From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 022ADC3F2C6 for ; Fri, 28 Feb 2020 01:21:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D51272468A for ; Fri, 28 Feb 2020 01:21:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730740AbgB1BVp (ORCPT ); Thu, 27 Feb 2020 20:21:45 -0500 Received: from shelob.surriel.com ([96.67.55.147]:46704 "EHLO shelob.surriel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730463AbgB1BVp (ORCPT ); Thu, 27 Feb 2020 20:21:45 -0500 Received: from imladris.surriel.com ([96.67.55.152]) by shelob.surriel.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.3) (envelope-from ) id 1j7ULS-0002E6-U5; Thu, 27 Feb 2020 20:21:38 -0500 Message-ID: <7800e98e3688c124ac3672284b87d67321e1c29e.camel@surriel.com> Subject: Re: [PATCH v2 2/2] mm,thp,compaction,cma: allow THP migration for CMA allocations From: Rik van Riel To: Mike Kravetz , linux-kernel@vger.kernel.org Cc: kernel-team@fb.com, akpm@linux-foundation.org, linux-mm@kvack.org, mhocko@kernel.org, vbabka@suse.cz, mgorman@techsingularity.net, rientjes@google.com, aarcange@redhat.com, ziy@nvidia.com Date: Thu, 27 Feb 2020 20:21:38 -0500 In-Reply-To: References: <20200227213238.1298752-2-riel@surriel.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-GuN/ZXBkrY1Ye2qQ9BQv" User-Agent: Evolution 3.34.3 (3.34.3-1.fc31) MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-GuN/ZXBkrY1Ye2qQ9BQv Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 2020-02-27 at 15:41 -0800, Mike Kravetz wrote: > On 2/27/20 1:32 PM, Rik van Riel wrote: > >=20 > > +++ b/mm/page_alloc.c > > @@ -8253,14 +8253,19 @@ struct page *has_unmovable_pages(struct > > zone *zone, struct page *page, > > =20 > > /* > > * Hugepages are not in LRU lists, but they're movable. > > + * THPs are on the LRU, but need to be counted as > > #small pages. > > * We need not scan over tail pages because we don't > > * handle each tail page individually in migration. > > */ > > - if (PageHuge(page)) { > > + if (PageHuge(page) || PageTransCompound(page)) { > > struct page *head =3D compound_head(page); > > unsigned int skip_pages; > > =20 > > - if > > (!hugepage_migration_supported(page_hstate(head))) > > + if (PageHuge(page) && > > + !hugepage_migration_supported(page_hstate(h > > ead))) > > + return page; > > + > > + if (!PageLRU(head) && !__PageMovable(head)) >=20 > Pretty sure this is going to be true for hugetlb pages. So, this > will change > behavior and make all hugetlb pages look unmovable. Perhaps, only > check this > condition for THP pages? Does that need to be the following, then? if (PageTransHuge(head) && !PageHuge(page) && !PageLRU(head) && !__PageMovable(head)) return page; That's an easy one liner I would be happy to send in if everybody agrees that should fix things :) --=20 All Rights Reversed. --=-GuN/ZXBkrY1Ye2qQ9BQv Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEKR73pCCtJ5Xj3yADznnekoTE3oMFAl5YayIACgkQznnekoTE 3oPx0Af/TX+zEkUxcEv+yrrOG4Jv1BzQ8b6pdaygAYaEH2MhPrSDgprArigLLmWl 2eWVDfgfoNPn1FW1//hUCZREJvTFQDd5UgtrXiCVw3qXt66mI0OfQQ6FtSh9yWM1 YV2D7uzDucuGYd16wFVeOs5XkVtNZk1o1TjCWBi1UVMScPU42HROoG3rrZ3kPEtG JuXCdAPOq3S3s+PwyBushTVe51LNZCSFjA1lv0Y5viT52TgZU+ugySCme7wOnpb1 mT5UMkrUyjhye2TAqr0h3z8gpTYOG7uX5psZRx77l6eG89IedY/0hOAyk0MgwtSz iqGb8+FoH3rjeRiXsrQ9JHpc/uW3ug== =zMII -----END PGP SIGNATURE----- --=-GuN/ZXBkrY1Ye2qQ9BQv--