On Tue, Dec 18, 2018 at 02:10:31PM +0100, Peter Zijlstra wrote: > On Mon, Dec 17, 2018 at 12:53:10PM -0800, Davidlohr Bueso wrote:
> > So how about the following to reduce some of the performance penalty (at > > the cost of more complexity)? > > I'd rather do it like so, except I'm still conflicted on the naming. > +void wake_q_add(struct wake_q_head *head, struct task_struct *task) > +{ > + if (__wake_q_add(head, task)) > + get_task_struct(task); > +} > + > +void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task) > +{ > + if (!__wake_a_add(head, task)) > + put_task_struct(task); > } That is, in the one case it has internal reference counting, in the other case it consumes the reference counting.