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=-12.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 32D6CC49EA7 for ; Fri, 25 Jun 2021 06:17:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1403F61421 for ; Fri, 25 Jun 2021 06:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233175AbhFYGUA (ORCPT ); Fri, 25 Jun 2021 02:20:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:30284 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230192AbhFYGT4 (ORCPT ); Fri, 25 Jun 2021 02:19:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624601856; h=from:from:reply-to: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=DluuXyEXbo7ekrnZZANuEGrKYi0ROoHqwgYQSQdvpuQ=; b=RVUaJV4rW6V+BEUS0KXAumu2wlqOwuoydDDp+F1qhbl4fVCMvA12nm8xeNvDclOUUrSVeX ZPe/urX/qEQujRi1J+L9p5KvTmrEjRDehZiSxFyReHVyhyOI/0D4yRBD1KTHnfPVRdm43a dPRlSd6ciX/LEYO0cZnUKhvgEH/dCdY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-263-o31io9nmNeWVMxnLQIIOMA-1; Fri, 25 Jun 2021 02:17:34 -0400 X-MC-Unique: o31io9nmNeWVMxnLQIIOMA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 261F0804140; Fri, 25 Jun 2021 06:17:33 +0000 (UTC) Received: from [10.64.54.233] (vpn2-54-233.bne.redhat.com [10.64.54.233]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9BAC05D6AB; Fri, 25 Jun 2021 06:17:25 +0000 (UTC) Reply-To: Gavin Shan Subject: Re: [PATCH v5 0/4] mm/page_reporting: Make page reporting work on arm64 with 64KB page size To: "Michael S. Tsirkin" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, alexander.duyck@gmail.com, david@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, catalin.marinas@arm.com, will@kernel.org, shan.gavin@gmail.com References: <20210625042150.46964-1-gshan@redhat.com> <20210625015826-mutt-send-email-mst@kernel.org> From: Gavin Shan Message-ID: Date: Fri, 25 Jun 2021 16:17:22 +1000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <20210625015826-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/25/21 3:58 PM, Michael S. Tsirkin wrote: > On Fri, Jun 25, 2021 at 12:21:46PM +0800, Gavin Shan wrote: >> The page reporting threshold is currently equal to @pageblock_order, which >> is 13 and 512MB on arm64 with 64KB base page size selected. The page >> reporting won't be triggered if the freeing page can't come up with a free >> area like that huge. The condition is hard to be met, especially when the >> system memory becomes fragmented. >> >> This series intends to solve the issue by having page reporting threshold >> as 5 (2MB) on arm64 with 64KB base page size. The patches are organized as: >> >> PATCH[1/4] Fix some coding style in __page_reporting_request(). >> PATCH[2/4] Represents page reporting order with variable so that it can >> be exported as module parameter. >> PATCH[3/4] Allows the device driver (e.g. virtio_balloon) to specify >> the page reporting order when the device info is registered. >> PATCH[4/4] Specifies the page reporting order to 5, corresponding to >> 2MB in size on ARM64 when 64KB base page size is used. > > I sent comments on v4. They still apply I think. Want me to repeat them > here? > Thanks for your comments, Michael. I've replied to your comments through v4. There are some future work as Alex and David pointed out before: In order to remove the hack in virtio-memballoon, the VMM needs to report the page reporting order. I will keep working on this when I have spare time. Thanks, Gavin >> Changelog >> ========= >> v5: >> * Restore @page_reporting_order to @pageblock_order when >> device is registered in PATCH[2/4] to keep "git bisect" >> friendly at least. (Alex) >> v4: >> * Set @page_reporting_order to MAX_ORDER. Its value is >> specified by the driver or falls back to @pageblock_order >> when page reporting device is registered. (Alex) >> * Include "module.h" in page_reporting.c (Andrew) >> v3: >> * Avoid overhead introduced by function all (Alex) >> * Export page reporting order as module parameter (Gavin) >> v2: >> * Rewrite the patches as Alex suggested (Alex) >> >> Gavin Shan (4): >> mm/page_reporting: Fix code style in __page_reporting_request() >> mm/page_reporting: Export reporting order as module parameter >> mm/page_reporting: Allow driver to specify reporting >> virtio_balloon: Specify page reporting order if needed >> >> .../admin-guide/kernel-parameters.txt | 6 +++++ >> drivers/virtio/virtio_balloon.c | 17 ++++++++++++++ >> include/linux/page_reporting.h | 3 +++ >> mm/page_reporting.c | 22 +++++++++++++++---- >> mm/page_reporting.h | 5 ++--- >> 5 files changed, 46 insertions(+), 7 deletions(-) >> >> -- >> 2.23.0 >