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Date: Mon, 03 Jan 2011 10:46:29 +0100
From: Jan Kiszka <jan.kiszka@web.de>
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Subject: [Qemu-devel] Role of qemu_fair_mutex
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm <kvm@vger.kernel.org>

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Hi,

at least in kvm mode, the qemu_fair_mutex seems to have lost its
function of balancing qemu_global_mutex access between the io-thread and
vcpus. It's now only taken by the latter, isn't it?

This and the fact that qemu-kvm does not use this kind of lock made me
wonder what its role is and if it is still relevant in practice. I'd
like to unify the execution models of qemu-kvm and qemu, and this lock
is the most obvious difference (there are surely more subtle ones as
well...).

Jan


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