# Re: \[PATCH\] sched: provide scheduler\_ipi() callback in response to smp\_send\_reschedule()

- From: Peter Zijlstra \<peterz@infradead.org\>
- Date: 2011-01-17 20:43:03 
- List: linux-mips
- Page: https://ratatoskr.run/linux-mips/2011/01/8566736
- Thread: https://ratatoskr.run/linux-arm-kernel/2011/01/8566729/t.md

```text
On Tue, 2011-01-18 at 07:31 +1100, Benjamin Herrenschmidt wrote:
> 
> Beware of false positive, I've used "fake" reschedule IPIs in the past
> for other things (like kicking a CPU out of sleep state for unrelated
> reasons). Nothing that I know that is upstream today but some of that
> might come back. I'd like to avoid having to add an atomic to know if
> it's a real reschedule, will the scheduler be smart enough to not bother
> with false positives ? 

Yes it can deal with that, some will be for reschedules, some will be
for ttwu tail ends and x86 too uses this ipi for a few random other
things like kicking kvm out of guest context..
```