2019-10-09 20:42:23

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 00/15] samples: bpf: improve/fix cross-compilation

This series contains mainly fixes/improvements for cross-compilation
but not only, tested for arm, arm64, and intended for any arch.
Also verified on native build (not cross compilation) for x86_64
and arm, arm64.

Initial RFC link:
https://lkml.org/lkml/2019/8/29/1665

Prev. version:
https://lkml.org/lkml/2019/9/16/231

Besides the patches given here, the RFC also contains couple patches
related to llvm clang
arm: include: asm: swab: mask rev16 instruction for clang
arm: include: asm: unified: mask .syntax unified for clang
They are necessarily to verify arm 32 build.

Also, couple more fixes were added but are not merged in bpf-next yet,
they can be needed for verification/configuration steps, if not in
your tree the fixes can be taken here:
https://www.spinics.net/lists/netdev/msg601716.html
https://www.spinics.net/lists/netdev/msg601714.html
https://www.spinics.net/lists/linux-kbuild/msg23468.html

Now, to build samples, SAMPLE_BPF should be enabled in config.

The change touches not only cross-compilation and can have impact on
other archs and build environments, so might be good idea to verify
it in order to add appropriate changes, some warn options could be
tuned also.

All is tested on x86-64 with clang installed (has to be built containing
targets for arm, arm64..., see llc --version, usually it's present already)

Instructions to test native on x86_64
=================================================
Native build on x86_64 is done in usual way and shouldn't have difference
except HOSTCC is now printed as CC wile building the samples.

Instructions to test cross compilation on arm64
=================================================
#Toolchain used for test:
gcc version 8.3.0
(GNU Toolchain for the A-profile Architecture 8.3-2019.03 (arm-rel-8.36))

# Get some arm64 FS, containing at least libelf
I've used sdk for TI am65x got here:
http://downloads.ti.com/processor-sdk-linux/esd/AM65X/latest/exports/\
ti-processor-sdk-linux-am65xx-evm-06.00.00.07-Linux-x86-Install.bin

# Install this binary to some dir, say "sdk".
# Configure kernel (use defconfig as no matter), but clean everything
# before.
make ARCH=arm64 -C tools/ clean
make ARCH=arm64 -C samples/bpf clean
make ARCH=arm64 clean
make ARCH=arm64 defconfig

# Enable SAMPLE_BPF and it's dependencies in config

# The kernel version used in sdk doesn't correspond to checked one,
# but for this verification only headers need to be syched,
# so install them (can be enabled in config):
make ARCH=arm64 headers_install

# or on SDK if need keep them in sync (not necessarily to verify):

make ARCH=arm64 INSTALL_HDR_PATH=/../sdk/\
ti-processor-sdk-linux-am65xx-evm-06.00.00.07/linux-devkit/sysroots/\
aarch64-linux/usr headers_install

# Build samples
make samples/bpf/ ARCH=arm64 CROSS_COMPILE="aarch64-linux-gnu-"\
SYSROOT="/../sdk/ti-processor-sdk-linux-am65xx-evm-06.00.00.07/\
linux-devkit/sysroots/aarch64-linux"

Instructions to test cross compilation on arm
=================================================
#Toolchains used for test:
arm-linux-gnueabihf-gcc (Linaro GCC 7.2-2017.11) 7.2.1 20171011
or
arm-linux-gnueabihf-gcc
(GNU Toolchain for the A-profile Architecture 8.3-2019.03 \
(arm-rel-8.36)) 8.3.0

# Get some FS, I've used sdk for TI am52xx got here:
http://downloads.ti.com/processor-sdk-linux/esd/AM57X/05_03_00_07/exports/\
ti-processor-sdk-linux-am57xx-evm-05.03.00.07-Linux-x86-Install.bin

# Install this binary to some dir, say "sdk".
# Configure kernel, but clean everything before.
make ARCH=arm -C tools/ clean
make ARCH=arm -C samples/bpf clean
make ARCH=arm clean
make ARCH=arm omap2plus_defconfig

# The kernel version used in sdk doesn't correspond to checked one, but
# headers only should be synched,
# so install them (can be enabled in config):

make ARCH=arm headers_install

# or on SDK if need keep them in sync (not necessarily):

make ARCH=arm INSTALL_HDR_PATH=/../sdk/\
ti-processor-sdk-linux-am57xx-evm-05.03.00.07/linux-devkit/sysroots/\
armv7ahf-neon-linux-gnueabi/usr headers_install

# Build samples
make samples/bpf/ ARCH=arm CROSS_COMPILE="arm-linux-gnueabihf-"\
SYSROOT="/../sdk/ti-processor-sdk-linux-am57xx-evm-05.03\
.00.07/linux-devkit/sysroots/armv7ahf-neon-linux-gnueabi"


Based on bpf-next/master

v4..v3:
- renamed CLANG_EXTRA_CFLAGS on BPF_EXTRA_CFLAGS
- used filter for ARCH_ARM_SELECTOR
- omit "-fomit-frame-pointer" and use same flags for native and "cross"
- used sample/bpf prefixes
- use C instead of C++ compiler for test_libbpf target

v3..v2:
- renamed makefile.progs to makeifle.target, as more appropriate
- left only __LINUX_ARM_ARCH__ for D options for arm
- for host build - left options from KBUILD_HOST for compatibility reasons
- split patch adding c/cxx/ld flags to libbpf by modules
- moved readme change to separate patch
- added patch setting options for cross-compile
- fixed issue with option error for syscall_nrs.S,
avoiding overlap for ccflags-y.

