Re: [Qemu-devel] [RFC PATCH v2 18/23] qcow2: Delay the COW

[Kevin Wolf]

On Fri, Feb 15, 2013 at 02:36:37PM +0100, Stefan Hajnoczi wrote:
> On Wed, Feb 13, 2013 at 02:22:08PM +0100, Kevin Wolf wrote:
> >      /**
> > +     * true if the request is sleeping in the COW delay and the coroutine 
> > may
> > +     * be reentered in order to cancel the timer.
> > +     */
> > +    bool sleeping;
> 
> Does reentering actually cancel the timer...or does it lead to a
> spurious entry when the timer fires in the future?
> 
> Do we need anything to really delete the timer in case we re-enter and
> terminate the coroutine before the timer fires?

co_sleep_ns() supports this since commit 3ed99025, it cancels and deletes the
timer. Block jobs use the same thing when you cancel them.

Kevin