Message ID | 20200318140253.6141-5-willy@infradead.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Misc MM patches | expand |
On Wed, Mar 18, 2020 at 07:02:49AM -0700, Matthew Wilcox wrote: > From: "Matthew Wilcox (Oracle)" <willy@infradead.org> > > If THP is disabled, find_subpage() can become a no-op by using > hpage_nr_pages() instead of compound_nr(). hpage_nr_pages() embeds > a check for PageTail, so we can drop the check here. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Looks good, Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 68db0ed8535d..fcb4887e65e8 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -343,9 +343,7 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index) if (PageHuge(head)) return head; - VM_BUG_ON_PAGE(PageTail(head), head); - - return head + (index & (compound_nr(head) - 1)); + return head + (index & (hpage_nr_pages(head) - 1)); } struct page *find_get_entry(struct address_space *mapping, pgoff_t offset);