From 461a7184320a1b4d2c12ad538354062fef4ee0f1 Mon Sep 17 00:00:00 2001
From: Yisheng Xie <xieyisheng1@huawei.com>
Date: Fri, 7 Oct 2016 17:01:46 -0700
Subject: [PATCH] mm/hugetlb: introduce ARCH_HAS_GIGANTIC_PAGE

Avoid making ifdef get pretty unwieldy if many ARCHs support gigantic
page.  No functional change with this patch.

Link: http://lkml.kernel.org/r/1475227569-63446-2-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/s390/Kconfig | 1 +
 arch/x86/Kconfig  | 1 +
 fs/Kconfig        | 3 +++
 mm/hugetlb.c      | 2 +-
 4 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index deeadfa291ba..fb538031569a 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -71,6 +71,7 @@ config S390
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_GCOV_PROFILE_ALL
+	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_SG_CHAIN
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 58bec8f9641a..827273c56ae9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -28,6 +28,7 @@ config X86
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_GCOV_PROFILE_ALL
+	select ARCH_HAS_GIGANTIC_PAGE		if X86_64
 	select ARCH_HAS_KCOV			if X86_64
 	select ARCH_HAS_PMEM_API		if X86_64
 	select ARCH_HAS_MMIO_FLUSH
diff --git a/fs/Kconfig b/fs/Kconfig
index 3ef62bad8f2b..4bd03a2b0518 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -200,6 +200,9 @@ config HUGETLBFS
 config HUGETLB_PAGE
 	def_bool HUGETLBFS
 
+config ARCH_HAS_GIGANTIC_PAGE
+	bool
+
 source "fs/configfs/Kconfig"
 source "fs/efivarfs/Kconfig"
 
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 770d83eb3f48..e4a4500758f2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1022,7 +1022,7 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
 		((node = hstate_next_node_to_free(hs, mask)) || 1);	\
 		nr_nodes--)
 
-#if (defined(CONFIG_X86_64) || defined(CONFIG_S390)) && \
+#if defined(CONFIG_ARCH_HAS_GIGANTIC_PAGE) && \
 	((defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || \
 	defined(CONFIG_CMA))
 static void destroy_compound_gigantic_page(struct page *page,
-- 
2.20.1