[PATCH bpf v5] selftests: arg_parsing: Ensure data is flushed to disk before reading.

[Xing Guo <higuoxing@gmail.com>]

test_parse_test_list_file writes some data to
/tmp/bpf_arg_parsing_test.XXXXXX and parse_test_list_file() will read
the data back.  However, after writing data to that file, we forget to
call fsync() and it's causing testing failure in my laptop.  This patch
helps fix it by adding the missing fsync() call.

Signed-off-by: Xing Guo <higuoxing@gmail.com>
---
 tools/testing/selftests/bpf/prog_tests/arg_parsing.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/arg_parsing.c b/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
index fbf0d9c2f58b..e27d66b75fb1 100644
--- a/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
+++ b/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
@@ -144,6 +144,9 @@ static void test_parse_test_list_file(void)
 	if (!ASSERT_OK(ferror(fp), "prepare tmp"))
 		goto out_fclose;
 
+	if (!ASSERT_OK(fsync(fileno(fp)), "fsync tmp"))
+		goto out_fclose;
+
 	init_test_filter_set(&set);
 
 	if (!ASSERT_OK(parse_test_list_file(tmpfile, &set, true), "parse file"))
-- 
2.51.0