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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1FC17C00140 for ; Thu, 18 Aug 2022 20:52:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A4CE88D0003; Thu, 18 Aug 2022 16:52:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9FBDF8D0002; Thu, 18 Aug 2022 16:52:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C3088D0003; Thu, 18 Aug 2022 16:52:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 78C298D0002 for ; Thu, 18 Aug 2022 16:52:40 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 418801223A0 for ; Thu, 18 Aug 2022 20:52:40 +0000 (UTC) X-FDA: 79813912038.03.351A6C0 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf01.hostedemail.com (Postfix) with ESMTP id ED9AC432A6 for ; Thu, 18 Aug 2022 20:19:41 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7BE98B821CE; Thu, 18 Aug 2022 17:11:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2644C433D7; Thu, 18 Aug 2022 17:11:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660842708; bh=Mc/teE1LL9vULZCSDU4ycYT9u3eYQsCxpUOtyauN4pA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AWZJlPCUjq7p7vu1Bz1r9kJMchqJkGqlekx/lzPT6Oj4nq7WfVIZWD8OhWHR2XkVX ZnKbvC1td2JxmqeAdI92wUok2KK0c+EGdwAkUYukMT0fkHzjx++xPTyA00oZfxDQsU oObrS3/4Qeb8iKzTN3NRGKr2Hqg0xImh2Zp0BOkmRMrE/lzEOtzH2nV3907a3fZRpf jXcDflt8dDHueJRaAPrBJ+5KerzThkqKlYnEssdtOjzTBPv+jNv7wM7iov/uUCc/Hl agnxm4gTMg5MrPk4VELdphBGUPn8P0x5dNqePLwdV5MNnFfetscJh8KZYrUCkUs/FV Cf5Qi8CnwkXOA== From: SeongJae Park To: Xin Hao Cc: sj@kernel.org, akpm@linux-foundation.org, damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 1/2] mm/damon/lru_sort: Move target memory region check to head of func Date: Thu, 18 Aug 2022 17:11:45 +0000 Message-Id: <20220818171145.51607-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220818105732.34492-2-xhao@linux.alibaba.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660853984; a=rsa-sha256; cv=none; b=lJVasjoROXuRZqGz5wvjZfvLv2/8VIywJkHRJ1hLPGzOINE5/ojtHqqINAf+E2u3yLvCLr dIiKUDSQZWpt77XWcDYBHQd4Ywwvd7ElML24YzZmOUgrZ5mY3GV7tl5WxL+RNWFG4Kpaw9 MNYhCa599Vmrwx5pTseoF9umvLRJhqU= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=AWZJlPCU; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of sj@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=sj@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660853984; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=QWa36h610/rgl45yCN+tlFAx8cX6cB9Od9cwpGPSsPM=; b=ml3ajCS+W+mDjhoSIHf3gJA2PkWe9/asmQ+CDzRNj0qIN4M+0aa4u+38eJpOvLdNhgD3If SIwnNX+EieHm1ClTAJ3nG0ju6NDSHAOPH1YvwCXin2eGnGhEx19Y9EGvPIDDgG02UEXpDH wxJXgc+GtxAKsOBA9u88u64lCu7eL4Y= X-Rspam-User: X-Stat-Signature: r4en8r5f95dx1nxq8bt7ikaq3m6dpczh X-Rspamd-Queue-Id: ED9AC432A6 Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=AWZJlPCU; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf01.hostedemail.com: domain of sj@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=sj@kernel.org X-Rspamd-Server: rspam02 X-HE-Tag: 1660853981-373910 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Xin, On Thu, 18 Aug 2022 18:57:31 +0800 Xin Hao wrote: > In damon_lru_sort_apply_parameters(), if "monitor_region_start" > and "monitor_region_end" is not a valid physical address range, > There no need to run the remainder codes in it. The function, 'damon_lru_sort_apply_parameters()', checks validity of parameters and construct the DAMON context one by one. For example, 'damon_set_attrs()' returns an error if the parameters are invalid. So the intended flow is, 1. check DAMON attributes parameters, 2. apply DAMON attributes parameters, 3. check scheme parameters, 4. apply scheme parameters, 5. check target region parameters, and 6. apply target region parameters. Therefore what this patch does is making the target regions validity check to be done earlier than validity checks of other parameters. There is no special reason to check the region earlier than others. Also, this change makes the flow of the function a little bit weird in my humble opinion, as the flow will be 1. check target region parameters, 2. check DAMON attributes parameters, 3. apply DAMON attributes parameters, 4. check scheme parameters, 5. apply scheme parameters, and 6. apply target region parameters. So I'd argue this patch seems not really needed, sorry. Thanks, SJ [...]