Re: [PATCH v4] locking/rwsem: Make handoff bit handling more consistent

[Waiman Long]

On 11/15/21 18:07, Peter Zijlstra wrote:
> On Mon, Nov 15, 2021 at 05:29:10PM -0500, Waiman Long wrote:
> > The handoff_set flag can only be true for a first waiter. A random waiter in
> > the middle of a wait queue will never has this flag set.
> >
> > This flag is set in two places in rwsem_try_write_lock():
> Bah, I thought it would unconditionally propagate the bit from @count. I
> missed the early exit :/
I am going to restructure the code there to make it easier to see that 
only the first waiter will have this bit set to avoid this confusion.

Cheers,
Longman