[PATCH 4/5] selftests/mm: Configure nr_hugepages for arm64

[Chaitanya S Prakash]

Arm64 has a default hugepage size of 512MB when CONFIG_ARM64_64K_PAGES=y
is enabled. While testing on arm64 platforms having up to 4PB of virtual
address space, a minimum of 6 hugepages were required for all test cases
to pass. Support for this requirement has been added.

Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx 
Signed-off-by: Chaitanya S Prakash <chaitanyas.prakash@xxxxxxx>
---
 tools/testing/selftests/mm/run_vmtests.sh | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh
index eb9823a6959a..7616b3e4a0f0 100644
--- a/tools/testing/selftests/mm/run_vmtests.sh
+++ b/tools/testing/selftests/mm/run_vmtests.sh
@@ -222,8 +222,16 @@ CATEGORY="hugetlb" run_test ./thuge-gen
 if [ $VADDR64 -ne 0 ]; then
 	CATEGORY="hugevm" run_test ./virtual_address_range
 
-	# virtual address 128TB switch test
+	# va high address boundary switch test
+	ARCH_ARM64="arm64"
+	prev_nr_hugepages=$(cat /proc/sys/vm/nr_hugepages)
+	if [ "$ARCH" == "$ARCH_ARM64" ]; then
+		echo 6 > /proc/sys/vm/nr_hugepages
+	fi
 	CATEGORY="hugevm" run_test ./va_high_addr_switch.sh
+	if [ "$ARCH" == "$ARCH_ARM64" ]; then
+		echo $prev_nr_hugepages > /proc/sys/vm/nr_hugepages
+	fi
 fi # VADDR64
 
 # vmalloc stability smoke test
-- 
2.30.2