Re: [PATCH v2 3/3] softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.

On 2024-10-29 22:47:21 [+0100], Frederic Weisbecker wrote: > Le Tue, Oct 29, 2024 at 02:52:31PM +0100, Sebastian Andrzej Siewior a écrit : > > On 2024-10-28 15:01:55 [+0100], Frederic Weisbecker wrote: > > > > diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h > > > > index 457151f9

Re: [PATCH v2 3/3] softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.

Le Tue, Oct 29, 2024 at 02:52:31PM +0100, Sebastian Andrzej Siewior a écrit : > On 2024-10-28 15:01:55 [+0100], Frederic Weisbecker wrote: > > > diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h > > > index 457151f9f263d..9637af78087f3 100644 > > > --- a/include/linux/interrupt.h >

Re: [PATCH v2 3/3] softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.

On 2024-10-28 15:01:55 [+0100], Frederic Weisbecker wrote: > > diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h > > index 457151f9f263d..9637af78087f3 100644 > > --- a/include/linux/interrupt.h > > +++ b/include/linux/interrupt.h > > @@ -616,6 +616,50 @@ extern void __raise_softir

Re: [PATCH v2 3/3] softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.

Le Thu, Oct 24, 2024 at 04:55:51PM +0200, Sebastian Andrzej Siewior a écrit : > A timer/ hrtimer softirq is raised in-IRQ context. With threaded > interrupts enabled or on PREEMPT_RT this leads to waking the ksoftirqd > for the processing of the softirq. ksoftirqd runs as SCHED_OTHER which > means

[PATCH v2 3/3] softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.

A timer/ hrtimer softirq is raised in-IRQ context. With threaded interrupts enabled or on PREEMPT_RT this leads to waking the ksoftirqd for the processing of the softirq. ksoftirqd runs as SCHED_OTHER which means it will compete with other tasks for CPU ressources. This can introduce long delays fo