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Date: Tue, 25 Jun 2013 08:24:28 +0200
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Subject: Re: [Qemu-devel] [PATCH 0/3] make bh safe with hot-unplug
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To: Liu Ping Fan <qemulist@gmail.com>
Cc: qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>

Il 25/06/2013 19:38, Liu Ping Fan ha scritto:
> This series relies on refcnt of object used by bh callback to run against unplug.
> 
> Open issue:
> Another choice may be rcu, but I think some issues are hard to resolve.
> Using rcu, we have two choice:
>   when holding object refcnt, call qemu_bh_delete(); then after grace period, we can release.
>   Or making qemu_bh_delete() sync in the path of DeviceState's finalization.

What do you mean exactly?  qemu_bh_delete() is async, but it operates on
dynamically-allocated memory.

Paolo

> but currently, the callers of qemu_bh_delete() can not satisfy any of the two condition.