[PATCH v4 42/55] selftests/mm: hugetlb-shm: add setup of HugeTLB pages

[Mike Rapoport <rppt@kernel.org>]

From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>

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.

Tested-by: Luiz Capitulino <luizcap@redhat.com>
Tested-by: Sarthak Sharma <sarthak.sharma@arm.com>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
 tools/testing/selftests/mm/hugetlb-shm.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tools/testing/selftests/mm/hugetlb-shm.c b/tools/testing/selftests/mm/hugetlb-shm.c
index c2c7aee85b96..3ff7f062b7eb 100644
--- a/tools/testing/selftests/mm/hugetlb-shm.c
+++ b/tools/testing/selftests/mm/hugetlb-shm.c
@@ -29,9 +29,27 @@
 #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();
+	if (!hugepage_size)
+		ksft_exit_skip("Unable to determine huge page size\n");
+
+	length = (LENGTH + hugepage_size - 1) & ~(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 +59,8 @@ 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");
@@ -76,3 +96,5 @@ int main(void)
 	ksft_test_result_pass("hugepage using SysV shmget/shmat\n");
 	ksft_finished();
 }
+
+SHM_LIMITS_RESTORE()
-- 
2.53.0