bpf: Add -target to clang switch while cross compiling.

Update to llvm excludes assembly instructions.
llvm git revision is below

commit 65fad7c26569 ("bpf: add inline-asm support")

This change will be part of llvm  release 6.0

__ASM_SYSREG_H define is not required for native compile.
-target switch includes appropriate target specific files
while cross compiling

Tested on x86 and arm64.

Signed-off-by: Abhijit Ayarekar <abhijit.ayarekar@caviumnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index ebc2ad69b62c0c773d741d928145e84244c187e7..81f9fcd736b7a3aaf5c698081dab986e5edac731 100644 (file)
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -180,6 +180,7 @@ CLANG ?= clang
 # Detect that we're cross compiling and use the cross compiler
 ifdef CROSS_COMPILE
 HOSTCC = $(CROSS_COMPILE)gcc
+CLANG_ARCH_ARGS = -target $(ARCH)
 endif
 
 # Trick to allow make to be run from this directory
@@ -229,9 +230,9 @@ $(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
 $(obj)/%.o: $(src)/%.c
        $(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
                -I$(srctree)/tools/testing/selftests/bpf/ \
-               -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
+               -D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \
                -D__TARGET_ARCH_$(ARCH) -Wno-compare-distinct-pointer-types \
                -Wno-gnu-variable-sized-type-not-at-end \
                -Wno-address-of-packed-member -Wno-tautological-compare \
-               -Wno-unknown-warning-option \
+               -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
                -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@