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Date: Wed, 27 Mar 2024 14:56:31 +0100
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Subject: Re: [PATCH RFC 1/3] mm/gup: consistently name GUP-fast functions
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To: Jason Gunthorpe <jgg@nvidia.com>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
 Mike Rapoport <rppt@kernel.org>, John Hubbard <jhubbard@nvidia.com>,
 Peter Xu <peterx@redhat.com>, linux-arm-kernel@lists.infradead.org,
 loongarch@lists.linux.dev, linux-mips@vger.kernel.org,
 linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
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References: <20240327130538.680256-1-david@redhat.com>
 <20240327130538.680256-2-david@redhat.com>
 <20240327135256.GG946323@nvidia.com>
From: David Hildenbrand <david@redhat.com>
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Organization: Red Hat
In-Reply-To: <20240327135256.GG946323@nvidia.com>
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On 27.03.24 14:52, Jason Gunthorpe wrote:
> On Wed, Mar 27, 2024 at 02:05:36PM +0100, David Hildenbrand wrote:
>> Let's consistently call the "fast-only" part of GUP "GUP-fast" and rename
>> all relevant internal functions to start with "gup_fast", to make it
>> clearer that this is not ordinary GUP. The current mixture of
>> "lockless", "gup" and "gup_fast" is confusing.
>>
>> Further, avoid the term "huge" when talking about a "leaf" -- for
>> example, we nowadays check pmd_leaf() because pmd_huge() is gone. For the
>> "hugepd"/"hugepte" stuff, it's part of the name ("is_hugepd"), so that
>> says.
>>
>> What remains is the "external" interface:
>> * get_user_pages_fast_only()
>> * get_user_pages_fast()
>> * pin_user_pages_fast()
>>
>> And the "internal" interface that handles GUP-fast + fallback:
>> * internal_get_user_pages_fast()
> 
> This would like a better name too. How about gup_fast_fallback() ?

Yes, I was not able to come up with something I liked. But I do like
your proposal, so I'll do that!

[...]

> 
> I think it is a great idea, it always takes a moment to figure out if
> a function is part of the fast callchain or not..
> 
> (even better would be to shift the fast stuff into its own file, but I
> expect that is too much)

Yes, one step at a time :)

> 
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Thanks Jason!

-- 
Cheers,

David / dhildenb