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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 F07DFC04EBC for ; Tue, 20 Nov 2018 13:13:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99D8620685 for ; Tue, 20 Nov 2018 13:12:58 +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="TIWgxvOv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 99D8620685 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 S1726605AbeKTXmB (ORCPT ); Tue, 20 Nov 2018 18:42:01 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:59764 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725902AbeKTXmA (ORCPT ); Tue, 20 Nov 2018 18:42:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Bf5n/hjD4LuBtMg0vL7R93izlrTUbK1wdlLBwdCPRGs=; b=TIWgxvOvFxo9EkS83on2bxDT8 Z6dNHzqjLx23BCOdxrIUqqFghr+G6c40gx4x9Pea0f+A6fS8X9fpHi2Qrc0cmi0e2aL6vBNQHoY+n wzekXfBc9rSrf0rUwssAtHAhoESAWLtWix8IA/Heu+NscKeifEGT7sePZ/xYd0ZSvDfr0S+WZHJ+D tKC+Xz+K9bbHKxDjFPbqRneq94pw19jfPskwDJmAWOn8xDZCwo6Fjse+okwAVAZh3N8MCQsDTvg5z CCE1NvozRB2km34cd+Zev2h0MyIwJMo8eSvBtbILsilFVFpKJdGV4HHSXrbILIMxn2U+nc1YqD3V8 DUbpecEdA==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gP5pf-0003Db-Fr; Tue, 20 Nov 2018 13:12:47 +0000 Date: Tue, 20 Nov 2018 05:12:47 -0800 From: Matthew Wilcox To: Hugh Dickins Cc: Yu Zhao , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm: fix swap offset when replacing shmem page Message-ID: <20181120131247.GA3065@bombadil.infradead.org> References: <20181119004719.156411-1-yuzhao@google.com> <20181119010924.177177-1-yuzhao@google.com> <20181120012950.GA94981@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 19, 2018 at 09:07:27PM -0800, Hugh Dickins wrote: > I don't much like my original use of the name "swap_index", when it was > not the index in a swapfile (though it was the index in the radix tree); > but it will become a correct name with your patch. > > Though Matthew Wilcox seems to want us to avoid saying "radix tree"... Naming is hard ... but the Linux radix tree looks almost nothing like a classic computer science radix tree. If you try to reconcile our implementation with the wikipedia article on radix trees, you'll get very confused. A lot of places where we were saying 'radix tree' in comments should really have said 'page cache'. So is this a swap cache index? I'm not really familiar enough with the swapping code to say.