[PATCH 40/53] selftests/mm: hugetlb-shm: add setup of HugeTLB pages

[Mike Rapoport]

From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx>

hugetlb-shm test fails if there are no free huge pages prepared by a
wrapper script and shm liimts in proc are too low.

Add setup of HugeTLB pages and shm limits to the test and make sure that
the original settings are restored on the test exit.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
---
 tools/testing/selftests/mm/hugetlb-shm.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/tools/testing/selftests/mm/hugetlb-shm.c b/tools/testing/selftests/mm/hugetlb-shm.c
index 10e4baa091f2..e721ef17974c 100644
--- a/tools/testing/selftests/mm/hugetlb-shm.c
+++ b/tools/testing/selftests/mm/hugetlb-shm.c
@@ -29,9 +29,24 @@
 #include <sys/mman.h>
 
 #include "vm_util.h"
+#include "hugepage_settings.h"
 
 #define LENGTH (256UL*1024*1024)
 
+static void prepare(void)
+{
+	unsigned long length, hugepage_size, nr;
+
+	hugepage_size = default_huge_page_size();
+	length = (LENGTH + hugepage_size) & ~(hugepage_size - 1);
+	nr = length / hugepage_size;
+
+	if (!hugetlb_setup_default(nr))
+		ksft_exit_skip("Not enough free huge pages\n");
+
+	shm_limits_prepare(length);
+}
+
 int main(void)
 {
 	int shmid;
@@ -41,6 +56,8 @@ int main(void)
 	ksft_print_header();
 	ksft_set_plan(1);
 
+	prepare();
+
 	shmid = shmget(2, LENGTH, SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
 	if (shmid < 0)
 		ksft_exit_fail_perror("shmget");
@@ -79,3 +96,5 @@ int main(void)
 	ksft_test_result_pass("hugepage using SysV shmget/shmat\n");
 	ksft_finished();
 }
+
+SHM_LIMITS_RESTORE()
-- 
2.53.0