Re: [PATCH 1/5] Revert "perf stat: Support metrics with hybrid events"

From: Xing Zhengjun
Date: Tue May 10 2022 - 05:31:53 EST




On 5/10/2022 5:55 AM, Liang, Kan wrote:


On 5/9/2022 9:12 AM, Arnaldo Carvalho de Melo wrote:
Em Fri, May 06, 2022 at 10:34:06PM -0700, Ian Rogers escreveu:
This reverts commit 60344f1a9a597f2e0efcd57df5dad0b42da15e21.

I picked this from the cover letter and added to this revert, to justify
it:

"Hybrid metrics place a PMU at the end of the parse string. This is
also where tool events are placed. The behavior of the parse string
isn't clear and so revert the change for now."


I think the original patch used a "#" to indicate the PMU name, which can be used to distinguish between the tool events and the PMU name.
To be honest, I'm not sure what's unclear here. Could you please clarify?

With this revert, the issue mentioned in the original patch must be broken on ADL. I don't see a replacement fix in this patch series.
Could you please propose a solution for the issue to replace the #PMU name solution?

Thanks,
Kan

I am surprised the origin patch is reverted during discussion and though the discussion still has no conclusion.
Let me introduce the purpose of the origin patch.
For a hybrid system such as ADL, if both the metrics and the formula are different for the different PMUs, without this patch, the metric and event parser should work ok, nothing should be special for the hybrid. In fact, both "cpu_core" and "cpu_atom" may have the same metrics--the same metric name, even the same formula for the metrics. For example, both "cpu_core" and "cpu_atom" have metrics "IpBranch" and "IPC", For "IpBranch", both "cpu_core" and "cpu_atom" has the same metric name and their formula also is the same, the event name is the same though they belong to different PMUs. The old metric and event parser can not handle this kind of metric, that's why we need this patch.

"MetricExpr": "INST_RETIRED.ANY / BR_INST_RETIRED.ALL_BRANCHES",
"MetricName": "IpBranch",
"Unit": "cpu_core"

"MetricExpr": "INST_RETIRED.ANY / BR_INST_RETIRED.ALL_BRANCHES",
"MetricName": "IpBranch",
"Unit": "cpu_atom"


"MetricExpr": "INST_RETIRED.ANY / CPU_CLK_UNHALTED.THREAD",
"MetricName": "IPC",
"Unit": "cpu_core"

"MetricExpr": "INST_RETIRED.ANY / CPU_CLK_UNHALTED.CORE",
"MetricName": "IPC",
"Unit": "cpu_atom"

Except for the above two metrics, there are still a lot of similar metrics, "CPU_Utilization"...

The original patch expanded the metric group string by adding "#PMU_name" to indicate the PMU name, which can be used to distinguish between the tool events and the PMU name, then the metric and event parser can parse the right PMU for the events.

With the patch all the ADL metrics can pass, without the patch, a lot of metrics will fail. I don't think it's a good idea to revert it before the new solution is proposed.


I apologise for not having provided ample time for reviewing this patch,
sorry about that.

- Arnaldo
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
  tools/perf/util/metricgroup.c  | 263 +++------------------------------
  tools/perf/util/stat-display.c |   8 +-
  2 files changed, 22 insertions(+), 249 deletions(-)

