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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     John Garry <john.garry@huawei.com>
Cc:     "linux-kernel\@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Marc Zyngier <maz@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: Question on threaded handlers for managed interrupts
In-Reply-To: <874kfxw9zv.ffs@nanos.tec.linutronix.de>
References: <b8c4be8c-1d67-c16c-570e-d3c883c77ea2@huawei.com> <874kfxw9zv.ffs@nanos.tec.linutronix.de>
Date:   Fri, 23 Apr 2021 15:01:23 +0200
Message-ID: <871rb1w3x8.ffs@nanos.tec.linutronix.de>
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John,

On Fri, Apr 23 2021 at 12:50, Thomas Gleixner wrote:
> On Thu, Apr 22 2021 at 17:10, John Garry wrote:
> OTOH, the way how you splitted the handling into hard/thread context
> provides already the base for this.
>
> The missing piece is infrastructure at the irq/scheduler core level to
> handle this transparently.
>
> I have some horrible ideas how to solve that, but I'm sure the scheduler
> wizards can come up with a reasonable and generic solution.

So one thing I forgot to ask is:

Is the thread simply stuck in the while() loop forever or is
this just an endless hardirq/thread/hardirq/thread stream?

Thanks,

        tglx