Subject: Re: [PATCH 1/2] powerpc: Use cpumask_next_wrap instead

From: Yury Norov <[email-masked]>
Date: Sat, 28 Mar 2026 16:44:21 -0400

On Fri, Mar 27, 2026 at 12:01:28PM +0530, Shrikanth Hegde wrote:
> cpu = cpumask_next(cpu, mask)
> if (cpu >= nr_cpu_ids)
>     cpu = cpumask_first(mask)
> 
> Above block is identical to:
> cpu = cpumask_next_wrap(cpu, mask)
> 
> Replace it, No change in functionality or performance.
> Slightly simpler code.
> 
> Signed-off-by: Shrikanth Hegde <[email-masked]>
> ---
>  arch/powerpc/kernel/irq.c             | 5 +----
>  arch/powerpc/mm/book3s64/hash_utils.c | 4 +---
>  arch/powerpc/sysdev/xive/common.c     | 5 +----
>  3 files changed, 3 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
> index a0e8b998c9b5..f69de08ad347 100644
> --- a/arch/powerpc/kernel/irq.c
> +++ b/arch/powerpc/kernel/irq.c
> @@ -370,10 +370,7 @@ int irq_choose_cpu(const struct cpumask *mask)
>  do_round_robin:
>  		raw_spin_lock_irqsave(&irq_rover_lock, flags);
>  
> -		irq_rover = cpumask_next(irq_rover, cpu_online_mask);
> -		if (irq_rover >= nr_cpu_ids)
> -			irq_rover = cpumask_first(cpu_online_mask);
> -
> +		irq_rover = cpumask_next_wrap(irq_rover, cpu_online_mask);
>  		cpuid = irq_rover;
>  
>  		raw_spin_unlock_irqrestore(&irq_rover_lock, flags);
> diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
> index 9dc5889d6ecb..e4fcf929cb33 100644
> --- a/arch/powerpc/mm/book3s64/hash_utils.c
> +++ b/arch/powerpc/mm/book3s64/hash_utils.c
> @@ -1299,9 +1299,7 @@ static void stress_hpt_timer_fn(struct timer_list *timer)
>  	if (!firmware_has_feature(FW_FEATURE_LPAR))
>  		tlbiel_all();
>  
> -	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
> -	if (next_cpu >= nr_cpu_ids)
> -		next_cpu = cpumask_first(cpu_online_mask);
> +	next_cpu = cpumask_next_wrap(raw_smp_processor_id(), cpu_online_mask);
>  	stress_hpt_timer.expires = jiffies + msecs_to_jiffies(10);
>  	add_timer_on(&stress_hpt_timer, next_cpu);
>  }
> diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
> index e1a4f8a97393..b6446abe29a6 100644
> --- a/arch/powerpc/sysdev/xive/common.c
> +++ b/arch/powerpc/sysdev/xive/common.c
> @@ -577,10 +577,7 @@ static int xive_find_target_in_mask(const struct cpumask *mask,
>  		 */
>  		if (cpu_online(cpu) && xive_try_pick_target(cpu))
>  			return cpu;
> -		cpu = cpumask_next(cpu, mask);
> -		/* Wrap around */
> -		if (cpu >= nr_cpu_ids)
> -			cpu = cpumask_first(mask);
> +		cpu = cpumask_next_wrap(cpu, mask);

Again, for all except this:

Reviewed-by: Yury Norov <[email-masked]>

Can you move my series for xive_find_target_in_mask() together with
your patches?

>  	} while (cpu != first);
>  	return -1;
> -- 
> 2.47.3