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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 D4647C433E0 for ; Wed, 3 Jun 2020 18:45:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B42E92074B for ; Wed, 3 Jun 2020 18:45:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="TV9ewfNU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726134AbgFCSpK (ORCPT ); Wed, 3 Jun 2020 14:45:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbgFCSpK (ORCPT ); Wed, 3 Jun 2020 14:45:10 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8D5C9C08C5C0 for ; Wed, 3 Jun 2020 11:45:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=AiPy53V6h1Oivo7tu+n6fDJ5NKi04giFj6hhH9RvvlU=; b=TV9ewfNUh79JaBAZMDU3270/0 ZLCM2o1/xx5N2WSSyVShNt421sz8OXHZG2vgWPq5noPugob+kd0PeBUZVCYrr8UI7uSwVXHqhyNcO RfP9L1rzOda1bbJnqhg5OsdJuluVKc1RFkgsMQU3n2AiO/Td3CmIxuGOMDTx17r2li7NM8zmhf58v j5aGHivNTRR0vEvG4dhHKk8cOkzJmf54dr5CRv0DNaUPomD7nChe4uHemLk5YWGCI0trtmXe5s+hb SluksW3az6sBMpNqWuo+8uC6YpHzHNkr28H8jU8Ymx+9a9BFJa4m05TGTVNtLdPa++uFMxo79RDxR 1c/ebxjZQ==; Received: from shell.armlinux.org.uk ([2002:4e20:1eda:1:5054:ff:fe00:4ec]:38460) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jgYNr-00066B-76; Wed, 03 Jun 2020 19:45:03 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1jgYNo-0005ce-UV; Wed, 03 Jun 2020 19:45:00 +0100 Date: Wed, 3 Jun 2020 19:45:00 +0100 From: Russell King - ARM Linux admin To: Valentin Schneider Cc: Thara Gopinath , Vincent Guittot , linux-kernel@vger.kernel.org Subject: Re: v5.7: new core kernel option missing help text Message-ID: <20200603184500.GC1551@shell.armlinux.org.uk> References: <20200603173150.GB1551@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 03, 2020 at 07:00:26PM +0100, Valentin Schneider wrote: > > On 03/06/20 18:31, Russell King - ARM Linux admin wrote: > > Hi, > > > > A new kernel configuration option ("SCHED_THERMAL_PRESSURE") was > > recently added, but has no help text. This is most unhelpful when > > trying to configure the kernel, since one does not know what the > > effect of answering yes or no to this option would be. > > > > Please supply a proper help text when adding core kernel options > > so that people can make an informed decision when answering the > > prompt, rather than just guessing. > > > > Right; does the below look good enough? It's a start. I'm still wondering whether I should answer yes or no for the platforms I'm building for. So far, all I've found is: arch/arm/include/asm/topology.h:#define arch_scale_thermal_pressure topology_get_thermal_pressure which really doesn't tell me anything about this. So I'm still in the dark. I guess topology_get_thermal_pressure is provided by something in drivers/ which will be conditional on some driver or something. > > --- > diff --git a/init/Kconfig b/init/Kconfig > index 74a5ac65644f..f40cf852d00a 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -441,6 +441,10 @@ config HAVE_SCHED_AVG_IRQ > config SCHED_THERMAL_PRESSURE > bool "Enable periodic averaging of thermal pressure" > depends on SMP > + help > + This option allows the scheduler to be aware of CPU thermal throttling > + (i.e. thermal pressure), providing arch_scale_thermal_pressure() is > + implemented. > > config BSD_PROCESS_ACCT > bool "BSD Process Accounting" > --- > -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC for 0.8m (est. 1762m) line in suburbia: sync at 13.1Mbps down 424kbps up