From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.148 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793883839; b=2xtJxLMJ7MmQqGu1diqY9wMOIto9VECrJ+mluhIR+T89hc5BWOE9ocpsTYba/e2UtGq0 CPTuD9Tkf6sEKbMHxbhJzqTR7q5I82j0UcDX4NVQgCwaOY8XRQ0eKWvmheEEU4nqIK3S4 eAIREnQ7oBPh8ra2M8t1K2fv8fameicI84bHVjlG66eEnXiWrRhv/Qtgq0dZBD8WsHc4V n3X7dgAm78pp0+ypfHw0eeg4jfVmcL0e+pICYQzHfcJl4A20OQX0CE1Um72hbVRzRSOhF 0DOEDd9QKuyjVPEfd99M+5nSgNiZ9cMy3Py4kzI1LQLEQK5g1/et6OCO4ySGWUEeptg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793883839; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=Ow3hYsokloz6dGsTIFWuZiX4Z7MaaZQBVMCHUvEpQcs=; b=nF3+fjCG2nXxPZP9OiF0RPKbn5BWHbqkfMPMu1Ew+rv9/GeReuo0pGQQwGqmpertQ/qu 1fsWsVVNzWoeywjthctxd4M7GAU+v698VV1ojSVDB9rAKtV706c0KbRLwE66R6F7XWNQa 6/geKoGv6jSNFowMxfz9WS96OVPJq07/n3j6T76u4AJlBqmmpVtg7TBBN5jDLlRCXvRtd cU1wjyZc64e6+KdmpdWfFAWJa3gRxyyuBbbgv3RSyiub4WfT5UecTTKW8U1x/CbwHxauo vetslTywC/o058hV4QcR9G2qoL1/XuHEchrAIlnvrzMEjLO4x3/P8pkJWry+AjbPkUQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=LjU3DOYK; arc=none smtp.remote-ip=91.218.175.148 Received: from mta0.migadu.com (out-148.mta0.migadu.com [91.218.175.148]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2FE3C606A326 for ; Thu, 5 Nov 2026 13:03:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 2FE3C606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=LjU3DOYK X-Envelope-To: cgroups@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=yjmLzbvOob+0DqNmhGg+eJW8ryTKkW21nhtP6VxEd2c=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793883837; v=1; x=1794488637; b=LjU3DOYKC0o+GDgMmYz2VEdORFRrDkDHtGQ5qKHrKI1imh0QpPPrX6T6cntRUCPA6CdSDaEt +nZ+2eNKmaObL+p/SOlYM9LEJdf6kCj5KjTARWWkvmmfBqzrdmcPnLsSXMOaa/MyS/NSJENSvmD PUao0lD4ZTBJxqP3mDJT4Eao= X-Envelope-To: cgroups@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id aadead35cd8216c4; Thu, 05 Nov 2026 13:03:57 +0000 X-Mizu-Trace-ID: aadead35cd8216c4 X-Migadu-Flow: FLOW_OUT From: Guopeng Zhang To: longman@redhat.com, tj@kernel.org, ridong.chen@linux.dev Cc: guopeng.zhang@linux.dev, hannes@cmpxchg.org, mkoutny@suse.com, shuah@kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Guopeng Zhang Subject: [PATCH v2 0/3] cgroup/cpuset: Keep the top scheduling domain populated Date: Thu, 5 Nov 2026 21:03:41 +0800 Message-ID: <20261105130344.664336-1-guopeng.zhang@linux.dev> X-Mailer: git-send-email 2.43.0 X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Guopeng Zhang Boot-isolated CPUs stay in top_cpuset.effective_cpus, but are excluded from its scheduling domain. Allocating all boot domain housekeeping CPUs to partitions can therefore leave the top scheduling domain empty even though effective_cpus is nonempty, leading to warnings and an OOPS in build_perf_domains(). CPU hotplug can reach the same state. The patches are ordered as follows: 1. Check local and remote partition creation and CPU mask updates. 2. Check the hotplug paths without crediting CPUs that remain allocated to child partitions, and invalidate local or remote partitions as needed to restore an active boot domain housekeeping CPU. 3. Release an isolated child's CPUs when its parent is already invalid. Changes since v1: Rework the fix following Ridong's suggestion and add test cases. Add patch 2 for CPU hotplug and patch 3 for isolated CPU cleanup when the parent partition becomes invalid. v1: https://lore.kernel.org/all/20261104071600.474587-1-guopeng.zhang@linux.dev/ Guopeng Zhang (3): cgroup/cpuset: Reject updates that empty the top sched domain cgroup/cpuset: Keep the top sched domain non-empty on CPU hotplug cgroup/cpuset: Release isolated CPUs when the parent is invalid kernel/cgroup/cpuset.c | 59 ++++++++++++++++++- .../selftests/cgroup/test_cpuset_prs.sh | 55 +++++++++++++++++ 2 files changed, 111 insertions(+), 3 deletions(-) -- 2.43.0