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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 D711AC07E96 for ; Tue, 6 Jul 2021 09:27:10 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 99A3D613C8 for ; Tue, 6 Jul 2021 09:27:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 99A3D613C8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.150957.279051 (Exim 4.92) (envelope-from ) id 1m0hLy-00066E-6O; Tue, 06 Jul 2021 09:26:54 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 150957.279051; Tue, 06 Jul 2021 09:26:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m0hLy-000667-3K; Tue, 06 Jul 2021 09:26:54 +0000 Received: by outflank-mailman (input) for mailman id 150957; Tue, 06 Jul 2021 09:26:52 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m0hLw-000661-Dy for xen-devel@lists.xenproject.org; Tue, 06 Jul 2021 09:26:52 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1m0hLw-0005ll-5c; Tue, 06 Jul 2021 09:26:52 +0000 Received: from [54.239.6.188] (helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1m0hLw-0008BW-0B; Tue, 06 Jul 2021 09:26:52 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=jWt1PDEr3L/f+DrapE6GIy6XGLxgxscGH5uM7hfoQ6o=; b=aWmVZpZ0ujytDOZNMXSWiJoo+f KgDr+hC7o8QLXtKP02urxChyOeuWZMxZunske3RZknwpbk2JjWgk7JB9oqx5umfWBXKvMGhYx8ILc CQ7BX2eE1RUHgjz8Utkx1J38VXHu3qXqJ87rldJFHWXyC5+B7nIBV7a+mpfipzURGFdM=; Subject: Re: [PATCH 4/9] xen/arm: static memory initialization To: Penny Zheng , "xen-devel@lists.xenproject.org" , "sstabellini@kernel.org" Cc: Bertrand Marquis , Wei Chen References: <20210607024318.3988467-1-penny.zheng@arm.com> <20210607024318.3988467-5-penny.zheng@arm.com> <1c6530bf-a362-0993-c4c5-953ee2afb1bf@xen.org> From: Julien Grall Message-ID: Date: Tue, 6 Jul 2021 10:26:50 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit On 06/07/2021 10:20, Penny Zheng wrote: > Hi Julien Hi Penny, >> -----Original Message----- >> From: Julien Grall >> Sent: Tuesday, July 6, 2021 5:10 PM >> To: Penny Zheng ; xen-devel@lists.xenproject.org; >> sstabellini@kernel.org; jbeulich@suse.com >> Cc: Bertrand Marquis ; Wei Chen >> >> Subject: Re: [PATCH 4/9] xen/arm: static memory initialization >> >> >> >> On 05/07/2021 08:28, Penny Zheng wrote: >>> Hi Julien >> >> Hi Penny, >> >>>> -----Original Message----- >>>> From: Julien Grall >>>> Sent: Thursday, July 1, 2021 2:10 AM >>>> To: Penny Zheng ; >>>> xen-devel@lists.xenproject.org; sstabellini@kernel.org; >>>> jbeulich@suse.com >>>> Cc: Bertrand Marquis ; Wei Chen >>>> >>>> Subject: Re: [PATCH 4/9] xen/arm: static memory initialization >>>> >>>> Hi Penny, >>>> >>>> On 07/06/2021 03:43, Penny Zheng wrote: >>>>> This patch introduces static memory initialization, during system >>>>> RAM boot >>>> up. >>>> >>>> The word "RAM" looks spurious. >>>> >>> >>> Thx. I check the "spurious" in dictionary, it means fake? So I will leave >> "during system boot up" >>> here. >> >> Yes, this reads better. >> >>>>> 2. scrub the page in need synchronously. >>>> >>>> Can you explain why this is necessary? >>>> >>> >>> Since I'm borrowing the logic in free_heap_pages, I'm also trying to cover all >> the scenarios here like it does. >>> So I assume that free_staticmem_page will not only be used on initialization, >> but also when destroying/rebooting the domain. >>> On these cases, it is necessary to scrub the page, ig. >> >> I wasn't asking about scrubbing specifically but instead why it is synchronous. >> Sorry for the confusion. >> > > I've read asynchronous scrubbing in buddy allocator, pages that need a scrub are added to tail, > and specific working thread is working on it, hmm, imo, I don't think it could be simply applied into static > memory. :/ I am not sure to understand why the same concept can't be applied. Anyway, what I am asking is to clarify in the commit message why this is synchronous (e.g. this just temporary). > > So I put asynchronous scrubbing in #TODO. We seem to have quite a few TODOs (some of them are implicit). Can we start to gather a list of what's missing? A first good place would be the cover lette.r Cheers, -- Julien Grall