From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juergen Gross <jgross@suse.com>
Subject: Re: [PATCH v3 3/6] xen: sched: clarify use cases of
 schedule_cpu_switch()
Date: Fri, 30 Oct 2015 05:33:47 +0100
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To: Dario Faggioli <dario.faggioli@citrix.com>
Cc: George Dunlap <george.dunlap@eu.citrix.com>, "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>, Jan Beulich <JBeulich@suse.com>
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On 10/30/2015 12:59 AM, Dario Faggioli wrote:
> On Fri, 2015-10-30 at 00:04 +0100, Dario Faggioli wrote:
>> schedule_cpu_switch() is meant to be only used for moving
>> pCPUs from a cpupool to no cpupool, and from there back
>> to a cpupool, *not* to move them directly from one cpupool
>> to another.
>>
>> This is something that is reflected in the way it is
>> implemented, and should be kept in mind when looking at
>> it. However, that is not that clear, by just the look of
>> it.
>>
>> Make it more evident by:
>>   - adding commentary and ASSERT()s;
>>   - update the cpupool per-CPU variable (mapping pCPUs to
>>     pools) directly in schedule_cpu_switch(), rather than
>>     in various places in cpupool.c.
>>
>> Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
>> Acked-by: Juergen Gross <jgross@suse.com>
>>
> BTW, Juergen, I had the whole series tested with the script below, for
> a few hourse, as per your suggestion to help confirming that this patch
> is actually correct, as it seems by just looking at the code.
>
> Since everything was fine, I added your Ack, as you said I could.

Great. Thanks for doing this!

BTW: I especially like that you removed cpu 0 from Pool-0!


Juergen