Re: [PATCH] locking/percpu-rwsem: Add DEFINE_PERCPU_RWSEM(), use it to initialize cgroup_threadgroup_rwsem

[Ingo Molnar]

* Oleg Nesterov <oleg@xxxxxxxxxx> wrote:

> On 04/24, Ingo Molnar wrote:
> >
> > > -#define DEFINE_STATIC_PERCPU_RWSEM(name)				\
> > > +#define __DEFINE_PERCPU_RWSEM(name, is_static)				\
> > >  static DEFINE_PER_CPU(unsigned int, __percpu_rwsem_rc_##name);		\
> > > -static struct percpu_rw_semaphore name = {				\
> > > +is_static struct percpu_rw_semaphore name = {				\
> > >  	.rss = __RCU_SYNC_INITIALIZER(name.rss),			\
> > >  	.read_count = &__percpu_rwsem_rc_##name,			\
> > >  	.rw_sem = __RWSEM_INITIALIZER(name.rw_sem),			\
> > >  	.writer = __RCUWAIT_INITIALIZER(name.writer),			\
> > >  }
> > > +#define DEFINE_PERCPU_RWSEM(name)		\
> > > +	__DEFINE_PERCPU_RWSEM(name, /* not static */)
> > > +#define DEFINE_STATIC_PERCPU_RWSEM(name)	\
> > > +	__DEFINE_PERCPU_RWSEM(name, static)
> >
> > Which tree is this against? It doesn't apply to tip:master nor latest
> 
> OOPS, sorry Ingo!
> 
> I forgot that the change above depends on another cleanup I sent to Paul,
> 
> 	[PATCH] rcu/sync: kill rcu_sync_type/gp_type
> 	https://lore.kernel.org/lkml/20190423120724.GA6132@xxxxxxxxxx/
> 
> which does
> 
> 	-       .rss = __RCU_SYNC_INITIALIZER(name.rss, RCU_SCHED_SYNC),        \
> 	+       .rss = __RCU_SYNC_INITIALIZER(name.rss),                        \
> 
> so lets forget it for now, or may be Paul can take this patch too.

No problem, and both rwsem patches you sent seem fine to me:

Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
 
Thanks,

	Ingo