From patchwork Fri Feb 3 23:24:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Frederic Weisbecker X-Patchwork-Id: 52711 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:eb09:0:0:0:0:0 with SMTP id s9csp1109647wrn; Fri, 3 Feb 2023 15:33:10 -0800 (PST) X-Google-Smtp-Source: AK7set8aVcnFGI4X7Vz3BfkJhBOG1hRGnIaSj2SSUAVz9Ws5rTc74/HrTwqkOcVOpQj2A32OSOfz X-Received: by 2002:a05:6a21:6d87:b0:be:b106:3191 with SMTP id wl7-20020a056a216d8700b000beb1063191mr8303243pzb.49.1675467190130; Fri, 03 Feb 2023 15:33:10 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1675467190; cv=none; d=google.com; s=arc-20160816; b=iWHr0L/1UuSua+fK/d8YQwlQdiiZFR0O7pSxRBrarqKVsbB7FOnWLtxK++q5TNjO9u MLPsoPLl22IbPF07j9pM+cv8GHckIIVcqzWoamiv25q2DX2YmxG4yeN2ZMjpTcLH1Ile u6R9MSdMiq9k9WAdMJ3kmmwFKgaFrEIVH33DHrGYH4C+2K+xprawb/gS7PsXQPy+SxHp 1lMTOFpwc2DcvmuoZYtV8zOpI1sHinPpsIfGYqmeq+LGqctjdHz01QmSQBg38dKY4rzj XKOvKdnzg4du3CsJbAVOYcMhtx3HCLi9XINM/GrDVKNmDCEAE4QYsjbMfaVXGeZMUXjj athA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=dqerDqdAeP2Tp7uc6qYn/twDFlW0xEaI/tXSRkFDxsU=; b=KzWqGuSLYij2w+VdRzllbNNSEgHyHdffJ4+gAEy/JgL/CszngYv+N/wAJVqABdjc99 0RbAQpcDPHbg94m3X+cIEWDI8V8bQVZhxba2v/o0ijWTb87mzbNp6wA6exPqxiKmIo1M fgCHkHTErSP3Y9FJk/l18A/egFU4og/tdKHrrwjXA4NTb2QJmuEEJnKPonvhxaQ8qd1N cK7JP+ndckTHD3Zdq1hcptt/g+TreM2Yohr9Z5+IaAn0LJbA4FtxTRTCqqBh+BchiOjm 9dreVPLYILXj10Qw9/AQq4gTc2MxAQAjF5Ofh9beFE8qlmJvhCCoFttkgXyqIWJ42zdK WjSA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=BuCrVsu7; 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=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id k65-20020a633d44000000b004f1956b50f6si4179084pga.466.2023.02.03.15.32.57; Fri, 03 Feb 2023 15:33:10 -0800 (PST) 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=@kernel.org header.s=k20201202 header.b=BuCrVsu7; 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=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233199AbjBCXYc (ORCPT + 99 others); Fri, 3 Feb 2023 18:24:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232667AbjBCXY0 (ORCPT ); Fri, 3 Feb 2023 18:24:26 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F34CEA6BBE; Fri, 3 Feb 2023 15:24:25 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AEC09B82C3F; Fri, 3 Feb 2023 23:24:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A79AC4339B; Fri, 3 Feb 2023 23:24:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675466663; bh=p1w/s0O5n3VSeOMpM1vDKAz+K6RPGrIp6QpaiUCAbUc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BuCrVsu7EsqwcuHwg7AUSbKZd6w6kULIQHrvnJZdUFECtU5/XPaHlkkcxjMPEhLga KVzT7ESVrOE/BZJQFfSitLQe2lUzquK9cVIp2Iw3xIk+Iozoq0lPn/0/CP26maBNXy kJnaR8PUUKkTPEFx3+exk8co1JIx29PdVQ8zDWpvfr1ct+VQB2f3sNJJSC6tHoXyz7 8u1AQd75R/OsWTxVL8XsPr0NtOj6elD8dcH+8S2k8+fk6jFIliCOej9sZNkuh0C6sE ds9hl+PCcLXgThtlugAUMHXnxGzGqkv4iUizOyXVr0YqhP3pgTHk/zCI9g5lYKWSRU iewsp3xAyNdkA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Roman Gushchin , Michal Hocko , Marcelo Tosatti , Leonardo , Johannes Weiner , Shakeel Butt , Muchun Song , Andrew Morton , Peter Zijlstra , Thomas Gleixner , cgroups@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 2/2] sched/isolation: Add cpu_is_isolated() API Date: Sat, 4 Feb 2023 00:24:09 +0100 Message-Id: <20230203232409.163847-3-frederic@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230203232409.163847-1-frederic@kernel.org> References: <20230203232409.163847-1-frederic@kernel.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS autolearn=ham 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?1756854684222389705?= X-GMAIL-MSGID: =?utf-8?q?1756854684222389705?= Provide this new API to check if a CPU has been isolated either through isolcpus= or nohz_full= kernel parameter. It aims at avoiding kernel load deemed to be safely spared on CPUs running sensitive workload that can't bear any disturbance, such as pcp cache draining. Suggested-by: Michal Hocko Signed-off-by: Frederic Weisbecker --- include/linux/sched/isolation.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index b645cc81fe01..088672f08469 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -53,4 +53,10 @@ static inline bool housekeeping_cpu(int cpu, enum hk_type type) return true; } +static inline bool cpu_is_isolated(int cpu) +{ + return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN) || + !housekeeping_test_cpu(cpu, HK_TYPE_KERNEL_NOISE); +} + #endif /* _LINUX_SCHED_ISOLATION_H */