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Date: Mon, 12 Sep 2016 13:54:24 +0800
From: Peter Xu <peterx@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v3 2/3] memory: generalize
 iommu_ops.notify_started to notifier_add
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To: David Gibson <david@gibson.dropbear.id.au>
Cc: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org, mst@redhat.com, jasowang@redhat.com, vkaplans@redhat.com, alex.williamson@redhat.com, wexu@redhat.com, cornelia.huck@de.ibm.com, dgibson@redhat.com

On Mon, Sep 12, 2016 at 11:17:37AM +1000, David Gibson wrote:

[...]

> > I think now I understand the point... Then I'd prefer to use David's
> > suggestion. A single notify_changed() looks cleaner. To be more
> > explicit, I would prefer to rename it to notifier_flag_changed(),
> > since notify_changed() looks like to be called every time notifier
> > list changed, but actually it is for monitoring the flags.
> 
> That sounds reasonable.  I think notifier_flag_changed() should be
> passed both the old and new flags, to save the backend having to keep
> track of the old ones - which flags have changed might affect what the
> callback needs to do.

Agree. That's exactly what v4 was doing. Thanks,

-- peterx