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Message-ID: <18fa08bf-847b-1c47-10ee-01c92caeb0cc@bytedance.com>
Date:   Wed, 10 Nov 2021 20:58:35 +0800
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Subject: Re: [PATCH v3 02/15] mm: introduce is_huge_pmd() helper
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     akpm@linux-foundation.org, tglx@linutronix.de,
        kirill.shutemov@linux.intel.com, mika.penttila@nextfour.com,
        david@redhat.com, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        songmuchun@bytedance.com, zhouchengming@bytedance.com
References: <20211110084057.27676-1-zhengqi.arch@bytedance.com>
 <20211110084057.27676-3-zhengqi.arch@bytedance.com>
 <20211110122945.GO1740502@nvidia.com>
From:   Qi Zheng <zhengqi.arch@bytedance.com>
In-Reply-To: <20211110122945.GO1740502@nvidia.com>
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On 11/10/21 8:29 PM, Jason Gunthorpe wrote:
> On Wed, Nov 10, 2021 at 04:40:44PM +0800, Qi Zheng wrote:
>> Currently we have some times the following judgments repeated in the
>> code:
>>
>> 	is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)
>>
>> which is to determine whether the *pmd is a huge pmd, so introduce
>> is_huge_pmd() helper to deduplicate them.
> 
> Isn't this pmd_leaf() ?

Currently, the implementation of pmd_leaf() does not include
pmd_devmap() checks. But considering the semantics of pmd_leaf(),
the "devmap" pmd should also belong to "leaf" pmd. Maybe we should
modify pmd_leaf() to make it more semantically consistent?

By the way, something went wrong when sending this patchset, and
I have re-sent the complete patchset, please comment over there.

Thanks,
Qi

> 
> Jason
>