[Intel-gfx] [PATCH 1/2] drm/i915/pmu: Limit the selection of the dedicated reader cpu to an online sibling

[Tvrtko Ursulin]

On 22/11/2017 18:26, Chris Wilson wrote:
> When bringing a cpu online, we want to see if it or a sibling is already
> in the online mask before adding to the designated reader.
> 
> Fixes: b46a33e271ed ("drm/i915/pmu: Expose a PMU interface for perf queries")
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Dmitry Rogozhkin <dmitry.v.rogozhkin at intel.com>
> ---
>   drivers/gpu/drm/i915/i915_pmu.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 1071935bfa67..64e36d72e76a 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -750,7 +750,8 @@ static int i915_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)
>   
>   	GEM_BUG_ON(!pmu->base.event_init);
>   
> -	target = cpumask_any_and(&i915_pmu_cpumask, &i915_pmu_cpumask);
> +	target = cpumask_any_and(&i915_pmu_cpumask,
> +				 topology_sibling_cpumask(cpu));
>   	/* Select the first online CPU as a designated reader. */
>   	if (target >= nr_cpu_ids)
>   		cpumask_set_cpu(cpu, &i915_pmu_cpumask);
>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Regards,

Tvrtko