On Thu, Feb 01, 2024 at 02:52:31PM +0100, Jan Kara wrote: > On Thu 01-02-24 13:47:03, Matthew Wilcox wrote: > > On Thu, Feb 01, 2024 at 06:08:34PM +0800, Liu Shixin wrote: > > > @@ -247,9 +248,12 @@ void page_cache_ra_unbounded(struct readahead_control *ractl, > > > folio = filemap_alloc_folio(gfp_mask, 0); > > > if (!folio) > > > break; > > > - if (filemap_add_folio(mapping, folio, index + i, > > > - gfp_mask) < 0) { > > > + > > > + ret = filemap_add_folio(mapping, folio, index + i, gfp_mask); > > > + if (ret < 0) { > > > folio_put(folio); > > > + if (ret == -ENOMEM) > > > + break; > > > > No, that's too early. You've still got a batch of pages which were > > successfully added; you have to read them. You were only off by one > > line though ;-) > > There's a read_pages() call just outside of the loop so this break is > actually fine AFAICT. Oh, good point! I withdraw my criticism.