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=-11.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham 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 84104C10F0E for ; Tue, 9 Apr 2019 07:36:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 529622083E for ; Tue, 9 Apr 2019 07:36:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726646AbfDIHgK (ORCPT ); Tue, 9 Apr 2019 03:36:10 -0400 Received: from mx2.suse.de ([195.135.220.15]:39446 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726001AbfDIHgJ (ORCPT ); Tue, 9 Apr 2019 03:36:09 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 37874B02C; Tue, 9 Apr 2019 07:36:08 +0000 (UTC) Date: Tue, 9 Apr 2019 09:36:07 +0200 From: Petr Mladek To: Josh Poimboeuf Cc: Miroslav Benes , yamada.masahiro@socionext.com, michal.lkml@markovi.net, jikos@kernel.org, joe.lawrence@redhat.com, ggherdovich@suse.cz, linux-kbuild@vger.kernel.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled Message-ID: <20190409073607.ms4amehc23quaio3@pathway.suse.cz> References: <20190404184411.1392-1-mbenes@suse.cz> <20190404201855.xtvtgxaaomcmowrt@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190404201855.xtvtgxaaomcmowrt@treble> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 2019-04-04 15:18:55, Josh Poimboeuf wrote: > On Thu, Apr 04, 2019 at 08:44:11PM +0200, Miroslav Benes wrote: > > GCC 9 introduces a new option, -flive-patching. It disables certain > > optimizations which could make a compilation unsafe for later live > > patching of the running kernel. > > > > The option is used only if CONFIG_LIVEPATCH is enabled and $(CC) > > supports it. > > > > Performance impact of the option was measured on three different > > Intel machines - two bigger NUMA boxes and one smaller UMA box. Kernel > > intensive (IO, scheduling, networking) benchmarks were selected, plus a > > set of HPC workloads from NAS Parallel Benchmark. The tests were done on > > upstream kernel 5.0-rc8 with openSUSE Leap 15.0 userspace. > > > > The majority of the tests is unaffected. The only significant exception > > is the scheduler section which suffers 1-3% degradation. > > > > Evaluated-by: Giovanni Gherdovich > > Signed-off-by: Miroslav Benes > > --- > > The patch is based on master branch of the livepatching tree on > > git.kernel.org. > > > > Many thanks to Giovanni who ran the whole testing campaign and analyzed > > the results. I archived the dashboard and detailed data. If anyone is > > interested, we could probably set up a public website somewhere. > > Acked-by: Josh Poimboeuf I have committed the patch into the branch for-5.2/core. Best Regards, Petr