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Date: Fri, 5 Oct 2018 13:07:25 +0200
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: Bug or works as intended: signal behaviour on -RT
Message-ID: <20181005110725.jggf75junl7euf3c@linutronix.de>
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To: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>

On 2018-09-26 17:07:02 [+0200], Ralf Ramsauer wrote:
> Hi,
Hi,

> But if I synchronously send a SIGALRM via kill, it will immediately
> arrive. Even a sched_yield() in the busy loop won't help. In order to
> get the signal, I have to leave running/runable with usleep().

a sched_yield() will put you at the end of the runqueue. If this is the
only task in that queue then the task will go back on the CPU.

> Thanks
>   Ralf

Sebastian