From nobody Sat Feb 7 21:14:35 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2280C30F53E; Sun, 25 Jan 2026 22:48:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769381331; cv=none; b=E6J45m3C+6crnE8kU+GNT2RxecELB5mAeF5Nk3q2jSZ414a9I3Qbxwh+UTtT0Q+vun3Zvezt7pZdbBh/IXcAdR6LinVvP+O5Q38j5iufz/OOJ2QQymm3NFZDWoaIi3e3AWY/+kduk4ypEOck7o2IeZ6ySlPje5UY/HPLguHVwk8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769381331; c=relaxed/simple; bh=97q8vd09m+nJzodwGZsfdaDvcrqWHJSN7XyvoB2eWkE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VUATO/j/FXIZS6TUPsdFsHCCi3M471euwGQARcsB1lxyoUPbH5P6wiwk+pddvdSwCKPp8N6pCjyqZslyqGCXFT9Eqno6Ik001glgKe0S56akImLZcmOT+8nh+MMWZzlLmJcZz2Zql6GzwuEJdpoRVikL8OVrWNqQpX50NpGrmHs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iWzxMvwP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iWzxMvwP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53A44C2BC87; Sun, 25 Jan 2026 22:48:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769381331; bh=97q8vd09m+nJzodwGZsfdaDvcrqWHJSN7XyvoB2eWkE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iWzxMvwPS1SK8km3fkUM3KgJIRikD7FClNxi0QRWA5JrZfgoAG74mwdpsj77nQw7W pS+cblqrXwGcEsssKQkPukfkT8uGiTsqgSu+22HsHe4DVh85FGH00kq2D7pa1DxYEH 3KYGi+/nHiOvpcakIiLZcJpmeXLgnPPfK6QTjgIuYcRznlaAEkzvcG1T9xHmLiE6gW VhoV0F6r3pRrttIteAXMq8adrmOLmzsmN152Dd46Ig++lgee4RGIOmvFVu6kyCJL7j sthW3q5UKNvsici9viFfBwMpf++h32gi9Utw5uqLE3nA9hfyEqCrVZLa3kB3gzWwBh u3g2L4UmLlXyg== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Andrew Morton , Bjorn Helgaas , Catalin Marinas , Chen Ridong , Danilo Krummrich , "David S . Miller" , Eric Dumazet , Gabriele Monaco , Greg Kroah-Hartman , Ingo Molnar , Jakub Kicinski , Jens Axboe , Johannes Weiner , Lai Jiangshan , Marco Crivellari , Michal Hocko , Muchun Song , Paolo Abeni , Peter Zijlstra , Phil Auld , "Rafael J . Wysocki" , Roman Gushchin , Shakeel Butt , Simon Horman , Tejun Heo , Thomas Gleixner , Vlastimil Babka , Waiman Long , Will Deacon , cgroups@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 22/33] sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated() Date: Sun, 25 Jan 2026 23:45:29 +0100 Message-ID: <20260125224541.50226-23-frederic@kernel.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20260125224541.50226-1-frederic@kernel.org> References: <20260125224541.50226-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" It doesn't make sense to use nohz_full without also isolating the related CPUs from the domain topology, either through the use of isolcpus=3D or cpuset isolated partitions. And now HK_TYPE_DOMAIN includes all kinds of domain isolated CPUs. This means that HK_TYPE_DOMAIN should always be a subset of HK_TYPE_KERNEL_NOISE (of which HK_TYPE_TICK is only an alias). Therefore if a CPU is not HK_TYPE_DOMAIN, it shouldn't be HK_TYPE_KERNEL_NOISE either. Testing the former is then enough. Simplify cpu_is_isolated() accordingly. Signed-off-by: Frederic Weisbecker Acked-by: Waiman Long --- include/linux/sched/isolation.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolatio= n.h index d0fb0f647318..dc3975ff1b2e 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -82,8 +82,7 @@ static inline bool housekeeping_cpu(int cpu, enum hk_type= type) =20 static inline bool cpu_is_isolated(int cpu) { - return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN) || - !housekeeping_test_cpu(cpu, HK_TYPE_TICK); + return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN); } =20 #endif /* _LINUX_SCHED_ISOLATION_H */ --=20 2.51.1