Re: [v4][PATCH 11/19] tools: introduce some new parameters to set rdm policy

From: "Jan Beulich" <JBeulich@suse.com>
To: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>,
	Ian Campbell <ian.campbell@citrix.com>,
	Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
	IanJackson <ian.jackson@eu.citrix.com>,
	"xen-devel@lists.xen.org" <xen-devel@lists.xen.org>,
	Tiejun Chen <tiejun.chen@intel.com>
Subject: Re: [v4][PATCH 11/19] tools: introduce some new parameters to set rdm policy
Date: Mon, 06 Jul 2015 15:34:42 +0100	[thread overview]
Message-ID: <559AAE22020000780008CC97@mail.emea.novell.com> (raw)
In-Reply-To: <559A90AF.9010407@eu.citrix.com>

>>> On 06.07.15 at 16:29, <george.dunlap@eu.citrix.com> wrote:
> It sounds like part of the problem here is a matter of domains.
> 
> Jan cares mostly about what happens in the hypervisor.  At the
> hypervisor level, there is only the per-device configurations, and he is
> keen that rmrrs be "strict" by default, unless there is an explicit flag
> to relax it.  (I agree with this, FWIW.)
> 
> What we've been arguing about is the xl layer -- what settings should
> xl/libxl give to the hypervisor, based on what's in the domain config?
> 
> It sounds like Jan doesn't care a great deal about it, and in any case
> would defer to the tools maintainers, but that if asked for his advice
> he would say that the configuration in xl.cfg should act like all the
> other pci device configurations: that you have a domain-wide default
> that can be overridden in the per-device setting.
> 
> I.e.:
> ---
> rdm='reserve=strict'
> pci=[ '02:0.0', '01:1.1,rdm_reserve=relaxed' ]
> ---
> Would pass "strict" for the first device, and "relaxed" for the second.
> 
> Do I understand you both properly, Jan / Tiejun?

Yes for me.

Jan