perf expr: Make expr__parse() return -1 on error

To match the error value of the expr__find_other function, so all
exported expr functions return the same values:
0 on success, -1 on error.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-6-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/expr.c

@@ -45,11 +45,11 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
 
 	p = "FOO/0";
 	ret = expr__parse(&val, &ctx, p);
-	TEST_ASSERT_VAL("division by zero", ret == 1);
+	TEST_ASSERT_VAL("division by zero", ret == -1);
 
 	p = "BAR/";
 	ret = expr__parse(&val, &ctx, p);
-	TEST_ASSERT_VAL("missing operand", ret == 1);
+	TEST_ASSERT_VAL("missing operand", ret == -1);
 
 	TEST_ASSERT_VAL("find other",
 			expr__find_other("FOO + BAR + BAZ + BOZO", "FOO", &other, &num_other) == 0);

tools/perf/util/expr.c

@@ -54,7 +54,7 @@ __expr__parse(double *val, struct parse_ctx *ctx, const char *expr,
 
 int expr__parse(double *final_val, struct parse_ctx *ctx, const char *expr)
 {
-	return __expr__parse(final_val, ctx, expr, EXPR_PARSE);
+	return __expr__parse(final_val, ctx, expr, EXPR_PARSE) ? -1 : 0;
 }
 
 static bool