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Message-ID: <5030bcfd-3931-d8e8-4eaa-7a3127cbd6ad@amd.com>
Date:   Mon, 4 Apr 2022 14:22:45 -0500
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Subject: Re: [PATCH v2 1/3] mm: add vm_normal_lru_pages for LRU handled pages
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Content-Language: en-US
To:     Jason Gunthorpe <jgg@nvidia.com>,
        Felix Kuehling <felix.kuehling@amd.com>
Cc:     Christoph Hellwig <hch@lst.de>, david@redhat.com,
        linux-mm@kvack.org, rcampbell@nvidia.com,
        linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org,
        amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        jglisse@redhat.com, apopple@nvidia.com, willy@infradead.org,
        akpm@linux-foundation.org
References: <20220330212537.12186-1-alex.sierra@amd.com>
 <20220330212537.12186-2-alex.sierra@amd.com> <20220331085341.GA22102@lst.de>
 <82ed845d-2534-490c-f9b9-a875e0283cc9@amd.com>
 <20220404173858.GQ2120790@nvidia.com>
From:   "Sierra Guiza, Alejandro (Alex)" <alex.sierra@amd.com>
In-Reply-To: <20220404173858.GQ2120790@nvidia.com>
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On 4/4/2022 12:38 PM, Jason Gunthorpe wrote:
> On Fri, Apr 01, 2022 at 04:08:35PM -0400, Felix Kuehling wrote:
>
>>> In general I find the vm_normal_lru_page vs vm_normal_page
>>> API highly confusing.  An explicit check for zone device pages
>>> in the dozen or so spots that care has a much better documentation
>>> value, especially if accompanied by comments where it isn't entirely
>>> obvious.
>> OK. We can do that. It would solve the function naming problem, and we'd
>> have more visibility of device page handling in more places in the kernel,
>> which has educational value.
> Personally I find the 'is page XYZ' pretty confusing, like I don't
> know half of what the PageKsm annotations are for..
>
> Testing against a specific property the code goes on to use right away
> seems more descriptive to me.

Hi Jason,

Are you referring to test for properties such as is_lru_page, 
is_numa_page, is_lockable_page, etc?
Otherwise, could you provide an example?

Regards,
Alex Sierra

>
> Jason