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 9A0C6C02180 for ; Mon, 13 Jan 2025 20:02:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E77966B0095; Mon, 13 Jan 2025 15:02:57 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E27F96B0096; Mon, 13 Jan 2025 15:02:57 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CEF126B0098; Mon, 13 Jan 2025 15:02:57 -0500 (EST) 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 B08766B0095 for ; Mon, 13 Jan 2025 15:02:57 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 625C81602CF for ; Mon, 13 Jan 2025 20:02:57 +0000 (UTC) X-FDA: 83003501994.01.47606C8 Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by imf23.hostedemail.com (Postfix) with ESMTP id B328E140002 for ; Mon, 13 Jan 2025 20:02:55 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=URA+RzvM; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf23.hostedemail.com: domain of sj@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=sj@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1736798575; a=rsa-sha256; cv=none; b=xm9eWvr026wjnzxFjl7CQgxnYlIchZysZzzwUejKxnESo4JO34jqKlBRxicsnoDikOFutH 39zv4DSdKhSbWc+VJDixI01vCseQ2r2v+Ah56YVvjVmZ7c2QNPXuZcwvlq8wq+RsWxopDN jpJaQkTyQh2yIBjjN/cL5wp0TwX2k2w= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=URA+RzvM; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf23.hostedemail.com: domain of sj@kernel.org designates 147.75.193.91 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=1736798575; 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=XW1nCCIsmv1Bf92nVaM5tc4Xyv8mKs1BkiyrtKbIiLY=; b=FIkN4Q6/KgVZp5BJPUlgmfu95n1ftzKYsezuuCnfU0FxAuN9K6505pc0nb3fvWoEQhvLMB YV5lISJFhCVZOXz9ELg8JzagLEvFaAiouyDkAssvesSqnV6XJHQOBc6s5koCWyRqQ06C0k MeCZQ819mna4X6A/QaO0aJGqtzzexQQ= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id AD5B8A4135F; Mon, 13 Jan 2025 20:01:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 622D6C4CED6; Mon, 13 Jan 2025 20:02:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736798574; bh=AyPqzFgA4xVjhERkJaxYAdaaqP+fpWVx7YEtFbuSgdo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=URA+RzvMsQE3gAX1Plcekf0VYBJ+KmC9LyNEarFm0v9PdU0tikGhiZsTVDVYopuWr j+73yrvcEObaT3CGvqOQeoT/f/bNYg2g4Z71UjAP0+ERMBDFCAwsnIeybwJPhDTr0i VUlMbqZPPLcdIFSrXx6+Ky2tIAgnuoa0OJKCa/jvtlw1IqFgV6k5oW+gdE1Ae1WCHu ijz4yIrFkCvB3Tfy2W6I7GNHgWu7s4+OtTVopz3pfG1qjKItyQgLk+W4HB3RKZ8tWG +l733JnUrIY32tNqCGz/vwKGz6wzFdbdYRKftY3mHGGe++PNZ7rPUGPPM+kRwBBb83 +eACKJGgtutig== From: SeongJae Park To: Joshua Hahn Cc: SeongJae Park , kernel-team@meta.com, damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 07/18] mm/damon/paddr: report filter-passed bytes back for DAMOS_STAT action Date: Mon, 13 Jan 2025 12:02:52 -0800 Message-Id: <20250113200252.38124-1-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250113194939.4152203-1-joshua.hahnjy@gmail.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: B328E140002 X-Stat-Signature: b4k8nkytbfttw478yjy8yu84f8kidgs7 X-HE-Tag: 1736798575-966360 X-HE-Meta: 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 pNWgMkcI aobarr7HaFzSZtSZlGD+C+PQ1vx0wvFfBidGOg5dMh2cIaRNKCaKXYwOwKPBHgbzgKG1SSjHtxJW9pxeCFZnFylO+cZabfGAohoKLnY+lCqPTYFd+hc59vvWHtUTuiwGndlnJxYoxqZUHR6QN6etkQ4RWZdU0SH8mAVjmAs1qE18BxZrKkOra/Lm7clPoY04chVoK/Q0mzZjlpGOXgaEC8cR56MDfhISgfCBecZSxb/yQ+wyRySvsEK0tm6X21I9Jh9+Ex7xDGEg6i/+OcDwZYQXlR9fe0q4yiOUB2/tMCe1I1gvCJ+oAkD2/dpVe+6TUS8KlYtjFysXu7lBNHYYI9OhPLYl06/dqTdxIffuwzXtr3J+XIrSpbo0fmA1vjxFCaMoubxnM4tvailDAuP6EmcetMw== 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: List-Subscribe: List-Unsubscribe: Hi Joshua, On Mon, 13 Jan 2025 11:49:37 -0800 Joshua Hahn wrote: > On Wed, 18 Dec 2024 20:03:16 -0800 SeongJae Park wrote: > > Hello SJ, > I hope you are doing well! Sorry to add noise to an old mail, but I recently > saw Usama's patch that improves this function, and it brought my attention > to this series, so I have been reading it today. > > I was unsure if I should send this mail because I had a nit / naive question > about the patch: > > [...snip...] > > > +static unsigned long damon_pa_stat(struct damon_region *r, struct damos *s, > > + unsigned long *sz_filter_passed) > > +{ > > + unsigned long addr; > > + LIST_HEAD(folio_list); > > + > > + if (!damon_pa_scheme_has_filter(s)) > > + return 0; > > + > > + for (addr = r->ar.start; addr < r->ar.end; addr += PAGE_SIZE) { > > + struct folio *folio = damon_get_folio(PHYS_PFN(addr)); > > + > > + if (!folio) > > + continue; > > + > > + if (damos_pa_filter_out(s, folio)) > > + goto put_folio; > > + else > > + *sz_filter_passed += folio_size(folio); > > +put_folio: > > + folio_put(folio); > > + } > > + return 0; > > Is there a reason that we decide to use a goto statement here? There was no special reason. I wrote this function by copying damon_pa_migrate() and removing parts that not necessary. As a result, the weird 'goto' has remained. > As far as I > can tell, this is the only place this goto statement is used, and the else > case bleeds into it as well. That is, I believe that the following could be > more readable: > > if (!damos_pa_filter_out(s, folio)) > *sz_filter_passed += folio_size(folio); > > folio_put(folio); > } > return 0; I agree. This looks much better! If you don't mind, pleae send a patch! > > [...snip...] > > Again, I am sorry if this is a naive question. No worry, thank you for this nice and important question! I believe readability matters and DAMON code needs many helps for that :) > Thank you for your time, > I hope you have a great day! You too! Thanks, SJ [...]