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Date: Sun, 21 Oct 2012 14:00:04 +0200
From: Richard Cochran <richardcochran@gmail.com>
To: caiyuqing <yuqingcaik@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: question about context switch on arm Linux
Message-ID: <20121021120003.GA8689@netboy.at.omicron.at>
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On Sun, Oct 21, 2012 at 04:19:50PM +0800, caiyuqing wrote:
> Richard, thanks for your reply.
> mainline Linux doesn't support FCSE, if so, when kernel switch a
> process to another(these two process share the same virtual memory
> space), that means the vitrual-to-physical address should be
> remaped, TLB shuold be invalid, CACHE should be flushed, right?

Yes, and that is why you can measure quite a long context switching
time when running Linux on ARMv4/5.

Thanks,
Richard