On Thu, Jan 26, 2017 at 02:57:55PM +0300, Kirill A. Shutemov wrote: > We writeback whole huge page a time. Let's adjust iteration this way. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> I think a lot of the complexity in this patch is from pagevec_lookup_tag giving you subpages rather than head pages... > @@ -2268,7 +2273,8 @@ int write_cache_pages(struct address_space *mapping, > * not be suitable for data integrity > * writeout). > */ > - done_index = page->index + 1; > + done_index = compound_head(page)->index > + + hpage_nr_pages(page); > done = 1; > break; > } you'd still need this line, but it'd only be: done_index = page->index + (1 << compound_order(page)); I think we want: #define nr_pages(page) (1 << compound_order(page)) because we seem to be repeating that idiom quite a lot in these patches. done_index = page->index + nr_pages(page); Still doesn't quite fit on one line, but it's closer, and it's the ridiculous indentation in that function that's the real problem.
