linux-kernel - Re: [PATCH] sched/deadline: simplify dl_bw_cpus() using cpumask_weight

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <1d5e80c1-69e6-e2e8-a5d1-6117cb661013@huawei.com>
Date:   Wed, 14 Jun 2023 09:43:49 +0800
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     Phil Auld <pauld@...hat.com>, <bristot@...hat.com>,
        <vschneid@...hat.com>, <dietmar.eggemann@....com>,
        <quic_mojha@...cinc.com>
CC:     <mingo@...hat.com>, <peterz@...radead.org>,
        <juri.lelli@...hat.com>, <vincent.guittot@...aro.org>,
        <dietmar.eggemann@....com>, <rostedt@...dmis.org>,
        <bsegall@...gle.com>, <mgorman@...e.de>, <bristot@...hat.com>,
        <vschneid@...hat.com>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] sched/deadline: simplify dl_bw_cpus() using
 cpumask_weight_and()

On 2023/6/13 21:16, Phil Auld wrote:
> On Tue, Jun 13, 2023 at 08:19:22PM +0800 Miaohe Lin wrote:
>> On 2023/5/22 19:56, 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@...wei.com>
>>
>> friendly ping... :)
> 
> This looks reasonable, and better, to me.
> 
> Reviewed-by: Phil Auld <pauld@...hat.com>

Many thanks for all of your reviews. :)

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