Re: [PATCH bpf-next v2 3/6] locking/local_lock: Introduce local_trylock_irqsave()

[Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>]

On Thu, Dec 12, 2024 at 7:15 AM Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
>
> > diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h
> > index 8dd71fbbb6d2..2c0f8a49c2d0 100644
> > --- a/include/linux/local_lock_internal.h
> > +++ b/include/linux/local_lock_internal.h
> > @@ -148,6 +163,14 @@ typedef spinlock_t local_lock_t;
> >               __local_lock(lock);                             \
> >       } while (0)
> >
> > +#define __local_trylock_irqsave(lock, flags)                 \
> > +     ({                                                      \
> > +             typecheck(unsigned long, flags);                \
> > +             flags = 0;                                      \
> > +             migrate_disable();                              \
> > +             spin_trylock(this_cpu_ptr((__lock)));           \
>
> You should probably do a migrate_enable() here if the trylock fails.

Great catch. Thanks!