Re: [PATCH RT] Align rt_mutex inlining with upstream behavior

From: Sebastian Andrzej Siewior
Date: Mon Feb 13 2017 - 08:24:00 EST


On 2017-02-13 12:20:52 [+0100], Peter Zijlstra wrote:
> > --- a/include/linux/mutex_rt.h
> > +++ b/include/linux/mutex_rt.h
> > @@ -43,7 +43,12 @@ extern void __lockfunc _mutex_unlock(str
> > #define mutex_lock_killable(l) _mutex_lock_killable(l)
> > #define mutex_trylock(l) _mutex_trylock(l)
> > #define mutex_unlock(l) _mutex_unlock(l)
> > +
> > +#ifdef CONFIG_DEBUG_MUTEXES
> > #define mutex_destroy(l) rt_mutex_destroy(&(l)->lock)
> > +#else
> > +static inline void mutex_destroy(struct mutex *lock) {}
> > +#endif
> >
> > #ifdef CONFIG_DEBUG_LOCK_ALLOC
> > # define mutex_lock_nested(l, s) _mutex_lock_nested(l, s)
> > --- a/kernel/locking/rtmutex.c
> > +++ b/kernel/locking/rtmutex.c
> > @@ -2027,8 +2027,7 @@ void rt_mutex_destroy(struct rt_mutex *l
> > lock->magic = NULL;
> > #endif
> > }
> > -
> > -EXPORT_SYMBOL_GPL(rt_mutex_destroy);
> > +EXPORT_SYMBOL(rt_mutex_destroy);
>
> I don't understand:
>
> $ git grep "EXPORT_SYMBOL.*mutex_destroy"
> kernel/locking/mutex-debug.c:EXPORT_SYMBOL_GPL(mutex_destroy);
> kernel/locking/rtmutex.c:EXPORT_SYMBOL_GPL(rt_mutex_destroy);
>
> Your proposed patch makes it different from mainline.

as discussed off-list, I will drop that _GPL removal hunk and keep only
the (first) inline hunk.
!GPL users should compile with !CONFIG_DEBUG_MUTEXES and
!CONFIG_DEBUG_RT_MUTEXES so there should be no regression.

Sebastian