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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 638FED12D4C for ; Wed, 3 Dec 2025 11:57:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B82C86B002A; Wed, 3 Dec 2025 06:57:20 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B5A436B0062; Wed, 3 Dec 2025 06:57:20 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A97E06B0088; Wed, 3 Dec 2025 06:57:20 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 98E336B002A for ; Wed, 3 Dec 2025 06:57:20 -0500 (EST) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 44E9351A5C for ; Wed, 3 Dec 2025 11:57:20 +0000 (UTC) X-FDA: 84178009440.06.99A6140 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) by imf25.hostedemail.com (Postfix) with ESMTP id 21567A0010 for ; Wed, 3 Dec 2025 11:57:16 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; spf=pass (imf25.hostedemail.com: domain of zhangguopeng@kylinos.cn designates 124.126.103.232 as permitted sender) smtp.mailfrom=zhangguopeng@kylinos.cn ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1764763038; 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: references; bh=ecpNQdXf41snpkLyfzcnnlY/e5tlxah9I5EKanLGJto=; b=kE5wuzdVb91nWkJWS1NRNPpfJSM4N5QD/UOKe8FsRMjJxlD4RjGgUDfCXpmd9vwKnupUts iohNS+ylTsCZBpvjAMJbewfP871+EUZDcATkOBXCRwGtm0k3Vtq3X/VYfsYyWD95Gnzip9 iscg1SLrvqHOMvJAJkaakQAIL8ViloI= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf25.hostedemail.com: domain of zhangguopeng@kylinos.cn designates 124.126.103.232 as permitted sender) smtp.mailfrom=zhangguopeng@kylinos.cn ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1764763038; a=rsa-sha256; cv=none; b=8iKWeF5X8VDqDcbJ1Gph659idy6+NjmGmheuJMYSuNd4H3Oxf5rUV6WD0QQKGM2Bx1FQNV /2YKPaScGJR8XNhtmoL2joS/30FCtf8FIr4M70rhHdrR1L5+Bvs+Gspu2EXNhCsLpt+yF7 o92ryryfvYpWs2DvIToFulkQ4tbLAqk= X-UUID: 2e8cd32ed03f11f0a38c85956e01ac42-20251203 X-CTIC-Tags: HR_CC_COUNT, HR_CC_DOMAIN_COUNT, HR_CC_NAME, HR_CC_NO_NAME, HR_CTE_8B HR_CTT_TXT, HR_DATE_H, HR_DATE_WKD, HR_DATE_ZONE, HR_FROM_NAME HR_SJ_DIGIT_LEN, HR_SJ_LANG, HR_SJ_LEN, HR_SJ_LETTER, HR_SJ_NOR_SYM HR_SJ_PHRASE, HR_SJ_PHRASE_LEN, HR_SJ_WS, HR_TO_COUNT, HR_TO_DOMAIN_COUNT HR_TO_NO_NAME, IP_TRUSTED, SRC_TRUSTED, DN_TRUSTED, SA_TRUSTED SA_EXISTED, SN_TRUSTED, SN_EXISTED, SPF_NOPASS, DKIM_NOPASS DMARC_NOPASS, CIE_GOOD, CIE_GOOD_SPF, GTI_FG_BS, GTI_C_CI GTI_FG_IT, GTI_RG_INFO, GTI_C_BU, AMN_T1, AMN_GOOD AMN_C_TI, ABX_MISS_RDNS X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.6,REQID:1f63d534-3ad7-4486-b2a6-722f38e3e2ba,IP:10,U RL:0,TC:0,Content:-5,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:0 X-CID-INFO: VERSION:1.3.6,REQID:1f63d534-3ad7-4486-b2a6-722f38e3e2ba,IP:10,URL :0,TC:0,Content:-5,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:a9d874c,CLOUDID:0ae958454a45d2f48fefce17dc0a4c5d,BulkI D:2512031957094HW49S03,BulkQuantity:0,Recheck:0,SF:17|19|38|66|78|102|127| 850|898,TC:nil,Content:0|15|50,EDM:-3,IP:-2,URL:99|1,File:nil,RT:nil,Bulk: nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,B RE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_FAS,TF_CID_SPAM_FSD,TF_CID_SPAM_ULS X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 2e8cd32ed03f11f0a38c85956e01ac42-20251203 X-User: zhangguopeng@kylinos.cn Received: from localhost.localdomain [(223.70.160.239)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1478738078; Wed, 03 Dec 2025 19:57:03 +0800 From: Guopeng Zhang To: tj@kernel.org, hannes@cmpxchg.org, mkoutny@suse.com, shuah@kernel.org, roman.gushchin@linux.dev, lance.yang@linux.dev, shakeel.butt@linux.dev Cc: muchun.song@linux.dev, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Guopeng Zhang Subject: [PATCH v5 0/3] selftests: cgroup: Enhance robustness with polling helpers Date: Wed, 3 Dec 2025 19:56:28 +0800 Message-Id: <20251203115631.947908-1-zhangguopeng@kylinos.