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Subject: Re: [PATCH liburing v1 7/9] arch/arm64: Add `get_page_size()`
 function
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To:     Jens Axboe <axboe@kernel.dk>
Cc:     Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>,
        Fernanda Ma'rouf <fernandafmr12@gnuweeb.org>,
        Pavel Begunkov <asml.silence@gmail.com>,
        Hao Xu <howeyxu@tencent.com>,
        io-uring Mailing List <io-uring@vger.kernel.org>,
        GNU/Weeb Mailing List <gwml@gnuweeb.org>
References: <20220629002028.1232579-1-ammar.faizi@intel.com>
 <20220629002028.1232579-8-ammar.faizi@intel.com>
 <8bfba71c-55d7-fb49-6593-4d0f9d9c3611@kernel.dk>
From:   Ammar Faizi <ammarfaizi2@gnuweeb.org>
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On 6/29/22 9:49 PM, Jens Axboe wrote:
> On 6/28/22 6:27 PM, Ammar Faizi wrote:
>> From: Ammar Faizi <ammarfaizi2@gnuweeb.org>
>>
>> This is a preparation patch to add aarch64 nolibc support.
>>
>> aarch64 supports three values of page size: 4K, 16K, and 64K which are
>> selected at kernel compilation time. Therefore, we can't hard code the
>> page size for this arch. Utilize open(), read() and close() syscall to
>> find the page size from /proc/self/auxv. For more details about the
>> auxv data structure, check the link below.
> 
> We should probably cache this value if already read? At least I don't
> think we have systems where the page size would differ between
> applications.

Good idea, will use a static variable to cache it in v2 then...

-- 
Ammar Faizi