v2..v1:
- restructured patches order
- split "samples: bpf: Makefile: base progs build on Makefile.progs"
to make change more readable. It added couple nice extra patches.
- removed redundant patch:
"samples: bpf: Makefile: remove target for native build"
- added fix:
"samples: bpf: makefile: fix cookie_uid_helper_example obj build"
- limited -D option filter only for arm
- improved comments
- added couple instructions to verify cross compilation for arm and
arm64 arches based on TI am57xx and am65xx sdks.
- corrected include a little order

Ivan Khoronzhuk (15):
samples/bpf: fix HDR_PROBE "echo"
samples/bpf: fix cookie_uid_helper_example obj build
samples/bpf: use --target from cross-compile
samples/bpf: use own EXTRA_CFLAGS for clang commands
samples/bpf: use __LINUX_ARM_ARCH__ selector for arm
samples/bpf: drop unnecessarily inclusion for bpf_load
samples/bpf add makefile.target for separate CC target build
samples/bpf: base target programs rules on Makefile.target
samples/bpf: use own flags but not HOSTCFLAGS
samples/bpf: use target CC environment for HDR_PROBE
libbpf: don't use cxx to test_libpf target
libbpf: add C/LDFLAGS to libbpf.so and test_libpf targets
samples/bpf: provide C/LDFLAGS to libbpf
samples/bpf: add sysroot support
samples/bpf: add preparation steps and sysroot info to readme

samples/bpf/Makefile | 164 ++++++++++--------
samples/bpf/Makefile.target | 75 ++++++++
samples/bpf/README.rst | 41 ++++-
tools/lib/bpf/Makefile | 23 +--
.../bpf/{test_libbpf.cpp => test_libbpf.c} | 14 +-
5 files changed, 218 insertions(+), 99 deletions(-)
create mode 100644 samples/bpf/Makefile.target
rename tools/lib/bpf/{test_libbpf.cpp => test_libbpf.c} (61%)

--
2.17.1


2019-10-09 20:42:27

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 03/15] samples/bpf: use --target from cross-compile

For cross compiling the target triple can be inherited from
cross-compile prefix as it's done in CLANG_FLAGS from kernel makefile.
So copy-paste this decision from kernel Makefile.

Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 045fa43842e6..9c8c9872004d 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -195,7 +195,7 @@ BTF_PAHOLE ?= pahole
# Detect that we're cross compiling and use the cross compiler
ifdef CROSS_COMPILE
HOSTCC = $(CROSS_COMPILE)gcc
-CLANG_ARCH_ARGS = -target $(ARCH)
+CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
endif

# Don't evaluate probes and warnings if we need to run make recursively
--
2.17.1

2019-10-09 20:42:46

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 13/15] samples/bpf: provide C/LDFLAGS to libbpf

In order to build lib using C/LD flags of target arch, provide them
to libbpf make.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index a6c33496e8ca..6b161326ac67 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -248,7 +248,8 @@ clean:

$(LIBBPF): FORCE
# Fix up variables inherited from Kbuild that tools/ build system won't like
- $(MAKE) -C $(dir $@) RM='rm -rf' LDFLAGS= srctree=$(BPF_SAMPLES_PATH)/../../ O=
+ $(MAKE) -C $(dir $@) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
+ LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(BPF_SAMPLES_PATH)/../../ O=

$(obj)/syscall_nrs.h: $(obj)/syscall_nrs.s FORCE
$(call filechk,offsets,__SYSCALL_NRS_H__)
--
2.17.1

2019-10-09 20:42:54

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 14/15] samples/bpf: add sysroot support

Basically it only enables that was added by previous couple fixes.
Sysroot contains correct libs installed and its headers. Useful when
working with NFC or virtual machine.

Usage example:

clean (on demand)
make ARCH=arm -C samples/bpf clean
make ARCH=arm -C tools clean
make ARCH=arm clean

configure and install headers:

make ARCH=arm defconfig
make ARCH=arm headers_install

build samples/bpf:
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- samples/bpf/ \
SYSROOT="path/to/sysroot"

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 6b161326ac67..4df11ddb9c75 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -187,6 +187,11 @@ TPROGS_CFLAGS += -I$(srctree)/tools/lib/
TPROGS_CFLAGS += -I$(srctree)/tools/include
TPROGS_CFLAGS += -I$(srctree)/tools/perf

+ifdef SYSROOT
+TPROGS_CFLAGS += --sysroot=$(SYSROOT)
+TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
+endif
+
TPROGCFLAGS_bpf_load.o += -Wno-unused-variable

TPROGS_LDLIBS += $(LIBBPF) -lelf
--
2.17.1

2019-10-09 20:42:59

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 15/15] samples/bpf: add preparation steps and sysroot info to readme

