[RFC PATCH v2 10/30] fs: proc: add PUD THP kpageflag.

[Zi Yan]

From: Zi Yan <ziy@xxxxxxxxxx>

Bit 27 is used to identify PUD THP.

Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
 fs/proc/page.c                         | 2 ++
 include/uapi/linux/kernel-page-flags.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/fs/proc/page.c b/fs/proc/page.c
index f3b39a7d2bf3..e4e2ad3612c9 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -161,6 +161,8 @@ u64 stable_page_flags(struct page *page)
 			u |= BIT_ULL(KPF_ZERO_PAGE);
 			u |= BIT_ULL(KPF_THP);
 		}
+		if (compound_order(head) == HPAGE_PUD_ORDER)
+			u |= 1 << KPF_PUD_THP;
 	} else if (is_zero_pfn(page_to_pfn(page)))
 		u |= BIT_ULL(KPF_ZERO_PAGE);
 
diff --git a/include/uapi/linux/kernel-page-flags.h b/include/uapi/linux/kernel-page-flags.h
index 6f2f2720f3ac..62c5fc70909b 100644
--- a/include/uapi/linux/kernel-page-flags.h
+++ b/include/uapi/linux/kernel-page-flags.h
@@ -36,5 +36,6 @@
 #define KPF_ZERO_PAGE		24
 #define KPF_IDLE		25
 #define KPF_PGTABLE		26
+#define KPF_PUD_THP		27
 
 #endif /* _UAPILINUX_KERNEL_PAGE_FLAGS_H */
-- 
2.28.0