From nobody Fri Oct 3 01:57:08 2025 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 420E4261388; Tue, 9 Sep 2025 03:48:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757389685; cv=none; b=byrMzGVvq/oQY87kXjTPNa++ZcAAnaArPwl7hv6JK3BFObl4fwgovDdS/TCeB1WYOXLb/HTz6/1ZVlbjafHtsK3Y10rdoWmR0UIJKTYfRwXDwuOJmF1MM/ZXJLRm30z1+YsZgVsa3BJ2G5hAWADig+TwlsTkjRM3vr07IL4qifo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757389685; c=relaxed/simple; bh=7SHtBGmz0A9KCaRR3aS1AivxF4yyYSLlFcDGkD+MNeY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Igk55/Udh4+1AmxtM1qOCzhte+/XyZG2Dru2BvU6nUaamBnVFaywCSZravTkyDLTjC2IlIviTS4TJcLA2PgmCIy3sway6EZUNnV5gwRLgatkHw/y8FXHrRV5Pk36wtY9cl2DsFBX1+EuRzLHBdBobici3aFfmxeqB/97fu9JVqA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4cLVCK2WLszYQv56; Tue, 9 Sep 2025 11:47:57 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id D2DC51A1040; Tue, 9 Sep 2025 11:47:55 +0800 (CST) Received: from hulk-vt.huawei.com (unknown [10.67.174.121]) by APP1 (Coremail) with SMTP id cCh0CgAnM3lOo79oBVdmBw--.63383S8; Tue, 09 Sep 2025 11:47:55 +0800 (CST) From: Chen Ridong To: longman@redhat.com, tj@kernel.org, hannes@cmpxchg.org, mkoutny@suse.com Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, lujialin4@huawei.com, chenridong@huawei.com Subject: [PATCH -next RFC -v2 06/11] cpuset: introduce cpus_excl_conflict and mems_excl_conflict helpers Date: Tue, 9 Sep 2025 03:32:28 +0000 Message-Id: <20250909033233.2731579-7-chenridong@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250909033233.2731579-1-chenridong@huaweicloud.com> References: <20250909033233.2731579-1-chenridong@huaweicloud.com> 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 X-CM-TRANSID: cCh0CgAnM3lOo79oBVdmBw--.63383S8 X-Coremail-Antispam: 1UD129KBjvJXoWxWFy5Aw47urW7CFyftw17trb_yoWrGw15pF WUGrWakayjgr13Gw43Gwn7WrsYgw40qFnFkw15Jr1fAry7GF12vwn5XwnxAFy5Jrs5G345 tF9xtw4S9F98J37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBYb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lc7CjxVAaw2AFwI0_JF0_Jw1l42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2I x0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI42IY6xAI w20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x 0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU1l_M7UUUUU== X-CM-SenderInfo: hfkh02xlgr0w46kxt4xhlfz01xgou0bp/ Content-Type: text/plain; charset="utf-8" From: Chen Ridong This patch adds cpus_excl_conflict() and mems_excl_conflict() helper functions to improve code readability and maintainability. The exclusive conflict checking follows these rules: 1. If either cpuset has the 'exclusive' flag set, their user_xcpus must not have any overlap. 2. If both cpusets are non-exclusive, their 'cpuset.cpus.exclusive' values must not intersect. 3. The 'cpuset.cpus' of one cpuset must not form a subset of another cpuset's 'cpuset.cpus.exclusive'. Signed-off-by: Chen Ridong --- kernel/cgroup/cpuset.c | 74 +++++++++++++++++++++++++----------------- 1 file changed, 44 insertions(+), 30 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 55674a5ad2f9..389dfd5be6c8 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -582,6 +582,47 @@ static inline bool cpusets_are_exclusive(struct cpuset= *cs1, struct cpuset *cs2) return true; } =20 +/** + * cpus_excl_conflict - Check if two cpusets have exclusive CPU conflicts + * @cs1: first cpuset to check + * @cs2: second cpuset to check + * + * Returns: true if CPU exclusivity conflict exists, false otherwise + * + * Conflict detection rules: + * 1. If either cpuset is CPU exclusive, they must be mutually exclusive + * 2. exclusive_cpus masks cannot intersect between cpusets + * 3. The allowed CPUs of one cpuset cannot be a subset of another's exclu= sive CPUs + */ +static inline bool cpus_excl_conflict(struct cpuset *cs1, struct cpuset *c= s2) +{ + /* If either cpuset is exclusive, check if they are mutually exclusive */ + if (is_cpu_exclusive(cs1) || is_cpu_exclusive(cs2)) + return !cpusets_are_exclusive(cs1, cs2); + + /* Exclusive_cpus cannot intersect */ + if (cpumask_intersects(cs1->exclusive_cpus, cs2->exclusive_cpus)) + return true; + + /* The cpus_allowed of one cpuset cannot be a subset of another cpuset's = exclusive_cpus */ + if (!cpumask_empty(cs1->cpus_allowed) && + cpumask_subset(cs1->cpus_allowed, cs2->exclusive_cpus)) + return true; + + if (!cpumask_empty(cs2->cpus_allowed) && + cpumask_subset(cs2->cpus_allowed, cs1->exclusive_cpus)) + return true; + + return false; +} + +static inline bool mems_excl_conflict(struct cpuset *cs1, struct cpuset *c= s2) +{ + if ((is_mem_exclusive(cs1) || is_mem_exclusive(cs2))) + return nodes_intersects(cs1->mems_allowed, cs2->mems_allowed); + return false; +} + /* * validate_change() - Used to validate that any proposed cpuset change * follows the structural rules for cpusets. @@ -663,38 +704,11 @@ static int validate_change(struct cpuset *cur, struct= cpuset *trial) */ ret =3D -EINVAL; cpuset_for_each_child(c, css, par) { - bool txset, cxset; /* Are exclusive_cpus set? */ - if (c =3D=3D cur) continue; - - txset =3D !cpumask_empty(trial->exclusive_cpus); - cxset =3D !cpumask_empty(c->exclusive_cpus); - if (is_cpu_exclusive(trial) || is_cpu_exclusive(c) || - (txset && cxset)) { - if (!cpusets_are_exclusive(trial, c)) - goto out; - } else if (txset || cxset) { - struct cpumask *xcpus, *acpus; - - /* - * When just one of the exclusive_cpus's is set, - * cpus_allowed of the other cpuset, if set, cannot be - * a subset of it or none of those CPUs will be - * available if these exclusive CPUs are activated. - */ - if (txset) { - xcpus =3D trial->exclusive_cpus; - acpus =3D c->cpus_allowed; - } else { - xcpus =3D c->exclusive_cpus; - acpus =3D trial->cpus_allowed; - } - if (!cpumask_empty(acpus) && cpumask_subset(acpus, xcpus)) - goto out; - } - if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && - nodes_intersects(trial->mems_allowed, c->mems_allowed)) + if (cpus_excl_conflict(trial, c)) + goto out; + if (mems_excl_conflict(trial, c)) goto out; } =20 --=20 2.34.1