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 126a43a8917e..d8492e339521 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -141,11 +141,6 @@ struct metric {
       * output.
       */
      const char *metric_unit;
-    /**
-     * The name of the CPU such as "cpu_core" or "cpu_atom" in hybrid systems
-     * and "NULL" in non-hybrid systems.
-     */
-    const char *pmu_name;
      /** Optional null terminated array of referenced metrics. */
      struct metric_ref *metric_refs;
      /**
@@ -220,7 +215,6 @@ static struct metric *metric__new(const struct pmu_event *pe,
      }
      m->metric_expr = pe->metric_expr;
      m->metric_unit = pe->unit;
-    m->pmu_name = pe->pmu;
      m->pctx->runtime = runtime;
      m->has_constraint = metric_no_group || metricgroup__has_constraint(pe);
      m->metric_refs = NULL;
@@ -256,12 +250,10 @@ static bool contains_metric_id(struct evsel **metric_events, int num_events,
   * @ids: the metric IDs to match.
   * @metric_evlist: the list of perf events.
   * @out_metric_events: holds the created metric events array.
- * @pmu_name: the name of the CPU.
   */
  static int setup_metric_events(struct hashmap *ids,
                     struct evlist *metric_evlist,
-                   struct evsel ***out_metric_events,
-                   const char *pmu_name)
+                   struct evsel ***out_metric_events)
  {
      struct evsel **metric_events;
      const char *metric_id;
@@ -294,10 +286,6 @@ static int setup_metric_events(struct hashmap *ids,
           * about this event.
           */
          if (hashmap__find(ids, metric_id, (void **)&val_ptr)) {
-            if (evsel__is_hybrid(ev) && pmu_name &&
-                strcmp(pmu_name, ev->pmu_name)) {
-                continue;
-            }
              metric_events[matched_events++] = ev;
              if (matched_events >= ids_size)
@@ -736,8 +724,7 @@ static int decode_all_metric_ids(struct evlist *perf_evlist, const char *modifie
  static int metricgroup__build_event_string(struct strbuf *events,
                         const struct expr_parse_ctx *ctx,
                         const char *modifier,
-                       bool has_constraint,
-                       const char *pmu_name)
+                       bool has_constraint)
  {
      struct hashmap_entry *cur;
      size_t bkt;
@@ -819,18 +806,12 @@ static int metricgroup__build_event_string(struct strbuf *events,
          if (no_group) {
              /* Strange case of a metric of just duration_time. */
              ret = strbuf_addf(events, "duration_time");
-        } else if (!has_constraint) {
-            ret = strbuf_addf(events, "}:W");
-            if (pmu_name)
-                ret = strbuf_addf(events, "#%s", pmu_name);
-            ret = strbuf_addf(events, ",duration_time");
-        } else
+        } else if (!has_constraint)
+            ret = strbuf_addf(events, "}:W,duration_time");
+        else
              ret = strbuf_addf(events, ",duration_time");
-    } else if (!no_group && !has_constraint) {
+    } else if (!no_group && !has_constraint)
          ret = strbuf_addf(events, "}:W");
-        if (pmu_name)
-            ret = strbuf_addf(events, "#%s", pmu_name);
-    }
      return ret;
  #undef RETURN_IF_NON_ZERO
@@ -1169,13 +1150,11 @@ static int metric_list_cmp(void *priv __maybe_unused, const struct list_head *l,
   * @metric_list: The list that the metric or metric group are added to.
   * @map: The map that is searched for metrics, most commonly the table for the
   *       architecture perf is running upon.
- * @pmu_name: the name of the CPU.
   */
-static int metricgroup__add_metric(const char *metric_name,
-                   const char *modifier, bool metric_no_group,
+static int metricgroup__add_metric(const char *metric_name, const char *modifier,
+                   bool metric_no_group,
                     struct list_head *metric_list,
-                   const struct pmu_events_map *map,
-                   const char *pmu_name)
+                   const struct pmu_events_map *map)
  {
      const struct pmu_event *pe;
      LIST_HEAD(list);
@@ -1188,8 +1167,6 @@ static int metricgroup__add_metric(const char *metric_name,
       */
