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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 CC560C388F4 for ; Mon, 30 Sep 2019 08:06:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A0EBC2075D for ; Mon, 30 Sep 2019 08:06:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728310AbfI3IGW (ORCPT ); Mon, 30 Sep 2019 04:06:22 -0400 Received: from verein.lst.de ([213.95.11.211]:35237 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725767AbfI3IGW (ORCPT ); Mon, 30 Sep 2019 04:06:22 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 107A768AFE; Mon, 30 Sep 2019 10:06:14 +0200 (CEST) Date: Mon, 30 Sep 2019 10:06:13 +0200 From: Christoph Hellwig To: Vlastimil Babka Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter , Pekka Enberg , David Rientjes , Ming Lei , Dave Chinner , Matthew Wilcox , "Darrick J . Wong" , Christoph Hellwig , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, James Bottomley , linux-btrfs@vger.kernel.org, Roman Gushchin , Johannes Weiner Subject: Re: [PATCH v2 2/2] mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two) Message-ID: <20190930080613.GA5379@lst.de> References: <20190826111627.7505-1-vbabka@suse.cz> <20190826111627.7505-3-vbabka@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Mon, Sep 23, 2019 at 06:36:32PM +0200, Vlastimil Babka wrote: > So if anyone thinks this is a good idea, please express it (preferably > in a formal way such as Acked-by), otherwise it seems the patch will be > dropped (due to a private NACK, apparently). I think we absolutely need something like this, and I'm sick and tired of the people just claiming there is no problem. >From the user POV I don't care if aligned allocations need a new GFP_ALIGNED flag or not, but as far as I can tell the latter will probably cause more overhead in practice than not having it. So unless someone comes up with a better counter proposal to provide aligned kmalloc of some form that doesn't require a giant amount of boilerplate code in the users: Acked^2-by: Christoph Hellwig