[RFC PATCH 3/3] net/af_xdp: use autoconf file instead of cflags

[Ciara Loftus <ciara.loftus@intel.com>]

Generate af_xdp_autoconf.h which contains the different features
detected by the meson build instead of using cflags.

Suggested-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
---
 drivers/net/af_xdp/compat.h    |  8 +++++---
 drivers/net/af_xdp/meson.build | 15 ++++++++-------
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/drivers/net/af_xdp/compat.h b/drivers/net/af_xdp/compat.h
index 28ea64aeaa..e1f8ead7c8 100644
--- a/drivers/net/af_xdp/compat.h
+++ b/drivers/net/af_xdp/compat.h
@@ -2,7 +2,9 @@
  * Copyright(c) 2020 Intel Corporation.
  */
 
-#ifdef RTE_NET_AF_XDP_LIBXDP
+#include "af_xdp_autoconf.h"
+
+#ifdef HAVE_LIBXDP
 #include <xdp/xsk.h>
 #else
 #include <bpf/xsk.h>
@@ -12,7 +14,7 @@
 #include <poll.h>
 
 #if KERNEL_VERSION(5, 10, 0) <= LINUX_VERSION_CODE && \
-	defined(RTE_NET_AF_XDP_SHARED_UMEM)
+	defined(HAVE_LIBBPF_SHARED_UMEM)
 #define ETH_AF_XDP_SHARED_UMEM 1
 #endif
 
@@ -60,7 +62,7 @@ tx_syscall_needed(struct xsk_ring_prod *q __rte_unused)
 }
 #endif
 
-#ifdef RTE_NET_AF_XDP_LIBBPF_OBJ_OPEN
+#ifdef HAVE_LIBBPF_OBJ_OPEN
 static int load_program(const char *prog_path, struct bpf_object **obj)
 {
 	struct bpf_program *prog;
diff --git a/drivers/net/af_xdp/meson.build b/drivers/net/af_xdp/meson.build
index d91545f9c3..d1f6febbca 100644
--- a/drivers/net/af_xdp/meson.build
+++ b/drivers/net/af_xdp/meson.build
@@ -23,15 +23,17 @@ if bpf_dep.found() and cc.has_header('bpf/bpf.h') and cc.has_header_symbol('bpf/
     libbpf070 = true
 endif
 
+config = configuration_data()
+
 if cc.has_header('linux/if_xdp.h')
     if xdp_dep.found() and cc.has_header('xdp/xsk.h')
         if bpf_dep.found() and cc.has_header('bpf/bpf.h')
-            cflags += ['-DRTE_NET_AF_XDP_LIBXDP']
-            cflags += ['-DRTE_NET_AF_XDP_SHARED_UMEM']
+            config.set('HAVE_LIBXDP', 1)
+            config.set('HAVE_LIBBPF_SHARED_UMEM', 1)
             ext_deps += xdp_dep
             ext_deps += bpf_dep
             if libbpf070
-                cflags += ['-DRTE_NET_AF_XDP_LIBBPF_OBJ_OPEN']
+                config.set('HAVE_LIBBPF_OBJ_OPEN', 1)
             endif
         else
             build = false
@@ -42,10 +44,7 @@ if cc.has_header('linux/if_xdp.h')
         # which is only available in versions < v0.7.0.
         if not libbpf070
             ext_deps += bpf_dep
-            bpf_shumem_ver_dep = cc.has_header_symbol('bpf/bpf.h', 'bpf_prog_bind_map')
-            if bpf_shumem_ver_dep
-                cflags += ['-DRTE_NET_AF_XDP_SHARED_UMEM']
-            endif
+            config.set('HAVE_LIBBPF_SHARED_UMEM', cc.has_header_symbol('bpf/bpf.h', 'bpf_prog_bind_map'))
         else
             build = false
             reason = 'missing dependency, "libxdp" or "libbpf <= v0.6.0"'
@@ -58,3 +57,5 @@ else
     build = false
     reason = 'missing header, "linux/if_xdp.h"'
 endif
+
+configure_file(output : 'af_xdp_autoconf.h', configuration : config)
-- 
2.25.1