Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU bandwidth

From	Steven Rostedt <rostedt@goodmis.org>
Newsgroups	linux.kernel
Subject	Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU bandwidth
Date	2017-03-25 03:40 +0100
Message-ID	<toJMt-2y5-3@gated-at.bofh.it> (permalink)
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On Fri, 24 Mar 2017 22:58:27 +0100
luca abeni <luca.abeni@santannapisa.it> wrote:

> Hi Peter,
> 
> On Fri, 24 Mar 2017 15:00:15 +0100
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Fri, Mar 24, 2017 at 04:52:58AM +0100, luca abeni wrote:
> >   
> > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > index 20c62e7..efa88eb 100644
> > > --- a/kernel/sched/core.c
> > > +++ b/kernel/sched/core.c
> > > @@ -6716,6 +6716,12 @@ static void sched_dl_do_global(void)
> > >  		raw_spin_unlock_irqrestore(&dl_b->lock, flags);
> > >  
> > >  		rcu_read_unlock_sched();
> > > +		if (dl_b->bw == -1)
> > > +			cpu_rq(cpu)->dl.deadline_bw_inv = 1 << 8;
> > > +		else
> > > +			cpu_rq(cpu)->dl.deadline_bw_inv =
> > > +				to_ratio(global_rt_runtime(),
> > > +					 global_rt_period()) >>
> > > 12;    
> > 
> > Coding style requires braces here (on both legs of the condition)..  
> 
> Sorry about this; checkpatch did not complain and I did not check the
> coding rules. I'll add the braces.

I'm not sure it's completely documented anywhere.

The brackets are not needed if there's one statement after the if, but
for readability, it's sometimes best to put brackets in if there's more
than one line. That can even include comments. It's not a hard rule,
but more of a preference. I'm personally OK with the above, but Peter
being the maintainer, has the say to give the preference of this kind
of rule.

-- Steve

Thread

[RFC v5 5/9] sched/deadline: do not reclaim the whole CPU bandwidth luca abeni <luca.abeni@santannapisa.it> - 2017-03-23 21:00 +0100
  Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU  bandwidth Peter Zijlstra <peterz@infradead.org> - 2017-03-24 15:10 +0100
    Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU  bandwidth luca abeni <luca.abeni@santannapisa.it> - 2017-03-24 23:00 +0100
      Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU  bandwidth Steven Rostedt <rostedt@goodmis.org> - 2017-03-25 03:40 +0100
        Re: [RFC v5 5/9] sched/deadline: do not reclaim the whole CPU  bandwidth Peter Zijlstra <peterz@infradead.org> - 2017-03-27 10:40 +0200

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