[PATCH V3 1/1] perf hists: clear dummy entry accumulated period

[PATCH V3 1/1] perf hists: clear dummy entry accumulated period

[kan.liang]

From: Kan Liang <kan.liang@intel.com>

The accumulated period for dummy entry should also be 0.
Otherwise, the total overhead could be overcounted.
[perf]$ perf record -e '{LLC-load-misses,cpu/instructions/}'
--call-graph=lbr ./tchain
[perf]$ perf report --stdio
 # To display the perf.data header info, please use
 --header/--header-only options.
 #
 #
 # Total Lost Samples: 0
 #
 # Samples: 21K of event 'anon group { LLC-load-misses,
cpu/instructions/
 }'
 # Event count (approx.): 16313667937
 #
 #         Children              Self  Command      Shared Object
 Symbol
 # ................  ................  ...........  ................
 ............................
 #
   4769.98%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
 [k] update_fast_timekeeper
   4356.18%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
 [k] trigger_load_balance
   3181.12%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
 [k] irq_work_tick
   1592.37%   0.00%     0.00%   0.00%  tchain_edit  [kernel.vmlinux]
 [k] cpu_needs_another_gp

Signed-off-by: Kan Liang <kan.liang@intel.com>
---

Changes since V2:
 - Use symbol_conf.cumulate_callchain check for existance of he->stat_acc 
Changes since V1:
 - check he->stat_acc. Because it only be available when option children is set

 tools/perf/util/hist.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 991a351..0f33d7e 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -2062,6 +2062,8 @@ static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
 	if (he) {
 		memset(&he->stat, 0, sizeof(he->stat));
 		he->hists = hists;
+		if (symbol_conf.cumulate_callchain)
+			memset(he->stat_acc, 0, sizeof(he->stat));
 		rb_link_node(&he->rb_node_in, parent, p);
 		rb_insert_color(&he->rb_node_in, root);
 		hists__inc_stats(hists, he);
-- 
2.5.0

Re: [PATCH V3 1/1] perf hists: clear dummy entry accumulated period

[Jiri Olsa]

On Sun, Apr 24, 2016 at 11:28:09PM -0700, kan.liang@intel.com wrote:
> From: Kan Liang <kan.liang@intel.com>
> 
> The accumulated period for dummy entry should also be 0.
> Otherwise, the total overhead could be overcounted.
> [perf]$ perf record -e '{LLC-load-misses,cpu/instructions/}'
> --call-graph=lbr ./tchain
> [perf]$ perf report --stdio
>  # To display the perf.data header info, please use
>  --header/--header-only options.
>  #
>  #
>  # Total Lost Samples: 0
>  #
>  # Samples: 21K of event 'anon group { LLC-load-misses,
> cpu/instructions/
>  }'
>  # Event count (approx.): 16313667937
>  #
>  #         Children              Self  Command      Shared Object
>  Symbol
>  # ................  ................  ...........  ................
>  ............................
>  #
>    4769.98%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
>  [k] update_fast_timekeeper
>    4356.18%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
>  [k] trigger_load_balance
>    3181.12%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
>  [k] irq_work_tick
>    1592.37%   0.00%     0.00%   0.00%  tchain_edit  [kernel.vmlinux]
>  [k] cpu_needs_another_gp
> 
> Signed-off-by: Kan Liang <kan.liang@intel.com>
> ---
> 
> Changes since V2:
>  - Use symbol_conf.cumulate_callchain check for existance of he->stat_acc 
> Changes since V1:
>  - check he->stat_acc. Because it only be available when option children is set

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

> 
>  tools/perf/util/hist.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index 991a351..0f33d7e 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -2062,6 +2062,8 @@ static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
>  	if (he) {
>  		memset(&he->stat, 0, sizeof(he->stat));
>  		he->hists = hists;
> +		if (symbol_conf.cumulate_callchain)
> +			memset(he->stat_acc, 0, sizeof(he->stat));
>  		rb_link_node(&he->rb_node_in, parent, p);
>  		rb_insert_color(&he->rb_node_in, root);
>  		hists__inc_stats(hists, he);
> -- 
> 2.5.0
> 

