[PATCH v5 3/6] perf stat: Avoid printing cpus with no counters

From: Ian Rogers
Date: Tue May 03 2022 - 00:18:29 EST


perf_evlist's user_requested_cpus can contain CPUs not present in any
evsel's cpus, for example uncore counters. Avoid printing the prefix and
trailing \n until the first valid counter is encountered.

Reviewed-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/stat-display.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index d9629a83aa78..13f705737367 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c
@@ -948,8 +948,6 @@ static void print_no_aggr_metric(struct perf_stat_config *config,
struct evsel *counter;
bool first = true;

- if (prefix)
- fputs(prefix, config->output);
evlist__for_each_entry(evlist, counter) {
u64 ena, run, val;
double uval;
@@ -961,6 +959,8 @@ static void print_no_aggr_metric(struct perf_stat_config *config,

id = aggr_cpu_id__cpu(cpu, /*data=*/NULL);
if (first) {
+ if (prefix)
+ fputs(prefix, config->output);
aggr_printout(config, counter, id, 0);
first = false;
}
@@ -972,7 +972,8 @@ static void print_no_aggr_metric(struct perf_stat_config *config,
printout(config, id, 0, counter, uval, prefix,
run, ena, 1.0, &rt_stat);
}
- fputc('\n', config->output);
+ if (!first)
+ fputc('\n', config->output);
}
}

--
2.36.0.464.gb9c8b46e94-goog