mm/page_vma_mapped.c: check possible huge PMD map with transhuge_vma_suitable()
IIUC page_vma_mapped_walk() checks if the vma is possibly huge PMD mapped with transparent_hugepage_active() and "pvmw->nr_pages >= HPAGE_PMD_NR". Actually pvmw->nr_pages is returned by compound_nr() or folio_nr_pages(), so the page should be THP as long as "pvmw->nr_pages >= HPAGE_PMD_NR". And it is guaranteed THP is allocated for valid VMA in the first place. But it may be not PMD mapped if the VMA is file VMA and it is not properly aligned. The transhuge_vma_suitable() is used to do such check, so replace transparent_hugepage_active() to it, which is too heavy and overkilling. Link: https://lkml.kernel.org/r/20220513191705.457775-1-shy828301@gmail.comSigned-off-by:Yang Shi <shy828301@gmail.com> Reviewed-by:
Muchun Song <songmuchun@bytedance.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org>
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