From mboxrd@z Thu Jan 1 00:00:00 1970 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 B9EA734D4F8; Wed, 5 Nov 2025 21:06:32 +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=1762376792; cv=none; b=DmA0EyEJuHphG/2oulKzXM1UNOlLhq44OAhsZjV33wqLoMp1pqSwdxBXd2KStYX9qtp+9PHtvCHVINdB/DoYYZIvTvt1BBaWgmwEL8U+52UXQhqj31X7OJoAxo+Bpq+SnPlCAZcXLiOldPrWcgGqxbcZNr1X+IMuVz0PzDtCB1w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762376792; c=relaxed/simple; bh=/4qlBV0o6wHpMCHv+PGJIH0/5p5VMnEM2VldkFFk/hA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kYH7QkPp/aFUYYXOLSFYiJ1U3/fHIsU9eNaPN3PuqUJLZD+Er5YywLcDX5xuEcErve/wwqPSii8HHv27fVXYrXUeB8qQ6b8a7cgVG+UXlTPXXn3DlIYFCT32lag96oRDZQpXApdi4cDG2lT/n4kJH46qe/VoykPko9qtl9dBBTY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WPMVl7Uv; 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="WPMVl7Uv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F01FC4CEF5; Wed, 5 Nov 2025 21:06:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762376792; bh=/4qlBV0o6wHpMCHv+PGJIH0/5p5VMnEM2VldkFFk/hA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WPMVl7UvVPMRPQhKg2eY/RDKFC1vZcXdD08AGo6Qq/JtNgo8kPbs91s/W0brc+V5w YScVpXtDvf96TJiGbbd3qjQihx33QG/l0iLxhIfzXvXPIv/C6GBZcpUsAOA5/LUs1n oaHLFsM5/jX9GEIO4TEpslLn6l3LkI9tBTlpdE50e1TEqi8N11MwGL1neMCwf138kP PlCf+SEUHcmKj9utkNTtcf5yDLRO3jFxTVgZtfFtvRXo7um6DMx6SJcAdriB6p90Nq yLFLyG0eKaF2fF2W+V+aALv1nrBq3tM7L8gCnFVt09OqEynVIJmKSvNgTQpXOuXEU1 1rE/ac7aW9QzQ== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Andrew Morton , Bjorn Helgaas , Catalin Marinas , 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 19/31] sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated() Date: Wed, 5 Nov 2025 22:03:35 +0100 Message-ID: <20251105210348.35256-20-frederic@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251105210348.35256-1-frederic@kernel.org> References: <20251105210348.35256-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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= 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) should always be a subset of HK_TYPE_DOMAIN. 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 --- 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/isolation.h index a127629adb32..a24acefacf9f 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) 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); } #endif /* _LINUX_SCHED_ISOLATION_H */ -- 2.51.0