perf tools: Fix term parsing for raw syntax

Jin Yao reported issue with possible conflict between raw events and
term values in pmu event syntax.

Currently following syntax is resolved as raw event with 0xead value:

  uncore_imc_free_running/read/

instead of using 'read' term from uncore_imc_free_running pmu, because
'read' is correct raw event syntax with 0xead value.

To solve this issue we do following:

  - check existing terms during rXXXX syntax processing
    and make them priority in case of conflict

  - allow pmu/r0x1234/ syntax to be able to specify conflicting
    raw event (implemented in previous patch)

Also add automated tests for this and perf_pmu__parse_cleanup call to
parse_events_terms, so the test gets properly cleaned up.

Fixes: 3a6c51e4d6 ("perf parser: Add support to specify rXXX event with pmu")
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200726075244.1191481-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/parse-events.c

@@ -631,6 +631,34 @@ static int test__checkterms_simple(struct list_head *terms)
 	TEST_ASSERT_VAL("wrong val", term->val.num == 1);
 	TEST_ASSERT_VAL("wrong config", !strcmp(term->config, "umask"));
 
+	/*
+	 * read
+	 *
+	 * The perf_pmu__test_parse_init injects 'read' term into
+	 * perf_pmu_events_list, so 'read' is evaluated as read term
+	 * and not as raw event with 'ead' hex value.
+	 */
+	term = list_entry(term->list.next, struct parse_events_term, list);
+	TEST_ASSERT_VAL("wrong type term",
+			term->type_term == PARSE_EVENTS__TERM_TYPE_USER);
+	TEST_ASSERT_VAL("wrong type val",
+			term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
+	TEST_ASSERT_VAL("wrong val", term->val.num == 1);
+	TEST_ASSERT_VAL("wrong config", !strcmp(term->config, "read"));
+
+	/*
+	 * r0xead
+	 *
+	 * To be still able to pass 'ead' value with 'r' syntax,
+	 * we added support to parse 'r0xHEX' event.
+	 */
+	term = list_entry(term->list.next, struct parse_events_term, list);
+	TEST_ASSERT_VAL("wrong type term",
+			term->type_term == PARSE_EVENTS__TERM_TYPE_CONFIG);
+	TEST_ASSERT_VAL("wrong type val",
+			term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
+	TEST_ASSERT_VAL("wrong val", term->val.num == 0xead);
+	TEST_ASSERT_VAL("wrong config", !term->config);
 	return 0;
 }
 
@@ -1781,7 +1809,7 @@ struct terms_test {
 
 static struct terms_test test__terms[] = {
 	[0] = {
-		.str   = "config=10,config1,config2=3,umask=1",
+		.str   = "config=10,config1,config2=3,umask=1,read,r0xead",
 		.check = test__checkterms_simple,
 	},
 };
@@ -1841,6 +1869,13 @@ static int test_term(struct terms_test *t)
 
 	INIT_LIST_HEAD(&terms);
 
+	/*
+	 * The perf_pmu__test_parse_init prepares perf_pmu_events_list
+	 * which gets freed in parse_events_terms.
+	 */
+	if (perf_pmu__test_parse_init())
+		return -1;
+
 	ret = parse_events_terms(&terms, t->str);
 	if (ret) {
 		pr_debug("failed to parse terms '%s', err %d\n",

tools/perf/util/parse-events.c

@@ -2019,6 +2019,32 @@ static void perf_pmu__parse_init(void)
 	perf_pmu__parse_cleanup();
 }
 
+/*
+ * This function injects special term in
+ * perf_pmu_events_list so the test code
+ * can check on this functionality.
+ */
+int perf_pmu__test_parse_init(void)
+{
+	struct perf_pmu_event_symbol *list;
+
+	list = malloc(sizeof(*list) * 1);
+	if (!list)
+		return -ENOMEM;
+
+	list->type   = PMU_EVENT_SYMBOL;
+	list->symbol = strdup("read");
+
+	if (!list->symbol) {
+		free(list);
+		return -ENOMEM;
+	}
+
+	perf_pmu_events_list = list;
+	perf_pmu_events_list_num = 1;
+	return 0;
+}
+
 enum perf_pmu_event_symbol_type
 perf_pmu__parse_check(const char *name)
 {
@@ -2080,6 +2106,8 @@ int parse_events_terms(struct list_head *terms, const char *str)
 	int ret;
 
 	ret = parse_events__scanner(str, &parse_state);
+	perf_pmu__parse_cleanup();
+
 	if (!ret) {
 		list_splice(parse_state.terms, terms);
 		zfree(&parse_state.terms);

tools/perf/util/parse-events.h

@@ -261,4 +261,6 @@ static inline bool is_sdt_event(char *str __maybe_unused)
 }
 #endif /* HAVE_LIBELF_SUPPORT */
 
+int perf_pmu__test_parse_init(void);
+
 #endif /* __PERF_PARSE_EVENTS_H */

tools/perf/util/parse-events.l

@@ -41,14 +41,6 @@ static int value(yyscan_t scanner, int base)
 	return __value(yylval, text, base, PE_VALUE);
 }
 
-static int raw(yyscan_t scanner)
-{
-	YYSTYPE *yylval = parse_events_get_lval(scanner);
-	char *text = parse_events_get_text(scanner);
-
-	return __value(yylval, text + 1, 16, PE_RAW);
-}
-
 static int str(yyscan_t scanner, int token)
 {
 	YYSTYPE *yylval = parse_events_get_lval(scanner);
@@ -72,6 +64,17 @@ static int str(yyscan_t scanner, int token)
 	return token;
 }
 
+static int raw(yyscan_t scanner)
+{
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+	char *text = parse_events_get_text(scanner);
+
+	if (perf_pmu__parse_check(text) == PMU_EVENT_SYMBOL)
+		return str(scanner, PE_NAME);
+
+	return __value(yylval, text + 1, 16, PE_RAW);
+}
+
 static bool isbpf_suffix(char *text)
 {
 	int len = strlen(text);