perf pmu-events: Fix testing with JEVENTS_ARCH=all

The #slots literal will return NAN when not on ARM64 which causes a
perf test failure when not on an ARM64 for a JEVENTS_ARCH=all build:
..
 10.4: Parsing of PMU event table metrics with fake PMUs             : FAILED!
..
Add an is_test boolean so that the failure can be avoided when running
as a test.

Fixes: acef233b7c ("perf pmu: Add #slots literal support for arm64")
Reviewed-by: John Garry <[email protected]>
Reviewed-by: Kajol Jain <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Caleb Biggers <[email protected]>
Cc: Florian Fischer <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jing Zhang <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Kang Minchul <[email protected]>
Cc: Kim Phillips <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Perry Taylor <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Xing Zhengjun <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/tests/pmu-events.c

@@ -950,6 +950,7 @@ static int metric_parse_fake(const char *metric_name, const char *str)
 		pr_debug("expr__ctx_new failed");
 		return TEST_FAIL;
 	}
+	ctx->sctx.is_test = true;
 	if (expr__find_ids(str, NULL, ctx) < 0) {
 		pr_err("expr__find_ids failed\n");
 		return -1;

tools/perf/util/expr.h

@@ -9,6 +9,7 @@ struct expr_scanner_ctx {
 	char *user_requested_cpu_list;
 	int runtime;
 	bool system_wide;
+	bool is_test;
 };
 
 struct expr_parse_ctx {

tools/perf/util/expr.l

@@ -87,9 +87,11 @@ static int literal(yyscan_t scanner, const struct expr_scanner_ctx *sctx)
 	YYSTYPE *yylval = expr_get_lval(scanner);
 
 	yylval->num = expr__get_literal(expr_get_text(scanner), sctx);
-	if (isnan(yylval->num))
-		return EXPR_ERROR;
-
+	if (isnan(yylval->num)) {
+		if (!sctx->is_test)
+			return EXPR_ERROR;
+		yylval->num = 1;
+	}
 	return LITERAL;
 }
 %}