM -0800, 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 <[email protected]>
> Cc: Jiri Olsa <[email protected]>
> Cc: Andi Kleen <[email protected]>
> Cc: Arnaldo Carvalho de Melo <[email protected]>
> Cc: Alexander Shishkin <[email protected]>
> Cc: Michael Petlan <[email protected]>
> Cc: Namhyung Kim <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Cc: [email protected] # 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;
that change looks right, but I can't see how that could
happened because of change in Fixes: tag
was the return statement of this function:
return tot_hitm_left - tot_hitm_right;
considered to be 'unsigned int' and then converted to int64_t,
which would treat negative 'unsigned int' as big positive 'int64_t'?
thanks,
jirka
>
> 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
>
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 <[email protected]>
Tested on top of Arnaldo's perf/core branch. After the patch, the rows
are ordered by Tot Hitm.
Tested-by: Michael Petlan <[email protected]>
> Cc: Jiri Olsa <[email protected]>
> Cc: Andi Kleen <[email protected]>
> Cc: Arnaldo Carvalho de Melo <[email protected]>
> Cc: Alexander Shishkin <[email protected]>
> Cc: Michael Petlan <[email protected]>
> Cc: Namhyung Kim <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Cc: [email protected] # 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
>
>
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 <[email protected]>
>
> Tested on top of Arnaldo's perf/core branch. After the patch, the rows
> are ordered by Tot Hitm.
>
> Tested-by: Michael Petlan <[email protected]>
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 <[email protected]>
> > Cc: Andi Kleen <[email protected]>
> > Cc: Arnaldo Carvalho de Melo <[email protected]>
> > Cc: Alexander Shishkin <[email protected]>
> > Cc: Michael Petlan <[email protected]>
> > Cc: Namhyung Kim <[email protected]>
> > Cc: Peter Zijlstra <[email protected]>
> > Cc: [email protected] # 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
> >
> >
On Thu, Jan 09, 2020 at 10:18:34AM -0300, Arnaldo Carvalho de Melo wrote:
> 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 <[email protected]>
> >
> > Tested on top of Arnaldo's perf/core branch. After the patch, the rows
> > are ordered by Tot Hitm.
> >
> > Tested-by: Michael Petlan <[email protected]>
>
> 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.
waiting for Andres's answer.. making sure I understand the issue ;-)
jirka
>
> - Arnaldo
>
> > > Cc: Jiri Olsa <[email protected]>
> > > Cc: Andi Kleen <[email protected]>
> > > Cc: Arnaldo Carvalho de Melo <[email protected]>
> > > Cc: Alexander Shishkin <[email protected]>
> > > Cc: Michael Petlan <[email protected]>
> > > Cc: Namhyung Kim <[email protected]>
> > > Cc: Peter Zijlstra <[email protected]>
> > > Cc: [email protected] # 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
> > >
> > >
Hi,
On 2020-01-09 09:48:22 +0100, Jiri Olsa wrote:
> On Wed, Jan 08, 2020 at 08:30:30PM -0800, 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 <[email protected]>
> > Cc: Jiri Olsa <[email protected]>
> > Cc: Andi Kleen <[email protected]>
> > Cc: Arnaldo Carvalho de Melo <[email protected]>
> > Cc: Alexander Shishkin <[email protected]>
> > Cc: Michael Petlan <[email protected]>
> > Cc: Namhyung Kim <[email protected]>
> > Cc: Peter Zijlstra <[email protected]>
> > Cc: [email protected] # 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;
>
> that change looks right, but I can't see how that could
> happened because of change in Fixes: tag
>
> was the return statement of this function:
>
> return tot_hitm_left - tot_hitm_right;
>
> considered to be 'unsigned int' and then converted to int64_t,
> which would treat negative 'unsigned int' as big positive 'int64_t'?
Correct. So e.g. when comparing 1 and 2 tot_hitm, we'd get (int64_t)
UINT_MAX as a result, which is obviously wrong. However, due to
hist_entry__sort() returning int at the time, this was masked, as the
int64_t was cast to int. Thereby again yielding a negative number for
the comparisons of hist_entry__sort()'s result. After
hist_entry__sort() was fixed however, there never could be negative
return values (but 0's are possible) of hist_entry__sort() for c2c.
I briefly looked for places outside of c2c for similar issues in
hist_entry comparison routines, but didn't find any.
Greetings,
Andres Freund
On Thu, Jan 09, 2020 at 09:00:41AM -0800, Andres Freund wrote:
SNIP
> > > 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;
> >
> > that change looks right, but I can't see how that could
> > happened because of change in Fixes: tag
> >
> > was the return statement of this function:
> >
> > return tot_hitm_left - tot_hitm_right;
> >
> > considered to be 'unsigned int' and then converted to int64_t,
> > which would treat negative 'unsigned int' as big positive 'int64_t'?
>
> Correct. So e.g. when comparing 1 and 2 tot_hitm, we'd get (int64_t)
> UINT_MAX as a result, which is obviously wrong. However, due to
> hist_entry__sort() returning int at the time, this was masked, as the
> int64_t was cast to int. Thereby again yielding a negative number for
> the comparisons of hist_entry__sort()'s result. After
> hist_entry__sort() was fixed however, there never could be negative
> return values (but 0's are possible) of hist_entry__sort() for c2c.
I see.. ok
Acked-by: Jiri Olsa <[email protected]>
thanks,
jirka
Em Thu, Jan 09, 2020 at 10:46:11PM +0100, Jiri Olsa escreveu:
> On Thu, Jan 09, 2020 at 09:00:41AM -0800, Andres Freund wrote:
>
> SNIP
>
> > > > 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;
> > >
> > > that change looks right, but I can't see how that could
> > > happened because of change in Fixes: tag
> > >
> > > was the return statement of this function:
> > >
> > > return tot_hitm_left - tot_hitm_right;
> > >
> > > considered to be 'unsigned int' and then converted to int64_t,
> > > which would treat negative 'unsigned int' as big positive 'int64_t'?
> >
> > Correct. So e.g. when comparing 1 and 2 tot_hitm, we'd get (int64_t)
> > UINT_MAX as a result, which is obviously wrong. However, due to
> > hist_entry__sort() returning int at the time, this was masked, as the
> > int64_t was cast to int. Thereby again yielding a negative number for
> > the comparisons of hist_entry__sort()'s result. After
> > hist_entry__sort() was fixed however, there never could be negative
> > return values (but 0's are possible) of hist_entry__sort() for c2c.
>
> I see.. ok
>
> Acked-by: Jiri Olsa <[email protected]>
Thanks, applied.
- Arnaldo
The following commit has been merged into the perf/core branch of tip:
Commit-ID: c1c8013ec34d7163431d18367808ea40b2e305f8
Gitweb: https://git.kernel.org/tip/c1c8013ec34d7163431d18367808ea40b2e305f8
Author: Andres Freund <[email protected]>
AuthorDate: Wed, 08 Jan 2020 20:30:30 -08:00
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitterDate: Tue, 14 Jan 2020 13:29:21 -03:00
perf c2c: Fix return type for histogram sorting comparision functions
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 <[email protected]>
Tested-by: Michael Petlan <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected] # v3.16+
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
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 3463512..246ac0b 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)