[PATCH v2 2/3] perf stat-shadow: Read tool events directly

[Ian Rogers <irogers@google.com>]

When reading time values for metrics don't use the globals updated in
builtin-stat, just read the events as regular events. The only
exception is for time events where nanoseconds need converting to
seconds as metrics assume time metrics are in seconds.

Signed-off-by: Ian Rogers <irogers@google.com>
---
v2. Make sure that tool time events read from the aggregation index for CPU0.
---
 tools/perf/util/stat-shadow.c | 147 +++++++++++++++-------------------
 1 file changed, 66 insertions(+), 81 deletions(-)

diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index abaf6b579bfc..939ac3269a44 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -371,7 +371,32 @@ static void print_nsecs(struct perf_stat_config *config,
 	}
 }
 
-static int prepare_metric(const struct metric_expr *mexp,
+static bool tool_pmu__is_time_event(const struct perf_stat_config *config,
+				    const struct evsel *evsel, int *tool_aggr_idx)
+{
+	enum tool_pmu_event event = evsel__tool_event(evsel);
+	int aggr_idx;
+
+	if (event != TOOL_PMU__EVENT_DURATION_TIME &&
+	    event != TOOL_PMU__EVENT_USER_TIME &&
+	    event != TOOL_PMU__EVENT_SYSTEM_TIME)
+		return false;
+
+	if (config) {
+		cpu_aggr_map__for_each_idx(aggr_idx, config->aggr_map) {
+			if (config->aggr_map->map[aggr_idx].cpu.cpu == 0) {
+				*tool_aggr_idx = aggr_idx;
+				return true;
+			}
+		}
+		pr_debug("Unexpected CPU0 missing in aggregation for tool event.\n");
+	}
+	*tool_aggr_idx = 0; /* Assume the first aggregation index works. */
+	return true;
+}
+
+static int prepare_metric(const struct perf_stat_config *config,
+			  const struct metric_expr *mexp,
 			  const struct evsel *evsel,
 			  struct expr_parse_ctx *pctx,
 			  int aggr_idx)
@@ -381,91 +406,51 @@ static int prepare_metric(const struct metric_expr *mexp,
 	int i;
 
 	for (i = 0; metric_events[i]; i++) {
+		int source_count = 0, tool_aggr_idx;
+		bool is_tool_time =
+			tool_pmu__is_time_event(config, metric_events[i], &tool_aggr_idx);
+		struct perf_stat_evsel *ps = metric_events[i]->stats;
+		struct perf_stat_aggr *aggr;
 		char *n;
 		double val;
-		int source_count = 0;
 
