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 7F56EC369D3 for ; Sun, 20 Apr 2025 21:48:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 90F2E6B0005; Sun, 20 Apr 2025 17:48:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BDAB6B0006; Sun, 20 Apr 2025 17:48:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 75ED66B0007; Sun, 20 Apr 2025 17:48:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 53C566B0005 for ; Sun, 20 Apr 2025 17:48:22 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id E5A07C096A for ; Sun, 20 Apr 2025 21:48:22 +0000 (UTC) X-FDA: 83355761244.24.2D90C5E Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf12.hostedemail.com (Postfix) with ESMTP id 8C4BB40005 for ; Sun, 20 Apr 2025 21:48:20 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=KzmQA7rV; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf12.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1745185700; a=rsa-sha256; cv=none; b=n1JmGCT8/38JxiwsQxJEXfaH/N9OcHCwlzbavF5WJoNvA8RsQiqPQJpkezuo1FqDNIHRMy NqeHzmrXb09D4P7WlxQTE7y39zwVaz8XKoFPufbxSC2I0fqpUeIncT05dUvTl+1qMiJV8I Brm0AKTFW0rG+6cROpRvQMbFp7YvxUU= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=KzmQA7rV; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf12.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1745185700; 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:dkim-signature; bh=GOUfeRWcjMIh7HWgzJ0PWrB/E+2a4XRZ58CSESwgEfQ=; b=uMb3t+FeBv9xjPBcwKIuslK3TKlWfHgfHG4nTSKCL/wEoBiH+kfoL0A8PfyCJj23MDBYrQ gojM+/bFH4ec2xgZ3XEUax4duwsDRQ08dV8BDEczWzSQLAyLcjUYGUyrCeVWXfQSBb7Ott 1Jf5CTZMUelQl+ki5dl5pLwJfFs2dIQ= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1745185700; h=from:from: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=GOUfeRWcjMIh7HWgzJ0PWrB/E+2a4XRZ58CSESwgEfQ=; b=KzmQA7rVzLpXT6SxTkoRiFWciCgYynkTdAE/g10vd1JyQiA3k/fTlAaTkJQnaxBdML41TK 18XxBQdC2o8su0+VV8P8rdCHCuTRqlylcss8AT5HpAUOCcs3swS80ZJGpq8VikHHBKWpkF cFMZ5DKjZNxlpYVJFRmrURvF9PHQc40= Received: from mail-qv1-f71.google.com (mail-qv1-f71.google.com [209.85.219.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-76-7HNlsFr8M3GTMycWncpmIA-1; Sun, 20 Apr 2025 17:48:18 -0400 X-MC-Unique: 7HNlsFr8M3GTMycWncpmIA-1 X-Mimecast-MFC-AGG-ID: 7HNlsFr8M3GTMycWncpmIA_1745185698 Received: by mail-qv1-f71.google.com with SMTP id 6a1803df08f44-6e91d8a7165so60564576d6.0 for ; Sun, 20 Apr 2025 14:48:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1745185698; x=1745790498; h=content-transfer-encoding:in-reply-to:content-language:references :cc:to:subject:user-agent:mime-version:date:message-id:from :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=GOUfeRWcjMIh7HWgzJ0PWrB/E+2a4XRZ58CSESwgEfQ=; b=bkghclPRXC5EDOft9/OWGXRvlWz+ATQU42rvuBanL7xTpsaiooi0q98ebtbUXZKA86 W6w4CgKVnxsOvY2q7elgPEPHlYfdZrZ1okX8GWbELeaZljvARU6z3Ze5yO8JRH+uCeK3 bhW8QJ0B0KoS88kJTFk/7Mgo2Ib261JgTCJlinHkXDMQMlg3clHEUKUP/rRfM2+UD1xA IeSPv27B1XNPYQRYXjaLvrrZSZEV3jBK+iOha4Xy733gTAj3XgJ+04FhzUeMEOi3edFW JA3r7abFgKJRGcwPZsDjUQBIIOj3+bYASevo03FUSnL6SZE957yx+vHTukwZ/SaMU5tK MT1w== X-Forwarded-Encrypted: i=1; AJvYcCUMlOw/Dy7eYddbnRYsGV0ZldbO6J9Bv4QlKFv8vB3AwGjsd5lMd/nZWBz2vD2rCiR71Kj5pkrqXA==@kvack.org X-Gm-Message-State: AOJu0Yzab1HBScpH4eR2PSe3l7EX9f7+M/eT9Ev8ahoy3pOTqxb6ldO9 nUXXxZPQpInSma/sae+qSXo+CzUDTzarhoe/Mk5pXTiQBiE3j5obqFAY6PE9nv1dkObkXhs2h10 oCyw5g+kMRbpqe10vHzVfTrlZBV4IAr99E/lYTdhLx3myiLyr X-Gm-Gg: ASbGncuv61J4tQm7xvFw7FLhY/LCujResoEMrxa4e3fA3jdghU1p/ePkLbhrasq4gmU DE4zX6Zf+UZf2p7nyqTUrxfsKE2sd40/WdJoUfh8ss0x2s4bEutjAgLL+k0PkIenGmF21MWIYif aU7Fj2AMaavr8vfdhjLK9VfPJ8k/KLdmVmxuPKkry2ZuafZ0xqsq02C3sRBSQDJo4wA3cdrqnK4 