Re: [PATCH 3/7] perf, tools, stat: Support metrics in --per-core/socket mode

From: Andi Kleen
Date: Tue Mar 01 2016 - 13:52:55 EST


On Tue, Mar 01, 2016 at 01:31:49PM +0100, Jiri Olsa wrote:
> On Mon, Feb 29, 2016 at 02:36:22PM -0800, Andi Kleen wrote:
> > From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> >
> > Enable metrics printing in --per-core / --per-socket mode. We need
> > to save the shadow metrics in a unique place. Always use the first
> > CPU in the aggregation. Then use the same CPU to retrieve the
> > shadow value later.
> >
> > Example output:
> >
> > % perf stat --per-core -a ./BC1s
> >
> > Performance counter stats for 'system wide':
> >
> > S0-C0 2 2966.020381 task-clock (msec) # 2.004 CPUs utilized (100.00%)
> > S0-C0 2 49 context-switches # 0.017 K/sec (100.00%)
> > S0-C0 2 4 cpu-migrations # 0.001 K/sec (100.00%)
> > S0-C0 2 467 page-faults # 0.157 K/sec
> > S0-C0 2 4,599,061,773 cycles # 1.551 GHz (100.00%)
> > S0-C0 2 9,755,886,883 instructions # 2.12 insn per cycle (100.00%)
> > S0-C0 2 1,906,272,125 branches # 642.704 M/sec (100.00%)
> > S0-C0 2 81,180,867 branch-misses # 4.26% of all branches
> > S0-C1 2 2965.995373 task-clock (msec) # 2.003 CPUs utilized (100.00%)
> > S0-C1 2 62 context-switches # 0.021 K/sec (100.00%)
> > S0-C1 2 8 cpu-migrations # 0.003 K/sec (100.00%)
> > S0-C1 2 281 page-faults # 0.095 K/sec
> > S0-C1 2 6,347,290 cycles # 0.002 GHz (100.00%)
> > S0-C1 2 4,654,156 instructions # 0.73 insn per cycle (100.00%)
> > S0-C1 2 947,121 branches # 0.319 M/sec (100.00%)
> > S0-C1 2 37,322 branch-misses # 3.94% of all branches
> >
> > 1.480409747 seconds time elapsed
> >
> > v2: Rebase to older patches
> > v3: Document shadow cpus. Fix aggr_get_id argument. Fix -A shadows (Jiri)
> > Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > ---
> > tools/perf/builtin-stat.c | 61 +++++++++++++++++++++++++++++++++++++------
> > tools/perf/util/stat-shadow.c | 7 +++++
> > 2 files changed, 60 insertions(+), 8 deletions(-)
> >
> > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
> > index 2ffb822..c79e571 100644
> > --- a/tools/perf/builtin-stat.c
> > +++ b/tools/perf/builtin-stat.c
> > @@ -740,6 +740,8 @@ struct outstate {
> > bool newline;
> > const char *prefix;
> > int nfields;
> > + int id, nr;
> > + struct perf_evsel *evsel;
> > };
> >
> > #define METRIC_LEN 35
> > @@ -755,12 +757,9 @@ static void do_new_line_std(struct outstate *os)
> > {
> > fputc('\n', os->fh);
> > fputs(os->prefix, os->fh);
> > + aggr_printout(os->evsel, os->id, os->nr);
> > if (stat_config.aggr_mode == AGGR_NONE)
> > fprintf(os->fh, " ");
>
> any reason for this extra space for AGGR_NONE?

It's just to avoid special cases for NONE elsewhere, as it has
the same alignment. This was there before.

-Andi