Re: [PATCH V3 1/1] perf hists: clear dummy entry accumulated period

[Arnaldo Carvalho de Melo]

Em Mon, Apr 25, 2016 at 08:15:00PM +0200, Jiri Olsa escreveu:
> On Sun, Apr 24, 2016 at 11:28:09PM -0700, kan.liang@intel.com wrote:
> > From: Kan Liang <kan.liang@intel.com>
> > 
> > The accumulated period for dummy entry should also be 0.
> > Otherwise, the total overhead could be overcounted.
> > [perf]$ perf record -e '{LLC-load-misses,cpu/instructions/}'
> > --call-graph=lbr ./tchain
> > [perf]$ perf report --stdio
> >  # To display the perf.data header info, please use
> >  --header/--header-only options.
> >  #
> >  #
> >  # Total Lost Samples: 0
> >  #
> >  # Samples: 21K of event 'anon group { LLC-load-misses,
> > cpu/instructions/
> >  }'
> >  # Event count (approx.): 16313667937
> >  #
> >  #         Children              Self  Command      Shared Object
> >  Symbol
> >  # ................  ................  ...........  ................
> >  ............................
> >  #
> >    4769.98%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
> >  [k] update_fast_timekeeper
> >    4356.18%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
> >  [k] trigger_load_balance
> >    3181.12%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]
> >  [k] irq_work_tick
> >    1592.37%   0.00%     0.00%   0.00%  tchain_edit  [kernel.vmlinux]
> >  [k] cpu_needs_another_gp
> > 
> > Signed-off-by: Kan Liang <kan.liang@intel.com>
> > ---
> > 
> > Changes since V2:
> >  - Use symbol_conf.cumulate_callchain check for existance of he->stat_acc 
> > Changes since V1:
> >  - check he->stat_acc. Because it only be available when option children is set
> 
> Acked-by: Jiri Olsa <jolsa@kernel.org>

Thanks, applied.

- Arnaldo

[tip:perf/core] perf hists: Clear dummy entry accumulated period

[tip-bot for Kan Liang]

Commit-ID:  09623d79466e996f5dc2753e16f04fda6f078041
Gitweb:     http://git.kernel.org/tip/09623d79466e996f5dc2753e16f04fda6f078041
Author:     Kan Liang <kan.liang@intel.com>
AuthorDate: Sun, 24 Apr 2016 23:28:09 -0700
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Mon, 25 Apr 2016 20:35:59 -0300

perf hists: Clear dummy entry accumulated period

The accumulated period for dummy entry should also be 0.  Otherwise, the
total overhead could be overcounted.

  $ perf record -e '{LLC-load-misses,cpu/instructions/}' --call-graph=lbr ./tchain
  $ perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  # Total Lost Samples: 0
  #
  # Samples: 21K of event 'anon group { LLC-load-misses, cpu/instructions/ }'
  # Event count (approx.): 16313667937
  #
  #         Children              Self  Command      Shared Object     Symbol
  # ................  ................  ...........  ................  ............................
  #
    4769.98%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]  [k] update_fast_timekeeper
    4356.18%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]  [k] trigger_load_balance
    3181.12%   0.01%     0.00%   0.01%  tchain_edit  [kernel.vmlinux]  [k] irq_work_tick
    1592.37%   0.00%     0.00%   0.00%  tchain_edit  [kernel.vmlinux]  [k] cpu_needs_another_gp

Signed-off-by: Kan Liang <kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1461565689-5862-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/hist.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 991a351..0f33d7e 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -2062,6 +2062,8 @@ static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
 	if (he) {
 		memset(&he->stat, 0, sizeof(he->stat));
 		he->hists = hists;
+		if (symbol_conf.cumulate_callchain)
+			memset(he->stat_acc, 0, sizeof(he->stat));
 		rb_link_node(&he->rb_node_in, parent, p);
 		rb_insert_color(&he->rb_node_in, root);
 		hists__inc_stats(hists, he);