Re: [PATCH v4 04/13] locking/spinlock: introduce spin_lock_init_with_key

From: Boqun Feng
Date: Wed Apr 12 2023 - 15:14:57 EST


On Tue, Apr 11, 2023 at 03:05:07PM -0300, Wedson Almeida Filho wrote:
> On Tue, 11 Apr 2023 at 02:46, Wedson Almeida Filho <wedsonaf@xxxxxxxxx> wrote:
> >
> > From: Wedson Almeida Filho <walmeida@xxxxxxxxxxxxx>
> >
> > Rust cannot call C macros, so it has its own macro to create a new lock
> > class when a spin lock is initialised. This new function allows Rust
> > code to pass the lock class it generates to the C implementation.
> >
> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Will Deacon <will@xxxxxxxxxx>
> > Cc: Waiman Long <longman@xxxxxxxxxx>
> > Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@xxxxxxxxx>
> > Signed-off-by: Wedson Almeida Filho <walmeida@xxxxxxxxxxxxx>

Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx>

> > ---
> > v1 -> v2: No changes
> > v2 -> v3: No changes
> > v3 -> v4: No changes
> >
> > include/linux/spinlock.h | 9 +++++++--
> > 1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
> > index be48f1cb1878..cdc92d095133 100644
> > --- a/include/linux/spinlock.h
> > +++ b/include/linux/spinlock.h
> > @@ -327,12 +327,17 @@ static __always_inline raw_spinlock_t *spinlock_check(spinlock_t *lock)
> >
> > #ifdef CONFIG_DEBUG_SPINLOCK
> >
> > +static inline void spin_lock_init_with_key(spinlock_t *lock, const char *name,
> > + struct lock_class_key *key)
> > +{
> > + __raw_spin_lock_init(spinlock_check(lock), name, key, LD_WAIT_CONFIG);
> > +}
> > +
> > # define spin_lock_init(lock) \
> > do { \
> > static struct lock_class_key __key; \
> > \
> > - __raw_spin_lock_init(spinlock_check(lock), \
> > - #lock, &__key, LD_WAIT_CONFIG); \
> > + spin_lock_init_with_key(lock, #lock, &__key); \
> > } while (0)
>
> Peter, the code above is just factoring out spin lock init when
> lockdep is enabled to take a lock class key.
>
> Would you be able to review it?
>
> If it's ok with you, we'd like to carry it through the rust tree
> because we have code that depends on it.

Same ask here ;-) Peter, do you think it's Ok to take it via rust tree?
Thanks!

Regards,
Boqun

>
> Thanks,
> -Wedson
>
> >
> > #else
> > --
> > 2.34.1
> >