Add couple preparation steps: clean and configuration. Also add newly
added sysroot support info to cross-compile section.
---
samples/bpf/README.rst | 41 ++++++++++++++++++++++++++++++++++++-----
1 file changed, 36 insertions(+), 5 deletions(-)

diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst
index 5f27e4faca50..cc1f00a1ee06 100644
--- a/samples/bpf/README.rst
+++ b/samples/bpf/README.rst
@@ -14,6 +14,20 @@ Compiling requires having installed:
Note that LLVM's tool 'llc' must support target 'bpf', list version
and supported targets with command: ``llc --version``

+Clean and configuration
+-----------------------
+
+It can be needed to clean tools, samples or kernel before trying new arch or
+after some changes (on demand)::
+
+ make -C tools clean
+ make -C samples/bpf clean
+ make clean
+
+Configure kernel, defconfig for instance::
+
+ make defconfig
+
Kernel headers
--------------

@@ -68,9 +82,26 @@ It is also possible to point make to the newly compiled 'llc' or
Cross compiling samples
-----------------------
In order to cross-compile, say for arm64 targets, export CROSS_COMPILE and ARCH
-environment variables before calling make. This will direct make to build
-samples for the cross target.
+environment variables before calling make. But do this before clean,
+cofiguration and header install steps described above. This will direct make to
+build samples for the cross target::
+
+ export ARCH=arm64
+ export CROSS_COMPILE="aarch64-linux-gnu-"
+
+Headers can be also installed on RFS of target board if need to keep them in
+sync (not necessarily and it creates a local "usr/include" directory also)::
+
+ make INSTALL_HDR_PATH=~/some_sysroot/usr headers_install
+
+Pointing LLC and CLANG is not necessarily if it's installed on HOST and have
+in its targets appropriate arm64 arch (usually it has several arches).
+Build samples::
+
+ make samples/bpf/
+
+Or build samples with SYSROOT if some header or library is absent in toolchain,
+say libelf, providing address to file system containing headers and libs,
+can be RFS of target board::

-export ARCH=arm64
-export CROSS_COMPILE="aarch64-linux-gnu-"
-make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
+ make samples/bpf/ SYSROOT=~/some_sysroot
--
2.17.1

2019-10-09 20:43:15

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 12/15] libbpf: add C/LDFLAGS to libbpf.so and test_libpf targets

In case of C/LDFLAGS there is no way to pass them correctly to build
command, for instance when --sysroot is used or external libraries
are used, like -lelf, wich can be absent in toolchain. This can be
used for samples/bpf cross-compiling allowing to get elf lib from
sysroot.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
tools/lib/bpf/Makefile | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 46280b5ad48d..75b538577c17 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -174,8 +174,9 @@ bpf_helper_defs.h: $(srctree)/include/uapi/linux/bpf.h
$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)

$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN)
- $(QUIET_LINK)$(CC) --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
- -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@
+ $(QUIET_LINK)$(CC) $(LDFLAGS) \
+ --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
+ -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@
@ln -sf $(@F) $(OUTPUT)libbpf.so
@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)

@@ -183,7 +184,7 @@ $(OUTPUT)libbpf.a: $(BPF_IN)
$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^

$(OUTPUT)test_libbpf: test_libbpf.c $(OUTPUT)libbpf.a
- $(QUIET_LINK)$(CC) $(INCLUDES) $^ -lelf -o $@
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(INCLUDES) $^ -lelf -o $@

$(OUTPUT)libbpf.pc:
$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
--
2.17.1

2019-10-09 20:43:23

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 11/15] libbpf: don't use cxx to test_libpf target

No need to use C++ for test_libbpf target when libbpf is on C and it
can be tested with C, after this change the CXXFLAGS in makefiles can
be avoided, at least in bpf samples, when sysroot is used, passing
same C/LDFLAGS as for lib.

Add "return 0" in test_libbpf to void warn, but also remove spaces at
start of the lines to keep same style and avoid warns while apply.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
tools/lib/bpf/Makefile | 18 +++++-------------
.../lib/bpf/{test_libbpf.cpp => test_libbpf.c} | 14 ++++++++------
2 files changed, 13 insertions(+), 19 deletions(-)
rename tools/lib/bpf/{test_libbpf.cpp => test_libbpf.c} (61%)

diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 1270955e4845..46280b5ad48d 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -52,7 +52,7 @@ ifndef VERBOSE
endif

FEATURE_USER = .libbpf
-FEATURE_TESTS = libelf libelf-mmap bpf reallocarray cxx
+FEATURE_TESTS = libelf libelf-mmap bpf reallocarray
FEATURE_DISPLAY = libelf bpf

INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
@@ -142,15 +142,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN) | \
VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so | \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)

-CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)
-
-CXX_TEST_TARGET = $(OUTPUT)test_libbpf
-
-ifeq ($(feature-cxx), 1)
- CMD_TARGETS += $(CXX_TEST_TARGET)
-endif
-
-TARGETS = $(CMD_TARGETS)
+CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) $(OUTPUT)test_libbpf

all: fixdep
$(Q)$(MAKE) all_cmd
@@ -190,8 +182,8 @@ $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN)
$(OUTPUT)libbpf.a: $(BPF_IN)
$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^

