[libvirt] PATCH: 14/28: Thread safety for network driver

[Daniel Veillard]

On Wed, Dec 03, 2008 at 09:44:50AM +0000, Daniel P. Berrange wrote:
> On Wed, Dec 03, 2008 at 10:32:58AM +0100, Daniel Veillard wrote:
> > On Sun, Nov 30, 2008 at 11:55:51PM +0000, Daniel P. Berrange wrote:
> > > This patch makes the network driver thread safe, following the pattern of
> > > the earlier patches
> > 
> > > @@ -95,6 +107,7 @@ networkAutostartConfigs(struct network_d
> > >      unsigned int i;
> > 
> >   Hum, you're not locking the driver itself during the loop ?
> > If a concurrent call were to remove one of the network object in
> > the meantime, that would lead to potentially random memory accesses
> > no ?
> 
> There are only two callers of this method, and they both already hold the
> driver lock - networkStartup() and networkReload().

  I realized that when digging more in the storage case... see next mail
  :-)

> > >  cleanup:
> > > +    if (network)
> > > +        virNetworkObjUnlock(network);
> > 
> >   like for domain, I would suggest the unlocking accessor to accept NULL
> > and drop all the if constructs
> 
> I've thought about doing that, but wasn't really sure whether it was good
> idea or not. I thought it might hide bugs, but on balance it would certainly
> simplify alot of code. If people generally think its worth allowing NULL
> in the Unlock routine, i'll make it so.

  well we did a similar change for freeing ...

Daniel

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