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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 071B9C6379D for ; Mon, 23 Nov 2020 08:05:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E92F204EF for ; Mon, 23 Nov 2020 08:05:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ZAqo9NfK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728188AbgKWIFQ (ORCPT ); Mon, 23 Nov 2020 03:05:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725998AbgKWIFQ (ORCPT ); Mon, 23 Nov 2020 03:05:16 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5584CC0613CF; Mon, 23 Nov 2020 00:05:16 -0800 (PST) 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=6vGNH6/LtgD9H2B7jY2SC28nVQh3dS5TfEwthu4Yqq0=; b=ZAqo9NfKjGkL2SJi0Et2eFTHHn SyVCEbdUmUIfwpdvBuuWvFBs+XXOd7k1xLJehh+E7u1OeHRW7tdsHvERCOFJ18rpuaDwZrh2Bpf4p GHifpGgC0MOM2Cj739hSkfHtJxZ7U412O1Tzn65r8/mLOHMADt9YJdfREPFf2EtryGT+OIY+r4Nz1 WBeADPY66kCsCM8yUaREC77lOZ09vI2AT1QsaaFr1N1hHvNXhVevUpoQ2ZnJ531G4XlESqBTwNfAN 9Se0TiLHstfosyW2NcAEDqbCjU1U+jZvKjRy4hDToRxwrdt597/uGrDfWAgjbGxLFhVXqyo8FblrG HduUcWMw==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kh6qQ-000852-Hy; Mon, 23 Nov 2020 08:05:06 +0000 Date: Mon, 23 Nov 2020 08:05:06 +0000 From: Christoph Hellwig To: David Howells Cc: Pavel Begunkov , Matthew Wilcox , Jens Axboe , Alexander Viro , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 01/29] iov_iter: Switch to using a table of operations Message-ID: <20201123080506.GA30578@infradead.org> References: <160596800145.154728.7192318545120181269.stgit@warthog.procyon.org.uk> <160596801020.154728.15935034745159191564.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <160596801020.154728.15935034745159191564.stgit@warthog.procyon.org.uk> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Sat, Nov 21, 2020 at 02:13:30PM +0000, David Howells wrote: > Switch to using a table of operations. In a future patch the individual > methods will be split up by type. For the moment, however, the ops tables > just jump directly to the old functions - which are now static. Inline > wrappers are provided to jump through the hooks. > > Signed-off-by: David Howells Please run performance tests. I think the indirect calls could totally wreck things like high performance direct I/O, especially using io_uring on x86.