Re: [PATCH v2 2/8] sched/topology: Wrappers for sched_domains_mutex

[Waiman Long]

On 3/7/25 10:59 AM, Juri Lelli wrote:
> On 07/03/25 10:19, Waiman Long wrote:
> > On 3/7/25 10:11 AM, Waiman Long wrote:
> > > On 3/6/25 9:10 AM, Juri Lelli wrote:
> > > > Create wrappers for sched_domains_mutex so that it can transparently be
> > > > used on both CONFIG_SMP and !CONFIG_SMP, as some function will need to
> > > > do.
> > > >
> > > > Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> > > > Fixes: 53916d5fd3c0 ("sched/deadline: Check bandwidth overflow
> > > > earlier for hotplug")
> > > > Signed-off-by: Juri Lelli <juri.lelli@xxxxxxxxxx>
> > > > ---
> > > > v1 -> v2: Remove wrappers for the !SMP case as all users are not defined
> > > >             either in that case
> > > > ---
> > > >    include/linux/sched.h   |  2 ++
> > > >    kernel/cgroup/cpuset.c  |  4 ++--
> > > >    kernel/sched/core.c     |  4 ++--
> > > >    kernel/sched/debug.c    |  8 ++++----
> > > >    kernel/sched/topology.c | 12 ++++++++++--
> > > >    5 files changed, 20 insertions(+), 10 deletions(-)
> > > >
> > > > diff --git a/include/linux/sched.h b/include/linux/sched.h
> > > > index 9632e3318e0d..d5f8c161d852 100644
> > > > --- a/include/linux/sched.h
> > > > +++ b/include/linux/sched.h
> > > > @@ -383,6 +383,8 @@ enum uclamp_id {
> > > >    extern struct root_domain def_root_domain;
> > > >    extern struct mutex sched_domains_mutex;
> > > >    #endif
> > > > +extern void sched_domains_mutex_lock(void);
> > > > +extern void sched_domains_mutex_unlock(void);
> > > As discussed in the other thread, move the
> > > sched_domains_mutex_{lock/unlock}{} inside the "#if CONFIG_SMP" block
> > > and define the else part so that it can be used in code block that will
> > > also be compiled in the !CONFIG_SMP case.
> > >
> > > Other than that, the rest looks good to me.
> > Actually, you can also remove sched_domains_mutex from the header and make
> > it static as it is no longer directly accessed.
> Apart from a lockdep_assert_held() in cpuset.c, no? Guess I can create a
> wrapper for that, but is it really better?

I forgot about that. Please ignore this comment.

Thanks,
Longman