Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

From: Rafael J. Wysocki
Date: Mon Jan 21 2019 - 07:02:21 EST


On Friday, January 18, 2019 5:04:50 PM CET Peter Zijlstra wrote:
> On Fri, Jan 18, 2019 at 10:19:41AM -0500, Joel Fernandes wrote:
> > You should document the variable names in the header comments.
> >
> > Also, this new API appears to conflict with definition of 'freezable' in
> > wait_event_freezable I think,
> >
> > wait_event_freezable - sleep or freeze until condition is true.
> >
> > wait_event_freezable_hrtimeout - sleep but make sure freezer is not blocked.
> > (your API)
> >
> > It seems to me these are 2 different definitions of 'freezing' (or I could be
> > completely confused). But in the first case it calls try_to_freeze after
> > schedule(). In the second case (your new API), it calls freezable_schedule().
> >
> > So I am wondering why is there this difference in the 'meaning of freezable'.
> > In the very least, any such subtle differences should be documented in the
> > header comments IMO.
>
> Also; someone was recently hating on the whole freezing thing (again,
> and rightfully). I just cannot remember who; Rafael you remember?

Nope.