perf parse-events: Avoid error when assigning a term

Avoid the parser error:
'''
$ perf stat -e 'cycles/name=name/' true
event syntax error: 'cycles/name=name/'
                                \___ parser error
'''
by turning the term back to a string if it is on the right. Add PMU
and generic parsing tests.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahmad Yasin <ahmad.yasin@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Florian Fischer <florian.fischer@muhq.space>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kang Minchul <tegongkang@gmail.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Samantha Alt <samantha.alt@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20230502223851.2234828-35-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/parse-events.c

@@ -1499,6 +1499,16 @@ static int test__sym_event_dc(struct evlist *evlist)
 	return TEST_OK;
 }
 
+static int test__term_equal_term(struct evlist *evlist)
+{
+	struct evsel *evsel = evlist__first(evlist);
+
+	TEST_ASSERT_VAL("wrong type", evsel->core.attr.type == PERF_TYPE_HARDWARE);
+	TEST_ASSERT_VAL("wrong config", test_config(evsel, PERF_COUNT_HW_CPU_CYCLES));
+	TEST_ASSERT_VAL("wrong name setting", strcmp(evsel->name, "name") == 0);
+	return TEST_OK;
+}
+
 #ifdef HAVE_LIBTRACEEVENT
 static int count_tracepoints(void)
 {
@@ -1871,6 +1881,11 @@ static const struct evlist_test test__events[] = {
 		.check = test__exclusive_group,
 		/* 7 */
 	},
+	{
+		.name  = "cycles/name=name/",
+		.check = test__term_equal_term,
+		/* 8 */
+	},
 };
 
 static const struct evlist_test test__events_pmu[] = {
@@ -2052,6 +2067,12 @@ static const struct evlist_test test__events_pmu[] = {
 		.check = test__exclusive_group,
 		/* 9 */
 	},
+	{
+		.name  = "cpu/cycles,name=name/",
+		.valid = test__pmu_cpu_valid,
+		.check = test__term_equal_term,
+		/* 0 */
+	},
 };
 
 struct terms_test {

tools/perf/util/parse-events.c

@@ -2581,6 +2581,15 @@ int parse_events_term__str(struct parse_events_term **term,
 	return new_term(term, &temp, str, 0);
 }
 
+int parse_events_term__term(struct parse_events_term **term,
+			    int term_lhs, int term_rhs,
+			    void *loc_term, void *loc_val)
+{
+	return parse_events_term__str(term, term_lhs, NULL,
+				      strdup(config_term_names[term_rhs]),
+				      loc_term, loc_val);
+}
+
 int parse_events_term__clone(struct parse_events_term **new,
 			     struct parse_events_term *term)
 {

tools/perf/util/parse-events.h

@@ -148,6 +148,9 @@ int parse_events_term__num(struct parse_events_term **term,
 int parse_events_term__str(struct parse_events_term **term,
 			   int type_term, char *config, char *str,
 			   void *loc_term, void *loc_val);
+int parse_events_term__term(struct parse_events_term **term,
+			    int term_lhs, int term_rhs,
+			    void *loc_term, void *loc_val);
 int parse_events_term__clone(struct parse_events_term **new,
 			     struct parse_events_term *term);
 void parse_events_term__delete(struct parse_events_term *term);

tools/perf/util/parse-events.y

@@ -848,6 +848,14 @@ PE_TERM '=' PE_TERM_HW
 	$$ = term;
 }
 |
+PE_TERM '=' PE_TERM
+{
+	struct parse_events_term *term;
+
+	ABORT_ON(parse_events_term__term(&term, (int)$1, (int)$3, &@1, &@3));
+	$$ = term;
+}
+|
 PE_TERM '=' PE_VALUE
 {
 	struct parse_events_term *term;