      map_for_each_metric(pe, i, map, metric_name) {
          has_match = true;
-        if (pmu_name && pe->pmu && strcmp(pmu_name, pe->pmu))
-            continue;
          ret = add_metric(&list, pe, modifier, metric_no_group,
                   /*root_metric=*/NULL,
                   /*visited_metrics=*/NULL, map);
@@ -1238,12 +1215,10 @@ static int metricgroup__add_metric(const char *metric_name,
   * @metric_list: The list that metrics are added to.
   * @map: The map that is searched for metrics, most commonly the table for the
   *       architecture perf is running upon.
- * @pmu_name: the name of the CPU.
   */
  static int metricgroup__add_metric_list(const char *list, bool metric_no_group,
                      struct list_head *metric_list,
-                    const struct pmu_events_map *map,
-                    const char *pmu_name)
+                    const struct pmu_events_map *map)
  {
      char *list_itr, *list_copy, *metric_name, *modifier;
      int ret, count = 0;
@@ -1260,7 +1235,7 @@ static int metricgroup__add_metric_list(const char *list, bool metric_no_group,
          ret = metricgroup__add_metric(metric_name, modifier,
                            metric_no_group, metric_list,
-                          map, pmu_name);
+                          map);
          if (ret == -EINVAL)
              pr_err("Cannot find metric or group `%s'\n", metric_name);
@@ -1335,183 +1310,6 @@ static int build_combined_expr_ctx(const struct list_head *metric_list,
      return ret;
  }
-static char *get_metric_pmus(char *orig_str, struct strbuf *metric_pmus)
-{
-    char *llist, *nlist, *p1, *p2, *new_str = NULL;
-    int ret;
-    struct strbuf new_events;
-
-    if (!strchr(orig_str, '#')) {
-        /*
-         * pmu name is added after '#'. If no '#' found,
-         * don't need to process pmu.
-         */
-        return strdup(orig_str);
-    }
-
-    nlist = strdup(orig_str);
-    if (!nlist)
-        return new_str;
-
-    ret = strbuf_init(&new_events, 100);
-    if (ret)
-        goto err_out;
-
-    ret = strbuf_grow(metric_pmus, 100);
-    if (ret)
-        goto err_out;
-
-    llist = nlist;
-    while ((p1 = strsep(&llist, ",")) != NULL) {
-        p2 = strchr(p1, '#');
-        if (p2) {
-            *p2 = 0;
-            ret = strbuf_addf(&new_events, "%s,", p1);
-            if (ret)
-                goto err_out;
-
-            ret = strbuf_addf(metric_pmus, "%s,", p2 + 1);
-            if (ret)
-                goto err_out;
-
-        } else {
-            ret = strbuf_addf(&new_events, "%s,", p1);
-            if (ret)
-                goto err_out;
-        }
-    }
-
-    new_str = strdup(new_events.buf);
-    if (new_str) {
-        /* Remove last ',' */
-        new_str[strlen(new_str) - 1] = 0;
-    }
-err_out:
-    free(nlist);
-    strbuf_release(&new_events);
-    return new_str;
-}
-
-static void set_pmu_unmatched_events(struct evlist *evlist, int group_idx,
-                     char *pmu_name,
-                     unsigned long *evlist_removed)
-{
-    struct evsel *evsel, *pos;
-    int i = 0, j = 0;
-
-    /*
-     * Move to the first evsel of a given group
-     */
-    evlist__for_each_entry(evlist, evsel) {
-        if (evsel__is_group_leader(evsel) &&
-            evsel->core.nr_members >= 1) {
-            if (i < group_idx) {
-                j += evsel->core.nr_members;
-                i++;
-                continue;
-            }
-        }
-    }
-
-    i = 0;
-    evlist__for_each_entry(evlist, evsel) {
-        if (i < j) {
-            i++;
-            continue;
-        }
-
-        /*
-         * Now we are at the first evsel in the group
-         */
-        for_each_group_evsel(pos, evsel) {
-            if (evsel__is_hybrid(pos) &&
-                strcmp(pos->pmu_name, pmu_name)) {
-                set_bit(pos->core.idx, evlist_removed);
-            }
-        }
-        break;
-    }
-}
-
-static void remove_pmu_umatched_events(struct evlist *evlist, char *metric_pmus)
-{
-    struct evsel *evsel, *tmp, *new_leader = NULL;
-    unsigned long *evlist_removed;
-    char *llist, *nlist, *p1;
-    bool need_new_leader = false;
-    int i = 0, new_nr_members = 0;
-
-    nlist = strdup(metric_pmus);
