acinclude.m4: Build with AF_XDP support by default if possible.

With this change we will try to detect all the netdev-afxdp
dependencies and enable AF_XDP support by default if they are
present at the build time.

Configuration script behaves in a following way:

 - ./configure --enable-afxdp

   Will check for AF_XDP dependencies and fail if they are
   not available.

 - ./configure --disable-afxdp

   Disables checking for AF_XDP.  Build will not support
   AF_XDP even if all dependencies are installed.

 - Just ./configure or ./configure --enable-afxdp=auto

   Will check for AF_XDP dependencies.  Will print a warning
   if they are not available, but will continue without AF_XDP
   support.  If dependencies are available in a system, this
   option is equal to --enable-afxdp.

'--disable-afxdp' added to the debian and fedora package builds
to keep predictable behavior.

Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index ce5d11d73..2f6ededfe 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,9 @@ Post-v3.0.0
      of handler and revalidator threads if necessary.
    - AF_XDP:
      * Added support for building with libxdp and libbpf >= 0.7.
+     * Support for AF_XDP is now enabled by default if all dependencies are
+       available at the build time.  Use --disable-afxdp to disable.
+       Use --enable-afxdp to fail the build if dependencies are not present.
    - ovs-appctl:
      * "ovs-appctl ofproto/trace" command can now display port names with the
        "--names" option.