Re: Subject: [PATCH] arm/kernel/head.S: optimize __create_page_tables function

From: Russell King - ARM Linux admin
Date: Mon Feb 24 2020 - 07:03:15 EST


Hi,

On Mon, Feb 24, 2020 at 07:54:07PM +0800, yifeng wu wrote:
> Thank you very much for your reply.
> I have tested on my machine. It takes about 0.5 seconds to copy the memory
> (16M size) with "str" instruction, and only 0.1 seconds with "stmia"

ITYM 16k. You say "copy" but we're setting memory to zero. I'm quite
surprised by that difference, which CPU was this measured on?

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