From nobody Sat Feb 7 23:48:18 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 5879D278157 for ; Mon, 3 Nov 2025 01:34:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762133694; cv=none; b=QP2xXjMhImcazQfht8wao32z1mKA8+XdqZkbXhpFO2GQKvRuAF4a5ruW465tyQuHzIye9htf4tITW5GM8GeT+R5X1a/gCppo4RkkKrBpKxC7HTO6aVGxCZux7WeZwo0DyKQi8ZEGrK8zq7n4cvBZ4GrpNPG9eYw+QkHGxLM5Qhg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762133694; c=relaxed/simple; bh=bLOIcuYxGdqqH4c1xNAF95pFhgwNBr4Zr+aFbWJ8NHM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hSCCHJN8LJI/7T4ffnXsD05mGFayj5epIQ5da4bxLqYErSO6xFF8qT8EyII1uvIjLM8dComS4X5poIj01cc7pkONHyx3V4J8vVyMMvG8IJyoToYjZ6bz8zYtyisw8Qj446j+lKhhIkkqdP8YdTPEnPUaTdcOdsvDft9MRO3NMqs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=MjyWiCv/; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MjyWiCv/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1762133692; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=b3qTcqDPoDGNC2eYnrVCPzC7q7gU+8tNLIE10nesQIE=; b=MjyWiCv/JMbDwpv5letiCobWzSzjHbX/AuH3ug7vXo9qWEW5VwNWsWp8xmTyuKEfijmHJu pItWx+19gqfsU/UHsc4VA2e5AQg6QhdcbNxasI4T1pJpLyrcNYYMbQKPmFPm8Purqf0xEg 4pN2FNlajWmGmg/yb1XMNFgkC741kQg= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-60-yNG1Rmc_PFidsJhmCl-IQQ-1; Sun, 02 Nov 2025 20:34:45 -0500 X-MC-Unique: yNG1Rmc_PFidsJhmCl-IQQ-1 X-Mimecast-MFC-AGG-ID: yNG1Rmc_PFidsJhmCl-IQQ_1762133683 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 23F631956048; Mon, 3 Nov 2025 01:34:43 +0000 (UTC) Received: from llong-thinkpadp16vgen1.westford.csb (unknown [10.22.88.7]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0DC671955BE3; Mon, 3 Nov 2025 01:34:40 +0000 (UTC) From: Waiman Long To: Tejun Heo , Johannes Weiner , =?UTF-8?q?Michal=20Koutn=C3=BD?= Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Ridong , Gabriele Monaco , Frederic Weisbecker , Waiman Long Subject: [cgroup/for-6.19 PATCH 1/3] cgroup/cpuset: Rename update_unbound_workqueue_cpumask() to update_isolation_cpumasks() Date: Sun, 2 Nov 2025 20:34:09 -0500 Message-ID: <20251103013411.239610-2-longman@redhat.com> In-Reply-To: <20251103013411.239610-1-longman@redhat.com> References: <20251103013411.239610-1-longman@redhat.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-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" From: Gabriele Monaco update_unbound_workqueue_cpumask() updates unbound workqueues settings when there's a change in isolated CPUs, but it can be used for other subsystems requiring updated when isolated CPUs change. Generalise the name to update_isolation_cpumasks() to prepare for other functions unrelated to workqueues to be called in that spot. [longman: Change the function name to update_isolation_cpumasks()] Acked-by: Frederic Weisbecker Acked-by: Waiman Long Signed-off-by: Gabriele Monaco Signed-off-by: Waiman Long Reviewed-by: Chen Ridong --- kernel/cgroup/cpuset.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 7aef59ea9627..da770dac955e 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1393,7 +1393,7 @@ static bool partition_xcpus_del(int old_prs, struct c= puset *parent, return isolcpus_updated; } =20 -static void update_unbound_workqueue_cpumask(bool isolcpus_updated) +static void update_isolation_cpumasks(bool isolcpus_updated) { int ret; =20 @@ -1557,7 +1557,7 @@ static int remote_partition_enable(struct cpuset *cs,= int