From nobody Fri Oct 3 15:37:00 2025 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 D40B633EAF4 for ; Fri, 29 Aug 2025 15:49:15 +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=1756482555; cv=none; b=IW6eUEAo2kYIsTOheWgqB6NX8tBQdvDNveAcX30lb4KhkkagdSEephTPT4/pZV2PwYUz0D8xH3HHs3qxD9yyjVRpQMR7GHiMNuxCbpXcHBw1zV610+2tP98tQdF7zZwRfCsYyPWKUVrRNr2Flwt+EOSfol6bpJW7jAYX7VEQRY8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756482555; c=relaxed/simple; bh=H42PRIJFhc68hczE5JFr8BulcuyrR8cWi/byZNSlUrw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ky+MNkhfKI1No9O95PwhHP4dcl09YgjujzPmNMnrPojP8i3YHJJIc+jTCP+FrFDVxm7O30U4Ss5jj3HRTG3ASwT1grMOGc77zgdWsm04Pazv1c3x/z1+A42WW7dGYD1ms9e+Tc1lLq3zz19Onn2VG6ts/yxPEBXWxE7ZX9A9sGY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AcVGpPnl; 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="AcVGpPnl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D073C4CEF6; Fri, 29 Aug 2025 15:49:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756482555; bh=H42PRIJFhc68hczE5JFr8BulcuyrR8cWi/byZNSlUrw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AcVGpPnlQT1jwi8qC6n4TM2FJ2My5t5SfEz9687CXaAWzknU5wiIjteY3u8GtlXx2 samFbf8UAxUsyqIh0Q1QOfA1zvJajbFOjTi8VNRQMxB0Za5RVZtSATYa7Z0tU+MWfr vvKop+2fRrFgEX5mff7dw6QQp7a0eaQZQ6cUU6k+4rEZInstCCOoyd3AZaQqWgryIB oMn2ZWkfv11old8eEHmnu4gJfUFc9DO7A/GKgshtQRTIRZbYTdiYyJY9en1/1mvRa2 slBNBSCVOw1t+n1g31piiGuhIsjTFxHqD4HWpiyMhP6PUORSTiq/2b8/vD9zbL1v1+ ghf5Klfdxd+Xg== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Ingo Molnar , Marco Crivellari , Michal Hocko , Peter Zijlstra , Tejun Heo , Thomas Gleixner , Vlastimil Babka , Waiman Long Subject: [PATCH 19/33] sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated() Date: Fri, 29 Aug 2025 17:48:00 +0200 Message-ID: <20250829154814.47015-20-frederic@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250829154814.47015-1-frederic@kernel.org> References: <20250829154814.47015-1-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_KERNEL_NOISE (of which HK_TYPE_TICK is only an alias) is always a superset of HK_TYPE_DOMAIN. Therefore if a CPU is not HK_TYPE_KERNEL_NOISE, it can't be HK_TYPE_DOMAIN either. Testing the latter is then enough. Simplify cpu_is_isolated() accordingly. Signed-off-by: Frederic Weisbecker --- 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 c02923ed4cbe..8d6d26d3fdf5 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -82,8 +82,7 @@ static inline void housekeeping_init(void) { } =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 2.51.0