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From:   xu xin <xu.xin.sc@gmail.com>
To:     david@redhat.com
Cc:     akpm@linux-foundation.org, imbrenda@linux.ibm.com,
        jiang.xuexin@zte.com.cn, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, ran.xiaokai@zte.com.cn, xu.xin.sc@gmail.com,
        xu.xin16@zte.com.cn, yang.yang29@zte.com.cn
Subject: Re: [PATCH v8 1/6] ksm: support unsharing KSM-placed zero pages
Date:   Tue, 23 May 2023 22:11:04 +0800
Message-Id: <20230523141104.7029-1-xu.xin16@zte.com.cn>
In-Reply-To: <4b7e4d48-f0f9-c0b0-e8e1-2678d0306252@redhat.com>
References: <4b7e4d48-f0f9-c0b0-e8e1-2678d0306252@redhat.com>
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>>>> ---
>>>>    include/linux/ksm.h | 6 ++++++
>>>>    mm/ksm.c            | 5 +++--
>>>>    2 files changed, 9 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/include/linux/ksm.h b/include/linux/ksm.h
>>>> index 899a314bc487..7989200cdbb7 100644
>>>> --- a/include/linux/ksm.h
>>>> +++ b/include/linux/ksm.h
>>>> @@ -26,6 +26,9 @@ int ksm_disable(struct mm_struct *mm);
>>>>    
>>>>    int __ksm_enter(struct mm_struct *mm);
>>>>    void __ksm_exit(struct mm_struct *mm);
>>>> +/* use pte_mkdirty to track a KSM-placed zero page */
>>>> +#define set_pte_ksm_zero(pte)    pte_mkdirty(pte_mkspecial(pte))
>>>
>>> If there is only a single user (which I assume), please inline it instead.
>> 
>> Excuse me, I'm wondering why using inline here instead of macro is better.
>> Thanks! :)
>
>Just to clarify: not an inline function but removing the macro 
>completely and just place that code directly into the single caller.
>
>Single user, no need to put that into ksm.h -- and I'm not super happy 
>about the set_pte_ksm_zero() name ;) because we get the zero-pte already 
>passed in from the caller ...

Oh, I see. Thanks