From: Sebastien Laveze <sebastien.laveze@oss.nxp.com>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users@vger.kernel.org
Subject: Re: timerfd performances
Date: Fri, 22 Jan 2021 14:23:06 +0100 [thread overview]
Message-ID: <0374b95d874d2525f4f354de600b62d369068017.camel@oss.nxp.com> (raw)
In-Reply-To: <20210122123057.72aeag672rh3omcw@linutronix.de>
On Fri, 2021-01-22 at 13:30 +0100, Sebastian Andrzej Siewior wrote:
> Splitting the timer-wakeups back into ktimersoftd would look like
> helping. But note that all timer wake ups would happen there - even the
> accumulated case where we have to wake 100 tasks at once. This would
> then probably ask for split on SCHED_OTHER vs RT tasks like it is done
> for clock_nanosleep().
I didn't know there was a difference in the wakeup mechanism when using
clock_nanosleep if the task was RT or not but that makes sense indeed.
(just looking at __hrtimer_init_sleeper)
So basically, if re-introduced, the ktimersoftd (with a RT priority by
default) would only handle the wakeup of RT tasks ? Other non-RT
POSIX/timerfd users would still be woken-up by ksoftirqd ?
>
> Sebastian
Thx,
Seb
next prev parent reply other threads:[~2021-01-22 13:24 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-18 16:10 timerfd performances Sebastien Laveze
2021-01-22 12:30 ` Sebastian Andrzej Siewior
2021-01-22 13:23 ` Sebastien Laveze [this message]
2021-01-22 14:07 ` Sebastian Andrzej Siewior
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