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Date: Tue, 10 May 2016 17:54:31 +0800
From: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH] rfifolock: no need to get thread
 identifier when nesting
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To: "Denis V. Lunev" <den-lists@virtuozzo.com>, qemu devel <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

On 05/10/2016 05:38 PM, Denis V. Lunev wrote:
> On 05/10/2016 12:16 PM, Changlong Xie wrote:
>> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
>> ---
>>   util/rfifolock.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/util/rfifolock.c b/util/rfifolock.c
>> index c22f5fe..f406cc1 100644
>> --- a/util/rfifolock.c
>> +++ b/util/rfifolock.c
>> @@ -50,6 +50,7 @@ void rfifolock_lock(RFifoLock *r)
>>       if (r->nesting > 0 && qemu_thread_is_self(&r->owner_thread)) {
>>           r->tail--; /* put ticket back, we're nesting */
>> +        goto out;
>>       } else {
>>           while (ticket != r->head) {
>>               /* Invoke optional contention callback */
>> @@ -61,6 +62,7 @@ void rfifolock_lock(RFifoLock *r)
>>       }
>>       qemu_thread_get_self(&r->owner_thread);
>> +out:
>>       r->nesting++;
>>       qemu_mutex_unlock(&r->lock);
>>   }
> it would be better to put
>      qemu_thread_get_self(&r->owner_thread);
> 2 lines up and avoid unnecessary goto

Yes, it's a better choice, will send out v2

Thanks
	-Xie
>
>
>