# Re: \[PATCH 1/7\] locking/rwsem: don't resched at the end of optimistic spinning

- From: Peter Zijlstra \<peterz@infradead.org\>
- Date: 2014-08-04 07:55:41 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2014/08/4308690
- Thread: https://ratatoskr.run/linux-api/2014/08/4308602/t.md

```text
On Sun, Aug 03, 2014 at 10:36:16PM -0400, Waiman Long wrote:
> For a fully preemptive kernel, a call to preempt_enable() could
> potentially trigger a task rescheduling event. In the case of rwsem
> optimistic spinning, the task has either gotten the lock or is going
> to sleep soon. So there is no point to do rescheduling here.

Uh what? Why shouldn't we preempt if we've gotten the lock? What if a
FIFO task just woke up? 
```

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