Re: [PATCH 2/2] xen/rwlock: add check_lock() handling to rwlocks

[Jürgen Groß <jgross@xxxxxxxx>]

On 30.10.20 16:13, Jürgen Groß wrote:
> On 30.10.20 16:10, Jan Beulich wrote:
> > On 30.10.2020 15:25, Juergen Gross wrote:
> > > --- a/xen/include/xen/rwlock.h
> > > +++ b/xen/include/xen/rwlock.h
> > > @@ -65,7 +65,11 @@ static inline int _read_trylock(rwlock_t *lock)
> > >            * arch_lock_acquire_barrier().
> > >            */
> > >           if ( likely(_can_read_lock(cnts)) )
> > > +        {
> > > +            check_lock(&lock->lock.debug, true);
> > >               return 1;
> > > +        }
> > Why not unconditionally earlier in the function?
> Its trylock, so we don't want to call check_lock() without having
> got the lock.
Hmm, OTOH we do so for spinlocks, too.

So maybe its really better to move it up.


Juergen