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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Marcelo Tosatti <mtosatti@redhat.com>,
        Chris Friesen <chris.friesen@windriver.com>,
        linux-kernel@vger.kernel.org
Cc:     Christoph Lameter <cl@linux.com>, Vu Tran <vu.tran@windriver.com>,
        Jim Somerville <Jim.Somerville@windriver.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] affine kernel threads to specified cpumask
In-Reply-To: <20200323135414.GA28634@fuller.cnet>
References: <20200323135414.GA28634@fuller.cnet>
Date:   Mon, 23 Mar 2020 17:22:00 +0100
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Marcelo,
Marcelo Tosatti <mtosatti@redhat.com> writes:

the subject lacks a prefix and the CC list a few people.

> This is a kernel enhancement to configure the cpu affinity of kernel
> threads via kernel boot option kthread_cpus=<cpulist>.
>
> With kthread_cpus specified, the cpumask is immediately applied upon
> thread launch. This does not affect kernel threads that specify cpu
> and node.
>
> This allows CPU isolation (that is not allowing certain threads
> to execute on certain CPUs) without using the isolcpus= parameter,
> making it possible to enable load balancing on such CPUs 
> during runtime.

I'm surely missing some background information, but that sentence does
not make any sense to me.

Thanks,

        tglx