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 8CAC9C27C4F for ; Tue, 11 Jun 2024 02:28:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EA4846B0089; Mon, 10 Jun 2024 22:28:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E2D6D6B008A; Mon, 10 Jun 2024 22:28:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CA6546B008C; Mon, 10 Jun 2024 22:28:58 -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 A80876B0089 for ; Mon, 10 Jun 2024 22:28:58 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 24B951A11EE for ; Tue, 11 Jun 2024 02:28:58 +0000 (UTC) X-FDA: 82217025156.15.40E068C Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf10.hostedemail.com (Postfix) with ESMTP id 34889C000C for ; Tue, 11 Jun 2024 02:28:54 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf10.hostedemail.com: domain of xiujianfeng@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=xiujianfeng@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1718072936; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+NrUFfOeYzZzCWPuXtKijgWlIY8Q9sBnxpFFo1JIe7E=; b=OUugG+wE0GdsUyjFNeKrcS0dodagUUsq8atrlyXJLPEds0l0hT7R2STXYXG0hUiGqqtMHJ 1W5cVsAPKMk6zndl6c5hoDr14CaQsolL2zhupWZ9vYu0Jq3IaWjPEmP8qRHDeHBTIRm8zk csrhKZG+Lj0snUMChhjcYRsngLofMZs= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf10.hostedemail.com: domain of xiujianfeng@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=xiujianfeng@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1718072936; a=rsa-sha256; cv=none; b=I2xrDaZLntNB92pcAM1JfZJIpFPczbybgUX9inHVOOAEB7psnYhPsAWqQxXQhNyZw+Hkqd M+nlZd3aYRcDEDdrVYSUjNXIbIGoxE5zqfP6c7VMrXqd8YyoA6jDlKmWbM/A3Gpb8eVN4u LfJySJ7yLI92MbdtQO8ysp7mVDa/EkA= Received: from mail.maildlp.com (unknown [172.19.88.194]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4VysvL4xBnz1SBhH; Tue, 11 Jun 2024 10:24:46 +0800 (CST) Received: from dggpeml500023.china.huawei.com (unknown [7.185.36.114]) by mail.maildlp.com (Postfix) with ESMTPS id 95C1514041A; Tue, 11 Jun 2024 10:28:50 +0800 (CST) Received: from [10.67.110.112] (10.67.110.112) by dggpeml500023.china.huawei.com (7.185.36.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Tue, 11 Jun 2024 10:28:50 +0800 Message-ID: <01e9ccca-c266-face-6854-40b2d6020a16@huawei.com> Date: Tue, 11 Jun 2024 10:28:49 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.5.1 Subject: Re: [PATCH v2 -next 1/3] mm/hugetlb_cgroup: identify the legacy using cgroup_subsys_on_dfl() Content-Language: en-US To: Oscar Salvador CC: , , , References: <20240605070133.1941677-1-xiujianfeng@huawei.com> <20240605070133.1941677-2-xiujianfeng@huawei.com> From: xiujianfeng In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.110.112] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpeml500023.china.huawei.com (7.185.36.114) X-Rspamd-Queue-Id: 34889C000C X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: ir5ruwng9prnu9pdn68esfjt6ij59jum X-HE-Tag: 1718072934-188979 X-HE-Meta: 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 gOMjskOh A4h3KlNKdjnLt8vjBOxrWFdJZ5oTHyWM2aEtM5fbWLEz4caruFs27v2mxXygLD04p2d0JGBoIEejXX0IBD+U48HZvN8r2nVMseRvmgf5hITNRXqXf6rK7Zv03RlwTLhBbqtyKSWwaxXLC8v0iaDL0ufuTgjqZ/NE7b7guD5d0/I/1Z6MYVb1iYT1t9UI6Y5nXP2ol/rwb1IBPvAE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2024/6/10 13:03, Oscar Salvador wrote: > On Wed, Jun 05, 2024 at 07:01:31AM +0000, Xiu Jianfeng wrote: >> Currently the numa_stat file encodes 1 into private using the micro >> MEMFILE_PRIVATE() to identify the legacy. Actually, we can use >> cgroup_subsys_on_dfl() instead. This is helpful to handle .private >> in the static array of the comming patch. >> >> Signed-off-by: Xiu Jianfeng > > Reviewed-by: Oscar Salvador > > Nit below: > >> --- >> mm/hugetlb_cgroup.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c >> index e20339a346b9..45f94a869776 100644 >> --- a/mm/hugetlb_cgroup.c >> +++ b/mm/hugetlb_cgroup.c >> @@ -460,7 +460,7 @@ static int hugetlb_cgroup_read_numa_stat(struct seq_file *seq, void *dummy) >> int nid; >> struct cftype *cft = seq_cft(seq); >> int idx = MEMFILE_IDX(cft->private); >> - bool legacy = MEMFILE_ATTR(cft->private); >> + bool legacy = !cgroup_subsys_on_dfl(hugetlb_cgrp_subsys); >> struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq)); >> struct cgroup_subsys_state *css; >> unsigned long usage; >> @@ -839,7 +839,7 @@ static void __init __hugetlb_cgroup_file_legacy_init(int idx) >> /* Add the numa stat file */ >> cft = &h->cgroup_files_legacy[8]; >> snprintf(cft->name, MAX_CFTYPE_NAME, "%s.numa_stat", buf); >> - cft->private = MEMFILE_PRIVATE(idx, 1); >> + cft->private = MEMFILE_PRIVATE(idx, 0); > > Do we still have to set it to '0'? > Is it not by default? > Hi Oscar, Thanks for your review. Not all files care about the value of the second argument of MEMFILE_PRIVATE(), but all files care about the value of the first argument 'idx', so the .private must be explicitly set, and passing 0 as the second argument can be treated as 'not caring what its value is'. Setting it to 0 or 1 does not affect the functionality, but it makes the semantics more clear, IMO. However, you've reminded me that the reassignment of .private in the second patch is problematic, and I will make a comment on that patch.