perf metrics: Copy entire pmu_event in find metric

The pmu_event passed to the pmu_events_table_for_each_event is invalid
after the loop. Copy the entire struct in metricgroup__find_metric.
Reduce the scope of this function to static.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20220812230949.683239-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 42a5c8a..464475f 100644 (file)
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -879,6 +879,10 @@ struct metricgroup_add_iter_data {
        const struct pmu_events_table *table;
 };
 
+static bool metricgroup__find_metric(const char *metric,
+                                    const struct pmu_events_table *table,
+                                    struct pmu_event *pe);
+
 static int add_metric(struct list_head *metric_list,
                      const struct pmu_event *pe,
                      const char *modifier,
@@ -914,7 +918,7 @@ static int resolve_metric(struct list_head *metric_list,
        size_t bkt;
        struct to_resolve {
                /* The metric to resolve. */
-               const struct pmu_event *pe;
+               struct pmu_event pe;
                /*
                 * The key in the IDs map, this may differ from in case,
                 * etc. from pe->metric_name.
@@ -928,16 +932,15 @@ static int resolve_metric(struct list_head *metric_list,
         * the pending array.
         */
        hashmap__for_each_entry(root_metric->pctx->ids, cur, bkt) {
-               const struct pmu_event *pe;
+               struct pmu_event pe;
 
-               pe = metricgroup__find_metric(cur->key, table);
-               if (pe) {
+               if (metricgroup__find_metric(cur->key, table, &pe)) {
                        pending = realloc(pending,
                                        (pending_cnt + 1) * sizeof(struct to_resolve));
                        if (!pending)
                                return -ENOMEM;
 
-                       pending[pending_cnt].pe = pe;
+                       memcpy(&pending[pending_cnt].pe, &pe, sizeof(pe));
                        pending[pending_cnt].key = cur->key;
                        pending_cnt++;
                }
@@ -952,7 +955,7 @@ static int resolve_metric(struct list_head *metric_list,
         * context.
         */
        for (i = 0; i < pending_cnt; i++) {
-               ret = add_metric(metric_list, pending[i].pe, modifier, metric_no_group,
+               ret = add_metric(metric_list, &pending[i].pe, modifier, metric_no_group,
                                root_metric, visited, table);
                if (ret)
                        break;
@@ -1073,7 +1076,7 @@ static int __add_metric(struct list_head *metric_list,
 
 struct metricgroup__find_metric_data {
        const char *metric;
-       const struct pmu_event *pe;
+       struct pmu_event *pe;
 };
 
 static int metricgroup__find_metric_callback(const struct pmu_event *pe,
@@ -1085,21 +1088,21 @@ static int metricgroup__find_metric_callback(const struct pmu_event *pe,
        if (!match_metric(pe->metric_name, data->metric))
                return 0;
 
-       data->pe = pe;
-       return -1;
+       memcpy(data->pe, pe, sizeof(*pe));
+       return 1;
 }
 
-const struct pmu_event *metricgroup__find_metric(const char *metric,
-                                                const struct pmu_events_table *table)
+static bool metricgroup__find_metric(const char *metric,
+                                    const struct pmu_events_table *table,
+                                    struct pmu_event *pe)
 {
        struct metricgroup__find_metric_data data = {
                .metric = metric,
-               .pe = NULL,
+               .pe = pe,
        };
 
-       pmu_events_table_for_each_event(table, metricgroup__find_metric_callback, &data);
-
-       return data.pe;
+       return pmu_events_table_for_each_event(table, metricgroup__find_metric_callback, &data)
+               ? true : false;
 }
 
 static int add_metric(struct list_head *metric_list,

diff --git a/tools/perf/util/metricgroup.h b/tools/perf/util/metricgroup.h
index f54d170..016b3b1 100644 (file)
--- a/tools/perf/util/metricgroup.h
+++ b/tools/perf/util/metricgroup.h
@@ -69,8 +69,6 @@ int metricgroup__parse_groups(const struct option *opt,
                              bool metric_no_group,
                              bool metric_no_merge,
                              struct rblist *metric_events);
-const struct pmu_event *metricgroup__find_metric(const char *metric,
-                                                const struct pmu_events_table *table);
 int metricgroup__parse_groups_test(struct evlist *evlist,
                                   const struct pmu_events_table *table,
                                   const char *str,