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Date:   Wed, 4 Aug 2021 18:31:19 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Jens Axboe <axboe@kernel.dk>,
        Peter Zijlstra <peterz@infradead.org>,
        Daniel Wagner <wagi@monom.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-rt-users@vger.kernel.org
Subject: Re: [ANNOUNCE] v5.14-rc4-rt4
Message-ID: <20210804163119.t4c7bkpdk33byxtx@linutronix.de>
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On 2021-08-04 12:25:41 [-0400], Steven Rostedt wrote:
> On Wed, 4 Aug 2021 18:22:31 +0200
> Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> 
> > no preemption happens here with NEED_RESCHED set.
> 
> But if interrupts were disabled, how would NEED_RESCHED be set? As soon
> as you enable interrupts, the interrupt that sets NEED_RESCHED would
> trigger the preemption.

CPU-local wake-ups just set NEED_RESCHED and wait for preempt_enable()
to do the magic. Just because the code not perform wake_up() now does
not mean it will not do so in the future. Also it is here as an example
which might be copied somewhere else.

> -- Steve

Sebastian