folio_mapped() is expensive because it has to check each page's mapcount field. A cheaper check is whether there are any extra references to the page, other than the one we own and the ones held by the page cache. The call to remove_mapping() will fail in any case if it cannot freeze the refcount, but failing here avoids cycling the i_pages spinlock. Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> --- mm/truncate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/truncate.c b/mm/truncate.c index b73c30c95cd0..d67fa8871b75 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -287,7 +287,7 @@ int invalidate_inode_page(struct page *page) return 0; if (folio_test_dirty(folio) || folio_test_writeback(folio)) return 0; - if (page_mapped(page)) + if (folio_ref_count(folio) > folio_nr_pages(folio) + 1) return 0; if (folio_has_private(folio) && !filemap_release_folio(folio, 0)) return 0; -- 2.34.1