Re: [PATCH 03/22] perf stat: Switch aggregation to use for_each loop

Tidy up the use of cpu and index to hopefully make the code less error
prone. Avoid unused warnings with (void) which will be removed in a
later patch.

In aggr_update_shadow, the perf_cpu_map is switched from
the evlist to the counter's cpu map, so the index is appropriate. This
addresses a problem where uncore counts, with a cpumap like:
$ cat /sys/devices/uncore_imc_0/cpumask
0,18
Don't aggregate counts in CPUs based on the index of those values in the
cpumap (0 and 1) but on the actual CPU (0 and 18). Thereby correcting
metric calculations in per-socket mode for counters with without a full
cpumask.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/stat-display.c | 48 +++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 21 deletions(-)

diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index 588601000f3f..efab39a759ff 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c

@@ -330,8 +330,8 @@ static void print_metric_header(struct perf_stat_config *config,
 static int first_shadow_cpu(struct perf_stat_config *config,
 			    struct evsel *evsel, struct aggr_cpu_id id)
 {
-	struct evlist *evlist = evsel->evlist;
-	int i;
+	struct perf_cpu_map *cpus;
+	int cpu, idx;
 
 	if (config->aggr_mode == AGGR_NONE)
 		return id.core;

@@ -339,14 +339,11 @@ static int first_shadow_cpu(struct perf_stat_config *config,
 	if (!config->aggr_get_id)
 		return 0;
 
-	for (i = 0; i < evsel__nr_cpus(evsel); i++) {
-		int cpu2 = evsel__cpus(evsel)->map[i];
-
-		if (cpu_map__compare_aggr_cpu_id(
-					config->aggr_get_id(config, evlist->core.cpus, cpu2),
-					id)) {
-			return cpu2;
-		}
+	cpus = evsel__cpus(evsel);
+	perf_cpu_map__for_each_cpu(cpu, idx, cpus) {
+		if (cpu_map__compare_aggr_cpu_id(config->aggr_get_id(config, cpus, idx),
+						 id))
+			return cpu;