From mboxrd@z Thu Jan  1 00:00:00 1970
From: George Dunlap <george.dunlap@eu.citrix.com>
Subject: Re: [PATCH v2 11/16] libxc: get and set soft and hard
	affinity
Date: Thu, 14 Nov 2013 15:38:09 +0000
Message-ID: <5284EE61.5000707@eu.citrix.com>
References: <20131113190852.18086.5437.stgit@Solace>
	<20131113191242.18086.73258.stgit@Solace>
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To: Dario Faggioli <dario.faggioli@citrix.com>, xen-devel@lists.xen.org
Cc: Marcus Granado <Marcus.Granado@eu.citrix.com>, Keir Fraser <keir@xen.org>, Ian Campbell <Ian.Campbell@citrix.com>, Li Yechen <lccycc123@gmail.com>, Andrew Cooper <Andrew.Cooper3@citrix.com>, Juergen Gross <juergen.gross@ts.fujitsu.com>, Ian Jackson <Ian.Jackson@eu.citrix.com>, Jan Beulich <JBeulich@suse.com>, Justin Weaver <jtweaver@hawaii.edu>, Matt Wilson <msw@amazon.com>, Elena Ufimtseva <ufimtseva@gmail.com>
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On 13/11/13 19:12, Dario Faggioli wrote:
> by using the new flag introduced in the parameters of
> DOMCTL_{get,set}_vcpuaffinity.
>
> This happens in two new xc calls: xc_vcpu_setaffinity_hard()
> and xc_vcpu_setaffinity_soft() (an in the corresponding
> getters, of course).

Personally I think:
* You should be able to set both HARD and SOFT flags, in which case it 
will set both hard and soft affinities
* You should expose the "flags" to the xc caller, so that the caller can 
set either one or both.

>
> The existing xc_vcpu_{set,get}affinity() call is also retained,
> with the following behavior:
>
>   * xc_vcpu_setaffinity() sets both the hard and soft affinity;
>   * xc_vcpu_getaffinity() gets the hard affinity.
>
> This is mainly for backward compatibility reasons, i.e., trying
> not to break existing callers/users.

The xc interface isn't stable, right?  Couldn't we just change the 
callers (presumably just xend and libxl)?

  -George