Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754361AbcDDGs3 (ORCPT ); Mon, 4 Apr 2016 02:48:29 -0400 Received: from mail-lb0-f173.google.com ([209.85.217.173]:34802 "EHLO mail-lb0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752105AbcDDGs1 (ORCPT ); Mon, 4 Apr 2016 02:48:27 -0400 Subject: Re: [PATCH] x86: Add a turbo mode sysctl To: Andy Lutomirski , x86@kernel.org References: Cc: Borislav Petkov , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org From: Nikolay Borisov Message-ID: <57020E37.4000302@kyup.com> Date: Mon, 4 Apr 2016 09:48:23 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1142 Lines: 26 On 04/01/2016 06:49 PM, Andy Lutomirski wrote: > Sadly, hardware turbo mode buttons are few and far between in these > degenerate times. Add a software control at /proc/sys/turbo_mode. > > Unfortunately, Linux graphical environments have become very > heavy-weight and are essentially unusable on non-Turbo systems. The > VT console works very well, though. > > Due to KVM limitations, turbo mode is permanently on in a KVM guest. > > Signed-off-by: Andy Lutomirski > --- > arch/x86/mm/pat.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 61 insertions(+), 2 deletions(-) The name of the sysctl really sucks, it just control whether caching is enabled/disabled. Now, having said that I realize there are multiple sysctl that contain "cache" in their names. But can you come up with a more descriptive name, directly relating to what the sysctl does and now what its actual effects are :)? Also, aren't caches enabled by the kernel when the system is booting, according to SDM1/section 9.3 caches are disabled after reset and I assume the kernel does enable them when it's booting?