From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Subject: Re: [PATCH MINI-OS] xenbus: notify the other end when
	necessary
Date: Mon, 26 Oct 2015 13:21:51 +0100
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To: Wei Liu <wei.liu2@citrix.com>
Cc: minios-devel@lists.xenproject.org, Xen-devel <xen-devel@lists.xenproject.org>, Ian Jackson <ian.jackson@eu.citrix.com>, Ian Campbell <ian.campbell@citrix.com>
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Wei Liu, le Mon 26 Oct 2015 12:14:43 +0000, a =E9crit :
> In my patch, mini-os notifies remote whenever it consumes a message,
> which I think it's slightly better because backend can start putting
> things in the ring as mini-os processes them.

That makes more notifications, but that can lead to more pipelining
indeed.  That's what the Linux driver does, so let's do the same.

Also, I'm realizing: aren't we missing a full memory barrier between
the memcpy_from_ring call and xenstore_buf->rsp_cons +=3D ? (in the two
places) We need to make sure to have finished copying from the ring
before writing the new rsp_cons.

Samuel