[PATCH 04/14] perf tools: Add fake pmu support

From: Jiri Olsa
Date: Sun May 24 2020 - 18:43:06 EST


Adding the way to create pmu event without the actual
PMU being in place. This way we can test metrics defined
for any processors.

The interface is to define fake_pmu in struct parse_events_state
data. It will be used only in tests via special interface
function added in following changes.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/util/parse-events.c | 14 ++++++++++---
tools/perf/util/parse-events.h | 3 ++-
tools/perf/util/parse-events.l | 8 ++++++--
tools/perf/util/parse-events.y | 37 ++++++++++++++++++++++++++++++++--
4 files changed, 54 insertions(+), 8 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 27b8e49d690e..8304f9b6e6be 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1415,6 +1415,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
bool auto_merge_stats,
bool use_alias)
{
+ bool is_fake = parse_state->fake_pmu;
struct perf_event_attr attr;
struct perf_pmu_info info;
struct perf_pmu *pmu;
@@ -1436,7 +1437,14 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
fprintf(stderr, "' that may result in non-fatal errors\n");
}

- pmu = perf_pmu__find(name);
+ if (is_fake) {
+ static struct perf_pmu fake_pmu = { };
+
+ pmu = &fake_pmu;
+ } else {
+ pmu = perf_pmu__find(name);
+ }
+
if (!pmu) {
char *err_str;

@@ -1469,7 +1477,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
}
}

- if (perf_pmu__check_alias(pmu, head_config, &info))
+ if (!is_fake && perf_pmu__check_alias(pmu, head_config, &info))
return -EINVAL;

if (verbose > 1) {
@@ -1502,7 +1510,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
if (pmu->default_config && get_config_chgs(pmu, head_config, &config_terms))
return -ENOMEM;

- if (perf_pmu__config(pmu, &attr, head_config, parse_state->error)) {
+ if (!is_fake && perf_pmu__config(pmu, &attr, head_config, parse_state->error)) {
struct evsel_config_term *pos, *tmp;

list_for_each_entry_safe(pos, tmp, &config_terms, list) {
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index d60510e0609f..963b0ea6c448 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -126,9 +126,10 @@ struct parse_events_state {
int idx;
int nr_groups;
struct parse_events_error *error;
- struct evlist *evlist;
+ struct evlist *evlist;
struct list_head *terms;
int stoken;
+ bool fake_pmu;
};

void parse_events__handle_error(struct parse_events_error *err, int idx,
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 002802e17059..56912c9641f5 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -129,12 +129,16 @@ do { \
yyless(0); \
} while (0)

-static int pmu_str_check(yyscan_t scanner)
+static int pmu_str_check(yyscan_t scanner, struct parse_events_state *parse_state)
{
YYSTYPE *yylval = parse_events_get_lval(scanner);
char *text = parse_events_get_text(scanner);

yylval->str = strdup(text);
+
+ if (parse_state->fake_pmu)
+ return PE_PMU_EVENT_FAKE;
+
switch (perf_pmu__parse_check(text)) {
case PMU_EVENT_SYMBOL_PREFIX:
return PE_PMU_EVENT_PRE;
@@ -376,7 +380,7 @@ r{num_raw_hex} { return raw(yyscanner); }
{modifier_event} { return str(yyscanner, PE_MODIFIER_EVENT); }
{bpf_object} { if (!isbpf(yyscanner)) { USER_REJECT }; return str(yyscanner, PE_BPF_OBJECT); }
{bpf_source} { if (!isbpf(yyscanner)) { USER_REJECT }; return str(yyscanner, PE_BPF_SOURCE); }
-{name} { return pmu_str_check(yyscanner); }
+{name} { return pmu_str_check(yyscanner, _parse_state); }
{name_tag} { return str(yyscanner, PE_NAME); }
"/" { BEGIN(config); return '/'; }
- { return '-'; }
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index c4ca932d092d..d1b04b8d81ea 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -69,7 +69,7 @@ static void inc_group_count(struct list_head *list,
%token PE_NAME_CACHE_TYPE PE_NAME_CACHE_OP_RESULT
%token PE_PREFIX_MEM PE_PREFIX_RAW PE_PREFIX_GROUP
%token PE_ERROR
-%token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
+%token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
%token PE_ARRAY_ALL PE_ARRAY_RANGE
%token PE_DRV_CFG_TERM
%type <num> PE_VALUE
@@ -87,7 +87,7 @@ static void inc_group_count(struct list_head *list,
%type <str> PE_MODIFIER_EVENT
%type <str> PE_MODIFIER_BP
%type <str> PE_EVENT_NAME
-%type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
+%type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
%type <str> PE_DRV_CFG_TERM
%destructor { free ($$); } <str>
%type <term> event_term
@@ -356,6 +356,39 @@ PE_PMU_EVENT_PRE '-' PE_PMU_EVENT_SUF sep_dc
YYABORT;
$$ = list;
}
+|
+PE_PMU_EVENT_FAKE sep_dc
+{
+ struct list_head *list;
+ int err;
+
+ list = alloc_list();
+ if (!list)
+ YYABORT;
+
+ err = parse_events_add_pmu(_parse_state, list, $1, NULL, false, false);
+ free($1);
+ if (err < 0)
+ YYABORT;
+ $$ = list;
+}
+|
+PE_PMU_EVENT_FAKE opt_pmu_config
+{
+ struct list_head *list;
+ int err;
+
+ list = alloc_list();
+ if (!list)
+ YYABORT;
+
+ err = parse_events_add_pmu(_parse_state, list, $1, $2, false, false);
+ free($1);
+ parse_events_terms__delete($2);
+ if (err < 0)
+ YYABORT;
+ $$ = list;
+}

value_sym:
PE_VALUE_SYM_HW
--
2.25.4