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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 ACA2FC2D0A8 for ; Mon, 28 Sep 2020 19:34:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E14142074A for ; Mon, 28 Sep 2020 19:34:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Cv+Rj1qL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E14142074A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 64F988E0001; Mon, 28 Sep 2020 15:34:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5FECE6B0070; Mon, 28 Sep 2020 15:34:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4C5E48E0001; Mon, 28 Sep 2020 15:34:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0246.hostedemail.com [216.40.44.246]) by kanga.kvack.org (Postfix) with ESMTP id 32D806B006E for ; Mon, 28 Sep 2020 15:34:35 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DFE18180AD802 for ; Mon, 28 Sep 2020 19:34:34 +0000 (UTC) X-FDA: 77313472068.14.rat01_5717b8427184 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id BB78118229818 for ; Mon, 28 Sep 2020 19:34:34 +0000 (UTC) X-HE-Tag: rat01_5717b8427184 X-Filterd-Recvd-Size: 2710 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf34.hostedemail.com (Postfix) with ESMTP for ; Mon, 28 Sep 2020 19:34:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=SVVt673+CBkGesVVi65p5GK+Sq59pADfZtIFLQRkELk=; b=Cv+Rj1qLsnkTaY0gvf9+w2C0zN cVDHFG5u7qrRWH09Cp32Tq9UcKn7U83LtfNGDSF006MUjyfYS0wzwBUvcdlVWLfcTvsAfM30B2MFR ijmE+RRx3Wju2QhRkK+9B429YGjbBAVQuoD82U+3hk1fZjcdEqmuiP/TPjimSmtwQEcb9x6l1XTWH 7mVw5wvXVOtAVF21Lc0mizlOrUJklkjZnqiuXUAPS9OzbaZsUrCRi7m9SwrHpnRrzcFqryytiTHo+ KOTq8n0rf52XtvufFETht3VnUQiwUUCxXyoezKKdKddc9/Gukgjkpvfomi7rogne901Gp0JBWKiGX 9ct8p21g==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kMyuq-0007rD-RF; Mon, 28 Sep 2020 19:34:29 +0000 Date: Mon, 28 Sep 2020 20:34:28 +0100 From: Matthew Wilcox To: Zi Yan Cc: linux-mm@kvack.org, "Kirill A . Shutemov" , Roman Gushchin , Rik van Riel , Shakeel Butt , Yang Shi , Jason Gunthorpe , Mike Kravetz , Michal Hocko , David Hildenbrand , William Kucharski , Andrea Arcangeli , John Hubbard , David Nellans , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 03/30] mm: thp: use single linked list for THP page table page deposit. Message-ID: <20200928193428.GB30994@casper.infradead.org> References: <20200928175428.4110504-1-zi.yan@sent.com> <20200928175428.4110504-4-zi.yan@sent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200928175428.4110504-4-zi.yan@sent.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Sep 28, 2020 at 01:54:01PM -0400, Zi Yan wrote: > struct { /* Page table pages */ > - unsigned long _pt_pad_1; /* compound_head */ > - pgtable_t pmd_huge_pte; /* protected by page->ptl */ > + struct llist_head deposit_head; /* pgtable deposit list head */ > + struct llist_node deposit_node; /* pgtable deposit list node */ If you're going to use two pointers anyway, you might as well use a list_head. But I don't think you need to; you could either use a union of these or you could use the page_address() of the page to store as much information as you like!