| Message ID | 20221119171841.2014936-1-bjorn@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 837a3d66d698516ad2330e122eba9752ec3a48ed |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next] selftests: net: Add cross-compilation support for BPF programs | expand |
On Sat, 19 Nov 2022 at 18:19, Björn Töpel <bjorn@kernel.org> wrote: > > From: Björn Töpel <bjorn@rivosinc.com> > > The selftests/net does not have proper cross-compilation support, and > does not properly state libbpf as a dependency. Mimic/copy the BPF > build from selftests/bpf, which has the nice side-effect that libbpf > is built as well. > > Signed-off-by: Björn Töpel <bjorn@rivosinc.com> > --- > Now that BPF builds are starting to show up in more places > (selftests/net, and soon selftests/hid), maybe it would be cleaner to > move parts of the BPF builds to lib.mk? Yes, since its in tc-testing too. Maybe thats what we should do already now? Cheers, Anders > > Björn > --- > tools/testing/selftests/net/bpf/Makefile | 45 +++++++++++++++++++++--- > 1 file changed, 41 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/net/bpf/Makefile b/tools/testing/selftests/net/bpf/Makefile > index 8ccaf8732eb2..a26cb94354f6 100644 > --- a/tools/testing/selftests/net/bpf/Makefile > +++ b/tools/testing/selftests/net/bpf/Makefile > @@ -1,14 +1,51 @@ > # SPDX-License-Identifier: GPL-2.0 > > CLANG ?= clang > +SCRATCH_DIR := $(OUTPUT)/tools > +BUILD_DIR := $(SCRATCH_DIR)/build > +BPFDIR := $(abspath ../../../lib/bpf) > +APIDIR := $(abspath ../../../include/uapi) > + > CCINCLUDE += -I../../bpf > -CCINCLUDE += -I../../../../lib > CCINCLUDE += -I../../../../../usr/include/ > +CCINCLUDE += -I$(SCRATCH_DIR)/include > + > +BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a > + > +MAKE_DIRS := $(BUILD_DIR)/libbpf > +$(MAKE_DIRS): > + mkdir -p $@ > > TEST_CUSTOM_PROGS = $(OUTPUT)/bpf/nat6to4.o > all: $(TEST_CUSTOM_PROGS) > > -$(OUTPUT)/%.o: %.c > - $(CLANG) -O2 -target bpf -c $< $(CCINCLUDE) -o $@ > +# Get Clang's default includes on this system, as opposed to those seen by > +# '-target bpf'. This fixes "missing" files on some architectures/distros, > +# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. > +# > +# Use '-idirafter': Don't interfere with include mechanics except where the > +# build would have failed anyways. > +define get_sys_includes > +$(shell $(1) $(2) -v -E - </dev/null 2>&1 \ > + | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ > +$(shell $(1) $(2) -dM -E - </dev/null | grep '__riscv_xlen ' | awk '{printf("-D__riscv_xlen=%d -D__BITS_PER_LONG=%d", $$3, $$3)}') > +endef > + > +ifneq ($(CROSS_COMPILE),) > +CLANG_TARGET_ARCH = --target=$(notdir $(CROSS_COMPILE:%-=%)) > +endif > + > +CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH)) > + > +$(TEST_CUSTOM_PROGS): $(BPFOBJ) > + $(CLANG) -O2 -target bpf -c $(@:.o=.c) $(CCINCLUDE) $(CLANG_SYS_INCLUDES) -o $@ > + > +$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ > + $(APIDIR)/linux/bpf.h \ > + | $(BUILD_DIR)/libbpf > + $(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \ > + EXTRA_CFLAGS='-g -O0' \ > + DESTDIR=$(SCRATCH_DIR) prefix= all install_headers > + > +EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) > > -EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) > > base-commit: 8bd8dcc5e47f0f9dc40187c3b8b42d992181eee1 > -- > 2.37.2 >
Anders Roxell <anders.roxell@linaro.org> writes: > On Sat, 19 Nov 2022 at 18:19, Björn Töpel <bjorn@kernel.org> wrote: [...] >> Now that BPF builds are starting to show up in more places >> (selftests/net, and soon selftests/hid), maybe it would be cleaner to >> move parts of the BPF builds to lib.mk? > > Yes, since its in tc-testing too. > Maybe thats what we should do already now? Ok, so there's three BPF builds, in addition to selftests/bpf. Do you suggest moving (cross-compiled) libbpf builds (for bpf_helpers_defs.h generation) and some kind of clang BPF build-rule to lib.mk? Or would you like more things there, like resolve_btfids? I guess this patch could go in regardless, and fix the build *now*, and do a lib.mk thing as a follow-up? Björn
