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 61BC9C25B0E for ; Tue, 16 Aug 2022 12:03:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CCB0E6B0073; Tue, 16 Aug 2022 08:03:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C7B008D0001; Tue, 16 Aug 2022 08:03:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B69826B0078; Tue, 16 Aug 2022 08:03:43 -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 AA8EF6B0073 for ; Tue, 16 Aug 2022 08:03:43 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id D289D1A0804 for ; Tue, 16 Aug 2022 12:03:42 +0000 (UTC) X-FDA: 79805321484.22.C95970F Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf16.hostedemail.com (Postfix) with ESMTP id A7B251801C3 for ; Tue, 16 Aug 2022 12:03:40 +0000 (UTC) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4M6V8f3ps0zlVtw; Tue, 16 Aug 2022 20:00:34 +0800 (CST) Received: from dggpemm500001.china.huawei.com (7.185.36.107) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 16 Aug 2022 20:03:36 +0800 Received: from [10.174.177.243] (10.174.177.243) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 16 Aug 2022 20:03:36 +0800 Message-ID: <03f465ca-cf8e-bbd1-1083-099fd2ce026d@huawei.com> Date: Tue, 16 Aug 2022 20:03:35 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH RFC] mm, proc: add PcpFree to meminfo Content-Language: en-US To: Greg Kroah-Hartman CC: Andrew Morton , , , Liu Shixin , "Vlastimil Babka" , David Hildenbrand , Shakeel Butt References: <20220816084426.135528-1-wangkefeng.wang@huawei.com> <7bdc252f-15dd-8d92-9e08-1ba7dd8308ad@huawei.com> From: Kefeng Wang In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660651421; a=rsa-sha256; cv=none; b=NaMRBkln4g2XPLYNroIejPJtY1OHtZ0SHunFfxutt0A2VEZhFwwWNwVqM5MmsKrdI2IZaq ddBVe9ecfUH/4mcah8VyCNvOBZI+LAXUI85d00oHbT92HtrjnjXB78EaZPrTtjd8DMsrVx Fd3SBTNuYIwadoYPQXnPsVXJQpe/ysQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660651421; 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=iaUQggiPoJEtAGlrUKiFQ1DcEH/yfsMcxTNn4AjYeMo=; b=olb2Wm8dlfFke4KAwKRB96nc3zBwY05AQUI0UgW8yEcxd6KpP8OC0ZeCO6g2G3C83BKdiI j10pYlCHSWAVDz722mUPdNpVjw5ghDHbM4CQ7S/8Kth6tBE1j8RyO7HF0jwX58YBCuK5ul ADvQlWPT+tnTTTGlzoSuwyFb2vhLzUA= Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com X-Stat-Signature: s4xphg59td6pw9g6m3s8u1whk6u4twc4 X-Rspamd-Server: rspam09 X-Rspam-User: X-Rspamd-Queue-Id: A7B251801C3 X-HE-Tag: 1660651420-817093 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: On 2022/8/16 18:50, Greg Kroah-Hartman wrote: > On Tue, Aug 16, 2022 at 06:11:18PM +0800, Kefeng Wang wrote: >> On 2022/8/16 17:16, Greg Kroah-Hartman wrote: >>> On Tue, Aug 16, 2022 at 04:44:26PM +0800, Kefeng Wang wrote: >>>> From: Liu Shixin >>>> >>>> The page on pcplist could be used, but not counted into memory free or >>>> avaliable, and pcp_free is only showed by show_mem(). Since commit >>>> d8a759b57035 ("mm, page_alloc: double zone's batchsize"), there is a >>>> significant decrease in the display of free memory, with a large number >>>> of cpus and nodes, the number of pages in the percpu list can be very >>>> large, so it is better to let user to know the pcp count. >>>> >>>> Signed-off-by: Liu Shixin >>>> Signed-off-by: Kefeng Wang >>>> --- >>>> drivers/base/node.c | 14 +++++++++++++- >>>> fs/proc/meminfo.c | 9 +++++++++ >>>> 2 files changed, 22 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/base/node.c b/drivers/base/node.c >>>> index eb0f43784c2b..846864e45db6 100644 >>>> --- a/drivers/base/node.c >>>> +++ b/drivers/base/node.c >>>> @@ -375,6 +375,9 @@ static ssize_t node_read_meminfo(struct device *dev, >>>> struct sysinfo i; >>>> unsigned long sreclaimable, sunreclaimable; >>>> unsigned long swapcached = 0; >>>> + unsigned long free_pcp = 0; >>>> + struct zone *zone; >>>> + int cpu; >>>> si_meminfo_node(&i, nid); >>>> sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); >>>> @@ -382,9 +385,17 @@ static ssize_t node_read_meminfo(struct device *dev, >>>> #ifdef CONFIG_SWAP >>>> swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE); >>>> #endif >>>> + for_each_populated_zone(zone) { >>>> + if (zone_to_nid(zone) != nid) >>>> + continue; >>>> + for_each_online_cpu(cpu) >>>> + free_pcp += per_cpu_ptr(zone->per_cpu_pageset, cpu)->count; >>>> + } >>>> + >>>> len = sysfs_emit_at(buf, len, >>>> "Node %d MemTotal: %8lu kB\n" >>>> "Node %d MemFree: %8lu kB\n" >>>> + "Node %d PcpFree: %8lu kB\n" >>> First off, this sysfs file is a huge violation of the normal sysfs >>> rules, so I will not allow any new entries to be added. In fact, the >>> whole thing should just be removed and multiple files created in its >>> place. >> Hi Greg, do you mean to remove all /sys/devices/system/node/node*/meminfo, >> >> but this will beak ABI, is it acceptable? > I do not know, what tool relies on this file? Any userspace tool should > always be able to handle a sysfs file being removed, so you should > probably work with the tool authors to fix this up before removing it. https://github.com/numactl/numactl/blob/93867c59b0bb29470873a427dc7f06ebaf305221/numastat.c#L841 It seems numastat use this file, but there are maybe more tools, Cc'ed more mm experts to see more comments. > > thanks, > > gre gk-h > .