| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20180424191721.GB4427@kernel.org>
Date: Tue, 24 Apr 2018 16:17:21 -0300
From: Arnaldo Carvalho de Melo <acme@...nel.org>
To: kan.liang@...ux.intel.com
Cc: mingo@...hat.com, peterz@...radead.org,
linux-kernel@...r.kernel.org, jolsa@...hat.com,
namhyung@...nel.org, ganapatrao.kulkarni@...ium.com,
zhangshaokun@...ilicon.com, yao.jin@...ux.intel.com,
will.deacon@....com, ak@...ux.intel.com, agustinv@...eaurora.org
Subject: Re: [PATCH 4/5] perf parse-events: Specially handle uncore event
alias in small groups
Em Tue, Apr 24, 2018 at 11:20:13AM -0700, kan.liang@...ux.intel.com escreveu:
> From: Kan Liang <kan.liang@...ux.intel.com>
>
> Perf stat doesn't count the uncore event aliases from the same uncore
> block in a group, for example:
This one is not applying to acme/perf/urgent, all the rest I got merged
there, the last one with that change from using strstr() to a new bool
in perf_evsel for the uniquifying operation having being performed.
- Arnaldo
> perf stat -e '{unc_m_cas_count.all,unc_m_clockticks}' -a -I 1000
> # time counts unit events
> 1.000447342 <not counted> unc_m_cas_count.all
> 1.000447342 <not counted> unc_m_clockticks
> 2.000740654 <not counted> unc_m_cas_count.all
> 2.000740654 <not counted> 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 <ak@...ux.intel.com>
> Signed-off-by: Kan Liang <kan.liang@...ux.intel.com>
> ---
> tools/perf/util/evsel.h | 1 +
> tools/perf/util/parse-events.c | 94 ++++++++++++++++++++++++++++++++++++++++--
> tools/perf/util/parse-events.h | 7 +++-
> tools/perf/util/parse-events.y | 8 ++--
> 4 files changed, 101 insertions(+), 9 deletions(-)
>
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index d3ee3af..b8a1055 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -126,6 +126,7 @@ 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 2fb0272..7a836fe 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 +1324,7 @@ 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 +1346,85 @@ 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 (0 == strncmp(pmu_name_a, pmu_name_b, end_a - pmu_name_a));
> +}
> +
> +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;
> + int i = 0, nr_pmu = 0, total_members, ret = 0;
> +
> + leader = list_entry(list->next, struct perf_evsel, node);
> + evsel = list_entry(list->prev, struct perf_evsel, node);
> + total_members = evsel->idx - leader->idx + 1;
> +
> + leaders = calloc(total_members, sizeof(uintptr_t));
> + if (!leaders)
> + return ret;
> +
> + __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 (!strcmp(leader->name, evsel->name))
> + leaders[nr_pmu++] = (uintptr_t) evsel;
> + }
> +
> + /* only one event alias */
> + if (nr_pmu == total_members) {
> + parse_state->nr_groups--;
> + goto handled;
> + }
> +
> + __evlist__for_each_entry(list, evsel) {
> + if (i >= nr_pmu)
> + i = 0;
> + evsel->leader = (struct perf_evsel *) leaders[i++];
> + }
> +
> + 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;
> + }
> +
> + 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 +1433,9 @@ 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
Powered by blists - more mailing lists