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Subject: Re: [Qemu-devel] [PATCH v7 1/7] qom: apply atomic on object's
	refcount
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To: Liu Ping Fan <qemulist@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, gleb@redhat.com, Jan Kiszka <jan.kiszka@siemens.com>, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Anthony Liguori <anthony@codemonkey.ws>, Stefan Hajnoczi <stefanha@gmail.com>, Paolo Bonzini <pbonzini@redhat.com>

On 11/24/2012 06:02 PM, Liu Ping Fan wrote:
> -    obj->ref--;
>  
>      /* parent always holds a reference to its children */
> -    if (obj->ref == 0) {
> +    if (__sync_fetch_and_sub(&obj->ref, 1) == 1) {

  if (__sync_sub_and_fetch(&obj->ref, 1) == 0)


r~