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 21567A0010 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: m7r8n65c4otwdgr1qjm8zfpem36h95wi X-HE-Tag: 1764763036-828713 X-HE-Meta: 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 gMILSVfT F+pyukxTtO0mNHCElnzSdd4l5fT5O/0KI6eRja22SCq766V/O21yXvmtIyCJXIIEC8YxKx4ULN78CkNJwOeYgzwhb/Q== 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 all, This patch series introduces improvements to the cgroup selftests by adding a helper function to better handle asynchronous updates in cgroup statistics. These changes are especially useful for managing cgroup stats like memory.stat and cgroup.stat, which can be affected by delays (e.g., RCU callbacks and asynchronous rstat flushing). Patch 1/3 adds cg_read_key_long_poll(), a generic helper to poll a numeric key in a cgroup file until it reaches an expected value or a retry limit is hit. Patches 2/3 and 3/3 convert existing tests to use this helper, making them more robust on busy systems. v5: - Drop the "/* 3s total */" comment from MEMCG_SOCKSTAT_WAIT_RETRIES as suggested by Shakeel, so it does not become stale if the wait interval changes. - Elaborate in the commit message of patch 3/3 on the rationale behind the 8s timeout in test_kmem_dead_cgroups(), and add a comment next to KMEM_DEAD_WAIT_RETRIES explaining that it is a generous upper bound derived from stress testing and not tied to a specific kernel constant. - Add Reviewed-by: Shakeel Butt to this series. - Link to v4: https://lore.kernel.org/all/20251124123816.486164-1-zhangguopeng@kylinos.cn/ v4: - Patch 1/3: Add the cg_read_key_long_poll() helper to poll cgroup keys with retries and configurable intervals. - Patch 2/3: Update test_memcg_sock() to use cg_read_key_long_poll() for handling delayed "sock " counter updates in memory.stat. - Patch 3/3: Replace the sleep-and-retry logic in test_kmem_dead_cgroups() with cg_read_key_long_poll() for waiting on nr_dying_descendants. - Link to v3: https://lore.kernel.org/all/p655qedqjaakrnqpytc6dltejfluxo6jrffcltfz2ivonmk6lb@bxf5xlgo4iw2/ v3: - Move MEMCG_SOCKSTAT_WAIT_* defines after the #include block as suggested. - Link to v2: https://lore.kernel.org/all/5ad2b75f-748a-4e93-8d11-63295bda0cbf@linux.dev/ v2: - Clarify the rationale for the 3s timeout and mention the periodic rstat flush interval (FLUSH_TIME = 2 * HZ) in the comment. - Replace hardcoded retry count and wait interval with macros to avoid magic numbers and make the timeout calculation explicit. - Link to v1: https://lore.kernel.org/all/20251119122758.85610-1-ioworker0@gmail.com/ Thanks to Michal Koutný for the suggestion, and to Lance Yang and Shakeel Butt for their reviews and feedback. Guopeng Zhang (3): selftests: cgroup: Add cg_read_key_long_poll() to poll a cgroup key with retries selftests: cgroup: make test_memcg_sock robust against delayed sock stats selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on nr_dying_descendants .../selftests/cgroup/lib/cgroup_util.c | 21 ++++++++++++ .../cgroup/lib/include/cgroup_util.h | 5 +++ tools/testing/selftests/cgroup/test_kmem.c | 33 +++++++++---------- .../selftests/cgroup/test_memcontrol.c | 20 ++++++++++- 4 files changed, 60 insertions(+), 19 deletions(-) -- 2.25.1