-$(OUTPUT)test_libbpf: test_libbpf.cpp $(OUTPUT)libbpf.a
- $(QUIET_LINK)$(CXX) $(INCLUDES) $^ -lelf -o $@
+$(OUTPUT)test_libbpf: test_libbpf.c $(OUTPUT)libbpf.a
+ $(QUIET_LINK)$(CC) $(INCLUDES) $^ -lelf -o $@

$(OUTPUT)libbpf.pc:
$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
@@ -266,7 +258,7 @@ config-clean:
$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null

clean:
- $(call QUIET_CLEAN, libbpf) $(RM) $(TARGETS) $(CXX_TEST_TARGET) \
+ $(call QUIET_CLEAN, libbpf) $(RM) $(CMD_TARGETS) \
*.o *~ *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) .*.d .*.cmd \
*.pc LIBBPF-CFLAGS bpf_helper_defs.h
$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
diff --git a/tools/lib/bpf/test_libbpf.cpp b/tools/lib/bpf/test_libbpf.c
similarity index 61%
rename from tools/lib/bpf/test_libbpf.cpp
rename to tools/lib/bpf/test_libbpf.c
index fc134873bb6d..f0eb2727b766 100644
--- a/tools/lib/bpf/test_libbpf.cpp
+++ b/tools/lib/bpf/test_libbpf.c
@@ -7,12 +7,14 @@

int main(int argc, char *argv[])
{
- /* libbpf.h */
- libbpf_set_print(NULL);
+ /* libbpf.h */
+ libbpf_set_print(NULL);

- /* bpf.h */
- bpf_prog_get_fd_by_id(0);
+ /* bpf.h */
+ bpf_prog_get_fd_by_id(0);

- /* btf.h */
- btf__new(NULL, 0);
+ /* btf.h */
+ btf__new(NULL, 0);
+
+ return 0;
}
--
2.17.1

2019-10-09 20:43:30

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 09/15] samples/bpf: use own flags but not HOSTCFLAGS

While compiling natively, the host's cflags and ldflags are equal to
ones used from HOSTCFLAGS and HOSTLDFLAGS. When cross compiling it
should have own, used for target arch. While verification, for arm,
arm64 and x86_64 the following flags were used always:

-Wall -O2
-fomit-frame-pointer
-Wmissing-prototypes
-Wstrict-prototypes

So, add them as they were verified and used before adding
Makefile.target and lets omit "-fomit-frame-pointer" as were
proposed while review, as no sense in such optimization for samples.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 91bfb421c278..57a15ff938a6 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -176,8 +176,10 @@ BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
endif

-TPROGS_LDLIBS := $(KBUILD_HOSTLDLIBS)
-TPROGS_CFLAGS += $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS)
+TPROGS_CFLAGS += -Wall -O2
+TPROGS_CFLAGS += -Wmissing-prototypes
+TPROGS_CFLAGS += -Wstrict-prototypes
+
TPROGS_CFLAGS += -I$(objtree)/usr/include
TPROGS_CFLAGS += -I$(srctree)/tools/lib/bpf/
TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
--
2.17.1

2019-10-09 20:43:55

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 06/15] samples/bpf: drop unnecessarily inclusion for bpf_load

Drop inclusion for bpf_load -I$(objtree)/usr/include as it is
included for all objects anyway, with above line:
KBUILD_HOSTCFLAGS += -I$(objtree)/usr/include

Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 9b33e7395eac..bb2d976e824e 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -176,7 +176,7 @@ KBUILD_HOSTCFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib/ -I$(srctree)/tools/include
KBUILD_HOSTCFLAGS += -I$(srctree)/tools/perf

-HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable
+HOSTCFLAGS_bpf_load.o += -Wno-unused-variable

KBUILD_HOSTLDLIBS += $(LIBBPF) -lelf
HOSTLDLIBS_tracex4 += -lrt
--
2.17.1

2019-10-09 20:44:30

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 04/15] samples/bpf: use own EXTRA_CFLAGS for clang commands

It can overlap with CFLAGS used for libraries built with gcc if
not now then in next patches. Correct it here for simplicity.

Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 9c8c9872004d..cf882e43648a 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -218,10 +218,10 @@ BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
/bin/rm -f ./llvm_btf_verify.o)

ifneq ($(BTF_LLVM_PROBE),)
- EXTRA_CFLAGS += -g
+ BPF_EXTRA_CFLAGS += -g
else
ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
- EXTRA_CFLAGS += -g
+ BPF_EXTRA_CFLAGS += -g
LLC_FLAGS += -mattr=dwarfris
DWARF2BTF = y
endif
@@ -280,8 +280,9 @@ $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
# useless for BPF samples.
$(obj)/%.o: $(src)/%.c
@echo " CLANG-bpf " $@
- $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
- -I$(srctree)/tools/testing/selftests/bpf/ -I$(srctree)/tools/lib/bpf/ \
+ $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \
+ -I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
+ -I$(srctree)/tools/lib/bpf/ \
-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
-D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
-Wno-gnu-variable-sized-type-not-at-end \
--
2.17.1

2019-10-09 20:44:32

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 07/15] samples/bpf: add makefile.target for separate CC target build

The Makefile.target is added only and will be used in
sample/bpf/Makefile later in order to switch cross-compiling to CC
from HOSTCC environment.

