From patchwork Tue Mar 28 06:16:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 75843 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2004558vqo; Mon, 27 Mar 2023 23:22:08 -0700 (PDT) X-Google-Smtp-Source: AKy350YaK+kN2+yyF7evJzcOhpjtaSNp3POUBIy8ikI/lFNCiae3bxur4t9Xj4RybTCnZ+aK0027 X-Received: by 2002:aa7:dbcb:0:b0:501:fd71:7e18 with SMTP id v11-20020aa7dbcb000000b00501fd717e18mr15163123edt.2.1679984528121; Mon, 27 Mar 2023 23:22:08 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1679984528; cv=none; d=google.com; s=arc-20160816; b=KI8I5s58zlWQKO+B39IXFzINgC2mHXBrSnLrtdU31bArF8U526zZGEqg94ziAZI0Uw eHA0tlHChScqhvIAA+1MufI+TkXElQ0d5UiJn4MLgg/maKOTIm4Xyk40OynHNOuJzVGh MLob0z7cfnhBaQyp9pjrWIALdjL57TDuRMNgKI1Z4RQ+hY0tpFDyTP7isw70vnJSzPjM xsoZQTZulJdabacMgowm77FecGCMfZQd8iVzk2amYkEXTchk6ftNsexHVHXbWurbizZD HFiBBtuAOZYeOAHtG29xQ4g+EECfTZg8evlcZmtD/3Vf442b3HkQtoUeAGrYo27rXD3V 5tcQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:dkim-signature; bh=+vNiceMoZ2PdzrNG/xVeRzEo7O+ovCZNHcQMp7VClk4=; b=hZeFVm1TlFsRnVdJPuo8oeZU01IWal58g9MzhzTxf8NUmsZIsptjTXb/GD4izVXj82 umRPR35+T9WN0pFQODEwMMh4y/Lk+eZM8RmoRacwIydihwq8DKQWxxZhi2+23ucSz+jy mvEfAlPOuUrqNK09B9mM1hNwN3Z6UZMTe1yHGMjeOucpJ3eLApTsEhbCV07HJi0XPWeZ xo96LRLAtJAOVZ+L4Ymrlen7sWBIdqO0Zn8gOovzsrRziWaQKJIUwxIsy0zy1YhHQD4r l+J16qEDveDQR7AnFKNR/4Q+SYoELE0A8gSetQbgKEC7bRmCsRaTmFphRmNvBNXlCkRD bf0Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20210112 header.b=FtVms547; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id z5-20020aa7c645000000b004fc19199fd6si26956509edr.143.2023.03.27.23.21.44; Mon, 27 Mar 2023 23:22:08 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20210112 header.b=FtVms547; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232625AbjC1GRe (ORCPT + 99 others); Tue, 28 Mar 2023 02:17:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34448 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232502AbjC1GRF (ORCPT ); Tue, 28 Mar 2023 02:17:05 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0CC835B6 for ; Mon, 27 Mar 2023 23:16:49 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id q15-20020a63d60f000000b00502e1c551aaso3002136pgg.21 for ; Mon, 27 Mar 2023 23:16:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1679984209; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=+vNiceMoZ2PdzrNG/xVeRzEo7O+ovCZNHcQMp7VClk4=; b=FtVms547YGVdf9XAqjguoo0WST2Bomcq4pMeCW3qlg0ksZV5swPoVz0GmrxFu8vfrh HBzgJptVGGKy7geKpBPvC2PsWo0HmjT2F27i9dbdVA6zCF4EYemeZRNrh89DbSPqLObX h82tbSvZ/WCeLjLtii1Meb+k3BLVneGl+TdsHqmfTXT/vAFZIC+/S3Aw9k3ElSrpUy7X 9xgxQRUTlE19S9rQfATi59HRnf65TEpEpviTmJbLID2U9/qvSayVfcGFQGEl03zvUEu5 uDhGnK3XWBy1kJngfOB04Odcd1UeEO5WA33WjKyVDhleLQy8k50zMQSY0RXklX82o1Jn CmFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679984209; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=+vNiceMoZ2PdzrNG/xVeRzEo7O+ovCZNHcQMp7VClk4=; b=kK8uZbg+oTUmTeBmvVzUVdy6zltfhI3DEFToy5S6M/JHn5FIpxHBwFt1upFEvHfsIT jshcRb5WjddkuxwlmFt8nKatoq1GqrBgxzeQm7k9seG+Il1wjvNL9OPNrHiy1ecmOu37 eNgK8XHO+cDCHwyY7K8sK4ST6eo5JsKGviOe7ygz3oPAdiO7xSimxXjH/O7iAt9Ldcaq 7VCtGNrSMjGsTsooUcN2OC96pDb6VSjWOBNNvAcCxdLS5JURdcLTE4vooYkLhYLBNdSL UpFGvu7JRQhNv2KcQcvnV5DZSeeqCJvwrKsj0sBzEpNKXdb0tUbhK9g26Vrgg5npWZsq Tkiw== X-Gm-Message-State: AAQBX9e8SZ8OHEX4bVAYpG/M7glCdUkbh0YI/c9MfUYyQs5L+AWkvQeQ lZp11N31zOqDrCMdqfZKnoirl8GzxYYQ/JaP X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a05:6a00:1a46:b0:625:c7de:48c1 with SMTP id h6-20020a056a001a4600b00625c7de48c1mr7269994pfv.4.1679984209151; Mon, 27 Mar 2023 23:16:49 -0700 (PDT) Date: Tue, 28 Mar 2023 06:16:33 +0000 In-Reply-To: <20230328061638.203420-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230328061638.203420-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.348.gf938b09366-goog Message-ID: <20230328061638.203420-5-yosryahmed@google.com> Subject: [PATCH v1 4/9] cgroup: rstat: add WARN_ON_ONCE() if flushing outside task context From: Yosry Ahmed To: Tejun Heo , Josef Bacik , Jens Axboe , Zefan Li , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , " =?utf-8?q?Michal_Koutn=C3=BD?= " Cc: Vasily Averin , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, Yosry Ahmed X-Spam-Status: No, score=-7.7 required=5.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1761591456371677306?= X-GMAIL-MSGID: =?utf-8?q?1761591456371677306?= rstat flushing is too expensive to perform in irq context. The previous patch removed the only context that may invoke an rstat flush from irq context, add a WARN_ON_ONCE() to detect future violations, or those that we are not aware of. Signed-off-by: Yosry Ahmed Reviewed-by: Shakeel Butt --- kernel/cgroup/rstat.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index d3252b0416b6..c2571939139f 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -176,6 +176,8 @@ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep) { int cpu; + /* rstat flushing is too expensive for irq context */ + WARN_ON_ONCE(!in_task()); lockdep_assert_held(&cgroup_rstat_lock); for_each_possible_cpu(cpu) {