Re: [PATCH] tick/broadcast: Remove redundant code in tick_check_new_device()

[Thomas Gleixner]

On Tue, 14 Nov 2017, Zhenzhong Duan wrote:
> On 2017/11/14 0:54, Thomas Gleixner wrote:
> 
> > On Wed, 8 Nov 2017, Zhenzhong Duan wrote:
> > 
> > > There is no way a timer used as broadcast clockevent device is also used
> > > as
> > > percpu tick clockevent device currently.
> > Correct.
> > 
> > > It's better to put related code in tick_install_broadcast_device(), but I
> > > feel
> > > it's harmless to give it back to the clockevents layer. Pls correct me if
> > > I'm
> > > wrong.
> > You already established, that it _cannot_ be the broadcast device and the
> > per cpu device at the same time. So that condition can never be true. What
> > do you want to put into tick_install_broadcast_device()? This second
> > paragraph doesn't make sense, unless I'm missing something.
> 
> I didn't find the reason in long history logs while the comments saying 'If
> the current device is the broadcast device, do not give it back to the
> clockevents layer !'

To be honest I can't figure it out myself why this was put there, even if I
wrote it myself. Fact is that this is wrong and cannot happen at all.

Thanks,

	tglx