* Wanpeng Li <wanpeng...@linux.intel.com> wrote:
> On Tue, Mar 17, 2015 at 09:13:02AM +0100, Ingo Molnar wrote:
> >
> >* Wanpeng Li <wanpeng...@linux.intel.com> wrote:
> >
> >> Hi Ingo,
> >> On Tue, Mar 17, 2015 at 09:06:13AM +0100, Ingo Molnar wrote:
> >> >
> >> >* Wanpeng Li <wanpeng...@linux.intel.com> wrote:
> >> >
> >> >> Hi Ingo,
> >> >> On Mon, Mar 16, 2015 at 04:01:02PM +0100, Ingo Molnar wrote:
> >> >> >> +
> >> >> >> + /*
> >> >> >> + * If cannot preempt any rq, fallback to pick
> >> >> >> any
> >> >> >> + * online cpu.
> >> >> >
> >> >> >s/If cannot/If we cannot
> >> >> >s/fallback/fall back
> >> >>
> >> >> Will do.
> >> >>
> >> >> >
> >> >> >> + */
> >> >> >> + fallback = true;
> >> >> >> + cpu = cpumask_any_and(cpu_active_mask,
> >> >> >> + tsk_cpus_allowed(p));
> >> >> >
> >> >> >shouldn't be on separate lines - but this is also a sign that the guts
> >> >>
> >> >> Otherwise there is a "WARNING: line over 80 characters".
> >> >
> >> >Yes, but did your reaction to that tool's warning improve the code? I
> >> >don't think so. If do what I suggested and reduce indentation a bit,
> >> >you'll fix the warning _and_ improve the code. Win-win.
> >>
> >> Cool, will do.
> >>
> >> >
> >> >> > of this new code should be in a helper function, not inside
> >> >> > several layers of branches.
> >> >>
> >> >> Do you mean the whole patch should be in a helper function?
> >> >
> >> >Probably.
> >>
> >> Will do.
> >>
> >> >
> >> >> >> + if (cpu >= nr_cpu_ids) {
> >> >> >> + if (dl_bandwidth_enabled()) {
> >> >> >> + /*
> >> >> >> + * Fail to find any suitable
> >> >> >> cpu.
> >> >> >> + * The task will never come
> >> >> >> back!
> >> >> >> + */
> >> >> >> + WARN_ON(1);
> >> >> >
> >> >> > Can this condition happen to users with a non-buggy kernel?
> >> >>
> >> >> What do you prefer? ;-)
> >> >
> >> >That was a yes/no question: can this condition trigger on correctly
> >> >working kernels?
> >>
> >> How about add unlikely() here?
> >
> >Please answer my question: can this condition trigger on correctly
> >working kernels? I think so, but maybe I'm wrong?
>
> I didn't see it happen, I add this by Juri's suggestion, maybe he can
> explain more.
>
> Ping Juri, ;-)
I still haven't seen a satisfactory answer to this question. Please
don't resend patches without clearing questions raised during review.
Thanks,
Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
