From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Anderson <andmike@linux.vnet.ibm.com>
Subject: Re: [PATCH 0/2] Add suspended state check for target
	messages
Date: Sun, 15 Nov 2009 23:43:33 -0800
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Kiyoshi Ueda <k-ueda@ct.jp.nec.com> wrote:
> Hi Alasdair,
> 
> On 11/13/2009 11:19 PM +0900, Alasdair G Kergon wrote:
> > Would DMF_BLOCK_IO_FOR_SUSPEND work instead?
> 
> Maybe.
> But we must remember that using the flag means that multipath can't
> use message during flushing I/Os, although I'm not sure how it hurts us.
> 
> If we'd like to keep the ability to use message during flushing I/Os,
> we should use another flag for this purpose and set it after
> dm_wait_for_completion().
> 

I just re-rolled / re-submitted a update series that use a multipath
internal flag for the suspended state plus a mutex. This would avoid a
extended meaning for DMF_BLOCK_IO_FOR_SUSPEND if we needed to avoid that
case.

-andmike
--
Michael Anderson
andmike@linux.vnet.ibm.com