selftests/mm: add shmem-private test to uffd-stress

The userfaultfd stress test never tested private shmem, which I think was
overlooked long due.  Add it so it matches with uffd unit test and it'll
cover all memory supported with the three memory types.

Meanwhile, rename the memory types a bit.  Considering shared mem is the
major use case for both shmem / hugetlbfs, changing from:

  anon, hugetlb, hugetlb_shared, shmem

To (with shmem-private added):

  anon, hugetlb, hugetlb-private, shmem, shmem-private

Add the shmem-private to run_vmtests.sh too.

Link: https://lkml.kernel.org/r/20230412164546.329355-1-peterx@redhat.comSigned-off-by: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

tools/testing/selftests/mm/run_vmtests.sh

@@ -202,8 +202,9 @@ CATEGORY="userfaultfd" run_test ${uffd_stress_bin} anon 20 16
 # Hugetlb tests require source and destination huge pages. Pass in half
 # the size ($half_ufd_size_MB), which is used for *each*.
 CATEGORY="userfaultfd" run_test ${uffd_stress_bin} hugetlb "$half_ufd_size_MB" 32
-CATEGORY="userfaultfd" run_test ${uffd_stress_bin} hugetlb_shared "$half_ufd_size_MB" 32
+CATEGORY="userfaultfd" run_test ${uffd_stress_bin} hugetlb-private "$half_ufd_size_MB" 32
 CATEGORY="userfaultfd" run_test ${uffd_stress_bin} shmem 20 16
+CATEGORY="userfaultfd" run_test ${uffd_stress_bin} shmem-private 20 16
 
 #cleanup
 echo "$nr_hugepgs" > /proc/sys/vm/nr_hugepages

tools/testing/selftests/mm/uffd-stress.c

@@ -59,8 +59,8 @@ const char *examples =
     "./userfaultfd shmem 1000 99\n\n"
     "# Run hugetlb memory test on 256MiB region with 50 bounces:\n"
     "./userfaultfd hugetlb 256 50\n\n"
-    "# Run the same hugetlb test but using shared file:\n"
-    "./userfaultfd hugetlb_shared 256 50\n\n"
+    "# Run the same hugetlb test but using private file:\n"
+    "./userfaultfd hugetlb-private 256 50\n\n"
     "# 10MiB-~6GiB 999 bounces anonymous test, "
     "continue forever unless an error triggers\n"
     "while ./userfaultfd anon $[RANDOM % 6000 + 10] 999; do true; done\n\n";
@@ -69,7 +69,7 @@ static void usage(void)
 {
 	fprintf(stderr, "\nUsage: ./userfaultfd <test type> <MiB> <bounces>\n\n");
 	fprintf(stderr, "Supported <test type>: anon, hugetlb, "
-		"hugetlb_shared, shmem\n\n");
+		"hugetlb-private, shmem, shmem-private\n\n");
 	fprintf(stderr, "Examples:\n\n");
 	fprintf(stderr, "%s", examples);
 	exit(1);
@@ -376,14 +376,17 @@ static void set_test_type(const char *type)
 	} else if (!strcmp(type, "hugetlb")) {
 		test_type = TEST_HUGETLB;
 		uffd_test_ops = &hugetlb_uffd_test_ops;
-	} else if (!strcmp(type, "hugetlb_shared")) {
 		map_shared = true;
+	} else if (!strcmp(type, "hugetlb-private")) {
 		test_type = TEST_HUGETLB;
 		uffd_test_ops = &hugetlb_uffd_test_ops;
 	} else if (!strcmp(type, "shmem")) {
 		map_shared = true;
 		test_type = TEST_SHMEM;
 		uffd_test_ops = &shmem_uffd_test_ops;
+	} else if (!strcmp(type, "shmem-private")) {
+		test_type = TEST_SHMEM;
+		uffd_test_ops = &shmem_uffd_test_ops;
 	}
 }