[PATCH] nptl: Remove cancellation checks from sem_{timed}wait (BZ #23006)

[Florian Weimer]

* Adhemerval Zanella:

> In any case, do you think we should make sem_{timed}wait not a cancellation
> entrypoint for 2.30? I can rework the patch if it is the case.

Do we have any other form of blocking synchronization that is
cancellable?  If not, a cancellable semaphore wait operation would make
sense.  But then we should perform the cancellation check on the fast
path, too.

Thanks,
Florian