The HOSTCC is supposed to build binaries and tools running on the host
afterwards, in order to simplify build or so, like "fixdep" or else.
In case of cross compiling "fixdep" is executed on host when the rest
samples should run on target arch. In order to build binaries for
target arch with CC and tools running on host with HOSTCC, lets add
Makefile.target for simplicity, having definition and routines similar
to ones, used in script/Makefile.host. This allows later add
cross-compilation to samples/bpf with minimum changes.

The tprog stands for target programs built with CC.

Makefile.target contains only stuff needed for samples/bpf, potentially
can be reused later and now needed only for unblocking tricky
samples/bpf cross compilation.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile.target | 75 +++++++++++++++++++++++++++++++++++++
1 file changed, 75 insertions(+)
create mode 100644 samples/bpf/Makefile.target

diff --git a/samples/bpf/Makefile.target b/samples/bpf/Makefile.target
new file mode 100644
index 000000000000..7621f55e2947
--- /dev/null
+++ b/samples/bpf/Makefile.target
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+# ==========================================================================
+# Building binaries on the host system
+# Binaries are not used during the compilation of the kernel, and intended
+# to be build for target board, target board can be host of course. Added to
+# build binaries to run not on host system.
+#
+# Sample syntax
+# tprogs-y := xsk_example
+# Will compile xsk_example.c and create an executable named xsk_example
+#
+# tprogs-y := xdpsock
+# xdpsock-objs := xdpsock_1.o xdpsock_2.o
+# Will compile xdpsock_1.c and xdpsock_2.c, and then link the executable
+# xdpsock, based on xdpsock_1.o and xdpsock_2.o
+#
+# Derived from scripts/Makefile.host
+#
+__tprogs := $(sort $(tprogs-y))
+
+# C code
+# Executables compiled from a single .c file
+tprog-csingle := $(foreach m,$(__tprogs), \
+ $(if $($(m)-objs),,$(m)))
+
+# C executables linked based on several .o files
+tprog-cmulti := $(foreach m,$(__tprogs),\
+ $(if $($(m)-objs),$(m)))
+
+# Object (.o) files compiled from .c files
+tprog-cobjs := $(sort $(foreach m,$(__tprogs),$($(m)-objs)))
+
+tprog-csingle := $(addprefix $(obj)/,$(tprog-csingle))
+tprog-cmulti := $(addprefix $(obj)/,$(tprog-cmulti))
+tprog-cobjs := $(addprefix $(obj)/,$(tprog-cobjs))
+
+#####
+# Handle options to gcc. Support building with separate output directory
+
+_tprogc_flags = $(TPROGS_CFLAGS) \
+ $(TPROGCFLAGS_$(basetarget).o)
+
+# $(objtree)/$(obj) for including generated headers from checkin source files
+ifeq ($(KBUILD_EXTMOD),)
+ifdef building_out_of_srctree
+_tprogc_flags += -I $(objtree)/$(obj)
+endif
+endif
+
+tprogc_flags = -Wp,-MD,$(depfile) $(_tprogc_flags)
+
+# Create executable from a single .c file
+# tprog-csingle -> Executable
+quiet_cmd_tprog-csingle = CC $@
+ cmd_tprog-csingle = $(CC) $(tprogc_flags) $(TPROGS_LDFLAGS) -o $@ $< \
+ $(TPROGS_LDLIBS) $(TPROGLDLIBS_$(@F))
+$(tprog-csingle): $(obj)/%: $(src)/%.c FORCE
+ $(call if_changed_dep,tprog-csingle)
+
+# Link an executable based on list of .o files, all plain c
+# tprog-cmulti -> executable
+quiet_cmd_tprog-cmulti = LD $@
+ cmd_tprog-cmulti = $(CC) $(tprogc_flags) $(TPROGS_LDFLAGS) -o $@ \
+ $(addprefix $(obj)/,$($(@F)-objs)) \
+ $(TPROGS_LDLIBS) $(TPROGLDLIBS_$(@F))
+$(tprog-cmulti): $(tprog-cobjs) FORCE
+ $(call if_changed,tprog-cmulti)
+$(call multi_depend, $(tprog-cmulti), , -objs)
+
+# Create .o file from a single .c file
+# tprog-cobjs -> .o
+quiet_cmd_tprog-cobjs = CC $@
+ cmd_tprog-cobjs = $(CC) $(tprogc_flags) -c -o $@ $<
+$(tprog-cobjs): $(obj)/%.o: $(src)/%.c FORCE
+ $(call if_changed_dep,tprog-cobjs)
--
2.17.1

2019-10-09 20:44:35

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 02/15] samples/bpf: fix cookie_uid_helper_example obj build

Don't list userspace "cookie_uid_helper_example" object in list for
bpf objects.

'always' target is used for listing bpf programs, but
'cookie_uid_helper_example.o' is a user space ELF file, and covered
by rule `per_socket_stats_example`, so shouldn't be in 'always'.
Let us remove `always += cookie_uid_helper_example.o`, which avoids
breaking cross compilation due to mismatched includes.

Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 1 -
1 file changed, 1 deletion(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 4f61725b1d86..045fa43842e6 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -145,7 +145,6 @@ always += sampleip_kern.o
always += lwt_len_hist_kern.o
always += xdp_tx_iptunnel_kern.o
always += test_map_in_map_kern.o
-always += cookie_uid_helper_example.o
always += tcp_synrto_kern.o
always += tcp_rwnd_kern.o
always += tcp_bufs_kern.o
--
2.17.1

2019-10-09 20:45:10

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 10/15] samples/bpf: use target CC environment for HDR_PROBE

No need in hacking HOSTCC to be cross-compiler any more, so drop
this trick and use target CC for HDR_PROBE.

Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 57a15ff938a6..a6c33496e8ca 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -205,15 +205,14 @@ BTF_PAHOLE ?= pahole

# Detect that we're cross compiling and use the cross compiler
ifdef CROSS_COMPILE
-HOSTCC = $(CROSS_COMPILE)gcc
CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
endif

# Don't evaluate probes and warnings if we need to run make recursively
ifneq ($(src),)
HDR_PROBE := $(shell printf "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
- $(HOSTCC) $(KBUILD_HOSTCFLAGS) -x c - -o /dev/null 2>/dev/null && \
- echo okay)
+ $(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
+ -o /dev/null 2>/dev/null && echo okay)

ifeq ($(HDR_PROBE),)
$(warning WARNING: Detected possible issues with include path.)
--
2.17.1

2019-10-09 20:46:15

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 01/15] samples/bpf: fix HDR_PROBE "echo"

echo should be replaced with echo -e to handle '\n' correctly, but
instead, replace it with printf as some systems can't handle echo -e.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index a11d7270583d..4f61725b1d86 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -201,7 +201,7 @@ endif

# Don't evaluate probes and warnings if we need to run make recursively
ifneq ($(src),)
-HDR_PROBE := $(shell echo "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
+HDR_PROBE := $(shell printf "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
$(HOSTCC) $(KBUILD_HOSTCFLAGS) -x c - -o /dev/null 2>/dev/null && \
echo okay)

--
2.17.1

2019-10-09 20:46:22

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 05/15] samples/bpf: use __LINUX_ARM_ARCH__ selector for arm

For arm, -D__LINUX_ARM_ARCH__=X is min version used as instruction
set selector and is absolutely required while parsing some parts of
headers. It's present in KBUILD_CFLAGS but not in autoconf.h, so let's
retrieve it from and add to programs cflags. In another case errors
like "SMP is not supported" for armv7 and bunch of other errors are
issued resulting to incorrect final object.
---
samples/bpf/Makefile | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index cf882e43648a..9b33e7395eac 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -185,6 +185,14 @@ HOSTLDLIBS_map_perf_test += -lrt
HOSTLDLIBS_test_overhead += -lrt
HOSTLDLIBS_xdpsock += -pthread

+ifeq ($(ARCH), arm)
+# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
+# headers when arm instruction set identification is requested.
+ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
+BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
+KBUILD_HOSTCFLAGS += $(ARM_ARCH_SELECTOR)
+endif
+
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
LLC ?= llc
--
2.17.1

2019-10-09 20:46:21

by Ivan Khoronzhuk

[permalink] [raw]
Subject: [PATCH v4 bpf-next 08/15] samples/bpf: base target programs rules on Makefile.target

The main reason for that - HOSTCC and CC have different aims.
HOSTCC is used to build programs running on host, that can
cross-comple target programs with CC. It was tested for arm and arm64
cross compilation, based on linaro toolchain, but should work for
others.

So, in order to split cross compilation (CC) with host build (HOSTCC),
lets base samples on Makefile.target. It allows to cross-compile
samples/bpf programs with CC while auxialry tools running on host
built with HOSTCC.

Signed-off-by: Ivan Khoronzhuk <[email protected]>
---
samples/bpf/Makefile | 135 ++++++++++++++++++++++---------------------
1 file changed, 69 insertions(+), 66 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index bb2d976e824e..91bfb421c278 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -4,55 +4,53 @@ BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools

