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Date: Tue, 23 Oct 2012 13:55:44 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [patch v4 05/16] memory: introduce ref,
	unref interface for MemoryRegionOps
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Liu Ping Fan <pingfank@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@gmail.com>, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Anthony Liguori <anthony@codemonkey.ws>, Jan Kiszka <jan.kiszka@siemens.com>

On 10/23/2012 01:51 PM, Paolo Bonzini wrote:
> Il 22/10/2012 11:38, Avi Kivity ha scritto:
>>> >  
>>> >  typedef struct MemoryRegionOps MemoryRegionOps;
>>> >  typedef struct MemoryRegion MemoryRegion;
>>> > @@ -66,6 +67,8 @@ struct MemoryRegionOps {
>>> >                    target_phys_addr_t addr,
>>> >                    uint64_t data,
>>> >                    unsigned size);
>>> > +    int (*ref)(MemoryRegion *mr);
>>> > +    void (*unref)(MemoryRegion *mr);
>>> >  
>> Why return an int?  Should succeed unconditionally.  Please fold into 7
>> (along with 6).
> 
> So the stop_machine idea is thrown away?  

IIRC I convinced myself that it's just as bad.

> I really believe we're going
> down a rat's nest with reference counting.

There will be a lot of teething problems, but the same ideas are used
extensively in the kernel.

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