[PATCH] arm64: mm: hugetlb: restructure the code comment inside flush_dcache_page()

[Muchun Song <songmuchun@bytedance.com>]

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