linux-kernel - Re: [PATCH v2 1/2] percpu: Add percpu_counter_add

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

Message-ID: <4a6937b9-08b1-0f52-18db-13e17e344786@intel.com>
Date:   Tue, 6 Sep 2022 16:41:55 +0800
From:   "Sun, Jiebin" <jiebin.sun@...el.com>
To:     Shakeel Butt <shakeelb@...gle.com>
Cc:     akpm@...ux-foundation.org, vasily.averin@...ux.dev,
        dennis@...nel.org, tj@...nel.org, cl@...ux.com,
        ebiederm@...ssion.com, legion@...nel.org, manfred@...orfullife.com,
        alexander.mikhalitsyn@...tuozzo.com, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, tim.c.chen@...el.com,
        feng.tang@...el.com, ying.huang@...el.com, tianyou.li@...el.com,
        wangyang.guo@...el.com, jiebin.sun@...el.com
Subject: Re: [PATCH v2 1/2] percpu: Add percpu_counter_add_local


On 9/6/2022 3:31 AM, Shakeel Butt wrote:
> On Tue, Sep 06, 2022 at 03:35:16AM +0800, Jiebin Sun wrote:
>> Add percpu_counter_add_local for only updating local counter
>> without aggregating to global counter.
> Please add why do we need this. Who should use this and who shouldn't.

Thanks. I have added the code comment and change log in patch v3 and 
provided

the info who should use it and who shouldn't.

>
>> Signed-off-by: Jiebin Sun <jiebin.sun@...el.com>
> [...]
>
>> diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
>> index ed610b75dc32..d33cb750962a 100644
>> --- a/lib/percpu_counter.c
>> +++ b/lib/percpu_counter.c
>> @@ -72,6 +72,12 @@ void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
>>   }
>>   EXPORT_SYMBOL(percpu_counter_set);
>>
> Add a doc comment here on why someone want to use this?
>
>> +void percpu_counter_add_local(struct percpu_counter *fbc, s64 amount)
>> +{
>> +	this_cpu_add(*fbc->counters, amount);
>> +}
>> +EXPORT_SYMBOL(percpu_counter_add_local);
>> +
>>   /*
>>    * This function is both preempt and irq safe. The former is due to explicit
>>    * preemption disable. The latter is guaranteed by the fact that the slow path
>> -- 
>> 2.31.1
>>