-    if (!nlist)
-        return;
-
-    evlist_removed = bitmap_zalloc(evlist->core.nr_entries);
-    if (!evlist_removed) {
-        free(nlist);
-        return;
-    }
-
-    llist = nlist;
-    while ((p1 = strsep(&llist, ",")) != NULL) {
-        if (strlen(p1) > 0) {
-            /*
-             * p1 points to the string of pmu name, e.g. "cpu_atom".
-             * The metric group string has pmu suffixes, e.g.
-             * "{inst_retired.any,cpu_clk_unhalted.thread}:W#cpu_core,
-             *  {cpu_clk_unhalted.core,inst_retired.any_p}:W#cpu_atom"
-             * By counting the pmu name, we can know the index of
-             * group.
-             */
-            set_pmu_unmatched_events(evlist, i++, p1,
-                         evlist_removed);
-        }
-    }
-
-    evlist__for_each_entry_safe(evlist, tmp, evsel) {
-        if (test_bit(evsel->core.idx, evlist_removed)) {
-            if (!evsel__is_group_leader(evsel)) {
-                if (!need_new_leader) {
-                    if (new_leader)
-                        new_leader->core.leader->nr_members--;
-                    else
-                        evsel->core.leader->nr_members--;
-                } else
-                    new_nr_members--;
-            } else {
-                /*
-                 * If group leader is to remove, we need to
-                 * prepare a new leader and adjust all group
-                 * members.
-                 */
-                need_new_leader = true;
-                new_nr_members =
-                    evsel->core.leader->nr_members - 1;
-            }
-
-            evlist__remove(evlist, evsel);
-            evsel__delete(evsel);
-        } else {
-            if (!evsel__is_group_leader(evsel)) {
-                if (need_new_leader) {
-                    need_new_leader = false;
-                    new_leader = evsel;
-                    new_leader->core.leader =
-                        &new_leader->core;
-                    new_leader->core.nr_members =
-                        new_nr_members;
-                } else if (new_leader)
-                    evsel->core.leader = &new_leader->core;
-            } else {
-                need_new_leader = false;
-                new_leader = NULL;
-            }
-        }
-    }
-
-    bitmap_free(evlist_removed);
-    free(nlist);
-}
-
  /**
   * parse_ids - Build the event string for the ids and parse them creating an
   *             evlist. The encoded metric_ids are decoded.
@@ -1521,18 +1319,14 @@ static void remove_pmu_umatched_events(struct evlist *evlist, char *metric_pmus)
   * @modifier: any modifiers added to the events.
   * @has_constraint: false if events should be placed in a weak group.
   * @out_evlist: the created list of events.
- * @pmu_name: the name of the CPU.
   */
  static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
               struct expr_parse_ctx *ids, const char *modifier,
-             bool has_constraint, struct evlist **out_evlist,
-             const char *pmu_name)
+             bool has_constraint, struct evlist **out_evlist)
  {
      struct parse_events_error parse_error;
      struct evlist *parsed_evlist;
      struct strbuf events = STRBUF_INIT;
-    struct strbuf metric_pmus = STRBUF_INIT;
-    char *nlist = NULL;
      int ret;
      *out_evlist = NULL;
@@ -1559,7 +1353,7 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
          ids__insert(ids->ids, tmp);
      }
      ret = metricgroup__build_event_string(&events, ids, modifier,
-                          has_constraint, pmu_name);
+                          has_constraint);
      if (ret)
          return ret;
@@ -1570,20 +1364,11 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
      }
      pr_debug("Parsing metric events '%s'\n", events.buf);
      parse_events_error__init(&parse_error);
-    nlist = get_metric_pmus(events.buf, &metric_pmus);
-    if (!nlist) {
-        ret = -ENOMEM;
-        goto err_out;
-    }
-    ret = __parse_events(parsed_evlist, nlist, &parse_error, fake_pmu);
+    ret = __parse_events(parsed_evlist, events.buf, &parse_error, fake_pmu);
      if (ret) {
          parse_events_error__print(&parse_error, events.buf);
          goto err_out;