new_prs, list_add(&cs->remote_sibling, &remote_children); cpumask_copy(cs->effective_xcpus, tmp->new_cpus); spin_unlock_irq(&callback_lock); - update_unbound_workqueue_cpumask(isolcpus_updated); + update_isolation_cpumasks(isolcpus_updated); cpuset_force_rebuild(); cs->prs_err =3D 0; =20 @@ -1598,7 +1598,7 @@ static void remote_partition_disable(struct cpuset *c= s, struct tmpmasks *tmp) compute_excpus(cs, cs->effective_xcpus); reset_partition_data(cs); spin_unlock_irq(&callback_lock); - update_unbound_workqueue_cpumask(isolcpus_updated); + update_isolation_cpumasks(isolcpus_updated); cpuset_force_rebuild(); =20 /* @@ -1667,7 +1667,7 @@ static void remote_cpus_update(struct cpuset *cs, str= uct cpumask *xcpus, if (xcpus) cpumask_copy(cs->exclusive_cpus, xcpus); spin_unlock_irq(&callback_lock); - update_unbound_workqueue_cpumask(isolcpus_updated); + update_isolation_cpumasks(isolcpus_updated); if (adding || deleting) cpuset_force_rebuild(); =20 @@ -2011,7 +2011,7 @@ static int update_parent_effective_cpumask(struct cpu= set *cs, int cmd, tmp->delmask); =20 spin_unlock_irq(&callback_lock); - update_unbound_workqueue_cpumask(isolcpus_updated); + update_isolation_cpumasks(isolcpus_updated); =20 if ((old_prs !=3D new_prs) && (cmd =3D=3D partcmd_update)) update_partition_exclusive_flag(cs, new_prs); @@ -3029,7 +3029,7 @@ static int update_prstate(struct cpuset *cs, int new_= prs) else if (isolcpus_updated) isolated_cpus_update(old_prs, new_prs, cs->effective_xcpus); spin_unlock_irq(&callback_lock); - update_unbound_workqueue_cpumask(isolcpus_updated); + update_isolation_cpumasks(isolcpus_updated); =20 /* Force update if switching back to member & update effective_xcpus */ update_cpumasks_hier(cs, &tmpmask, !new_prs); --=20 2.51.1 From nobody Sat Feb 7 23:48:18 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 AE1CB277C9D for ; Mon, 3 Nov 2025 01:34:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762133692; cv=none; b=uEl+aza316zsIjm/O4kYhujtsR96zzpzQ93yqSBVWvLl1akqKVzJXDGa3wCYp2dCb5unKcnLAgDPa8Jg1O4xbDVkhQOH6cORkS9gE/48qqEwgdtgFhpwG9jzsXd4abwoKhriAklgR9r1mR8gHEqyeLyv7HCgfmx53Fv4LaihASA= ARC-Message-Signature: i=1; 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Mon, 3 Nov 2025 01:34:45 +0000 (UTC) Received: from llong-thinkpadp16vgen1.westford.csb (unknown [10.22.88.7]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 695B71956056; Mon, 3 Nov 2025 01:34:43 +0000 (UTC) From: Waiman Long To: Tejun Heo , Johannes Weiner , =?UTF-8?q?Michal=20Koutn=C3=BD?= Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Ridong , Gabriele Monaco , Frederic Weisbecker , Waiman Long Subject: [cgroup/for-6.19 PATCH 2/3] cgroup/cpuset: Fail if isolated and nohz_full don't leave any housekeeping Date: Sun, 2 Nov 2025 20:34:10 -0500 Message-ID: <20251103013411.239610-3-longman@redhat.com> In-Reply-To: <20251103013411.239610-1-longman@redhat.com> References: <20251103013411.239610-1-longman@redhat.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-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" From: Gabriele Monaco Currently the user can set up isolated cpus via cpuset and nohz_full in such a way that leaves no housekeeping CPU (i.e. no CPU that is neither domain isolated nor nohz full). This can be a problem for other subsystems (e.g. the timer wheel imgration). Prevent this configuration by blocking any assignation that would cause the union of domain isolated cpus and nohz_full to covers all CPUs. Acked-by: Frederic Weisbecker Reviewed-by: Waiman Long Signed-off-by: