Received: by 2002:ac0:a594:0:0:0:0:0 with SMTP id m20-v6csp4679759imm; Fri, 18 May 2018 08:56:35 -0700 (PDT) X-Google-Smtp-Source: AB8JxZo/UIcDtZ6xgvUTm1/0JHGKvsw0QVNAmGP1OKiLoXmmbAUVKBg1+oEmPLtNXWfJdbReyTp5 X-Received: by 2002:a62:ab10:: with SMTP id p16-v6mr9908906pff.211.1526658995885; Fri, 18 May 2018 08:56:35 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1526658995; cv=none; d=google.com; s=arc-20160816; b=XeEtkw1Wjn1uULOvxxuef3vEQF6In7Y0fHCX1FyD74hG8iG8Jjh9e/Jgk1noghYPgW fHpXmLf9j7x1LRZ3L1pUVokzn9g4rBgB27B02KonDsfEUJnHB9VvGQtO0mM4gPGRKtwL uMMtpaQkH3nLqG6VlSH+vL9lRzkOLJVio/RBn4X1ay/w4xTwv8CRVOlZPWJRAnAricwf NROdhWwXETYfYBxdYExV6dxDR/IjPqwmzt+MSVKWM7o8uNGWPluUEFnbiZ8jI7dL5O1W gcNLb527uz7Ok5Pv190kNmYB+monoJRn0D4vHAHT8SgJ96Hqwcy2TK27q9nY6HEPJGdj kF2w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-transfer-encoding:content-disposition:mime-version :references:message-id:subject:cc:to:from:date :arc-authentication-results; bh=jGaZBCX6ewIUP11rxTG51ivTpZ9UOIOVYkGTnnoS2mk=; b=fRasKa5wXQrbwYRv0f1Icy+WMwHm2tBwo1FCNM7UdWlOI2b79Eddq8tVjKe6mHmvCQ Yv9d+zSDFKQrvihMauuWskd8VZfIw8qgHAgHiSxlxTEBGWZcm8ZhenlHE8gCUsJyOByN aCyFiHgSGvn9dO+FA7rR6ClmzTyet8fWkmb1Q/lOgt56BaMiqEVGOAgQc2Vd4xd4iYz9 cJhQ+eiXEvb3RPoazeuQlsTICZiVkbATSM2IuWV+3+DTmKR7EMqPhwXN2JzeExoYQFtw u96udBg4k0wCiZT36y3mvvlOvWxc4ydhGtncBopQSUDELJM2vw1/F9zBHwWTDZYxb/y+ XNaQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id c10-v6si7678081pla.127.2018.05.18.08.56.21; Fri, 18 May 2018 08:56:35 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752242AbeERPyi (ORCPT + 99 others); Fri, 18 May 2018 11:54:38 -0400 Received: from mail.skyhub.de ([5.9.137.197]:38902 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384AbeERPyf (ORCPT ); Fri, 18 May 2018 11:54:35 -0400 X-Virus-Scanned: Nedap ESD1 at mail.skyhub.de Received: from mail.skyhub.de ([127.0.0.1]) by localhost (blast.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id THO8zslmiIKM; Fri, 18 May 2018 17:54:18 +0200 (CEST) Received: from pd.tnic (p200300EC2BC87100E112EAEA647B5E34.dip0.t-ipconnect.de [IPv6:2003:ec:2bc8:7100:e112:eaea:647b:5e34]) (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 879E31EC00EE; Fri, 18 May 2018 17:54:18 +0200 (CEST) Date: Fri, 18 May 2018 17:53:59 +0200 From: Borislav Petkov To: Nadav Amit Cc: Ingo Molnar , Peter Zijlstra , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Josh Poimboeuf , Linus Torvalds , Andy Lutomirski , Peter Zijlstra , Denys Vlasenko Subject: Re: [PATCH 2/6] x86: bug: prevent gcc distortions Message-ID: <20180518155359.GF17285@pd.tnic> References: <20180517161402.78089-1-namit@vmware.com> <20180517161402.78089-3-namit@vmware.com> <20180518075853.GD12217@hirez.programming.kicks-ass.net> <20180518081354.GA11379@gmail.com> <20180518101114.GB17285@pd.tnic> <20180518154044.GE17285@pd.tnic> <30EDFE9B-CA25-42EE-A57F-E3054B84223E@vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <30EDFE9B-CA25-42EE-A57F-E3054B84223E@vmware.com> User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 18, 2018 at 03:46:33PM +0000, Nadav Amit wrote: > In case you didn’t read the cover-letter: the patch-set does give a 2% > performance improvement for #PF-MADV_DONTNEED microbenchmark loop. I saw it but *micro*-benchmark doesn't tell me a whole lot. If that "improvement" is not visible in real workloads/benchmarks, then I'm just as unimpressed. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.