S7ZkC2o3phUTQdsjVp8OnCgWmBToiM8bsyQdi7UZ3Koj5duV3Q/pAS7iWXnZS7CCpR7IWJ/QpUl jyY4EsC0JIxKjMzZ7nKJGztbNk0UkY2aAu7xBofyOTafsTmJlw== X-Received: by 2002:a05:6214:20ee:b0:6f0:e2e1:50b4 with SMTP id 6a1803df08f44-6f2c4665552mr155639766d6.35.1745185698071; Sun, 20 Apr 2025 14:48:18 -0700 (PDT) X-Google-Smtp-Source: AGHT+IE1rjz0rbTdMsGxlXep21QS1BL8dfWYnSrJCLKXWkQdNHadHwWjUHhvmnzBn0KbSPKMCrPC5Q== X-Received: by 2002:a05:6214:20ee:b0:6f0:e2e1:50b4 with SMTP id 6a1803df08f44-6f2c4665552mr155639546d6.35.1745185697701; Sun, 20 Apr 2025 14:48:17 -0700 (PDT) Received: from [192.168.130.170] (67-212-218-66.static.pfnllc.net. [67.212.218.66]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-6f2c2b0e2b2sm36456396d6.28.2025.04.20.14.48.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 20 Apr 2025 14:48:17 -0700 (PDT) From: Waiman Long X-Google-Original-From: Waiman Long Message-ID: <0033f39f-ff47-4645-9b1e-f19ff39233e7@redhat.com> Date: Sun, 20 Apr 2025 17:48:15 -0400 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/2] selftests: memcg: Allow low event with no memory.low and memory_recursiveprot on To: =?UTF-8?Q?Michal_Koutn=C3=BD?= Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , Tejun Heo , Shuah Khan , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org References: <20250415210415.13414-1-longman@redhat.com> <20250415210415.13414-2-longman@redhat.com> In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: QDeJ51TKOvuM759Y6AxGZuirOcsNOcqJ-T3kJ76RmyI_1745185698 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: 8C4BB40005 X-Rspamd-Server: rspam04 X-Stat-Signature: fo9my1x8xnin7wf7nhxjt5f33mwaw8e6 X-HE-Tag: 1745185700-986374 X-HE-Meta: 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 wDQ2Szvw 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 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: On 4/16/25 5:25 AM, Michal Koutný wrote: > On Tue, Apr 15, 2025 at 05:04:14PM -0400, Waiman Long wrote: >> + /* >> + * Child 2 has memory.low=0, but some low protection is still being >> + * distributed down from its parent with memory.low=50M if cgroup2 >> + * memory_recursiveprot mount option is enabled. So the low event >> + * count will be non-zero in this case. > I say: Child 2 should have zero effective low value in this test case. > Johannes says (IIUC): One cannot argue whether there is or isn't > effective low for Child 2, it depends on siblings. > (I also say that low events should only be counted for nominal low > breaches but that's not so important here.) > > But together this means no value of memory.events:low is valid or > invalid in this testcase. Hence I suggested ignoring Child 2's value in > checks. I understand your point of view. What I want to do is to document the expected behavior and I don't see any example of ignoring a metric for a particular child in the test. In this particular test, I did see an elow of 17 for child 2. > >> + */ >> for (i = 0; i < ARRAY_SIZE(children); i++) { >> - int no_low_events_index = 1; >> + int no_low_events_index = has_recursiveprot ? 2 : 1; >> long low, oom; >> >> oom = cg_read_key_long(children[i], "memory.events", "oom "); > But this is not what I Suggested-by: [1] I was referring to the suggestion that the setting of memory_recursiveprot mount option has a material impact of the child 2 test result. Roman probably didn't have memory_recursiveprot set when developing this selftest. I can take out the Suggested-by tag. Cheers, Longman > > Michal > > [1] https://lore.kernel.org/r/awgbdn6gwnj4kfaezsorvopgsdyoty3yahdeanqvoxstz2w2ke@xc3sv43elkz5