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Message-ID: <b88e83c2-9712-d07d-b48a-5981169cff0f@quicinc.com>
Date:   Mon, 22 May 2023 16:17:33 +0530
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Subject: Re: [PATCH] sched/deadline: simplify dl_bw_cpus() using
 cpumask_weight_and()
Content-Language: en-US
To:     Miaohe Lin <linmiaohe@huawei.com>, <mingo@redhat.com>,
        <peterz@infradead.org>, <juri.lelli@redhat.com>,
        <vincent.guittot@linaro.org>
CC:     <dietmar.eggemann@arm.com>, <rostedt@goodmis.org>,
        <bsegall@google.com>, <mgorman@suse.de>, <bristot@redhat.com>,
        <vschneid@redhat.com>, <linux-kernel@vger.kernel.org>
References: <20230522115605.1238227-1-linmiaohe@huawei.com>
From:   Mukesh Ojha <quic_mojha@quicinc.com>
In-Reply-To: <20230522115605.1238227-1-linmiaohe@huawei.com>
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On 5/22/2023 5:26 PM, Miaohe Lin wrote:
> cpumask_weight_and() can be used to count of bits both in rd->span and
> cpu_active_mask. No functional change intended.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>   kernel/sched/deadline.c | 11 +----------
>   1 file changed, 1 insertion(+), 10 deletions(-)
> 
> diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
> index 166c3e6eae61..fe983ed7bb12 100644
> --- a/kernel/sched/deadline.c
> +++ b/kernel/sched/deadline.c
> @@ -110,20 +110,11 @@ static inline struct dl_bw *dl_bw_of(int i)
>   static inline int dl_bw_cpus(int i)
>   {
>   	struct root_domain *rd = cpu_rq(i)->rd;
> -	int cpus;
>   
>   	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
>   			 "sched RCU must be held");
>   
> -	if (cpumask_subset(rd->span, cpu_active_mask))
> -		return cpumask_weight(rd->span);
> -
> -	cpus = 0;
> -
> -	for_each_cpu_and(i, rd->span, cpu_active_mask)
> -		cpus++;
> -
> -	return cpus;
> +	return cpumask_weight_and(rd->span, cpu_active_mask);
>   }


Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>

-- Mukesh

>   
>   static inline unsigned long __dl_bw_capacity(const struct cpumask *mask)