From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] kvm: First step to push iothread lock out of inner run
 loop
Date: Wed, 27 Jun 2012 10:54:59 +0300
Message-ID: <4FEABC53.6040007@redhat.com>
References: <4FE4F56D.1020201@web.de> <4FE4F7F5.7030400@web.de> <20120626193420.GA19852@amt.cnet>
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Cc: Jan Kiszka <jan.kiszka@web.de>, qemu-devel <qemu-devel@nongnu.org>,
	Liu Ping Fan <pingfank@linux.vnet.ibm.com>,
	Alexander Graf <agraf@suse.de>,
	Anthony Liguori <anthony@codemonkey.ws>,
	kvm <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 06/26/2012 10:34 PM, Marcelo Tosatti wrote:
> 
> 1.  read_lock(memmap_lock)
> 2.  MemoryRegionSection mrs = lookup(addr)
> 3.  qom_ref(mrs.mr->dev)
> 4.  read_unlock(memmap_lock)
> 
> 5.  mutex_lock(dev->lock)
> 6.  dispatch(&mrs, addr, data, size)
> 7.  mutex_unlock(dev->lock)
> 
> 8.  qom_unref(mrs.mr->object)

The plan also includes eventually replacing read_lock() with rcu; so two
devices can be accessed in parallel with no cacheline bouncing.

-- 
error compiling committee.c: too many arguments to function