From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH 5/7] xen: sched: get rid of the per domain
 vCPU list in Credit2
Date: Thu, 8 Oct 2015 14:56:56 +0100
Message-ID: <56167628.6050400@citrix.com>
References: <20151008124027.12522.42552.stgit@Solace.station>
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To: Dario Faggioli <dario.faggioli@citrix.com>, xen-devel@lists.xenproject.org
Cc: George Dunlap <george.dunlap@eu.citrix.com>
List-Id: xen-devel@lists.xenproject.org

On 08/10/15 13:53, Dario Faggioli wrote:
> @@ -1443,7 +1433,7 @@ csched2_dom_cntl(
>  
>          if ( op->u.credit2.weight != 0 )
>          {
> -            struct list_head *iter;
> +            struct vcpu *vc;

Any chance of starting to align on the more common practice of just v
for a vcpu?

> @@ -1539,9 +1528,7 @@ csched2_free_domdata(const struct scheduler *ops, void *data)
>  static void
>  csched2_dom_destroy(const struct scheduler *ops, struct domain *dom)
>  {
> -    struct csched2_dom *sdom = CSCHED2_DOM(dom);
> -
> -    BUG_ON(!list_empty(&sdom->vcpu));
> +    BUG_ON(CSCHED2_DOM(dom)->nr_vcpus != 0);

This is a latent bug (excuse the pun) which can be triggered by
userspace.  There is no guarantee or requirement that a domain
registered with a scheduler has vcpus.

~Andrew