On Mon, 21 Nov 2022 at 17:48, Björn Töpel <bjorn@kernel.org> wrote: > > Anders Roxell <anders.roxell@linaro.org> writes: > > > On Sat, 19 Nov 2022 at 18:19, Björn Töpel <bjorn@kernel.org> wrote: > [...] > >> Now that BPF builds are starting to show up in more places > >> (selftests/net, and soon selftests/hid), maybe it would be cleaner to > >> move parts of the BPF builds to lib.mk? > > > > Yes, since its in tc-testing too. > > Maybe thats what we should do already now? > > Ok, so there's three BPF builds, in addition to selftests/bpf. Do you > suggest moving (cross-compiled) libbpf builds (for bpf_helpers_defs.h > generation) and some kind of clang BPF build-rule to lib.mk? Maybe start with moving the libbpf builds, for build_helpers_defs.h generation, and 'define get_sys_includes' into the lib.mk ? > Or would > you like more things there, like resolve_btfids? > > I guess this patch could go in regardless, and fix the build *now*, and > do a lib.mk thing as a follow-up? Make sense. Reviewed-by: Anders Roxell <anders.roxell@linaro.org> Cheers, Anders
On Sat, 2022-11-19 at 18:18 +0100, Björn Töpel wrote: > From: Björn Töpel <bjorn@rivosinc.com> > > The selftests/net does not have proper cross-compilation support, and > does not properly state libbpf as a dependency. Mimic/copy the BPF > build from selftests/bpf, which has the nice side-effect that libbpf > is built as well. > > Signed-off-by: Björn Töpel <bjorn@rivosinc.com> > --- > Now that BPF builds are starting to show up in more places > (selftests/net, and soon selftests/hid), maybe it would be cleaner to > move parts of the BPF builds to lib.mk? +1 on such follow-up ;) Thanks! Paolo
Hello: This patch was applied to netdev/net-next.git (master) by Paolo Abeni <pabeni@redhat.com>: On Sat, 19 Nov 2022 18:18:41 +0100 you wrote: > From: Björn Töpel <bjorn@rivosinc.com> > > The selftests/net does not have proper cross-compilation support, and > does not properly state libbpf as a dependency. Mimic/copy the BPF > build from selftests/bpf, which has the nice side-effect that libbpf > is built as well. > > [...] Here is the summary with links: - [net-next] selftests: net: Add cross-compilation support for BPF programs https://git.kernel.org/netdev/net-next/c/837a3d66d698 You are awesome, thank you!
diff --git a/tools/testing/selftests/net/bpf/Makefile b/tools/testing/selftests/net/bpf/Makefile index 8ccaf8732eb2..a26cb94354f6 100644 --- a/tools/testing/selftests/net/bpf/Makefile +++ b/tools/testing/selftests/net/bpf/Makefile @@ -1,14 +1,51 @@ # SPDX-License-Identifier: GPL-2.0 CLANG ?= clang +SCRATCH_DIR := $(OUTPUT)/tools +BUILD_DIR := $(SCRATCH_DIR)/build +BPFDIR := $(abspath ../../../lib/bpf) +APIDIR := $(abspath ../../../include/uapi) + CCINCLUDE += -I../../bpf -CCINCLUDE += -I../../../../lib CCINCLUDE += -I../../../../../usr/include/ +CCINCLUDE += -I$(SCRATCH_DIR)/include + +BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a + +MAKE_DIRS := $(BUILD_DIR)/libbpf +$(MAKE_DIRS): + mkdir -p $@ TEST_CUSTOM_PROGS = $(OUTPUT)/bpf/nat6to4.o all: $(TEST_CUSTOM_PROGS) -$(OUTPUT)/%.o: %.c - $(CLANG) -O2 -target bpf -c $< $(CCINCLUDE) -o $@ +# Get Clang's default includes on this system, as opposed to those seen by +# '-target bpf'. This fixes "missing" files on some architectures/distros, +# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. +# +# Use '-idirafter': Don't interfere with include mechanics except where the +# build would have failed anyways. +define get_sys_includes +$(shell $(1) $(2) -v -E - </dev/null 2>&1 \ + | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ +$(shell $(1) $(2) -dM -E - </dev/null | grep '__riscv_xlen ' | awk '{printf("-D__riscv_xlen=%d -D__BITS_PER_LONG=%d", $$3, $$3)}') +endef + +ifneq ($(CROSS_COMPILE),) +CLANG_TARGET_ARCH = --target=$(notdir $(CROSS_COMPILE:%-=%)) +endif + +CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH)) + +$(TEST_CUSTOM_PROGS): $(BPFOBJ) + $(CLANG) -O2 -target bpf -c $(@:.o=.c) $(CCINCLUDE) $(CLANG_SYS_INCLUDES) -o $@ + +$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ + $(APIDIR)/linux/bpf.h \ + | $(BUILD_DIR)/libbpf + $(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \ + EXTRA_CFLAGS='-g -O0' \ + DESTDIR=$(SCRATCH_DIR) prefix= all install_headers + +EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) -EXTRA_CLEAN := $(TEST_CUSTOM_PROGS)