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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E91AC7EE2E for ; Sat, 10 Jun 2023 07:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230248AbjFJHZf (ORCPT ); Sat, 10 Jun 2023 03:25:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229538AbjFJHZd (ORCPT ); Sat, 10 Jun 2023 03:25:33 -0400 Received: from mout.gmx.net (mout.gmx.net [212.227.17.22]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E3C43AA5; Sat, 10 Jun 2023 00:25:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.com; s=s31663417; t=1686381928; x=1686986728; i=quwenruo.btrfs@gmx.com; bh=QM0tTvmFEhJ+GkH/S1MQHk4ekROqIAIwT56z2eHMY10=; h=X-UI-Sender-Class:Date:Subject:To:Cc:References:From:In-Reply-To; b=kA7p7u7isUX29FrshrWrCaKfsOY/1izYca2o3LyVShlbSC5yMtj+xGk8H9ACaYLS6z2xMFc Dlof+NE/eV4PlX3ZyfEnYdWP68IL05VFlhR6//C79fiFD/SsQNOpJmLayI0+PXW5vXOSaJTJC IOD27/8Afn0Z1V5eutbsqrE2ICE8h8+uW9kH8UCb4SOjt7JU0NNrZtIFRKKpBKs9mPymbIzgS KfnSQOQDpGj2JwDMhz8fgebigZnl0A0PT5NziyjLiyAiBcZsvP1hFztmxe2gjBp7SmQYPqL6E nIpgHs6hK1t67GU+rJQyCjeJSpF/p63QuKVFGI+aLcSfDCOCZ/OA== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MPXhK-1qUWQv3Uva-00MfeE; Sat, 10 Jun 2023 09:25:28 +0200 Message-ID: <24cfe56a-9d06-4db6-73ab-e413fee3d61f@gmx.com> Date: Sat, 10 Jun 2023 15:25:24 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Subject: Re: [PATCH RFC] common/btrfs: use _scratch_cycle_mount to ensure all page caches are dropped Content-Language: en-US To: Zorro Lang , Qu Wenruo Cc: linux-btrfs@vger.kernel.org, fstests@vger.kernel.org References: <20230608114836.97523-1-wqu@suse.com> <5790cd5a-04d9-bfe9-a8cc-0c09f784222d@suse.com> <20230610064620.4ovt52l4lcvrijyn@zlang-mailbox> From: Qu Wenruo In-Reply-To: <20230610064620.4ovt52l4lcvrijyn@zlang-mailbox> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:njmNLXrcosAKKG75cDJR1NC2Z3YXb5/4cwVULZi7Swjk1TKfNed IoDUi1GIHwQWMPaUP0U3+f3TcQ4AA7KwwIPQek9jF1LFj+qgDF46CRj7cJYr76HEv4N6HXo j3Kl1iG7J6EaBZEbrWOQAHTw0FaGjjzVRAaBFtC/wRMUNcoQYnPXxECmzgSynCEBpluDjpe pIjszdkusmXAPPrjpRvBg== UI-OutboundReport: notjunk:1;M01:P0:cbVLP+IuwX0=;/4z094ZhUWN4KHuGFM5lquiYEax y1xyFn7aWM1t0mDpx4qi/8wvg0jdzcafONRhxskHmULVCkEkpASANbd0wI1COzCq67a270bYS PAISHcsLoAVDAOnNp9aAnIUGdMfTUwFkJ5mZfQz0uwmF7SeGAO2ZsCBmZYVyVMSO9o3wlOID0 iBwJOxFzl2qHvWZRywf5W/1fJx/VsPxjXtG5L62MlpqkmSn8DdkOTiLxCIM88bydhP3xSLVRJ i8TfkNBnD2LDB04exprX3FJBR1s88iBzm3Sp+ryaSzCqWE0Nl4ZR54MprbJnlhY3sxYf0ZgQo c2gUXvwLbfrKLb+MPZztzUoIO62JTd1yb6/Oa8HSQ4A7FzsCWqgfvXRGOKgS+jAZOEK05/mh+ y9Ar2YHq8Gm5PyREBTrz5EWBYj0TVBRjzecHd6blUk3PA3gy1AA2HrlHhzYgmhoNGYuHLKxIU P1jZ9MmkD+4gWgzpn50do/SDom8qemQt/qUM9RYIbk5uz9EBTDZjX7bD6S57Ut4Twga0yBOGP /P46EXIexHnFyEXIrz8WAprcInO5MW/6X811ST/SdrFGht4e49bstWnOM1LeAs/ENAVXhpp/t Wdpb9QmUnNg/sRQEhbR/+8NmULn9rWoIGqz+1FYT5Z7ytnIM7lcz18IHu4wijMVq5fG96+IVd ztwlMg/5R7DbWey2B3cDMxpC+heTqQBMidPA3ePwtRmtRuc+5Yi6VxraJpHoffb79XvNdxG6H cra/LBhqj3pBVZt+hG4aOTw02L9MEAw85Tn4d2OP77U3uEBOZCBinfgqMTyG+6iccZgv9ERIC cJPhQ90+dnZaehjU2EDPiYGhBWBoXRnMc1TFEUOdImMfTYjUp6xw5VAd/EtgfE5KpDJ0WEFEU PmJSp9NqtZ29LYGqUbXm52TCcUYq7dQ6sHRWZ9iqMv6m1Lw0dthVdeCajC3Ae7yj1iTSMEDPf x4NVHpMqABWGE3/OutvLxfuLLhc= Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2023/6/10 14:46, Zorro Lang wrote: > On Fri, Jun 09, 2023 at 07:57:37AM +0800, Qu Wenruo wrote: >> >> >> On 2023/6/8 20:15, Christoph Hellwig wrote: >>> On Thu, Jun 08, 2023 at 07:48:36PM +0800, Qu Wenruo wrote: >>>> echo 3 > /proc/sys/vm/drop_caches >>>> + # Above drop_caches doesn't seem to drop every pages on aarch64 wit= h >>>> + # 64K page size. >>>> + # So here as a workaround, cycle mount the SCRATCH_MNT to ensure >>>> + # the cache are dropped. >>>> + _scratch_cycle_mount >>> >>> The _scratch_cycle_mount looks ok to me, but if we do that, there is >>> really no point in doing the drop_caches as well. >> >> Yep, we can remove that line. It's mostly a reminder for me to dig out = why >> that drop_caches doesn't work as expected. > > How about leaving a reminder/explanation in comment, remove that real dr= op_caches > line. If no objection, I'll merge this patch with this change. We can reuse the comment in the patch, which is already mentioning drop_caches doesn't always work at least on aarch64. I'm fine dropping the "echo 3 > drop_caches" line. Thanks, Qu > > Thanks, > Zorro > >> >> Thanks, >> Qu >> >