Messages in this thread | | | Subject | Re: [PATCH bpf-next] samples: bpf: Fix cross-compiling error about bpftool | From | Pu Lehui <> | Date | Sat, 9 Jul 2022 15:31:33 +0800 |
| |
On 2022/7/9 6:42, Andrii Nakryiko wrote: > On Thu, Jul 7, 2022 at 6:37 AM Pu Lehui <pulehui@huawei.com> wrote: >> >> Currently, when cross compiling bpf samples, the host side >> cannot use arch-specific bpftool to generate vmlinux.h or >> skeleton. We need to compile the bpftool with the host >> compiler. >> >> Signed-off-by: Pu Lehui <pulehui@huawei.com> >> --- > > samples/bpf use bpftool for vmlinux.h, skeleton, and static linking > only. All that is supported by lightweight "bootstrap" bpftool > version, so we can build just that. It will be faster, and bootstrap > version should be always host-native even during cross compilation. > See [0] for what I did in libbpf-bootstrap. > > Also please cc Quention for bpftool-related changes. Thanks! > > [0] https://github.com/libbpf/libbpf-bootstrap/commit/fc28424eb3f0e39cfb5959296b070389b9a8bd8f >
so brilliant,we can take it to other places where rely on bpftool. thanks.
>> samples/bpf/Makefile | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile >> index 5002a5b9a7da..fe54a8c8f312 100644 >> --- a/samples/bpf/Makefile >> +++ b/samples/bpf/Makefile >> @@ -1,4 +1,5 @@ >> # SPDX-License-Identifier: GPL-2.0 >> +-include tools/scripts/Makefile.include >> >> BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src)) >> TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools >> @@ -283,11 +284,10 @@ $(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OU >> BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool >> BPFTOOL_OUTPUT := $(abspath $(BPF_SAMPLES_PATH))/bpftool >> BPFTOOL := $(BPFTOOL_OUTPUT)/bpftool >> -$(BPFTOOL): $(LIBBPF) $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT) >> +$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT) >> $(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../ \ >> - OUTPUT=$(BPFTOOL_OUTPUT)/ \ >> - LIBBPF_OUTPUT=$(LIBBPF_OUTPUT)/ \ >> - LIBBPF_DESTDIR=$(LIBBPF_DESTDIR)/ >> + ARCH= CROSS_COMPILE= CC=$(HOSTCC) LD=$(HOSTLD) \ >> + OUTPUT=$(BPFTOOL_OUTPUT)/ >> >> $(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT): >> $(call msg,MKDIR,$@) >> -- >> 2.25.1 >> > . >
| |