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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Austin Schuh <austin.linux@gmail.com>
Cc: linux-rt-users@vger.kernel.org, Brian Silverman <bsilver16384@gmail.com>
Subject: Re: Extra context switches with signalfd on CONFIG_PREEMPT_RT
Date: Thu, 5 Sep 2019 18:02:51 +0200	[thread overview]
Message-ID: <20190905160251.nhgemb3fadw6swgq@linutronix.de> (raw)
In-Reply-To: <CABsbf=Egk6wqEFPTvf9_UtVze80=b38nPzVOdZk-t=QOcUXCWw@mail.gmail.com>

On 2019-08-29 13:55:27 [-0700], Austin Schuh wrote:
> 
> This is still RT, but is pretty inefficient.  Any suggestions on what
> might be going wrong before I start digging in?

there is a pi-boost sched_switch with state R->D  and then de-boost
switch back. This looks like there is a wakeup while a lock is held
which is required by the task that is woken up.

> Thanks,
>   Austin

Sebastian

      reply	other threads:[~2019-09-05 16:02 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-29 20:55 Extra context switches with signalfd on CONFIG_PREEMPT_RT Austin Schuh
2019-09-05 16:02 ` Sebastian Andrzej Siewior [this message]

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