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Date: Thu, 22 Jan 2015 19:23:49 +0900
From: Tetsuya Mukawa <mukawa@igel.co.jp>
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To: Linhaifeng <haifeng.lin@huawei.com>
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] some questions about  rte_memcpy
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On 2015/01/22 16:35, Matthew Hall wrote:
> On Thu, Jan 22, 2015 at 01:32:04PM +0800, Linhaifeng wrote:
>> Do you mean if call rte_memcpy before rte_eal_init() would crash?why?
> No guarantee. But a theory. It might use some things from the EAL init =
to=20
> figure out which version of the accelerated algorithm to use.

This selection is done at compile-time.
And if the size is constant, I guess DPDK assumes memcpy is replaced by
inline __builtin_memcpy.
I haven't checked the performance of builtin memcpy, but probably much
faster.

Tetsuya

> Matthew.