From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Date: Sat, 21 Aug 2021 05:50:00 +0530
Subject: samples: bpf: Add vmlinux.h generation support
Patch-mainline: v5.15-rc1
Git-commit: 384b6b3bbf0d3b60ca118459a91b7b8ce1dcd6bd
References: jsc#PED-1377
Also, take this opportunity to depend on in-tree bpftool, so that we can
use static linking support in subsequent commits for XDP samples BPF
helper object.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-13-memxor@gmail.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
samples/bpf/Makefile | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -276,6 +276,11 @@ $(LIBBPF): FORCE
$(MAKE) -C $(dir $@) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(BPF_SAMPLES_PATH)/../../ O=
+BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
+BPFTOOL := $(BPFTOOLDIR)/bpftool
+$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)
+ $(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../
+
$(obj)/syscall_nrs.h: $(obj)/syscall_nrs.s FORCE
$(call filechk,offsets,__SYSCALL_NRS_H__)
@@ -313,6 +318,26 @@ $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(sr
-include $(BPF_SAMPLES_PATH)/Makefile.target
+VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
+ $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
+ ../../../../vmlinux \
+ /sys/kernel/btf/vmlinux \
+ /boot/vmlinux-$(shell uname -r)
+VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
+
+ifeq ($(VMLINUX_BTF),)
+$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)")
+endif
+
+$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
+ifeq ($(VMLINUX_H),)
+ $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@
+else
+ $(Q)cp "$(VMLINUX_H)" $@
+endif
+
+clean-files += vmlinux.h
+
# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
# But, there is no easy way to fix it, so just exclude it since it is
# useless for BPF samples.