[RFC PATCH 2/2] selftests: restrictedmem: Add selftest for RMFD_HUGEPAGE

[Ackerley Tng]

Tests that when RMFD_HUGEPAGE is specified, restrictedmem will be
backed by Transparent HugePages.

Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 .../restrictedmem_hugepage_test.c             | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git 
a/tools/testing/selftests/restrictedmem/restrictedmem_hugepage_test.c 
b/tools/testing/selftests/restrictedmem/restrictedmem_hugepage_test.c
index 0d9cf2ced754..75283d68696f 100644
--- a/tools/testing/selftests/restrictedmem/restrictedmem_hugepage_test.c
+++ b/tools/testing/selftests/restrictedmem/restrictedmem_hugepage_test.c
@@ -180,6 +180,31 @@ TEST_F(reset_shmem_enabled, 
restrictedmem_fstat_shmem_enabled_always)
        close(mfd);
 }
 
+TEST(restrictedmem_invalid_flags)
+{
+       int mfd = memfd_restricted(99, NULL);
+
+       ASSERT_EQ(-1, mfd);
+       ASSERT_EQ(EINVAL, errno);
+}
+
+TEST_F(reset_shmem_enabled, restrictedmem_rmfd_hugepage)
+{
+       int mfd = -1;
+       struct stat stat;
+
+       ASSERT_EQ(0, set_shmem_thp_policy("never"));
+
+       mfd = memfd_restricted(RMFD_HUGEPAGE, NULL);
+       ASSERT_NE(-1, mfd);
+
+       ASSERT_EQ(0, fstat(mfd, &stat));
+
+       ASSERT_EQ(stat.st_blksize, get_hpage_pmd_size());
+
+       close(mfd);
+}
+
 TEST(restrictedmem_tmpfile_no_mount_path)
 {
        int mfd = memfd_restricted(RMFD_TMPFILE, NULL);
-- 
2.39.2.637.g21b0678d19-goog