From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [RFC] create a single workqueue for each vm to update vm irq
 routing table
Date: Tue, 26 Nov 2013 14:13:25 +0100
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Cc: "Zhanghaoyu (A)" <haoyu.zhang@huawei.com>,
	KVM <kvm@vger.kernel.org>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Eric Blake <eblake@redhat.com>,
	Luonengjun <luonengjun@huawei.com>,
	"Huangweidong (C)" <weidong.huang@huawei.com>,
	"Jinxin (F)" <jinxin712@huawei.com>,
	Zanghongyong <zanghongyong@huawei.com>
To: Gleb Natapov <gleb@redhat.com>
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Il 26/11/2013 13:56, Gleb Natapov ha scritto:
> > I don't think a workqueue is even needed.  You just need to use call_rcu
> > to free "old" after releasing kvm->irq_lock.
> > 
> > What do you think?
> 
> It should be rate limited somehow. Since it guest triggarable guest may cause
> host to allocate a lot of memory this way.

True, though if I understand Zhanghaoyu's proposal a workqueue would be
even worse.

Paolo