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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri, 15 Oct 2010 16:42:27 +0200
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Subject: [Qemu-devel] Re: [PATCH 1/3] Introduce threadlets
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To: qemu-devel@nongnu.org
Cc: Arun R Bharadwaj <arun@linux.vnet.ibm.com>

On 10/14/2010 11:02 AM, Stefan Hajnoczi wrote:
> 2. Moving qemu_cond_signal() outside queue->lock is dangerous for the
> same reason: you need to be careful not to qemu_cond_signal() when the
> thread isn't inside qemu_cond_timedwait()."

Yes, please do so.

I personally consider it bad programming practice to put the condvar 
signal/broadcast outside the mutex.  While I understand that my ideas 
may not matter much, some Mr. Hoare actually invented them without 
signal-outside-lock, and he probably knows better than anyone reading.

Paolo