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Date: Tue, 19 Oct 2010 21:29:59 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] Re: [PATCH 1/3] Introduce threadlets
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To: balbir@linux.vnet.ibm.com
Cc: Arun R Bharadwaj <arun@linux.vnet.ibm.com>, qemu-devel@nongnu.org

On 10/19/2010 09:12 PM, Balbir Singh wrote:
> > >Ideally you need
> > >
> > >           s = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
> > >
> > > But qemu will need to wrap this around as well.
> >
> >  Why?  QEMU is never using thread cancellation.
>
> Yes, I agree, in the longer run, cancellation is a good way to kill
> threads, specially in a thread pool. My comment was more along the
> lines of good practices and potential use of pthread_cancel(), not a
> strict comment on something urgent or broken.

But there is no such use; as long as we keep ourselves to the 
qemu-thread API, we know that nothing will use cancellation.

The day qemu-thread will introduce cancellation functions we'll care 
about enabling/disabling it in some threads.

Paolo