ARM: 9328/1: mm: try VMA lock-based page fault handling first

[ Upstream commit c16af121

 ]

Attempt VMA lock-based page fault handling first, and fall back to the
existing mmap_lock-based handling if that fails, the ebizzy benchmark
shows 25% improvement on qemu with 2 cpus.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Stable-dep-of: e870920b

 ("arch/arm/mm: fix major fault accounting when retrying under per-VMA lock")
Signed-off-by: Sasha Levin <sashal@kernel.org>