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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31C63ECAAD3 for ; Mon, 5 Sep 2022 15:26:00 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 476A8801EE; Mon, 5 Sep 2022 11:25:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3FF16801E6; Mon, 5 Sep 2022 11:25:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 29F26801EE; Mon, 5 Sep 2022 11:25:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 17AED801E6 for ; Mon, 5 Sep 2022 11:25:59 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id E6DDFA0EA4 for ; Mon, 5 Sep 2022 15:25:58 +0000 (UTC) X-FDA: 79878407196.25.7C91C27 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf11.hostedemail.com (Postfix) with ESMTP id 459964005B for ; Mon, 5 Sep 2022 15:25:58 +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=uplnyYpk3INJufSvSlwxeNSTQlXrZkSXonYNwz6iYNM=; b=qNiIUbe9pcC2Mgcn0CDsgRJGJe MfJpPV+a7WqyQuY141JBCJ+S9C8TipGUk5/rFJXiVaoMHUv9276itWCyIuNcUwqIuDQ7cFvERRGiI uuscuHbk1bKFTLF7x3X7DKhlDno6T0Vv4XFXK2IfAaely1IqoZocr+lLK5VZ95ugzKZQBZBSRXAKz zDKFckrcQg9mAqlWZeiegQupTgdCsfguFYlKWIXOy+l+M7gFaLkBYAxy2YLzfSNPcQjt+NHR8bTP6 w90QXIbM2SXgHp+ZerIUpawE/BXHs6BnV/kSwfk19kb3E99ICMcQjbeyenpszf6+Xhzv54cOs7k0T F5y9Q1tA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1oVDyr-009at3-47; Mon, 05 Sep 2022 15:25:45 +0000 Date: Mon, 5 Sep 2022 16:25:45 +0100 From: Matthew Wilcox To: Cheng Li Cc: mike.kravetz@oracle.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm: use mem_map_offset instead of mem_map_next Message-ID: References: <1662358159-22780-1-git-send-email-lic121@chinatelecom.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1662358159-22780-1-git-send-email-lic121@chinatelecom.cn> ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1662391558; a=rsa-sha256; cv=none; b=Mxx7KA7ImzpBFBOoT5G4FmrtqWT9EblUarrQ+KOanttxTaBkvFMn06A/uwIDrcPL6NAwg4 g8i2OQ4gFC/My4p6zzUrF7v39ETBbM7gRcDwBgVox66tQavepH5IVla4lLmHwI2z3z5u0l JXt4xpMaTuSOrcia1KVnokDoUAccyjs= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=qNiIUbe9; spf=none (imf11.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1662391558; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=uplnyYpk3INJufSvSlwxeNSTQlXrZkSXonYNwz6iYNM=; b=D/XbMMER4NwiT6KiUFuBwBIFfr3823W+5YlIJBrO9IDoB1qIgECIA08q2KvHp7SYxqdM74 7LfXZf1E7xj5lIqj38YfneANavtgRB6xkUFZwBrCrwWm6fu/trQqCAIlyaDKuRhKRnrC06 YCs2+yjg2xP/WAa9xmcAjlyUf7nDdBM= X-Stat-Signature: idjckz71eeurts4swwfnqxkpbbkad569 X-Rspamd-Queue-Id: 459964005B Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=qNiIUbe9; spf=none (imf11.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1662391558-298702 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 05, 2022 at 06:09:19AM +0000, Cheng Li wrote: > To handle discontiguity case, mem_map_next() has a parameter named > `offset`. As a function caller, one would be confused why "get > next entry" needs a parameter named "offset". The other drawback of > mem_map_next() is that the callers must take care of the map between > parameter "iter" and "offset", otherwise we may get an hole or > duplication during iteration. So we use mem_map_offset instead of > mem_map_next. Per my previous email, use nth_page(), not mem_map_offset().