Re: [PATCH] sched: Prevent raising SCHED_SOFTIRQ when CPU is !active

From: Thomas Gleixner
Date: Wed Dec 16 2020 - 05:11:19 EST


On Wed, Dec 16 2020 at 09:19, Peter Zijlstra wrote:
> On Tue, Dec 15, 2020 at 06:52:49PM +0100, Thomas Gleixner wrote:
>> I might be missing something, but how is the CPU which runs the pinned
>> kernel thread, i.e. the hotplug thread, supposed to go idle between the
>> two calls?
>
> Take a mutex or something other daft. My disabling preemption around it
> we basically assert the two functions are non-blocking and none of that
> cruft matters.

That'd be really daft, but yes we can do that for paranoia sake.

Thanks,

tglx