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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 ED89CC433EF for ; Thu, 9 Sep 2021 10:45:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C765561051 for ; Thu, 9 Sep 2021 10:45:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234315AbhIIKqL (ORCPT ); Thu, 9 Sep 2021 06:46:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233654AbhIIKqK (ORCPT ); Thu, 9 Sep 2021 06:46:10 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D72B2C061575 for ; Thu, 9 Sep 2021 03:45:00 -0700 (PDT) Received: from zn.tnic (p200300ec2f0e4500a512d950ff073124.dip0.t-ipconnect.de [IPv6:2003:ec:2f0e:4500:a512:d950:ff07:3124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 29BA91EC04EC; Thu, 9 Sep 2021 12:44:55 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1631184295; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=2anM/ZbPy6i25eNR9NW1BBBJS1d08PRuyDbsiqAMPTg=; b=omGA+tKYR5akh5u03TZoPcZRf9uRod1Dry1cD4AVwHZWZVna0RoWAYD1LcJvUqRiqC1cLJ D9qXonE7fj0qOX6F0mPWNKzkWSPZuHOUH6wgETnggIaVhBhcYEKwmZPm2xqRQejsNseZuu IbOGiSO13OU0/4M5GVMOmEEe0UdiuyI= Date: Thu, 9 Sep 2021 12:44:46 +0200 From: Borislav Petkov To: Luming Yu Cc: Jinhua Wu , the arch/x86 maintainers , zelin.deng@linux.alibaba.com, jiayu.ni@linux.alibaba.com, Andi Kleen , Luming Yu , fan.du@intel.com, artie.ding@linux.alibaba.com, "Luck, Tony" , Thomas Gleixner , LKML , pawan.kumar.gupta@linux.intel.com, "Yu, Fenghua" , "H. Peter Anvin" , ricardo.neri-calderon@linux.intel.com, Peter Zijlstra Subject: Re: [PATCH] perf: optimize clear page in Intel specified model with movq instruction Message-ID: References: <1631177151-53723-1-git-send-email-wujinhua@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 09, 2021 at 06:34:40PM +0800, Luming Yu wrote: > do you mean jump label would not be replaced to nop when its key is enabled? > so we could not use it in certain functions? > I don't understand exactly what "ain't gonna happen" It means, you need to use an X86_FEATURE_ bit because I won't accept a static key. But do the benchmarks first. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette