Received: by 2002:a05:6a10:17d3:0:0:0:0 with SMTP id hz19csp354289pxb; Wed, 14 Apr 2021 17:37:33 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwzh6U/j7zbsGaljDSrFaagvbO+qtRYt+BsaGMrtnjvZDOaTCpcHtrJVAzX3cAWjDf8R/do X-Received: by 2002:a63:3d48:: with SMTP id k69mr911086pga.239.1618447053281; Wed, 14 Apr 2021 17:37:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1618447053; cv=none; d=google.com; s=arc-20160816; b=dcc+lEVJ9u8zpzHxnYsQkxdexVtypU2uhJwnHmAYDTeEjwBYfDH++isCmBh/rrRPOc mEkj2/2pPXkMtmO8q40cNkkKB0Hz/hzAbkDRckuetrbBnYvCvbVn1Zl0BX3FBu3pa4c3 pfQ2+bYraIsVS9lkwdjtYAtfNRQisdSgjZAtWKTFWi7umOcyyARF4rxGnxIiIEjumHwh 0dMvXDHuQIHsmyZYOWpFCA19eqy1Y+fKS6Su+91Xue0BK5SFNmObirE7hVOzyd8OI9Gj 1Csw5uBXaZz9KAfYWLJnOo0EYfMHDAPbnSqg+XvD8a5oS8xJ45ggRoJSjgwkU2ZzxvB8 qYWg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-language:content-transfer-encoding :in-reply-to:mime-version:user-agent:date:message-id:references:cc :to:subject:from:dkim-signature; bh=Pwu8ITVpaktX/oaFXebOFcED+CIuIn8065SfkxgfWGI=; b=jiyM87G3O+hCWoa2c9cCQgBenife4EbxZWWr9U8VVTFrTdk0M30vuDZPVcptZsUQHp 1Q2p9kTeU64siIdE6aqOxiMlbrc0fqqnMVNF1FoO6tC786F4aelWp4aKUjYuYcitXxHv p30S7/zHbKelsDI4GfRPbzMmasQ7A9EP5W7p8mVqjPCA/oI9aXR7h/62VH/wMUjPKaqd 9SWFMynD621TcwwTVm60wTdjnFXUrxoJp7+YktDeWSHLHuIxWN87QJ+4lb1F1a/mbWD6 GyR879JO4qz4JmaU3Z0CB6x/+pgAt4ZOrhb0jIpY+9Zq5gMJblkgOT1/SbkmJ/HPQ73k s5Aw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=foQvjc3s; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id w82si1182573pff.61.2021.04.14.17.37.04; Wed, 14 Apr 2021 17:37:33 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=foQvjc3s; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350540AbhDNRbv (ORCPT + 99 others); Wed, 14 Apr 2021 13:31:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:54748 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350698AbhDNRbo (ORCPT ); Wed, 14 Apr 2021 13:31:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618421482; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Pwu8ITVpaktX/oaFXebOFcED+CIuIn8065SfkxgfWGI=; b=foQvjc3s0ZEtrldIiYePQl5xO747Hgz0vu3XoGP1TESxsTOaU0pU4qU6w9KNZzl+jEFwxl 83ed0eLAcxRthubRE+GmYpo+2WGg9UYKaDYLdc+ZUfqtu8cjb8/5JYHTOJGtJ8Wt/hO77O mhgfRvLkrafo9ddZhkIFTWT38lA+cM0= Received: from mail-qk1-f197.google.com (mail-qk1-f197.google.com [209.85.222.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-183-CQdCdmyNPYaUUY8SfeIT7A-1; Wed, 14 Apr 2021 13:31:21 -0400 X-MC-Unique: CQdCdmyNPYaUUY8SfeIT7A-1 Received: by mail-qk1-f197.google.com with SMTP id o4so4954878qkg.2 for ; Wed, 14 Apr 2021 10:31:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=Pwu8ITVpaktX/oaFXebOFcED+CIuIn8065SfkxgfWGI=; b=fyyIkFgT8BjKok7FLE9VEriiPvKZhbB4J0L5v+ulojfr39RyptSqy8GA8yHUVzYJbV xD2P01jPXI/5qAz1MO1JAoXOctUCicv4vyTMg5qFE05LVKXI+88VJaWK9WMcPxOv9jCD Jv5e0TQ8d1n9BhpeP2iO2URGIAtn8bVmN35abiZs05Wc4JeRQLELlGzdYTSfY8PCY2sQ 0T+56pLeAuOIlREpPgOaF1Nwct/jWRXYwBZoOD8HNq9hglSf/MpEEiGKTKz1t4pj8GBK ZFrbMwYEcjmyYjg7LUKUNh2nCIK3xqBW90rHvo+6WKrhQ4lzAbCA7USlWbbGcdAq22Km G4HQ== X-Gm-Message-State: AOAM530X/S0RyeFzfURVw2y/4GqVRt+mIbu//PBzEgZ1K3xSEXPU83eu rq7gzQHCbiTRsKuc8c46J+nwyyRF+6gTia+TEzWw4Uy8VQyQD07irXCRhUXg0b1jZskebXzI6O5 pKxl0zb1IubPAyo3yoHG4oq0H X-Received: by 2002:ae9:dcc1:: with SMTP id q184mr6147240qkf.482.1618421480631; Wed, 14 Apr 2021 10:31:20 -0700 (PDT) X-Received: by 2002:ae9:dcc1:: with SMTP id q184mr6147223qkf.482.1618421480434; Wed, 14 Apr 2021 10:31:20 -0700 (PDT) Received: from llong.remote.csb ([2601:191:8500:76c0::cdbc]) by smtp.gmail.com with ESMTPSA id t17sm18505qtr.42.2021.04.14.10.31.18 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 14 Apr 2021 10:31:19 -0700 (PDT) From: Waiman Long X-Google-Original-From: Waiman Long Subject: Re: [External] : Re: [PATCH v14 4/6] locking/qspinlock: Introduce starvation avoidance into CNA To: Andi Kleen , Waiman Long Cc: Alex Kogan , linux@armlinux.org.uk, Peter Zijlstra , Ingo Molnar , will.deacon@arm.com, arnd@arndb.de, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, bp@alien8.de, hpa@zytor.com, x86@kernel.org, guohanjun@huawei.com, jglauber@marvell.com, steven.sistare@oracle.com, daniel.m.jordan@oracle.com, dave.dice@oracle.com References: <20210401153156.1165900-1-alex.kogan@oracle.com> <20210401153156.1165900-5-alex.kogan@oracle.com> <87mtu2vhzz.fsf@linux.intel.com> <4a9dbfa7-db68-a2dc-9018-a5b74f0f421c@redhat.com> <20210414172602.GW3762101@tassilo.jf.intel.com> Message-ID: <6c968acd-dda2-ed1f-6582-b7811030761e@redhat.com> Date: Wed, 14 Apr 2021 13:31:17 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20210414172602.GW3762101@tassilo.jf.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/14/21 1:26 PM, Andi Kleen wrote: >> The CNA code, if enabled, will be in vmlinux, not in a kernel module. As a >> result, I think a module parameter will be no different from a kernel >> command line parameter in this regard. > You can still change it in /sys at runtime, even if it's in the vmlinux. I see, thank for the clarification. Cheers, Longman