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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 D0EAFC18E5C for ; Tue, 10 Mar 2020 11:56:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A768E24680 for ; Tue, 10 Mar 2020 11:56:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="HEVK8xf5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726486AbgCJL4c (ORCPT ); Tue, 10 Mar 2020 07:56:32 -0400 Received: from smtp-fw-9102.amazon.com ([207.171.184.29]:36263 "EHLO smtp-fw-9102.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726252AbgCJL4c (ORCPT ); Tue, 10 Mar 2020 07:56:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1583841392; x=1615377392; h=from:to:cc:subject:date:message-id:in-reply-to: mime-version; bh=XgE7fl2rsu1FY7ZdIVhp6neAOLJV5gIrJsW3gETU0eM=; b=HEVK8xf50yNJCWCslyH5qH7VsjfplPeENWOnOla3jcP8gwZ4ZCL1l0q4 T8cocqDUSYFDBgLOxxqQCAyBbHdnkjjHszR213oeMuJ/0aJAgCHoTCE2L A1ICcn90vLlupGYRp4hlqlSVLspu6y6NhurXoEOpxld9mTEoGzdhMzLjf 8=; IronPort-SDR: 0Hzydumc9Ij+7hDen+sL7JUWLL5Ret2Tmu1RWo6Sr1AL94jtdCPeH/n9LuHToof97fSrrZZupW HxW5PLblkjgg== X-IronPort-AV: E=Sophos;i="5.70,536,1574121600"; d="scan'208";a="30315489" Received: from sea32-co-svc-lb4-vlan3.sea.corp.amazon.com (HELO email-inbound-relay-1a-807d4a99.us-east-1.amazon.com) ([10.47.23.38]) by smtp-border-fw-out-9102.sea19.amazon.com with ESMTP; 10 Mar 2020 11:56:28 +0000 Received: from EX13MTAUEA002.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1a-807d4a99.us-east-1.amazon.com (Postfix) with ESMTPS id A4F76A0687; Tue, 10 Mar 2020 11:56:17 +0000 (UTC) Received: from EX13D31EUA001.ant.amazon.com (10.43.165.15) by EX13MTAUEA002.ant.amazon.com (10.43.61.77) with Microsoft SMTP Server (TLS) id 15.0.1236.3; Tue, 10 Mar 2020 11:56:16 +0000 Received: from u886c93fd17d25d.ant.amazon.com (10.43.162.67) by EX13D31EUA001.ant.amazon.com (10.43.165.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 10 Mar 2020 11:56:04 +0000 From: SeongJae Park To: Jonathan Cameron CC: SeongJae Park , , "SeongJae Park" , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: Re: Re: [PATCH v6 06/14] mm/damon: Implement access pattern recording Date: Tue, 10 Mar 2020 12:55:49 +0100 Message-ID: <20200310115550.24668-1-sjpark@amazon.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200310090134.000052fb@Huawei.com> (raw) MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.43.162.67] X-ClientProxiedBy: EX13D16UWB004.ant.amazon.com (10.43.161.170) To EX13D31EUA001.ant.amazon.com (10.43.165.15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Mar 2020 09:01:34 +0000 Jonathan Cameron wrote: > On Mon, 24 Feb 2020 13:30:39 +0100 > SeongJae Park wrote: > > > From: SeongJae Park > > > > This commit implements the recording feature of DAMON. If this feature > > is enabled, DAMON writes the monitored access patterns in its binary > > format into a file which specified by the user. This is already able to > > be implemented by each user using the callbacks. However, as the > > recording is expected to be used widely, this commit implements the > > feature in the DAMON, for more convenience and efficiency. > > > > Signed-off-by: SeongJae Park > > I guess this work whilst you are still developing, but I'm not convinced > writing to a file should be a standard feature... I also not sure whether this is right feature of the kernel or not, but this would minimize many efforts in user space. I also thought that this might be not out of the intention of the 'kernel_write()'. Nonetheless, this patch could be simply removed, as DAMON supports tracepoints and the recording can be implemented on user space using it. Could I ask your other suggestions for this feature? Thanks, SeongJae Park > > > --- [...]