# List of programs to build
-hostprogs-y := test_lru_dist
-hostprogs-y += sock_example
-hostprogs-y += fds_example
-hostprogs-y += sockex1
-hostprogs-y += sockex2
-hostprogs-y += sockex3
-hostprogs-y += tracex1
-hostprogs-y += tracex2
-hostprogs-y += tracex3
-hostprogs-y += tracex4
-hostprogs-y += tracex5
-hostprogs-y += tracex6
-hostprogs-y += tracex7
-hostprogs-y += test_probe_write_user
-hostprogs-y += trace_output
-hostprogs-y += lathist
-hostprogs-y += offwaketime
-hostprogs-y += spintest
-hostprogs-y += map_perf_test
-hostprogs-y += test_overhead
-hostprogs-y += test_cgrp2_array_pin
-hostprogs-y += test_cgrp2_attach
-hostprogs-y += test_cgrp2_sock
-hostprogs-y += test_cgrp2_sock2
-hostprogs-y += xdp1
-hostprogs-y += xdp2
-hostprogs-y += xdp_router_ipv4
-hostprogs-y += test_current_task_under_cgroup
-hostprogs-y += trace_event
-hostprogs-y += sampleip
-hostprogs-y += tc_l2_redirect
-hostprogs-y += lwt_len_hist
-hostprogs-y += xdp_tx_iptunnel
-hostprogs-y += test_map_in_map
-hostprogs-y += per_socket_stats_example
-hostprogs-y += xdp_redirect
-hostprogs-y += xdp_redirect_map
-hostprogs-y += xdp_redirect_cpu
-hostprogs-y += xdp_monitor
-hostprogs-y += xdp_rxq_info
-hostprogs-y += syscall_tp
-hostprogs-y += cpustat
-hostprogs-y += xdp_adjust_tail
-hostprogs-y += xdpsock
-hostprogs-y += xdp_fwd
-hostprogs-y += task_fd_query
-hostprogs-y += xdp_sample_pkts
-hostprogs-y += ibumad
-hostprogs-y += hbm
+tprogs-y := test_lru_dist
+tprogs-y += sock_example
+tprogs-y += fds_example
+tprogs-y += sockex1
+tprogs-y += sockex2
+tprogs-y += sockex3
+tprogs-y += tracex1
+tprogs-y += tracex2
+tprogs-y += tracex3
+tprogs-y += tracex4
+tprogs-y += tracex5
+tprogs-y += tracex6
+tprogs-y += tracex7
+tprogs-y += test_probe_write_user
+tprogs-y += trace_output
+tprogs-y += lathist
+tprogs-y += offwaketime
+tprogs-y += spintest
+tprogs-y += map_perf_test
+tprogs-y += test_overhead
+tprogs-y += test_cgrp2_array_pin
+tprogs-y += test_cgrp2_attach
+tprogs-y += test_cgrp2_sock
+tprogs-y += test_cgrp2_sock2
+tprogs-y += xdp1
+tprogs-y += xdp2
+tprogs-y += xdp_router_ipv4
+tprogs-y += test_current_task_under_cgroup
+tprogs-y += trace_event
+tprogs-y += sampleip
+tprogs-y += tc_l2_redirect
+tprogs-y += lwt_len_hist
+tprogs-y += xdp_tx_iptunnel
+tprogs-y += test_map_in_map
+tprogs-y += xdp_redirect_map
+tprogs-y += xdp_redirect_cpu
+tprogs-y += xdp_monitor
+tprogs-y += xdp_rxq_info
+tprogs-y += syscall_tp
+tprogs-y += cpustat
+tprogs-y += xdp_adjust_tail
+tprogs-y += xdpsock
+tprogs-y += xdp_fwd
+tprogs-y += task_fd_query
+tprogs-y += xdp_sample_pkts
+tprogs-y += ibumad
+tprogs-y += hbm

# Libbpf dependencies
LIBBPF = $(TOOLS_PATH)/lib/bpf/libbpf.a
@@ -111,7 +109,7 @@ ibumad-objs := bpf_load.o ibumad_user.o $(TRACE_HELPERS)
hbm-objs := bpf_load.o hbm.o $(CGROUP_HELPERS)

# Tell kbuild to always build the programs
-always := $(hostprogs-y)
+always := $(tprogs-y)
always += sockex1_kern.o
always += sockex2_kern.o
always += sockex3_kern.o
@@ -170,29 +168,32 @@ always += ibumad_kern.o
always += hbm_out_kern.o
always += hbm_edt_kern.o

-KBUILD_HOSTCFLAGS += -I$(objtree)/usr/include
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib/bpf/
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib/ -I$(srctree)/tools/include
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/perf
-
-HOSTCFLAGS_bpf_load.o += -Wno-unused-variable
-
-KBUILD_HOSTLDLIBS += $(LIBBPF) -lelf
-HOSTLDLIBS_tracex4 += -lrt
-HOSTLDLIBS_trace_output += -lrt
-HOSTLDLIBS_map_perf_test += -lrt
-HOSTLDLIBS_test_overhead += -lrt
-HOSTLDLIBS_xdpsock += -pthread
-
ifeq ($(ARCH), arm)
# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
# headers when arm instruction set identification is requested.
ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
-KBUILD_HOSTCFLAGS += $(ARM_ARCH_SELECTOR)
+TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
endif

+TPROGS_LDLIBS := $(KBUILD_HOSTLDLIBS)
+TPROGS_CFLAGS += $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS)
+TPROGS_CFLAGS += -I$(objtree)/usr/include
+TPROGS_CFLAGS += -I$(srctree)/tools/lib/bpf/
+TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
+TPROGS_CFLAGS += -I$(srctree)/tools/lib/
+TPROGS_CFLAGS += -I$(srctree)/tools/include
+TPROGS_CFLAGS += -I$(srctree)/tools/perf
+
+TPROGCFLAGS_bpf_load.o += -Wno-unused-variable
+
+TPROGS_LDLIBS += $(LIBBPF) -lelf
+TPROGLDLIBS_tracex4 += -lrt
+TPROGLDLIBS_trace_output += -lrt
+TPROGLDLIBS_map_perf_test += -lrt
+TPROGLDLIBS_test_overhead += -lrt
+TPROGLDLIBS_xdpsock += -pthread
+
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
LLC ?= llc
@@ -283,6 +284,8 @@ $(obj)/hbm_out_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
$(obj)/hbm.o: $(src)/hbm.h
$(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h

