Re: [PATCH v3 4/6] sched/completion: Add wait_for_completion_state()

[Ingo Molnar]

* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Sun, Sep 04, 2022 at 12:46:11PM +0200, Ingo Molnar wrote:
> > 
> > * Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> > 
> > > Allows waiting with a custom @state.
> > > 
> > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> > > ---
> > >  include/linux/completion.h |    1 +
> > >  kernel/sched/completion.c  |    9 +++++++++
> > >  2 files changed, 10 insertions(+)
> > > 
> > > --- a/include/linux/completion.h
> > > +++ b/include/linux/completion.h
> > > @@ -103,6 +103,7 @@ extern void wait_for_completion(struct c
> > >  extern void wait_for_completion_io(struct completion *);
> > >  extern int wait_for_completion_interruptible(struct completion *x);
> > >  extern int wait_for_completion_killable(struct completion *x);
> > > +extern int wait_for_completion_state(struct completion *x, unsigned int state);
> > >  extern unsigned long wait_for_completion_timeout(struct completion *x,
> > >  						   unsigned long timeout);
> > >  extern unsigned long wait_for_completion_io_timeout(struct completion *x,
> > > --- a/kernel/sched/completion.c
> > > +++ b/kernel/sched/completion.c
> > > @@ -247,6 +247,15 @@ int __sched wait_for_completion_killable
> > >  }
> > >  EXPORT_SYMBOL(wait_for_completion_killable);
> > >  
> > > +int __sched wait_for_completion_state(struct completion *x, unsigned int state)
> > > +{
> > > +	long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, state);
> > > +	if (t == -ERESTARTSYS)
> > > +		return t;
> > > +	return 0;
> > 
> > Nit: newline missing after local variable definition.
> 
> Yah, I know, but all the other similar functions there have the same
> defect. I don't much like whitespace patches, so I figured I'd be
> consistent and let it all be for now.

That's not actually true: there's ~7 functions in kernel/sched/completion.c 
with local variables, and only ~2 have this minor stylistic inconsistency 
right now AFAICS. Scheduler-wide the ratio is even lower.

So even if a patch doesn't entirely remove the residual noise, let's not 
add to it, please?

Thanks,

	Ingo