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Date: Sat, 24 Feb 2007 03:56:34 -0600
From: "V P" <upathiyayan@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: REQ_HARDBARRIER and REQ_SOFTBARRIER
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Hi,

I'm trying to modify the ordering of I/O requests in Linux kernel, and
came across the barrier flags REQ_HARDBARRIER and REQ_SOFTBARRIER.

One thing I noticed (which might be wrong) is that all the requests
have both these flags set. What is the significance of these flags? Is
it a must for a request to have this? Can I reorder two requests with
these flags set? How is SOFTBARRIER different from HARDBARRIER?

I appreciate your time and help.

Thanks much.