Gabriele Monaco Signed-off-by: Waiman Long --- kernel/cgroup/cpuset.c | 67 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 66 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index da770dac955e..d6d459c95d82 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1329,6 +1329,19 @@ static void isolated_cpus_update(int old_prs, int ne= w_prs, struct cpumask *xcpus cpumask_andnot(isolated_cpus, isolated_cpus, xcpus); } =20 +/* + * isolated_cpus_should_update - Returns if the isolated_cpus mask needs u= pdate + * @prs: new or old partition_root_state + * @parent: parent cpuset + * Return: true if isolated_cpus needs modification, false otherwise + */ +static bool isolated_cpus_should_update(int prs, struct cpuset *parent) +{ + if (!parent) + parent =3D &top_cpuset; + return prs !=3D parent->partition_root_state; +} + /* * partition_xcpus_add - Add new exclusive CPUs to partition * @new_prs: new partition_root_state @@ -1393,6 +1406,42 @@ static bool partition_xcpus_del(int old_prs, struct = cpuset *parent, return isolcpus_updated; } =20 +/* + * isolated_cpus_can_update - check for isolated & nohz_full conflicts + * @add_cpus: cpu mask for cpus that are going to be isolated + * @del_cpus: cpu mask for cpus that are no longer isolated, can be NULL + * Return: false if there is conflict, true otherwise + * + * If nohz_full is enabled and we have isolated CPUs, their combination mu= st + * still leave housekeeping CPUs. + */ +static bool isolated_cpus_can_update(struct cpumask *add_cpus, + struct cpumask *del_cpus) +{ + cpumask_var_t full_hk_cpus; + int res =3D true; + + if (!housekeeping_enabled(HK_TYPE_KERNEL_NOISE)) + return true; + + if (del_cpus && cpumask_weight_and(del_cpus, + housekeeping_cpumask(HK_TYPE_KERNEL_NOISE))) + return true; + + if (!alloc_cpumask_var(&full_hk_cpus, GFP_KERNEL)) + return false; + + cpumask_and(full_hk_cpus, housekeeping_cpumask(HK_TYPE_KERNEL_NOISE), + housekeeping_cpumask(HK_TYPE_DOMAIN)); + cpumask_andnot(full_hk_cpus, full_hk_cpus, isolated_cpus); + cpumask_and(full_hk_cpus, full_hk_cpus, cpu_active_mask); + if (!cpumask_weight_andnot(full_hk_cpus, add_cpus)) + res =3D false; + + free_cpumask_var(full_hk_cpus); + return res; +} + static void update_isolation_cpumasks(bool isolcpus_updated) { int ret; @@ -1551,6 +1600,9 @@ static int remote_partition_enable(struct cpuset *cs,= int new_prs, if (!cpumask_intersects(tmp->new_cpus, cpu_active_mask) || cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus)) return PERR_INVCPUS; + if (isolated_cpus_should_update(new_prs, NULL) && + !isolated_cpus_can_update(tmp->new_cpus, NULL)) + return PERR_HKEEPING; =20 spin_lock_irq(&callback_lock); isolcpus_updated =3D partition_xcpus_add(new_prs, NULL, tmp->new_cpus); @@ -1650,6 +1702,9 @@ static void remote_cpus_update(struct cpuset *cs, str= uct cpumask *xcpus, else if (cpumask_intersects(tmp->addmask, subpartitions_cpus) || cpumask_subset(top_cpuset.effective_cpus, tmp->addmask)) cs->prs_err =3D PERR_NOCPUS; + else if (isolated_cpus_should_update(prs, NULL) && + !isolated_cpus_can_update(tmp->addmask, tmp->delmask)) + cs->prs_err =3D PERR_HKEEPING; if (cs->prs_err) goto invalidate; } @@ -1988,6 +2043,12 @@ static int update_parent_effective_cpumask(struct cp= uset *cs, int cmd, return err; } =20 + if (deleting && isolated_cpus_should_update(new_prs, parent) && + !isolated_cpus_can_update(tmp->delmask, tmp->addmask)) { + cs->prs_err =3D PERR_HKEEPING; + return