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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: sched_core_balance() releasing interrupts with pi_lock held
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On 2022-03-16 17:18:41 [+0100], To Steven Rostedt wrote:
> on top my problems are gone. Let me do some testing and then I would
> patch unless PeterZ does the yelling :)

so the long irq-off section is latency wise less than optimal. A
testcase went from ~40 to 140us. And then there is this:
| NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #80!!!
| NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #10!!!

which might be RT-only.
I *think* we want first the buggy part gone and then the latency fixed.

> > > Thanks,
> > > 
> > > -- Steve

Sebastian