From 369b230806a9f3ff691466d54795e5e3ff3f8f5c Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Mon, 7 May 2018 14:13:43 -0700 Subject: [PATCH] perf parse-events: Handle uncore event aliases in small groups properly Perf stat doesn't count the uncore event aliases from the same uncore block in a group, for example: perf stat -e '{unc_m_cas_count.all,unc_m_clockticks}' -a -I 1000 # time counts unit events 1.000447342 unc_m_cas_count.all 1.000447342 unc_m_clockticks 2.000740654 unc_m_cas_count.all 2.000740654 unc_m_clockticks The output is very misleading. It gives a wrong impression that the uncore event doesn't work. An uncore block could be composed by several PMUs. An uncore event alias is a joint name which means the same event runs on all PMUs of a block. Perf doesn't support mixed events from different PMUs in the same group. It is wrong to put uncore event aliases in a big group. The right way is to split the big group into multiple small groups which only include the events from the same PMU. Only uncore event aliases from the same uncore block should be specially handled here. It doesn't make sense to mix the uncore events with other uncore events from different blocks or even core events in a group. With the patch: # time counts unit events 1.001557653 140,833 unc_m_cas_count.all 1.001557653 1,330,231,332 unc_m_clockticks 2.002709483 85,007 unc_m_cas_count.all 2.002709483 1,429,494,563 unc_m_clockticks Reported-by: Andi Kleen Signed-off-by: Kan Liang Acked-by: Jiri Olsa Cc: Agustin Vega-Frias Cc: Ganapatrao Kulkarni Cc: Jin Yao Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Shaokun Zhang Cc: Will Deacon Link: http://lkml.kernel.org/r/1525727623-19768-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evsel.h | 1 + tools/perf/util/parse-events.c | 130 ++++++++++++++++++++++++++++++++++++++++- tools/perf/util/parse-events.h | 7 ++- tools/perf/util/parse-events.y | 8 +-- 4 files changed, 137 insertions(+), 9 deletions(-) diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index 92ec009..b13f5f2 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -127,6 +127,7 @@ struct perf_evsel { bool precise_max; bool ignore_missing_thread; bool forced_leader; + bool use_uncore_alias; /* parse modifier helper */ int exclude_GH; int nr_members; diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index b8b8a95..2fc4ee8 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -1219,13 +1219,16 @@ int parse_events_add_numeric(struct parse_events_state *parse_state, int parse_events_add_pmu(struct parse_events_state *parse_state, struct list_head *list, char *name, - struct list_head *head_config, bool auto_merge_stats) + struct list_head *head_config, + bool auto_merge_stats, + bool use_alias) { struct perf_event_attr attr; struct perf_pmu_info info; struct perf_pmu *pmu; struct perf_evsel *evsel; struct parse_events_error *err = parse_state->error; + bool use_uncore_alias; LIST_HEAD(config_terms); pmu = perf_pmu__find(name); @@ -1244,11 +1247,14 @@ int parse_events_add_pmu(struct parse_events_state *parse_state, memset(&attr, 0, sizeof(attr)); } + use_uncore_alias = (pmu->is_uncore && use_alias); + if (!head_config) { attr.type = pmu->type; evsel = __add_event(list, &parse_state->idx, &attr, NULL, pmu, NULL, auto_merge_stats); if (evsel) { evsel->pmu_name = name; + evsel->use_uncore_alias = use_uncore_alias; return 0; } else { return -ENOMEM; @@ -1282,6 +1288,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state, evsel->metric_expr = info.metric_expr; evsel->metric_name = info.metric_name; evsel->pmu_name = name; + evsel->use_uncore_alias = use_uncore_alias; } return evsel ? 0 : -ENOMEM; @@ -1317,7 +1324,8 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state, list_add_tail(&term->list, head); if (!parse_events_add_pmu(parse_state, list, - pmu->name, head, true)) { + pmu->name, head, + true, true)) { pr_debug("%s -> %s/%s/\n", str, pmu->name, alias->str); ok++; @@ -1339,7 +1347,120 @@ int parse_events__modifier_group(struct list_head *list, return parse_events__modifier_event(list, event_mod, true); } -void parse_events__set_leader(char *name, struct list_head *list) +/* + * Check if the two uncore PMUs are from the same uncore block + * The format of the uncore PMU name is uncore_#blockname_#pmuidx + */ +static bool is_same_uncore_block(const char *pmu_name_a, const char *pmu_name_b) +{ + char *end_a, *end_b; + + end_a = strrchr(pmu_name_a, '_'); + end_b = strrchr(pmu_name_b, '_'); + + if (!end_a || !end_b) + return false; + + if ((end_a - pmu_name_a) != (end_b - pmu_name_b)) + return false; + + return (strncmp(pmu_name_a, pmu_name_b, end_a - pmu_name_a) == 0); +} + +static int +parse_events__set_leader_for_uncore_aliase(char *name, struct list_head *list, + struct parse_events_state *parse_state) +{ + struct perf_evsel *evsel, *leader; + uintptr_t *leaders; + bool is_leader = true; + int i, nr_pmu = 0, total_members, ret = 0; + + leader = list_first_entry(list, struct perf_evsel, node); + evsel = list_last_entry(list, struct