+-include $(BPF_SAMPLES_PATH)/Makefile.target
+
# 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.
--
2.17.1

2019-10-09 22:44:38

by Andrii Nakryiko

[permalink] [raw]
Subject: Re: [PATCH v4 bpf-next 01/15] samples/bpf: fix HDR_PROBE "echo"

On Wed, Oct 9, 2019 at 1:45 PM Ivan Khoronzhuk
<[email protected]> wrote:
>
> echo should be replaced with echo -e to handle '\n' correctly, but
> instead, replace it with printf as some systems can't handle echo -e.
>
> Signed-off-by: Ivan Khoronzhuk <[email protected]>
> ---

Acked-by: Andrii Nakryiko <[email protected]>

> samples/bpf/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index a11d7270583d..4f61725b1d86 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -201,7 +201,7 @@ endif
>
> # Don't evaluate probes and warnings if we need to run make recursively
> ifneq ($(src),)
> -HDR_PROBE := $(shell echo "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
> +HDR_PROBE := $(shell printf "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
> $(HOSTCC) $(KBUILD_HOSTCFLAGS) -x c - -o /dev/null 2>/dev/null && \
> echo okay)
>
> --
> 2.17.1
>

2019-10-10 00:27:19

by Andrii Nakryiko

[permalink] [raw]
Subject: Re: [PATCH v4 bpf-next 11/15] libbpf: don't use cxx to test_libpf target

On Wed, Oct 9, 2019 at 1:43 PM Ivan Khoronzhuk
<[email protected]> wrote:
>
> No need to use C++ for test_libbpf target when libbpf is on C and it
> can be tested with C, after this change the CXXFLAGS in makefiles can
> be avoided, at least in bpf samples, when sysroot is used, passing
> same C/LDFLAGS as for lib.
>
> Add "return 0" in test_libbpf to void warn, but also remove spaces at
> start of the lines to keep same style and avoid warns while apply.
>
> Signed-off-by: Ivan Khoronzhuk <[email protected]>
> ---

Thanks for the clean up!

Acked-by: Andrii Nakryiko <[email protected]>

[...]

2019-10-11 00:01:30

by Daniel Borkmann

[permalink] [raw]
Subject: Re: [PATCH v4 bpf-next 00/15] samples: bpf: improve/fix cross-compilation

On Wed, Oct 09, 2019 at 11:41:19PM +0300, Ivan Khoronzhuk wrote:
> This series contains mainly fixes/improvements for cross-compilation
> but not only, tested for arm, arm64, and intended for any arch.
> Also verified on native build (not cross compilation) for x86_64
> and arm, arm64.
[...]

There are multiple SOBs missing, please fix. Thanks!

[...]
5 files changed, 218 insertions(+), 99 deletions(-)
create mode 100644 samples/bpf/Makefile.target
rename tools/lib/bpf/{test_libbpf.cpp => test_libbpf.c} (61%)
Deleted branch mbox (was 9f35d1d0c8f0).
Commit 9f35d1d0c8f0 ("samples/bpf: Add preparation steps and sysroot info to readme")
author Signed-off-by missing
committer Signed-off-by missing
author email: [email protected]
committer email: [email protected]


Commit 1878c1de4607 ("samples/bpf: Use __LINUX_ARM_ARCH__ selector for arm")
author Signed-off-by missing
committer Signed-off-by missing
author email: [email protected]
committer email: [email protected]


Errors in tree with Signed-off-by, please fix!

2019-10-11 00:33:41

by Ivan Khoronzhuk

[permalink] [raw]
Subject: Re: [PATCH v4 bpf-next 00/15] samples: bpf: improve/fix cross-compilation

On Fri, Oct 11, 2019 at 02:00:56AM +0200, Daniel Borkmann wrote:
>On Wed, Oct 09, 2019 at 11:41:19PM +0300, Ivan Khoronzhuk wrote:
>> This series contains mainly fixes/improvements for cross-compilation
>> but not only, tested for arm, arm64, and intended for any arch.
>> Also verified on native build (not cross compilation) for x86_64
>> and arm, arm64.
>[...]
>
>There are multiple SOBs missing, please fix. Thanks!
>
>[...]
> 5 files changed, 218 insertions(+), 99 deletions(-)
> create mode 100644 samples/bpf/Makefile.target
> rename tools/lib/bpf/{test_libbpf.cpp => test_libbpf.c} (61%)
>Deleted branch mbox (was 9f35d1d0c8f0).
>Commit 9f35d1d0c8f0 ("samples/bpf: Add preparation steps and sysroot info to readme")
> author Signed-off-by missing
> committer Signed-off-by missing
> author email: [email protected]
> committer email: [email protected]
>
>
>Commit 1878c1de4607 ("samples/bpf: Use __LINUX_ARM_ARCH__ selector for arm")
> author Signed-off-by missing
> committer Signed-off-by missing
> author email: [email protected]
> committer email: [email protected]
>
>
>Errors in tree with Signed-off-by, please fix!

Done.

--
Regards,
Ivan Khoronzhuk