libbpf-tools: determine target host architecture
BPF code is compiled with -target bpf, but for PT_REGS_PARM macro (and by
induction for BPF_KPROBE/BPF_KRETPROBE macros as well), it's important to know
what's the target host original architecture was, to use correct definition of
struct pt_regs. Determine that based on output of `uname -m` (taking into
account that both x86_64 and x86 are defined as x86 internally for kernel).
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
diff --git a/libbpf-tools/Makefile b/libbpf-tools/Makefile
index 399a086..1d2b153 100644
--- a/libbpf-tools/Makefile
+++ b/libbpf-tools/Makefile
@@ -7,6 +7,7 @@
LIBBPF_OBJ := $(abspath $(OUTPUT)/libbpf.a)
INCLUDES := -I$(OUTPUT)
CFLAGS := -g -O2 -Wall
+ARCH := $(shell uname -m | sed 's/x86_64/x86/')
APPS = drsnoop opensnoop runqslower
@@ -47,8 +48,8 @@
$(OUTPUT)/%.bpf.o: %.bpf.c $(LIBBPF_OBJ) $(wildcard %.h) vmlinux.h | $(OUTPUT)
$(call msg,BPF,$@)
- $(Q)$(CLANG) -g -O2 -target bpf $(INCLUDES) \
- -c $(filter %.c,$^) -o $@ && \
+ $(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(ARCH) \
+ $(INCLUDES) -c $(filter %.c,$^) -o $@ && \
$(LLVM_STRIP) -g $@
# Build libbpf.a
