> > > diff --git a/fs/proc/base.c b/fs/proc/base.c
> > > index 968d5ea06e62..a6a8fbdd5a1b 100644
> > > --- a/fs/proc/base.c
> > > +++ b/fs/proc/base.c
> > > @@ -1037,7 +1037,47 @@ static ssize_t oom_adj_read(struct file *file,
> > > char __user *buf, size_t count,
> > > return simple_read_from_buffer(buf, count, ppos, buffer, len);
> > > }
> > >
> > > -static DEFINE_MUTEX(oom_adj_mutex);
> > > +static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
> > > +{
> > > + static DEFINE_MUTEX(oom_adj_mutex);
> >
> > Writers are not excluded for readers!
> > Is this a hot path?
>
> I am not sure I follow you question. This is a write path... Who would
> be the reader?
>
Currently oom_adj_read() and oom_adj_write() are serialized with
task->sighand->siglock, and in this work oom_adj_mutex is introduced to
only keep writers in hose.
Plus, oom_adj_write() and oom_badness() are currently serialized
with task->alloc_lock, and they may be handled in subsequent patches.
thanks
Hillf