      }
-
-    if (metric_pmus.alloc)
-        remove_pmu_umatched_events(parsed_evlist, metric_pmus.buf);
-
      ret = decode_all_metric_ids(parsed_evlist, modifier);
      if (ret)
          goto err_out;
@@ -1591,12 +1376,9 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
      *out_evlist = parsed_evlist;
      parsed_evlist = NULL;
  err_out:
-    if (nlist)
-        free(nlist);
      parse_events_error__exit(&parse_error);
      evlist__delete(parsed_evlist);
      strbuf_release(&events);
-    strbuf_release(&metric_pmus);
      return ret;
  }
@@ -1615,8 +1397,7 @@ static int parse_groups(struct evlist *perf_evlist, const char *str,
      if (metric_events_list->nr_entries == 0)
          metricgroup__rblist_init(metric_events_list);
      ret = metricgroup__add_metric_list(str, metric_no_group,
-                       &metric_list, map,
-                       perf_evlist->hybrid_pmu_name);
+                       &metric_list, map);
      if (ret)
          goto out;
@@ -1632,8 +1413,7 @@ static int parse_groups(struct evlist *perf_evlist, const char *str,
              ret = parse_ids(metric_no_merge, fake_pmu, combined,
                      /*modifier=*/NULL,
                      /*has_constraint=*/true,
-                    &combined_evlist,
-                    perf_evlist->hybrid_pmu_name);
+                    &combined_evlist);
          }
          if (combined)
              expr__ctx_free(combined);
@@ -1670,9 +1450,6 @@ static int parse_groups(struct evlist *perf_evlist, const char *str,
                      continue;
                  if (expr__subset_of_ids(n->pctx, m->pctx)) {
-                    if (m->pmu_name && n->pmu_name
-                        && strcmp(m->pmu_name, n->pmu_name))
-                        continue;
                      pr_debug("Events in '%s' fully contained within '%s'\n",
                           m->metric_name, n->metric_name);
                      metric_evlist = n->evlist;
@@ -1682,16 +1459,14 @@ static int parse_groups(struct evlist *perf_evlist, const char *str,
              }
          }
          if (!metric_evlist) {
-            ret = parse_ids(metric_no_merge, fake_pmu, m->pctx,
-                      m->modifier, m->has_constraint,
-                      &m->evlist, m->pmu_name);
+            ret = parse_ids(metric_no_merge, fake_pmu, m->pctx, m->modifier,
+                    m->has_constraint, &m->evlist);
              if (ret)
                  goto out;
              metric_evlist = m->evlist;
          }
-        ret = setup_metric_events(m->pctx->ids, metric_evlist,
-                      &metric_events, m->pmu_name);
+        ret = setup_metric_events(m->pctx->ids, metric_evlist, &metric_events);
          if (ret) {
              pr_debug("Cannot resolve IDs for %s: %s\n",
                  m->metric_name, m->metric_expr);
diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index 13f705737367..98669ca5a86b 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c
@@ -539,8 +539,7 @@ static void aggr_update_shadow(struct perf_stat_config *config,
      }
  }
-static void uniquify_event_name(struct evsel *counter,
-                struct perf_stat_config *stat_config)
+static void uniquify_event_name(struct evsel *counter)
  {
      char *new_name;
      char *config;
@@ -559,8 +558,7 @@ static void uniquify_event_name(struct evsel *counter,
              counter->name = new_name;
          }
      } else {
-        if (perf_pmu__has_hybrid() &&
-            stat_config->metric_events.nr_entries == 0) {
+        if (perf_pmu__has_hybrid()) {
              ret = asprintf(&new_name, "%s/%s/",
                         counter->pmu_name, counter->name);
          } else {
@@ -634,7 +632,7 @@ static bool collect_data(struct perf_stat_config *config, struct evsel *counter,
          return false;
      cb(config, counter, data, true);
      if (config->no_merge || hybrid_merge(counter, config, false))
-        uniquify_event_name(counter, config);
+        uniquify_event_name(counter);
      else if (counter->auto_merge_stats || hybrid_merge(counter, config, true))
          collect_all_aliases(config, counter, cb, data);
      return true;
--
2.36.0.512.ge40c2bad7a-goog


--
Zhengjun Xing