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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 10E7AC43331 for ; Wed, 1 Apr 2020 15:25:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D7D89208FE for ; Wed, 1 Apr 2020 15:25:28 +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="QIe0p59L" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732756AbgDAPZ2 (ORCPT ); Wed, 1 Apr 2020 11:25:28 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:33774 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732504AbgDAPZ2 (ORCPT ); Wed, 1 Apr 2020 11:25:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:In-Reply-To:References; bh=4BS8ivTCYFspki1TbBqRnlzcyvC7A7pG5kcAWU25CRM=; b=QIe0p59LYWgpBVUCjU4DFDQkod XtoWdCHWIOL8HHvfCQ+03y9wErs5qHWwK7NyQcmccuUl7dxJMzgUvYpA3PZ3f5IRBpMjNfySksqI4 MP9ctDsrZ6yy1ouKzoIUtQvBdfoWmEdI9qiuGL5rlg50Ba7TFiesoRxBXwOnFJmvYOwyuyVotKGSu sv/yBEAsISEax8IZq3d7e+u0zGVmCc7MLEYZb5Kgmt1aXAy8T3ENFoEyrx1+PZ42QPyqwMQprJBP5 sbaECNcA8h6GsKgWDqHevbwSDiW39VPjoA9kOOK1UHa8CRJ9zWsqsDWJPRI2NbcgANXiRjRlvQxAN IuBtTvtg==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jJfF9-0005Pa-Tq; Wed, 01 Apr 2020 15:25:27 +0000 From: Matthew Wilcox To: hch@infradead.org Cc: "Matthew Wilcox (Oracle)" , linux-xfs@vger.kernel.org Subject: [RFC 0/2] Begin switching iomap from apply to iter Date: Wed, 1 Apr 2020 08:25:20 -0700 Message-Id: <20200401152522.20737-1-willy@infradead.org> X-Mailer: git-send-email 2.21.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: "Matthew Wilcox (Oracle)" I don't like the 'apply' design pattern. It splits the logic between two functions, and from a performance point of view, it introduces an indirect function call which is more expensive due to Spectre. This rfc only converts one function over to use the new API as a demonstration. I don't want to waste time on it if people aren't interested in this approach. I haven't tested this at all; it's probably buggy. Matthew Wilcox (Oracle) (2): iomap: Add iomap_iter API iomap: Convert page_mkwrite to iter API fs/iomap/Makefile | 2 +- fs/iomap/buffered-io.c | 51 ++++++++++---------------- fs/iomap/iter.c | 81 ++++++++++++++++++++++++++++++++++++++++++ include/linux/iomap.h | 24 +++++++++++++ 4 files changed, 125 insertions(+), 33 deletions(-) create mode 100644 fs/iomap/iter.c -- 2.25.1