Re: [PATCH v7 1/3] PM / wakeup: Drop wakeup_source_init(), wakeup_source_prepare()

[Tri Vo]

On Mon, Aug 5, 2019 at 1:54 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
>
> Quoting Tri Vo (2019-08-05 10:58:46)
> > diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
> > index ee31d4f8d856..3938892c8903 100644
> > --- a/drivers/base/power/wakeup.c
> > +++ b/drivers/base/power/wakeup.c
> > @@ -72,23 +72,6 @@ static struct wakeup_source deleted_ws = {
> >         .lock =  __SPIN_LOCK_UNLOCKED(deleted_ws.lock),
> >  };
> >
> > -/**
> > - * wakeup_source_prepare - Prepare a new wakeup source for initialization.
> > - * @ws: Wakeup source to prepare.
> > - * @name: Pointer to the name of the new wakeup source.
> > - *
> > - * Callers must ensure that the @name string won't be freed when @ws is still in
> > - * use.
> > - */
> > -void wakeup_source_prepare(struct wakeup_source *ws, const char *name)
> > -{
> > -       if (ws) {
> > -               memset(ws, 0, sizeof(*ws));
> > -               ws->name = name;
> > -       }
> > -}
> > -EXPORT_SYMBOL_GPL(wakeup_source_prepare);
> > -
> >  /**
> >   * wakeup_source_create - Create a struct wakeup_source object.
> >   * @name: Name of the new wakeup source.
> > @@ -96,13 +79,23 @@ EXPORT_SYMBOL_GPL(wakeup_source_prepare);
> >  struct wakeup_source *wakeup_source_create(const char *name)
> >  {
> >         struct wakeup_source *ws;
> > +       const char *ws_name;
> >
> > -       ws = kmalloc(sizeof(*ws), GFP_KERNEL);
> > +       ws = kzalloc(sizeof(*ws), GFP_KERNEL);
> >         if (!ws)
> > -               return NULL;
> > +               goto err_ws;
> > +
> > +       ws_name = kstrdup_const(name, GFP_KERNEL);
> > +       if (!ws_name)
>
> Does this intentionally change this function to return an error if
> 'name' is NULL? Before, wakeup_source_prepare() would just assign
> ws->name to NULL, but now it errors out. I don't see how it's good or
> useful to allow NULL for the wakeup source name, but it is what it is.

Yes, the change to not allow ws->name to be NULL is intentional.