[PATCH v1 20/40] perf parse-events: Support PMUs for legacy cache events

From: Ian Rogers
Date: Wed Apr 26 2023 - 03:05:30 EST


Allow a legacy cache event to be both, for example,
"L1-dcache-load-miss" and "cpu/L1-dcache-load-miss/" by introducing a
new legacy cache term type. The term type is processed in
config_term_pmu, setting both the type in perf_event_attr and the
config. The code to determine the config is factored out of
parse_events_add_cache and shared. If the PMU doesn't support legacy
events, currently just core/hybrid PMUs do, then the term is treated
like a PE_NAME term - as before. If only terms are being parsed, such
as for perf_pmu__new_alias, then the PE_LEGACY_CACHE token is always
parsed as PE_NAME.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/tests/parse-events.c | 18 +++++++++
tools/perf/util/parse-events.c | 70 ++++++++++++++++++++++-----------
tools/perf/util/parse-events.h | 3 ++
tools/perf/util/parse-events.l | 9 ++++-
tools/perf/util/parse-events.y | 14 ++++++-
tools/perf/util/pmu.c | 5 +++
tools/perf/util/pmu.h | 1 +
7 files changed, 96 insertions(+), 24 deletions(-)

diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index 15fec7f01315..6aea51e33dc0 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -1861,6 +1861,24 @@ static const struct evlist_test test__events_pmu[] = {
.check = test__checkevent_raw_pmu,
/* 5 */
},
+ {
+ .name = "cpu/L1-dcache-load-miss/",
+ .valid = test__pmu_cpu_valid,
+ .check = test__checkevent_genhw,
+ /* 6 */
+ },
+ {
+ .name = "cpu/L1-dcache-load-miss/kp",
+ .valid = test__pmu_cpu_valid,
+ .check = test__checkevent_genhw_modifier,
+ /* 7 */
+ },
+ {
+ .name = "cpu/L1-dcache-misses,name=cachepmu/",
+ .valid = test__pmu_cpu_valid,
+ .check = test__checkevent_config_cache,
+ /* 8 */
+ },
};

struct terms_test {
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index e416e653cf74..9b2d7b6572c2 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -403,33 +403,27 @@ static int config_attr(struct perf_event_attr *attr,
struct parse_events_error *err,
config_term_func_t config_term);

-int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
- struct parse_events_error *err,
- struct list_head *head_config,
- struct parse_events_state *parse_state)
+/**
+ * parse_events__decode_legacy_cache - Search name for the legacy cache event
+ * name composed of 1, 2 or 3 hyphen
+ * separated sections. The first section is
+ * the cache type while the others are the
+ * optional op and optional result. To make
+ * life hard the names in the table also
+ * contain hyphens and the longest name
+ * should always be selected.
+ */
+static int parse_events__decode_legacy_cache(const char *name, int pmu_type, __u64 *config)
{
- struct perf_event_attr attr;
- LIST_HEAD(config_terms);
- const char *config_name, *metric_id;
- int cache_type = -1, cache_op = -1, cache_result = -1;
- int ret, len;
+ int len, cache_type = -1, cache_op = -1, cache_result = -1;
const char *name_end = &name[strlen(name) + 1];
- bool hybrid;
const char *str = name;

- /*
- * Search str for the legacy cache event name composed of 1, 2 or 3
- * hyphen separated sections. The first section is the cache type while
- * the others are the optional op and optional result. To make life hard
- * the names in the table also contain hyphens and the longest name
- * should always be selected.
- */
cache_type = parse_aliases(str, evsel__hw_cache, PERF_COUNT_HW_CACHE_MAX, &len);
if (cache_type == -1)
return -EINVAL;
str += len + 1;

- config_name = get_config_name(head_config);
if (str < name_end) {
cache_op = parse_aliases(str, evsel__hw_cache_op,
PERF_COUNT_HW_CACHE_OP_MAX, &len);
@@ -470,9 +464,28 @@ int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
if (cache_result == -1)
cache_result = PERF_COUNT_HW_CACHE_RESULT_ACCESS;

+ *config = ((__u64)pmu_type << PERF_PMU_TYPE_SHIFT) |
+ cache_type | (cache_op << 8) | (cache_result << 16);
+ return 0;
+}
+
+int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
+ struct parse_events_error *err,
+ struct list_head *head_config,
+ struct parse_events_state *parse_state)
+{
+ struct perf_event_attr attr;
+ LIST_HEAD(config_terms);
+ const char *config_name, *metric_id;
+ int ret;
+ bool hybrid;
+
+
memset(&attr, 0, sizeof(attr));
- attr.config = cache_type | (cache_op << 8) | (cache_result << 16);
attr.type = PERF_TYPE_HW_CACHE;
+ ret = parse_events__decode_legacy_cache(name, /*pmu_type=*/0, &attr.config);
+ if (ret)
+ return ret;

if (head_config) {
if (config_attr(&attr, head_config, err,
@@ -483,6 +496,7 @@ int parse_events_add_cache(struct list_head *list, int *idx, const char *name,
return -ENOMEM;
}

