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From:   Zi Yan <zi.yan@sent.com>
To:     linux-mm@kvack.org, Roman Gushchin <guro@fb.com>
Cc:     Rik van Riel <riel@surriel.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Matthew Wilcox <willy@infradead.org>,
        Shakeel Butt <shakeelb@google.com>,
        Yang Shi <yang.shi@linux.alibaba.com>,
        David Nellans <dnellans@nvidia.com>,
        linux-kernel@vger.kernel.org, Zi Yan <ziy@nvidia.com>
Subject: [RFC PATCH 03/16] mm: proc: add 1GB THP kpageflag.
Date:   Wed,  2 Sep 2020 14:06:15 -0400
Message-Id: <20200902180628.4052244-4-zi.yan@sent.com>
In-Reply-To: <20200902180628.4052244-1-zi.yan@sent.com>
References: <20200902180628.4052244-1-zi.yan@sent.com>
Reply-To: Zi Yan <ziy@nvidia.com>
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From: Zi Yan <ziy@nvidia.com>

Bit 27 is used to identify 1GB THP.

Signed-off-by: Zi Yan <ziy@nvidia.com>
---
 fs/proc/page.c                         | 2 ++
 include/uapi/linux/kernel-page-flags.h | 2 ++
 2 files changed, 4 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..cdeb33ab655c 100644
--- a/include/uapi/linux/kernel-page-flags.h
+++ b/include/uapi/linux/kernel-page-flags.h
@@ -36,5 +36,7 @@
 #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