PERR_HKEEPING; + } + /* * Change the parent's effective_cpus & effective_xcpus (top cpuset * only). @@ -2994,7 +3055,11 @@ static int update_prstate(struct cpuset *cs, int new= _prs) * A change in load balance state only, no change in cpumasks. * Need to update isolated_cpus. */ - isolcpus_updated =3D true; + if ((new_prs =3D=3D PRS_ISOLATED) && + !isolated_cpus_can_update(cs->effective_xcpus, NULL)) + err =3D PERR_HKEEPING; + else + isolcpus_updated =3D true; } else { /* * Switching back to member is always allowed even if it --=20 2.51.1 From nobody Sat Feb 7 23:48:18 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 B592C27603A for ; 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Sun, 02 Nov 2025 20:34:49 -0500 X-MC-Unique: YGL8PWjYMQSazsrYH1NT8Q-1 X-Mimecast-MFC-AGG-ID: YGL8PWjYMQSazsrYH1NT8Q_1762133687 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CCDC8195608E; Mon, 3 Nov 2025 01:34:47 +0000 (UTC) Received: from llong-thinkpadp16vgen1.westford.csb (unknown [10.22.88.7]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8D35C1956056; Mon, 3 Nov 2025 01:34:45 +0000 (UTC) From: Waiman Long To: Tejun Heo , Johannes Weiner , =?UTF-8?q?Michal=20Koutn=C3=BD?= Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Ridong , Gabriele Monaco , Frederic Weisbecker , Waiman Long Subject: [cgroup/for-6.19 PATCH 3/3] cgroup/cpuset: Globally track isolated_cpus update Date: Sun, 2 Nov 2025 20:34:11 -0500 Message-ID: <20251103013411.239610-4-longman@redhat.com> In-Reply-To: <20251103013411.239610-1-longman@redhat.com> References: <20251103013411.239610-1-longman@redhat.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-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" The current cpuset code passes a local isolcpus_updated flag around in a number of functions to determine if external isolation related cpumasks like wq_unbound_cpumask should be updated. It is a bit cumbersome and makes the code more complex. Simplify the code by using a global boolean flag "isolated_cpus_updating" to track this. This flag will be set in isolated_cpus_update() and cleared in update_isolation_cpumasks(). No functional change is expected. Signed-off-by: Waiman Long --- kernel/cgroup/cpuset.c | 74 ++++++++++++++++++++---------------------- 1 file changed, 35 insertions(+), 39 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index d6d459c95d82..406a1c3789f5 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -81,6 +81,13 @@ static cpumask_var_t subpartitions_cpus; */ static cpumask_var_t isolated_cpus; =20 +/* + * isolated_cpus updating flag (protected by cpuset_mutex) + * Set if isolated_cpus is going to be updated in the current + * cpuset_mutex crtical section. + */ +static bool isolated_cpus_updating; + /* * Housekeeping (HK_TYPE_DOMAIN) CPUs at boot */ @@ -1327,13 +1334,14 @@ static void isolated_cpus_update(int old_prs, int n= ew_prs, struct cpumask *xcpus cpumask_or(isolated_cpus, isolated_cpus, xcpus); else cpumask_andnot(isolated_cpus, isolated_cpus, xcpus); + + isolated_cpus_updating =3D true; } =20 /* * isolated_cpus_should_update - Returns if the isolated_cpus mask needs u= pdate * @prs: new or old partition_root_state * @parent: parent cpuset - * Return: true if isolated_cpus needs modification, false otherwise */ static bool isolated_cpus_should_update(int prs, struct cpuset *parent) { @@ -1347,15 +1355,12 @@ static bool isolated_cpus_should_update(int prs, st= ruct cpuset *parent) * @new_prs: new partition_root_state * @parent: parent cpuset * @xcpus: exclusive CPUs to be added - * Return: true if isolated_cpus modified, false otherwise * * Remote partition if parent =3D=3D NULL */ -static bool partition_xcpus_add(int new_prs, struct cpuset *parent, +static void partition_xcpus_add(int new_prs, struct cpuset *parent, struct cpumask *xcpus) { - bool isolcpus_updated; - WARN_ON_ONCE(new_prs < 0); lockdep_assert_held(&callback_lock); if (!parent) @@ -1365,13 +1370,11 @@ static bool partition_xcpus_add(int new_prs, struct= cpuset *parent, if (parent =3D=3D &top_cpuset) cpumask_or(subpartitions_cpus, subpartitions_cpus, xcpus); =20 - isolcpus_updated =3D (new_prs !=3D parent->partition_root_state); - if (isolcpus_updated) + if (new_prs !=3D parent->partition_root_state) isolated_cpus_update(parent->partition_root_state, new_prs, xcpus); =20 cpumask_andnot(parent->effective_cpus, parent->effective_cpus, xcpus); - return isolcpus_updated; } =20 /* @@ -1379,15 +1382,12 @@ static bool partition_xcpus_add(int new_prs, struct= cpuset *parent, * @old_prs: old partition_root_state * @parent: parent cpuset * @xcpus: exclusive CPUs to be removed - * Return: true if isolated_cpus modified, false otherwise * * Remote partition if parent =3D=3D NULL */ -static bool partition_xcpus_del(int old_prs, struct cpuset *parent, +static void partition_xcpus_del(int old_prs, struct cpuset *parent, struct cpumask *xcpus) { - bool isolcpus_updated; - WARN_ON_ONCE(old_prs < 0); lockdep_assert_held(&callback_lock); if (!parent) @@ -1396,14 +1396,12 @@ static bool partition_xcpus_del(int old_prs, struct= cpuset *parent, if (parent =3D=3D &top_cpuset) cpumask_andnot(subpartitions_cpus, subpartitions_cpus, xcpus); =20 - isolcpus_updated =3D (old_prs !=3D parent->partition_root_state); - if (isolcpus_updated) + if (old_prs !=3D parent->partition_root_state) isolated_cpus_update(old_prs, parent->partition_root_state, xcpus); =20 cpumask_and(xcpus, xcpus, cpu_active_mask); cpumask_or(parent->effective_cpus, parent->effective_cpus, xcpus); - return isolcpus_updated; } =20 /* @@ -1442,17 +1440,24 @@ static bool isolated_cpus_can_update(struct cpumask= *add_cpus, return res; } =20 -static void update_isolation_cpumasks(bool isolcpus_updated) +/* + * update_isolation_cpumasks - Update external isolation related CPU masks + * + * The following external CPU masks will be updated if necessary: + * - workqueue unbound cpumask + */ +static void update_isolation_cpumasks(void) { int ret; =20 - lockdep_assert_cpus_held(); - - if (!isolcpus_updated) + if (!isolated_cpus_updating) return; =20 + lockdep_assert_cpus_held(); + ret =3D workqueue_unbound_exclude_cpumask(isolated_cpus); WARN_ON_ONCE(ret < 0); + isolated_cpus_updating =3D false; } =20 /** @@ -1577,8 +1582,6 @@ static inline bool is_local_partition(struct cpuset *= cs) static int remote_partition_enable(struct cpuset *cs, int new_prs, struct tmpmasks *tmp) { - bool isolcpus_updated; - /* * The user must have sysadmin privilege. */ @@ -1605,11 +1608,11 @@ static int remote_partition_enable(struct cpuset *c= s, int new_prs, return PERR_HKEEPING; =20 spin_lock_irq(&callback_lock); - isolcpus_updated =3D partition_xcpus_add(new_prs, NULL, tmp->new_cpus); + partition_xcpus_add(new_prs, NULL, tmp->new_cpus); list_add(&cs->remote_sibling, &remote_children); cpumask_copy(cs->effective_xcpus, tmp->new_cpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(isolcpus_updated); + update_isolation_cpumasks(); cpuset_force_rebuild(); cs->prs_err =3D 0; =20 @@ -1632,15 +1635,12 @@ static int remote_partition_enable(struct cpuset *c= s, int new_prs, */ static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *t= mp) { - bool isolcpus_updated; - WARN_ON_ONCE(!is_remote_partition(cs)); WARN_ON_ONCE(!cpumask_subset(cs->effective_xcpus, subpartitions_cpus)); =20 spin_lock_irq(&callback_lock); list_del_init(&cs->remote_sibling); - isolcpus_updated =3D partition_xcpus_del(cs->partition_root_state, - NULL, cs->effective_xcpus); + partition_xcpus_del(cs->partition_root_state, NULL, cs->effective_xcpus); if (cs->prs_err) cs->partition_root_state =3D -cs->partition_root_state; else @@ -1650,7 +1650,7 @@ static void remote_partition_disable(struct cpuset *c= s, struct tmpmasks *tmp) compute_excpus(cs, cs->effective_xcpus); reset_partition_data(cs); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(isolcpus_updated); + update_isolation_cpumasks(); cpuset_force_rebuild(); =20 /* @@ -1675,7 +1675,6 @@ static void remote_cpus_update(struct cpuset *cs, str= uct cpumask *xcpus, { bool adding, deleting; int prs =3D cs->partition_root_state; - int isolcpus_updated =3D 0; =20 if (WARN_ON_ONCE(!is_remote_partition(cs))) return; @@ -1711,9 +1710,9 @@ static void remote_cpus_update(struct cpuset *cs, str= uct cpumask *xcpus, =20 spin_lock_irq(&callback_lock); if (adding) - isolcpus_updated +=3D partition_xcpus_add(prs, NULL, tmp->addmask); + partition_xcpus_add(prs, NULL, tmp->addmask); if (deleting) - isolcpus_updated +=3D partition_xcpus_del(prs, NULL, tmp->delmask); + partition_xcpus_del(prs, NULL, tmp->delmask); /* * Need to update effective_xcpus and exclusive_cpus now as * update_sibling_cpumasks() below may iterate back to the same cs. @@ -1722,7 +1721,7 @@ static void remote_cpus_update(struct cpuset *cs, str= uct cpumask *xcpus, if (xcpus) cpumask_copy(cs->exclusive_cpus, xcpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(isolcpus_updated); + update_isolation_cpumasks(); if (adding || deleting) cpuset_force_rebuild(); =20 @@ -1803,7 +1802,6 @@ static int update_parent_effective_cpumask(struct cpu= set *cs, int cmd, int deleting; /* Deleting cpus from parent's effective_cpus */ int old_prs, new_prs; int part_error =3D PERR_NONE; /* Partition error? */ - int isolcpus_updated =3D 0; struct cpumask *xcpus =3D user_xcpus(cs); bool nocpu; =20 @@ -2065,14 +2063,12 @@ static int update_parent_effective_cpumask(struct c= puset *cs, int cmd, * and vice versa. */ if (adding) - isolcpus_updated +=3D partition_xcpus_del(old_prs, parent, - tmp->addmask); + partition_xcpus_del(old_prs, parent, tmp->addmask); if (deleting) - isolcpus_updated +=3D partition_xcpus_add(new_prs, parent, - tmp->delmask); + partition_xcpus_add(new_prs, parent, tmp->delmask); =20 spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(isolcpus_updated); + update_isolation_cpumasks(); =20 if ((old_prs !=3D new_prs) && (cmd =3D=3D partcmd_update)) update_partition_exclusive_flag(cs, new_prs); @@ -3094,7 +3090,7 @@ static int update_prstate(struct cpuset *cs, int new_= prs) else if (isolcpus_updated) isolated_cpus_update(old_prs, new_prs, cs->effective_xcpus); spin_unlock_irq(&callback_lock); - update_isolation_cpumasks(isolcpus_updated); + update_isolation_cpumasks(); =20 /* Force update if switching back to member & update effective_xcpus */ update_cpumasks_hier(cs, &tmpmask, !new_prs); --=20 2.51.1