Re: [Qemu-devel] [PATCH v2 2/2] build-sys: do not compile net/vhost-user.c if vhost-user is disabled

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

On Fri, Jul 28, 2017 at 04:13:09PM +0200, Marc-André Lureau wrote:
> This adds two extra #ifdef that have fairly limited conflict potential.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

OK but why can't we keep all ifdefs in net/ where all the
rest of the features are ifdef'ed?

My concern is no one is going to test this weird configuration
so we might accidentally re-enable it without noticing.
net/net.c is where all command line play happens so
people know a bunch of configs need to be tested when
changing it.


> ---
>  hw/net/vhost_net.c | 4 ++++
>  net/Makefile.objs  | 2 +-
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> index e037db63a3..96c4da49e4 100644
> --- a/hw/net/vhost_net.c
> +++ b/hw/net/vhost_net.c
> @@ -193,6 +193,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
>          }
>      }
>  
> +#ifdef CONFIG_VHOST_USER
>      /* Set sane init value. Override when guest acks. */
>      if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
>          features = vhost_user_get_acked_features(net->nc);
> @@ -203,6 +204,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
>              goto fail;
>          }
>      }
> +#endif
>  
>      vhost_net_ack_features(net, features);
>  
> @@ -414,10 +416,12 @@ VHostNetState *get_vhost_net(NetClientState *nc)
>      case NET_CLIENT_DRIVER_TAP:
>          vhost_net = tap_get_vhost_net(nc);
>          break;
> +#ifdef CONFIG_VHOST_USER
>      case NET_CLIENT_DRIVER_VHOST_USER:
>          vhost_net = vhost_user_get_vhost_net(nc);
>          assert(vhost_net);
>          break;
> +#endif
>      default:
>          break;
>      }
> diff --git a/net/Makefile.objs b/net/Makefile.objs
> index 67ba5e26fb..7cac7ed1e4 100644
> --- a/net/Makefile.objs
> +++ b/net/Makefile.objs
> @@ -3,7 +3,7 @@ common-obj-y += socket.o
>  common-obj-y += dump.o
>  common-obj-y += eth.o
>  common-obj-$(CONFIG_L2TPV3) += l2tpv3.o
> -common-obj-$(CONFIG_POSIX) += vhost-user.o
> +common-obj-$(CONFIG_VHOST_USER) += vhost-user.o
>  common-obj-$(CONFIG_SLIRP) += slirp.o
>  common-obj-$(CONFIG_VDE) += vde.o
>  common-obj-$(CONFIG_NETMAP) += netmap.o
> -- 
> 2.14.0.rc0.1.g40ca67566