-		if (evsel__is_tool(metric_events[i])) {
-			struct stats *stats;
-			double scale;
-
-			switch (evsel__tool_event(metric_events[i])) {
-			case TOOL_PMU__EVENT_DURATION_TIME:
-				stats = &walltime_nsecs_stats;
-				scale = 1e-9;
-				break;
-			case TOOL_PMU__EVENT_USER_TIME:
-				stats = &ru_stats.ru_utime_usec_stat;
-				scale = 1e-6;
-				break;
-			case TOOL_PMU__EVENT_SYSTEM_TIME:
-				stats = &ru_stats.ru_stime_usec_stat;
-				scale = 1e-6;
+		/*
+		 * If there are multiple uncore PMUs and we're not reading the
+		 * leader's stats, determine the stats for the appropriate
+		 * uncore PMU.
+		 */
+		if (evsel && evsel->metric_leader &&
+		    evsel->pmu != evsel->metric_leader->pmu &&
+		    mexp->metric_events[i]->pmu == evsel->metric_leader->pmu) {
+			struct evsel *pos;
+
+			evlist__for_each_entry(evsel->evlist, pos) {
+				if (pos->pmu != evsel->pmu)
+					continue;
+				if (pos->metric_leader != mexp->metric_events[i])
+					continue;
+				ps = pos->stats;
+				source_count = 1;
 				break;
-			case TOOL_PMU__EVENT_NONE:
-				pr_err("Invalid tool event 'none'");
-				abort();
-			case TOOL_PMU__EVENT_MAX:
-				pr_err("Invalid tool event 'max'");
-				abort();
-			case TOOL_PMU__EVENT_HAS_PMEM:
-			case TOOL_PMU__EVENT_NUM_CORES:
-			case TOOL_PMU__EVENT_NUM_CPUS:
-			case TOOL_PMU__EVENT_NUM_CPUS_ONLINE:
-			case TOOL_PMU__EVENT_NUM_DIES:
-			case TOOL_PMU__EVENT_NUM_PACKAGES:
-			case TOOL_PMU__EVENT_SLOTS:
-			case TOOL_PMU__EVENT_SMT_ON:
-			case TOOL_PMU__EVENT_SYSTEM_TSC_FREQ:
-			default:
-				pr_err("Unexpected tool event '%s'", evsel__name(metric_events[i]));
-				abort();
 			}
-			val = avg_stats(stats) * scale;
-			source_count = 1;
-		} else {
-			struct perf_stat_evsel *ps = metric_events[i]->stats;
-			struct perf_stat_aggr *aggr;
-
+		}
+		/* Time events are always on CPU0, the first aggregation index. */
+		aggr = &ps->aggr[is_tool_time ? tool_aggr_idx : aggr_idx];
+		if (!aggr || !metric_events[i]->supported) {
 			/*
-			 * If there are multiple uncore PMUs and we're not
-			 * reading the leader's stats, determine the stats for
-			 * the appropriate uncore PMU.
+			 * Not supported events will have a count of 0, which
+			 * can be confusing in a metric. Explicitly set the
+			 * value to NAN. Not counted events (enable time of 0)
+			 * are read as 0.
 			 */
-			if (evsel && evsel->metric_leader &&
-			    evsel->pmu != evsel->metric_leader->pmu &&
-			    mexp->metric_events[i]->pmu == evsel->metric_leader->pmu) {
-				struct evsel *pos;
-
-				evlist__for_each_entry(evsel->evlist, pos) {
-					if (pos->pmu != evsel->pmu)
-						continue;
-					if (pos->metric_leader != mexp->metric_events[i])
-						continue;
-					ps = pos->stats;
-					source_count = 1;
-					break;
-				}
-			}
-			aggr = &ps->aggr[aggr_idx];
-			if (!aggr)
-				break;
-
-			if (!metric_events[i]->supported) {
-				/*
-				 * Not supported events will have a count of 0,
-				 * which can be confusing in a
-				 * metric. Explicitly set the value to NAN. Not
-				 * counted events (enable time of 0) are read as
-				 * 0.
-				 */
-				val = NAN;
-				source_count = 0;
-			} else {
-				val = aggr->counts.val;
-				if (!source_count)
-					source_count = evsel__source_count(metric_events[i]);
-			}
+			val = NAN;
+			source_count = 0;
+		} else {
+			val = aggr->counts.val;
+			if (is_tool_time)
+				val *= 1e-9; /* Convert time event nanoseconds to seconds. */
+			if (!source_count)
+				source_count = evsel__source_count(metric_events[i]);
 		}
 		n = strdup(evsel__metric_id(metric_events[i]));
 		if (!n)
@@ -511,7 +496,7 @@ static void generic_metric(struct perf_stat_config *config,
 		pctx->sctx.user_requested_cpu_list = strdup(config->user_requested_cpu_list);
 	pctx->sctx.runtime = runtime;
 	pctx->sctx.system_wide = config->system_wide;
-	i = prepare_metric(mexp, evsel, pctx, aggr_idx);
+	i = prepare_metric(config, mexp, evsel, pctx, aggr_idx);
 	if (i < 0) {
 		expr__ctx_free(pctx);
 		return;
@@ -572,7 +557,7 @@ double test_generic_metric(struct metric_expr *mexp, int aggr_idx)
 	if (!pctx)
 		return NAN;
 
-	if (prepare_metric(mexp, /*evsel=*/NULL, pctx, aggr_idx) < 0)
+	if (prepare_metric(/*config=*/NULL, mexp, /*evsel=*/NULL, pctx, aggr_idx) < 0)
 		goto out;
 
 	if (expr__parse(&ratio, pctx, mexp->metric_expr))
-- 
2.51.2.1006.ga50a493c49-goog