Messages in this thread |  | | Date | Thu, 31 Mar 2016 20:19:24 +0200 | | From | Daniel Borkmann <> | | Subject | Re: [PATCH 2/4] samples/bpf: Use llc in PATH, rather than a hardcoded value |
| |
On 03/31/2016 07:46 PM, Alexei Starovoitov wrote: > On 3/31/16 4:25 AM, Naveen N. Rao wrote: >> While at it, fix some typos in the comment. >> >> Cc: Alexei Starovoitov <ast@fb.com> >> Cc: David S. Miller <davem@davemloft.net> >> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> >> Cc: Michael Ellerman <mpe@ellerman.id.au> >> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> >> --- >> samples/bpf/Makefile | 11 ++++------- >> 1 file changed, 4 insertions(+), 7 deletions(-) >> >> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile >> index 502c9fc..88bc5a0 100644 >> --- a/samples/bpf/Makefile >> +++ b/samples/bpf/Makefile >> @@ -76,16 +76,13 @@ HOSTLOADLIBES_offwaketime += -lelf >> HOSTLOADLIBES_spintest += -lelf >> HOSTLOADLIBES_map_perf_test += -lelf -lrt >> >> -# point this to your LLVM backend with bpf support >> -LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc >> - >> -# asm/sysreg.h inline assmbly used by it is incompatible with llvm. >> -# But, ehere is not easy way to fix it, so just exclude it since it is >> +# 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. >> $(obj)/%.o: $(src)/%.c >> clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \ >> -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ >> - -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@ >> + -O2 -emit-llvm -c $< -o -| llc -march=bpf -filetype=obj -o $@ >> clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \ >> -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ >> - -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=asm -o $@.s >> + -O2 -emit-llvm -c $< -o -| llc -march=bpf -filetype=asm -o $@.s > > that was a workaround when clang/llvm didn't have bpf support. > Now clang 3.7 and 3.8 have bpf built-in, so make sense to remove > manual calls to llc completely. > Just use 'clang -target bpf -O2 -D... -c $< -o $@'
+1, the clang part in that Makefile should also more correctly be called with '-target bpf' as it turns out (despite llc with '-march=bpf' ...). Better to use clang directly as suggested by Alexei.
|  |