!1796 arm64: enable THP_SWAP for arm64

Merge Pull Request from: @ci-robot 
 
PR sync from: Jinjiang Tu <tujinjiang@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/SSNB2TJLFOGTWITPC5QTJ4DGB4WFMNJF/ 
 
https://gitee.com/openeuler/kernel/issues/I7TVRF 
 
Link:https://gitee.com/openeuler/kernel/pulls/1796 

Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> 
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com> 

arch/arm64/Kconfig

@@ -86,6 +86,7 @@ config ARM64
 	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
 	select ARCH_WANT_LD_ORPHAN_WARN
 	select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
+	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
 	select ARM_AMBA
 	select ARM_ARCH_TIMER

arch/arm64/include/asm/pgtable.h

@@ -46,6 +46,12 @@
 	__flush_tlb_range(vma, addr, end, PUD_SIZE, false, 1)
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
+static inline bool arch_thp_swp_supported(void)
+{
+	return !system_supports_mte();
+}
+#define arch_thp_swp_supported arch_thp_swp_supported
+
 /*
  * Outside of a few very special situations (e.g. hibernation), we always
  * use broadcast TLB invalidation instructions, therefore a spurious page

include/linux/huge_mm.h

@@ -499,4 +499,16 @@ static inline unsigned long thp_size(struct page *page)
 	return PAGE_SIZE << thp_order(page);
 }
 
+/*
+ * archs that select ARCH_WANTS_THP_SWAP but don't support THP_SWP due to
+ * limitations in the implementation like arm64 MTE can override this to
+ * false
+ */
+#ifndef arch_thp_swp_supported
+static inline bool arch_thp_swp_supported(void)
+{
+	return true;
+}
+#endif
+
 #endif /* _LINUX_HUGE_MM_H */

mm/swap_slots.c

@@ -436,7 +436,7 @@ swp_entry_t get_swap_page(struct page *page)
 		goto out;
 
 	if (PageTransHuge(page)) {
-		if (IS_ENABLED(CONFIG_THP_SWAP))
+		if (IS_ENABLED(CONFIG_THP_SWAP) && arch_thp_swp_supported())
 			get_swap_pages(1, &entry, HPAGE_PMD_NR, type);
 		goto out;
 	}