perf_evsel, node); + total_members = evsel->idx - leader->idx + 1; + + leaders = calloc(total_members, sizeof(uintptr_t)); + if (WARN_ON(!leaders)) + return 0; + + /* + * Going through the whole group and doing sanity check. + * All members must use alias, and be from the same uncore block. + * Also, storing the leader events in an array. + */ + __evlist__for_each_entry(list, evsel) { + + /* Only split the uncore group which members use alias */ + if (!evsel->use_uncore_alias) + goto out; + + /* The events must be from the same uncore block */ + if (!is_same_uncore_block(leader->pmu_name, evsel->pmu_name)) + goto out; + + if (!is_leader) + continue; + /* + * If the event's PMU name starts to repeat, it must be a new + * event. That can be used to distinguish the leader from + * other members, even they have the same event name. + */ + if ((leader != evsel) && (leader->pmu_name == evsel->pmu_name)) { + is_leader = false; + continue; + } + /* The name is always alias name */ + WARN_ON(strcmp(leader->name, evsel->name)); + + /* Store the leader event for each PMU */ + leaders[nr_pmu++] = (uintptr_t) evsel; + } + + /* only one event alias */ + if (nr_pmu == total_members) { + parse_state->nr_groups--; + goto handled; + } + + /* + * An uncore event alias is a joint name which means the same event + * runs on all PMUs of a block. + * Perf doesn't support mixed events from different PMUs in the same + * group. The big group has to be split into multiple small groups + * which only include the events from the same PMU. + * + * Here the uncore event aliases must be from the same uncore block. + * The number of PMUs must be same for each alias. The number of new + * small groups equals to the number of PMUs. + * Setting the leader event for corresponding members in each group. + */ + i = 0; + __evlist__for_each_entry(list, evsel) { + if (i >= nr_pmu) + i = 0; + evsel->leader = (struct perf_evsel *) leaders[i++]; + } + + /* The number of members and group name are same for each group */ + for (i = 0; i < nr_pmu; i++) { + evsel = (struct perf_evsel *) leaders[i]; + evsel->nr_members = total_members / nr_pmu; + evsel->group_name = name ? strdup(name) : NULL; + } + + /* Take the new small groups into account */ + parse_state->nr_groups += nr_pmu - 1; + +handled: + ret = 1; +out: + free(leaders); + return ret; +} + +void parse_events__set_leader(char *name, struct list_head *list, + struct parse_events_state *parse_state) { struct perf_evsel *leader; @@ -1348,6 +1469,9 @@ void parse_events__set_leader(char *name, struct list_head *list) return; } + if (parse_events__set_leader_for_uncore_aliase(name, list, parse_state)) + return; + __perf_evlist__set_leader(list); leader = list_entry(list->next, struct perf_evsel, node); leader->group_name = name ? strdup(name) : NULL; diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h index 5015cfd..4473dac 100644 --- a/tools/perf/util/parse-events.h +++ b/tools/perf/util/parse-events.h @@ -167,7 +167,9 @@ int parse_events_add_breakpoint(struct list_head *list, int *idx, void *ptr, char *type, u64 len); int parse_events_add_pmu(struct parse_events_state *parse_state, struct list_head *list, char *name, - struct list_head *head_config, bool auto_merge_stats); + struct list_head *head_config, + bool auto_merge_stats, + bool use_alias); int parse_events_multi_pmu_add(struct parse_events_state *parse_state, char *str, @@ -178,7 +180,8 @@ int parse_events_copy_term_list(struct list_head *old, enum perf_pmu_event_symbol_type perf_pmu__parse_check(const char *name); -void parse_events__set_leader(char *name, struct list_head *list); +void parse_events__set_leader(char *name, struct list_head *list, + struct parse_events_state *parse_state); void parse_events_update_lists(struct list_head *list_event, struct list_head *list_all); void parse_events_evlist_error(struct parse_events_state *parse_state, diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y index 7afeb80..e37608a 100644 --- a/tools/perf/util/parse-events.y +++ b/tools/perf/util/parse-events.y @@ -161,7 +161,7 @@ PE_NAME '{' events '}' struct list_head *list = $3; inc_group_count(list, _parse_state); - parse_events__set_leader($1, list); + parse_events__set_leader($1, list, _parse_state); $$ = list; } | @@ -170,7 +170,7 @@ PE_NAME '{' events '}' struct list_head *list = $2; inc_group_count(list, _parse_state); - parse_events__set_leader(NULL, list); + parse_events__set_leader(NULL, list, _parse_state); $$ = list; } @@ -232,7 +232,7 @@ PE_NAME opt_event_config YYABORT; ALLOC_LIST(list); - if (parse_events_add_pmu(_parse_state, list, $1, $2, false)) { + if (parse_events_add_pmu(_parse_state, list, $1, $2, false, false)) { struct perf_pmu *pmu = NULL; int ok = 0; char *pattern; @@ -251,7 +251,7 @@ PE_NAME opt_event_config free(pattern); YYABORT; } - if (!parse_events_add_pmu(_parse_state, list, pmu->name, terms, true)) + if (!parse_events_add_pmu(_parse_state, list, pmu->name, terms, true, false)) ok++; parse_events_terms__delete(terms); } -- 2.7.4