Let arm64 subscribe to the previously added framework in which architecture
can inform whether a given huge page size is supported for migration. This
just overrides the default function arch_hugetlb_migration_supported() and
enables migration for all possible HugeTLB page sizes on arm64. With this,
HugeTLB migration support on arm64 now covers all possible HugeTLB options.
CONT PTE PMD CONT PMD PUD
-------- --- -------- ---
4K: 64K 2M 32M 1G
16K: 2M 32M 1G
64K: 2M 512M 16G
Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com>
---
arch/arm64/include/asm/hugetlb.h | 5 +++++
arch/arm64/mm/hugetlbpage.c | 20 ++++++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index e73f685..656f70e 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -20,6 +20,11 @@
#include <asm/page.h>
+#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
+#define arch_hugetlb_migration_supported arch_hugetlb_migration_supported
+extern bool arch_hugetlb_migration_supported(struct hstate *h);
+#endif
+
static inline pte_t huge_ptep_get(pte_t *ptep)
{
return READ_ONCE(*ptep);
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 4eafd9f..28f4795 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -27,6 +27,26 @@
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
+#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
+bool arch_hugetlb_migration_supported(struct hstate *h)
+{
+ size_t pagesize = huge_page_size(h);
+
+ switch (pagesize) {
+#ifdef CONFIG_ARM64_4K_PAGES
+ case PUD_SIZE:
+#endif
+ case PMD_SIZE:
+ case CONT_PMD_SIZE:
+ case CONT_PTE_SIZE:
+ return true;
+ }
+ pr_warn("%s: unrecognized huge page size 0x%lx\n",
+ __func__, pagesize);
+ return false;
+}
+#endif
+
int pmd_huge(pmd_t pmd)
{
return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
--
2.7.4
