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=1.5 required=3.0 tests=DKIM_SIGNED,FSL_HELO_FAKE, MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID,USER_AGENT_MUTT 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 9B0FDC43140 for ; Thu, 21 Jun 2018 14:31:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53026208A1 for ; Thu, 21 Jun 2018 14:31:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="B7iz4YyK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 53026208A1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.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 S933178AbeFUObp (ORCPT ); Thu, 21 Jun 2018 10:31:45 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:44454 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932514AbeFUObo (ORCPT ); Thu, 21 Jun 2018 10:31:44 -0400 Received: by mail-wr0-f196.google.com with SMTP id p12-v6so1826090wrn.11 for ; Thu, 21 Jun 2018 07:31:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=QDkqXGQyahGVUCqx9LU0teoulua64IHbcN8YOfTUxVk=; b=B7iz4YyKEJvfkhTSZj0zohu4trSnWet1e5hqxbUA42oCE1WR0BeH91bmSLKWftYvtk bFSmk69EfCmjAELbZ6s7rSpKSXOKJdmQzAPAvVh58UWqFhuwg8FpjFIOwJCdptmp1rtE 9f5et4YifzCa2pWGKoHiUwfJ/DM6vS+hqGyOcrB1jFs/wO9pFFG0FQ671VPvf6FzrGmS xG3mcf32GbRKtmdkojgo5dVmrK8lc83afTQbtGXEkVQfsJ5PN1MxbpQzwUv+EYL9dpeA VbBVc2VKyp/XBlPuAFayxcWV9NKosEeqNI7bhPW77GX78ELM4I+fSMJVE08y8EjbQ4t6 m7JQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=QDkqXGQyahGVUCqx9LU0teoulua64IHbcN8YOfTUxVk=; b=E3MQh+pZc4fHaj8Bc3UDUJ0eI1mULdggmXTfbfWV+0tqP93torXgQw5YQAMEHQKTTA yk5Psz0+CIDrPrmEMvx/ChM17B3WqPXX6J2H7WEUtWvLSWiGtaaGoBZCPxf1+bXGHD4b aCsJrKdw0z2mGnEro1yg6feeUY4CLCGLbSVk8jlE77LBAXMdp3Dbt5on4F0SxthQskZP RBSNfhWfn0WSQW6a6YRkR0tw6qnrlkFagGyNvbF5Pv9PeHFk0TVXi2IMYvGAdnlzTgEy xywqrdo59ejdK2QCUasJxUezmRXRN6gr4MQb/pW1SKUHPcvBuwZusYBTb48YX9yqjUjr ph7w== X-Gm-Message-State: APt69E22LLjY2koZWAsDfI/t0xMV26MHsv88Fns3VA2/YwEwgoHSSayE vtUMRjHdiVOZUq+VL50GdBo= X-Google-Smtp-Source: ADUXVKJGxd3hNKiRG7HqD/yZytdNRPYixQmTrWfUXl6OqKrDVLcLFILQDefYM1A7IUJhrShfSFRF9A== X-Received: by 2002:adf:965a:: with SMTP id c26-v6mr22096254wra.197.1529591502947; Thu, 21 Jun 2018 07:31:42 -0700 (PDT) Received: from gmail.com (2E8B0CD5.catv.pool.telekom.hu. [46.139.12.213]) by smtp.gmail.com with ESMTPSA id e13-v6sm7512328wrm.45.2018.06.21.07.31.41 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 21 Jun 2018 07:31:42 -0700 (PDT) Date: Thu, 21 Jun 2018 16:31:40 +0200 From: Ingo Molnar To: Mike Snitzer Cc: Thomas Gleixner , Mikulas Patocka , Dan Williams , device-mapper development , X86 ML , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 RESEND] x86: optimize memcpy_flushcache Message-ID: <20180621143140.GA14095@gmail.com> References: <20180519052503.325953342@debian.vm> <20180519052631.730455475@debian.vm> <20180524182013.GA59755@redhat.com> <20180618132306.GA25431@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180618132306.GA25431@redhat.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Mike Snitzer wrote: > From: Mikulas Patocka > Subject: [PATCH v2] x86: optimize memcpy_flushcache > > In the context of constant short length stores to persistent memory, > memcpy_flushcache suffers from a 2% performance degradation compared to > explicitly using the "movnti" instruction. > > Optimize 4, 8, and 16 byte memcpy_flushcache calls to explicitly use the > movnti instruction with inline assembler. Linus requested asm optimizations to include actual benchmarks, so it would be nice to describe how this was tested, on what hardware, and what the before/after numbers are. Thanks, Ingo