+ config_name = get_config_name(head_config);
metric_id = get_config_metric_id(head_config);
ret = parse_events__add_cache_hybrid(list, idx, &attr,
config_name ? : name,
@@ -1021,6 +1035,7 @@ static const char *config_term_names[__PARSE_EVENTS__TERM_TYPE_NR] = {
[PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE] = "aux-sample-size",
[PARSE_EVENTS__TERM_TYPE_METRIC_ID] = "metric-id",
[PARSE_EVENTS__TERM_TYPE_RAW] = "raw",
+ [PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE] = "legacy-cache",
};

static bool config_term_shrinked;
@@ -1198,15 +1213,25 @@ static int config_term_pmu(struct perf_event_attr *attr,
struct parse_events_term *term,
struct parse_events_error *err)
{
+ if (term->type_term == PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE) {
+ const struct perf_pmu *pmu = perf_pmu__find_by_type(attr->type);
+
+ if (perf_pmu__supports_legacy_cache(pmu)) {
+ attr->type = PERF_TYPE_HW_CACHE;
+ return parse_events__decode_legacy_cache(term->config, pmu->type,
+ &attr->config);
+ } else
+ term->type_term = PARSE_EVENTS__TERM_TYPE_USER;
+ }
if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER ||
- term->type_term == PARSE_EVENTS__TERM_TYPE_DRV_CFG)
+ term->type_term == PARSE_EVENTS__TERM_TYPE_DRV_CFG) {
/*
* Always succeed for sysfs terms, as we dont know
* at this point what type they need to have.
*/
return 0;
- else
- return config_term_common(attr, term, err);
+ }
+ return config_term_common(attr, term, err);
}

#ifdef HAVE_LIBTRACEEVENT
@@ -2145,6 +2170,7 @@ int __parse_events(struct evlist *evlist, const char *str,
.evlist = evlist,
.stoken = PE_START_EVENTS,
.fake_pmu = fake_pmu,
+ .match_legacy_cache_terms = true,
};
int ret;

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index f638542c8638..5acb62c2e00a 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -71,6 +71,7 @@ enum {
PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE,
PARSE_EVENTS__TERM_TYPE_METRIC_ID,
PARSE_EVENTS__TERM_TYPE_RAW,
+ PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE,
__PARSE_EVENTS__TERM_TYPE_NR,
};

@@ -122,6 +123,8 @@ struct parse_events_state {
int stoken;
struct perf_pmu *fake_pmu;
char *hybrid_pmu_name;
+ /* Should PE_LEGACY_NAME tokens be generated for config terms? */
+ bool match_legacy_cache_terms;
bool wild_card_pmus;
};

diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 4b35c099189a..abe0ce681d29 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -63,6 +63,11 @@ static int str(yyscan_t scanner, int token)
return token;
}

+static int lc_str(yyscan_t scanner, const struct parse_events_state *state)
+{
+ return str(scanner, state->match_legacy_cache_terms ? PE_LEGACY_CACHE : PE_NAME);
+}
+
static bool isbpf_suffix(char *text)
{
int len = strlen(text);
@@ -185,7 +190,6 @@ lc_op_result (load|loads|read|store|stores|write|prefetch|prefetches|speculative

%{
struct parse_events_state *_parse_state = parse_events_get_extra(yyscanner);
-
{
int start_token = _parse_state->stoken;

@@ -269,6 +273,9 @@ r{num_raw_hex} { return str(yyscanner, PE_RAW); }
r0x{num_raw_hex} { return str(yyscanner, PE_RAW); }
, { return ','; }
"/" { BEGIN(INITIAL); return '/'; }
+{lc_type} { return lc_str(yyscanner, _parse_state); }
+{lc_type}-{lc_op_result} { return lc_str(yyscanner, _parse_state); }
+{lc_type}-{lc_op_result}-{lc_op_result} { return lc_str(yyscanner, _parse_state); }
{name_minus} { return str(yyscanner, PE_NAME); }
\[all\] { return PE_ARRAY_ALL; }
"[" { BEGIN(array); return '['; }
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index e7072b5601c5..f84fa1b132b3 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -723,7 +723,7 @@ event_term
$$ = head;
}

-name_or_raw: PE_RAW | PE_NAME
+name_or_raw: PE_RAW | PE_NAME | PE_LEGACY_CACHE

event_term:
PE_RAW
@@ -775,6 +775,18 @@ name_or_raw '=' PE_VALUE_SYM_HW
$$ = term;
}
|
+PE_LEGACY_CACHE
+{
+ struct parse_events_term *term;
+
+ if (parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE,
+ $1, 1, true, &@1, NULL)) {
+ free($1);
+ YYABORT;
+ }
+ $$ = term;
+}
+|
PE_NAME
{
struct parse_events_term *term;
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index cb33d869f1ed..63071d876190 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -1650,6 +1650,11 @@ bool is_pmu_core(const char *name)
return !strcmp(name, "cpu") || is_arm_pmu_core(name);
}

+bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu)
+{
+ return is_pmu_core(pmu->name) || perf_pmu__is_hybrid(pmu->name);
+}
+
static bool pmu_alias_is_duplicate(struct sevent *alias_a,
struct sevent *alias_b)
{
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index b9a02dedd473..05702bc4bcf8 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -220,6 +220,7 @@ void perf_pmu__del_formats(struct list_head *formats);
struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu);

bool is_pmu_core(const char *name);
+bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu);
void print_pmu_events(const struct print_callbacks *print_cb, void *print_state);
bool pmu_have_event(const char *pname, const char *name);

--
2.40.1.495.gc816e09b53d-goog