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From:   Muchun Song <songmuchun@bytedance.com>
To:     will@kernel.org, akpm@linux-foundation.org, david@redhat.com,
        osalvador@suse.de, mike.kravetz@oracle.com, rientjes@google.com,
        mark.rutland@arm.com, catalin.marinas@arm.com, james.morse@arm.com,
        21cnbao@gmail.com
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, duanxiongchun@bytedance.com,
        fam.zheng@bytedance.com, smuchun@gmail.com,
        Muchun Song <songmuchun@bytedance.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>
Subject: [PATCH] arm64: mm: hugetlb: restructure the code comment inside flush_dcache_page()
Date:   Thu, 14 Apr 2022 15:26:46 +0800
Message-Id: <20220414072646.21910-1-songmuchun@bytedance.com>
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Restructure the code comment inside flush_dcache_page() to make it more
clear.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---

This is based on next-20220407.

Hi Andrew,

Would you mind help me squash this patch into "arm64: mm: hugetlb: Enable
HUGETLB_PAGE_FREE_VMEMMAP for arm64"?  Because there is some conflicts
with the patchset of hugetlb_vmemmap releated cleanup when you merge
if I resend the original patch.

 arch/arm64/mm/flush.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index 9e39598bbc21..fc4f710e9820 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -81,9 +81,10 @@ void flush_dcache_page(struct page *page)
 	 * read-only when CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is enabled (more
 	 * details can refer to vmemmap_remap_pte()).  Although
 	 * __sync_icache_dcache() only set PG_dcache_clean flag on the head
-	 * page struct, some tail page structs still can be seen the flag is
-	 * set since the head vmemmap page frame is reused (more details can
-	 * refer to the comments above page_fixed_fake_head()).
+	 * page struct, there is more than one page struct with PG_dcache_clean
+	 * associated with the HugeTLB page since the head vmemmap page frame
+	 * is reused (more details can refer to the comments above
+	 * page_fixed_fake_head()).
 	 */
 	if (hugetlb_optimize_vmemmap_enabled() && PageHuge(page))
 		page = compound_head(page);
-- 
2.11.0