Re: [PATCH 17/54] gpu: drm: replace cpumask_weight with cpumask_empty where appropriate

[Tvrtko Ursulin]

On 25/01/2022 18:16, Yury Norov wrote:
> On Tue, Jan 25, 2022 at 1:28 AM Tvrtko Ursulin
> <tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote:
> > On 23/01/2022 18:38, Yury Norov wrote:
> > > i915_pmu_cpu_online() calls cpumask_weight() to check if any bit of a
> > > given cpumask is set. We can do it more efficiently with cpumask_empty()
> > > because cpumask_empty() stops traversing the cpumask as soon as it finds
> > > first set bit, while cpumask_weight() counts all bits unconditionally.
> > >
> > > Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
> > > ---
> > >    drivers/gpu/drm/i915/i915_pmu.c | 2 +-
> > >    1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> > > index ea655161793e..1894c876b31d 100644
> > > --- a/drivers/gpu/drm/i915/i915_pmu.c
> > > +++ b/drivers/gpu/drm/i915/i915_pmu.c
> > > @@ -1048,7 +1048,7 @@ static int i915_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)
> > >        GEM_BUG_ON(!pmu->base.event_init);
> > >
> > >        /* Select the first online CPU as a designated reader. */
> > > -     if (!cpumask_weight(&i915_pmu_cpumask))
> > > +     if (cpumask_empty(&i915_pmu_cpumask))
> > >                cpumask_set_cpu(cpu, &i915_pmu_cpumask);
> > >
> > >        return 0;
> >
> > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
> >
> > I see it's a large series which only partially appeared on our mailing
> > lists.
>
> The series is here: https://lkml.org/lkml/2022/1/23/223
> The branch: https://github.com/norov/linux/tree/bitmap-20220123
>
> > So for instance it hasn't got tested by our automated CI. (Not
> > that I expect any problems in this patch.)
>
> Would be great if you give a test for the whole series, thanks!

Can't really test the whole series for you, but if you want to send just 
the i915 patch standalone to the intel-gfx mailing list, that would 
trigger the CI run and if that passes we can merge that single one.

> > What are the plans in terms of which tree will it get merged through?
>
> For the patches that will not be merged by maintainers of corresponding
> subsystems, I'll use my bitmap branch and send it to linux-next.

Or I guess we can wait for them to trickle back to us this way.

Regards,

Tvrtko