configure: Don't fail on missing bpftool

Instead of bailing out of configure if bpftool is not found, just disable compilation of the tools that require it (i.e., xdp-bench, xdp-monitor and xdp-trafficgen which use BPF skeletons). Signed-off-by: Toke Høiland-Jørgensen <[email protected]>
vproxy-tools · Oct 20, 2023 · 2b139e0 · 2b139e0
1 parent 1dc1e78
commit 2b139e0
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Showing 4 changed files with 28 additions and 8 deletions.
diff --git a/Makefile b/Makefile
@@ -14,8 +14,14 @@ MAKEFLAGS += --no-print-directory
 endif
 
 include version.mk
+include config.mk
+
+UTILS := xdp-filter xdp-loader xdp-dump
+
+ifneq ($(BPFTOOL),)
+UTILS += xdp-bench xdp-monitor xdp-trafficgen
+endif
 
-UTILS := xdp-filter xdp-loader xdp-dump xdp-bench xdp-monitor xdp-trafficgen
 SUBDIRS := lib $(UTILS)
 .PHONY: check_submodule help clobber distclean clean install test libxdp $(SUBDIRS)
 

diff --git a/configure b/configure
@@ -73,7 +73,7 @@ check_toolchain()
     CLANG=$(find_tool clang "$CLANG")
     LLC=$(find_tool llc "$LLC")
 
-    for TOOL in $PKG_CONFIG $CC $LD $OBJCOPY $CLANG $LLC $M4 $BPFTOOL $READELF; do
+    for TOOL in $PKG_CONFIG $CC $LD $OBJCOPY $CLANG $LLC $M4 $READELF; do
         if [ ! $(command -v ${TOOL} 2>/dev/null) ]; then
             echo "*** ERROR: Cannot find tool ${TOOL}" ;
             exit 1;
@@ -112,12 +112,12 @@ check_toolchain()
         exit 1
     fi
 
-    if $BPFTOOL gen help 2>&1 | grep 'gen skeleton.*name' > /dev/null; then
+    if command -v $BPFTOOL &>/dev/null && $BPFTOOL gen help 2>&1 | grep 'gen skeleton.*name' > /dev/null; then
         bpftool_version=$($BPFTOOL version | head -n 1)
 	echo "using $bpftool_version"
     else
-	echo "bpftool doesn't support skeleton generation"
-        exit 1
+	echo "bpftool not found or doesn't support skeleton generation; not building all tools"
+        BPFTOOL=
     fi
 
     if [ -z "$ARCH_INCLUDES" ] && [ -n "$ARCH_NAME" ]; then
@@ -137,8 +137,9 @@ check_toolchain()
     echo "M4:=${M4}" >>$CONFIG
     echo "EMACS:=${EMACS}" >>$CONFIG
     echo "ARCH_INCLUDES:=$ARCH_INCLUDES" >> $CONFIG
-    echo "BPFTOOL:=${BPFTOOL}" >> $CONFIG
     echo "READELF:=${READELF}" >> $CONFIG
+    echo "BPFTOOL:=${BPFTOOL}" >> $CONFIG
+    [ -n "$BPFTOOL" ] && echo "HAVE_FEATURES+=BPFTOOL" >>"$CONFIG"
 }
 
 check_zlib()

diff --git a/lib/testing/test-tool.c b/lib/testing/test-tool.c
@@ -205,10 +205,14 @@ int do_probe(const void *cfg, __unused const char *pin_root_path)
 
 	switch (opt->action) {
 	case PROBE_CPUMAP_PROGRAM:
+#ifdef HAVE_BPFTOOL
 		res = sample_probe_cpumap_compat();
+#endif
 		break;
 	case PROBE_XDP_LOAD_BYTES:
+#ifdef HAVE_BPFTOOL
 		res = sample_probe_xdp_load_bytes();
+#endif
 		break;
         default:
                 return EXIT_FAILURE;

diff --git a/lib/util/util.mk b/lib/util/util.mk
@@ -1,2 +1,11 @@
-UTIL_OBJS := params.o logging.o util.o stats.o xpcapng.o xdp_sample.o
-UTIL_BPF_OBJS := xdp_sample.bpf.o xdp_load_bytes.bpf.o
+LIB_DIR ?= ..
+include $(LIB_DIR)/defines.mk
+
+UTIL_OBJS := params.o logging.o util.o stats.o xpcapng.o
+UTIL_BPF_OBJS :=
+
+ifneq ($(BPFTOOL),)
+UTIL_OBJS += xdp_sample.o
+UTIL_BPF_OBJS += xdp_sample.bpf.o xdp_load_bytes.bpf.o
+endif
+