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Subject: Re: [PATCH] net: optimize cmpxchg in ip_idents_reserve
To:     David Miller <davem@davemloft.net>
References: <1579058620-26684-1-git-send-email-zhangshaokun@hisilicon.com>
 <20200116.042722.153124126288244814.davem@davemloft.net>
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From:   Shaokun Zhang <zhangshaokun@hisilicon.com>
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Date:   Thu, 16 Jan 2020 22:05:28 +0800
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Hi David,

On 2020/1/16 20:27, David Miller wrote:
> From: Shaokun Zhang <zhangshaokun@hisilicon.com>
> Date: Wed, 15 Jan 2020 11:23:40 +0800
> 
>> From: Yuqi Jin <jinyuqi@huawei.com>
>>
>> atomic_try_cmpxchg is called instead of atomic_cmpxchg that can reduce
>> the access number of the global variable @p_id in the loop. Let's
>> optimize it for performance.
>>
>> Cc: "David S. Miller" <davem@davemloft.net>
>> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
>> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
>> Cc: Eric Dumazet <edumazet@google.com>
>> Cc: Yang Guo <guoyang2@huawei.com>
>> Signed-off-by: Yuqi Jin <jinyuqi@huawei.com>
>> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
> 
> I doubt this makes any measurable improvement in performance.
> 
> If you can document a specific measurable improvement under
> a useful set of circumstances for real usage, then put those
> details into the commit message and resubmit.

Ok, I will do it and resubmit.

Thanks your reply,
Shaokun

> 
> Otherwise, I'm not applying this, sorry.
> 
> .
>