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_PASS autolearn=ham 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 00326C6778C for ; Wed, 4 Jul 2018 02:25:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8CD2246DE for ; Wed, 4 Jul 2018 02:25:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B8CD2246DE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933138AbeGDCZA (ORCPT ); Tue, 3 Jul 2018 22:25:00 -0400 Received: from mga02.intel.com ([134.134.136.20]:50129 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932853AbeGDCY7 (ORCPT ); Tue, 3 Jul 2018 22:24:59 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Jul 2018 19:24:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,306,1526367600"; d="scan'208";a="68474445" Received: from yhuang-dev.sh.intel.com (HELO yhuang-dev) ([10.239.13.118]) by fmsmga004.fm.intel.com with ESMTP; 03 Jul 2018 19:24:46 -0700 From: "Huang\, Ying" To: Daniel Jordan Cc: Andrew Morton , , , "Kirill A. Shutemov" , Andrea Arcangeli , Michal Hocko , Johannes Weiner , Shaohua Li , Hugh Dickins , Minchan Kim , Rik van Riel , Dave Hansen , Naoya Horiguchi , Zi Yan Subject: Re: [PATCH -mm -v4 08/21] mm, THP, swap: Support to read a huge swap cluster for swapin a THP References: <20180622035151.6676-1-ying.huang@intel.com> <20180622035151.6676-9-ying.huang@intel.com> <20180704001235.w7xexi3jp6ostas5@ca-dmjordan1.us.oracle.com> Date: Wed, 04 Jul 2018 10:24:46 +0800 In-Reply-To: <20180704001235.w7xexi3jp6ostas5@ca-dmjordan1.us.oracle.com> (Daniel Jordan's message of "Tue, 3 Jul 2018 17:12:35 -0700") Message-ID: <874lhfvitt.fsf@yhuang-dev.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Daniel Jordan writes: > On Fri, Jun 22, 2018 at 11:51:38AM +0800, Huang, Ying wrote: >> @@ -411,14 +414,32 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, > ... >> + if (thp_swap_supported() && huge_cluster) { >> + gfp_t gfp = alloc_hugepage_direct_gfpmask(vma); >> + >> + new_page = alloc_hugepage_vma(gfp, vma, >> + addr, HPAGE_PMD_ORDER); > > When allocating a huge page, we ignore the gfp_mask argument. > > That doesn't matter right now since AFAICT we're not losing any flags: gfp_mask > from existing callers of __read_swap_cache_async seems to always be a subset of > GFP_HIGHUSER_MOVABLE and alloc_hugepage_direct_gfpmask always returns a > superset of that. > > But maybe we should warn here in case we end up violating a restriction from a > future caller. Something like this?: > >> + gfp_t gfp = alloc_hugepage_direct_gfpmask(vma); > VM_WARN_ONCE((gfp | gfp_mask) != gfp, > "ignoring gfp_mask bits"); This looks good! Thanks! Will add this. Best Regards, Huang, Ying