tools/bpftool: use version from the kernel source tree

Bpftool determines it's own version based on the kernel
version, which is picked from the linux/version.h header.

It's strange to use the version of the installed kernel
headers, and makes much more sense to use the version
of the actual source tree, where bpftool sources are.

Fix this by building kernelversion target and use
the resulting string as bpftool version.

Example:
before:

$ bpftool version
bpftool v4.14.6

after:
$ bpftool version
bpftool v4.15.0-rc3

$bpftool version --json
{"version":"4.15.0-rc3"}

Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index 3f17ad317512a8e7eb0e2b590c0742d2597c4592..f8f31a8d92698ad4e2118d960a2196bf8ae4179e 100644 (file)
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -23,6 +23,8 @@ endif
 
 LIBBPF = $(BPF_PATH)libbpf.a
 
+BPFTOOL_VERSION=$(shell make --no-print-directory -sC ../../.. kernelversion)
+
 $(LIBBPF): FORCE
        $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(OUTPUT) $(OUTPUT)libbpf.a FEATURES_DUMP=$(FEATURE_DUMP_EXPORT)
 
@@ -38,6 +40,7 @@ CC = gcc
 CFLAGS += -O2
 CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wshadow
 CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/tools/include/uapi -I$(srctree)/tools/include -I$(srctree)/tools/lib/bpf -I$(srctree)/kernel/bpf/
+CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
 LIBS = -lelf -lbfd -lopcodes $(LIBBPF)
 
 INSTALL ?= install

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index ecd53ccf1239c1a1a6c368fb673d552ec162a310..3a0396d87c424954ffe3e6c1111dca2a23bd3776 100644 (file)
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -38,7 +38,6 @@
 #include <errno.h>
 #include <getopt.h>
 #include <linux/bpf.h>
-#include <linux/version.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -95,21 +94,13 @@ static int do_help(int argc, char **argv)
 
 static int do_version(int argc, char **argv)
 {
-       unsigned int version[3];
-
-       version[0] = LINUX_VERSION_CODE >> 16;
-       version[1] = LINUX_VERSION_CODE >> 8 & 0xf;
-       version[2] = LINUX_VERSION_CODE & 0xf;
-
        if (json_output) {
                jsonw_start_object(json_wtr);
                jsonw_name(json_wtr, "version");
-               jsonw_printf(json_wtr, "\"%u.%u.%u\"",
-                            version[0], version[1], version[2]);
+               jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
                jsonw_end_object(json_wtr);
        } else {
-               printf("%s v%u.%u.%u\n", bin_name,
-                      version[0], version[1], version[2]);
+               printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
        }
        return 0;
 }