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Date: Thu, 02 May 2013 18:58:24 +0200
From: Jan Kiszka <jan.kiszka@siemens.com>
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Subject: Re: [Qemu-devel] [PATCH v7 0/7] push mmio dispatch out of big lock
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To: liu ping fan <qemulist@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, "gleb@redhat.com" <gleb@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, Marcelo Tosatti <mtosatti@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Anthony Liguori <anthony@codemonkey.ws>, Paolo Bonzini <pbonzini@redhat.com>

Hi Pingfan,

On 2012-12-06 08:28, liu ping fan wrote:
> Any suggestion? Or new design idea for this?

Finally... I'm getting back to this. I'm currently trying to make use of
this series, adapting it to my needs (selective BQL-free dispatching of
PIO regions).

Is there a newer version available on your side? This one obviously no
longer applies due to all the code movements in QEMU. But it also seems
to contain some bugs, at least in patch 5 (mixed up page number vs. page
address around for address_space_section_lookup_ref).

Then we should get rid of the ref/unref callbacks. Making a memory
region BQL-free must be as simple as setting a flag or (more likely)
adding a reference to the owning QOM object in the region.
Reimplementing ref/unref in device models over and over again is clearly
a no-go. Maybe I'm currently forgetting a use case where overloading the
reference functions is needed, so please help my memory in that case.

Jan

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