Re: [Qemu-devel] [PATCH v2 1/4] block: extract AIO_WAIT_WHILE() from BlockDriverState

[Eric Blake]

On 02/13/2018 10:01 AM, Eric Blake wrote:
> On 02/13/2018 08:20 AM, Stefan Hajnoczi wrote:
> > BlockDriverState has the BDRV_POLL_WHILE() macro to wait on event loop
> > activity while a condition evaluates to true.  This is used to implement
> > synchronous operations where it acts as a condvar between the IOThread
> > running the operation and the main loop waiting for the operation.  It
> > can also be called from the thread that owns the AioContext and in that
> > case it's just a nested event loop.

> It may be that your patch is correct (as I'm not an expert on the rules 
> in play here), but more comments may help.  Or you may have a NULL 
> dereference bug lurking.  So at this point, I can't give R-b, even 
> though the refactoring of the BDRV_POLL_WHILE() macro into a separate 
> helper makes sense from the high level view.

Okay, based on your responses, I can now give

Reviewed-by: Eric Blake <address@hidden>

although it may still help to do followups with better documentation 
and/or a rename of the confusing functions.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org