Message-ID: <5a1a6e1f-2d19-e2ff-8f2c-63d185aa057b@redhat.com>
Date:   Wed, 1 Feb 2023 14:17:59 -0500
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Subject: Re: [PATCH 1/2] cpuset: Fix cpuset_cpus_allowed() to not filter
 offline CPUs
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From:   Waiman Long <longman@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
        kernel-team@android.com, Zefan Li <lizefan.x@bytedance.com>,
        Tejun Heo <tj@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org
References: <20230131221719.3176-1-will@kernel.org>
 <20230131221719.3176-2-will@kernel.org>
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On 2/1/23 14:14, Waiman Long wrote:
> One possible solution is to use cpuset_cpus_allowed_fallback() in case 
> none of the cpus in the current cpuset is allowed to be used to run a 
> given task.

It looks like we will need to enhance cpuset_cpus_allowed_fallback() to 
walk up cpuset tree to find one that have useable cpus.

Cheers,
Longman