Re: [Qemu-devel] [PATCH] net: fix vhost-user mingw compilation

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jun 19, 2014 at 05:33:02PM +0300, Nikolay Nikolaev wrote:
> Hello,
> 
> 
> On Thu, Jun 19, 2014 at 5:24 PM, Michael S. Tsirkin <mst@redhat.com> wrote:
> 
>     On Thu, Jun 19, 2014 at 05:16:44PM +0300, Nikolay Nikolaev wrote:
>     > Hello,
>     >
>     >
>     > On Wed, Jun 18, 2014 at 11:45 PM, Nikolay Nikolaev <
>     > n.nikolaev@virtualopensystems.com> wrote:
>     >
>     >     Make net.o linkage expect net_init_vhost_user only when
>     >     CONFIG_VHOST_NET is defined.
>     >
>     >     Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
>     >     ---
>     >      net/net.c |    4 ++++
>     >      1 file changed, 4 insertions(+)
>     >
>     >     diff --git a/net/net.c b/net/net.c
>     >     index de76e30..0c30414 100644
>     >     --- a/net/net.c
>     >     +++ b/net/net.c
>     >     @@ -803,7 +803,9 @@ static int (* const net_client_init_fun
>     >     [NET_CLIENT_OPTIONS_KIND_MAX])(
>     >              [NET_CLIENT_OPTIONS_KIND_BRIDGE]    = net_init_bridge,
>     >      #endif
>     >              [NET_CLIENT_OPTIONS_KIND_HUBPORT]   = net_init_hubport,
>     >     +#ifdef CONFIG_VHOST_NET
>     >              [NET_CLIENT_OPTIONS_KIND_VHOST_USER] = net_init_vhost_user,
>     >     +#endif
>     >      };
>     >
>     >
>     >     @@ -837,7 +839,9 @@ static int net_client_init1(const void *object,
>     int
>     >     is_netdev, Error **errp)
>     >              case NET_CLIENT_OPTIONS_KIND_BRIDGE:
>     >      #endif
>     >              case NET_CLIENT_OPTIONS_KIND_HUBPORT:
>     >     +#ifdef CONFIG_VHOST_NET
>     >              case NET_CLIENT_OPTIONS_KIND_VHOST_USER:
>     >     +#endif
>     >                  break;
>     >
>     >              default:
>     >
>     >
>     >
>     > It turns out that configure puts CONFIG_VHOST_NET in the "wrong" place -
>     > config-target.h
>     >
>     > echo "CONFIG_VHOST_NET=y" >> $config_target_mak
>     >
>     > while for example:
>     >
>     > echo "CONFIG_VHOST_SCSI=y" >> $config_host_mak
>     >
>     > And net.c includes config-host.h, so we end up with vhost-user never
>     enabled in
>     > net.c.
> 
>     Not good.
> 
>     > Will it be a problem if CONFIG_VHOST_NET is added to config_host_mak
>     instead?
>     >
>     >
>     > regards,
>     > Nikolay Nikolaev
> 
>     Try it :)
>     It likely won't work for linux-user, right?
>    
>     --
>     MST
> 
> 
> You're right - its not working.
> 
> I ended up with this:
>        if test "$vhost_net" = "yes" ; then
>         echo "CONFIG_VHOST_NET=y" >> $config_target_mak
>         echo "CONFIG_VHOST_NET_USER=y" >> $config_host_mak
>        fi
> 
> and then in net.c depend on CONFIG_VHOST_NET_USER. Is this acceptable?

OK but
1. pls rename CONFIG_VHOST_NET_USED
2. you will make it appear many times in .mak, that's ugly,
   pls set a variable and output once.

> 
> I'm preparing a patchseries including the vhost-user qtest fixes, and can
> include this solution there if OK.
> 
> regards,
> Nikolay Nikolaev