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perf stat: Fix --no-scale 

The -c option to enable multiplex scaling has been useless for quite
some time because scaling is default.

It's only useful as --no-scale to disable scaling. But the non scaling
code path has bitrotted and doesn't print anything because perf output
code relies on value run/ena information.

Also even when we don't want to scale a value it's still useful to show
its multiplex percentage.

This patch:
  - Fixes help and documentation to show --no-scale instead of -c
  - Removes -c, only keeps the long option because -c doesn't support negatives.
  - Enables running/enabled even with --no-scale
  - And fixes some other problems in the no-scale output.

Before:

  $ perf stat --no-scale -e cycles true

   Performance counter stats for 'true':

       <not counted>      cycles

         0.000984154 seconds time elapsed

After:

  $ ./perf stat --no-scale -e cycles true

   Performance counter stats for 'true':

             706,070      cycles

         0.001219821 seconds time elapsed

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LPU-Reference: 20190314225002.30108-9-andi@firstfloor.org
Link: https://lkml.kernel.org/n/tip-xggjvwcdaj2aqy8ib3i4b1g6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
hifive-unleashed-5.1
Andi Kleen 2019-03-14 15:50:01 -07:00 committed by Arnaldo Carvalho de Melo
parent 90b10f47c0
commit 75998bb263
4 changed files with 9 additions and 14 deletions
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5
tools/perf/Documentation/perf-stat.txt
View File

@ -72,9 +72,8 @@ report::
--all-cpus::
system-wide collection from all CPUs (default if no target is specified)
-c::
--scale::
scale/normalize counter values
--no-scale::
Don't scale/normalize counter values
-d::
--detailed::

3
tools/perf/builtin-stat.c
View File

@ -718,7 +718,8 @@ static struct option stat_options[] = {
"system-wide collection from all CPUs"),
OPT_BOOLEAN('g', "group", &group,
"put the counters into a counter group"),
OPT_BOOLEAN('c', "scale", &stat_config.scale, "scale/normalize counters"),
OPT_BOOLEAN(0, "scale", &stat_config.scale,
"Use --no-scale to disable counter scaling for multiplexing"),
OPT_INCR('v', "verbose", &verbose,
"be more verbose (show counter open errors, etc)"),
OPT_INTEGER('r', "repeat", &stat_config.run_count,

3
tools/perf/util/evsel.c
View File

@ -1344,8 +1344,7 @@ void perf_counts_values__scale(struct perf_counts_values *count,
scaled = 1;
count->val = (u64)((double) count->val * count->ena / count->run + 0.5);
}
} else
count->ena = count->run = 0;
}
if (pscaled)
*pscaled = scaled;

12
tools/perf/util/stat.c
View File

@ -291,10 +291,8 @@ process_counter_values(struct perf_stat_config *config, struct perf_evsel *evsel
break;
case AGGR_GLOBAL:
aggr->val += count->val;
if (config->scale) {
aggr->ena += count->ena;
aggr->run += count->run;
}
aggr->ena += count->ena;
aggr->run += count->run;
case AGGR_UNSET:
default:
break;
@ -442,10 +440,8 @@ int create_perf_stat_counter(struct perf_evsel *evsel,
struct perf_event_attr *attr = &evsel->attr;
struct perf_evsel *leader = evsel->leader;
if (config->scale) {
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING;
}
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING;
/*
* The event is part of non trivial group, let's enable