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[23.128.96.18]) by mx.google.com with ESMTP id x2si848197eju.153.2020.09.11.01.59.56; Fri, 11 Sep 2020 02:00:19 -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=@gmail.com header.s=20161025 header.b=Hxpb2Uk3; 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=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725764AbgIKI6s (ORCPT + 99 others); Fri, 11 Sep 2020 04:58:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725554AbgIKI6p (ORCPT ); Fri, 11 Sep 2020 04:58:45 -0400 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 749FDC061573 for ; Fri, 11 Sep 2020 01:58:45 -0700 (PDT) Received: by mail-pg1-x543.google.com with SMTP id 67so6158568pgd.12 for ; Fri, 11 Sep 2020 01:58:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=c8nz9oNcqS43/JX3gIjCU/zwWUctvs6c1e4wLHvLc2Y=; b=Hxpb2Uk3qvJAd3R0XfksSYNI8kdRCaccIUM/VdyS2lkhsMLXtOLRME8qLbuhPRhV7y roW/F/u6PTATgscybfZNaRVTOG7YlC66Fa2gylGkaElmNTELAQA87zHgP5W9HZmKY4kG sia/LM9pLookkv7sYkraeIi7fFQ31KlFVIrzmLg16dlNSOTcCroYiyskRO/yjHZnbv7R z29Bg+AdyZGixBqgba5i6ttcQyhAXy54KqdYGJvzHFHmbQG1tVEBDx1raDCT21FKjprb oYqWHsZEzqTjowkA1WkprF/4s4fiLyDEWd2fPD25icFROAkqHGvBCStRHrKWg1xqH6M8 2OJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=c8nz9oNcqS43/JX3gIjCU/zwWUctvs6c1e4wLHvLc2Y=; b=BHcE1gOj9duu/mQHJjjy4htPCLjkO6XFE/nyFJ+F3VNs0XjeuMscXor7hagevkSS24 0qgP1w5aRFtgaeUeLEsCMwm/irioG3+fJ87ErTurgUhdzOeGZ2aeln0irvawArvXhyg8 IQWfuJMZEmQTfXlHONP6Dwjf2Qd6Vup6fX5sURhgqYyu5Ge4o/ViHNhqKEZOPHCApphP 7hMDA6FFdkUIiz925j4KMeOY3dYsjuTpJ8KkkyID4CEAue9jqOvijHR1yuhPS1iaBa+S OsILFt/6IrWBYHjgNtvBKj+4GgKf6L8AFr2epX+7Yl1KG65vMmh/sXv+Eui55bsYMX1c MBLA== X-Gm-Message-State: AOAM530oGKKOv7m1r/zPDCBkTtQ8DAMk46Ozwy8+uZzZlIHwDnd5OKno n6JJG677uRCUfxTQknLRqmk= X-Received: by 2002:a62:8286:0:b029:13c:1611:6588 with SMTP id w128-20020a6282860000b029013c16116588mr1176188pfd.5.1599814725003; Fri, 11 Sep 2020 01:58:45 -0700 (PDT) Received: from localhost ([2409:10:2e40:5100:6e29:95ff:fe2d:8f34]) by smtp.gmail.com with ESMTPSA id u10sm1600580pfn.122.2020.09.11.01.58.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 11 Sep 2020 01:58:44 -0700 (PDT) Date: Fri, 11 Sep 2020 17:58:41 +0900 From: Sergey Senozhatsky To: Marc Zyngier Cc: yezengruan , Sergey Senozhatsky , will@kernel.org, joelaf@google.com, linux-kernel@vger.kernel.org, suleiman@google.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, "Wanghaibin (D)" Subject: Re: [RFC][PATCH 0/4] arm64:kvm: teach guest sched that VCPUs can be preempted Message-ID: <20200911085841.GB562@jagdpanzerIV.localdomain> References: <20200721041742.197354-1-sergey.senozhatsky@gmail.com> <20200817020310.GA1210848@jagdpanzerIV.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org My apologies for the slow reply. On (20/08/17 13:25), Marc Zyngier wrote: > > It really isn't the same thing at all. You are exposing PV spinlocks, > while Sergey exposes preemption to vcpus. > Correct, we see vcpu preemption as a "fundamental" feature, with consequences that affect scheduling, which is a core feature :) Marc, is there anything in particular that you dislike about this RFC patch set? Joel has some ideas, which we may discuss offline if that works for you. -ss