linux/tools/bpf/bpftool/Makefile

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# SPDX-License-Identifier: GPL-2.0-only
include ../../scripts/Makefile.include
include ../../scripts/utilities.mak
ifeq ($(srctree),)
srctree := $(patsubst %/,%,$(dir $(CURDIR)))
srctree := $(patsubst %/,%,$(dir $(srctree)))
srctree := $(patsubst %/,%,$(dir $(srctree)))
endif
ifeq ($(V),1)
Q =
else
Q = @
endif
BPF_DIR = $(srctree)/tools/lib/bpf/
ifneq ($(OUTPUT),)
tools: bpftool: improve and check builds for different make invocations There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O=<dir> $ make -C tools/bpf/bpftool OUTPUT=<dir> $ make -C tools/bpf/bpftool O=<dir> $ cd tools/ && make bpf O=<dir> $ cd tools/bpf/bpftool && make OUTPUT=<dir> $ cd tools/bpf/bpftool && make O=<dir> After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT=<dir> $ cd tools/ && make bpf OUTPUT=<dir> In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-30 19:00:38 +08:00
LIBBPF_OUTPUT = $(OUTPUT)/libbpf/
LIBBPF_PATH = $(LIBBPF_OUTPUT)
else
tools: bpftool: improve and check builds for different make invocations There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O=<dir> $ make -C tools/bpf/bpftool OUTPUT=<dir> $ make -C tools/bpf/bpftool O=<dir> $ cd tools/ && make bpf O=<dir> $ cd tools/bpf/bpftool && make OUTPUT=<dir> $ cd tools/bpf/bpftool && make O=<dir> After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT=<dir> $ cd tools/ && make bpf OUTPUT=<dir> In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-30 19:00:38 +08:00
LIBBPF_PATH = $(BPF_DIR)
endif
tools: bpftool: improve and check builds for different make invocations There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O=<dir> $ make -C tools/bpf/bpftool OUTPUT=<dir> $ make -C tools/bpf/bpftool O=<dir> $ cd tools/ && make bpf O=<dir> $ cd tools/bpf/bpftool && make OUTPUT=<dir> $ cd tools/bpf/bpftool && make O=<dir> After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT=<dir> $ cd tools/ && make bpf OUTPUT=<dir> In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-30 19:00:38 +08:00
LIBBPF = $(LIBBPF_PATH)libbpf.a
BPFTOOL_VERSION ?= $(shell make -rR --no-print-directory -sC ../../.. kernelversion)
$(LIBBPF): FORCE
tools: bpftool: improve and check builds for different make invocations There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O=<dir> $ make -C tools/bpf/bpftool OUTPUT=<dir> $ make -C tools/bpf/bpftool O=<dir> $ cd tools/ && make bpf O=<dir> $ cd tools/bpf/bpftool && make OUTPUT=<dir> $ cd tools/bpf/bpftool && make O=<dir> After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT=<dir> $ cd tools/ && make bpf OUTPUT=<dir> In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-30 19:00:38 +08:00
$(if $(LIBBPF_OUTPUT),@mkdir -p $(LIBBPF_OUTPUT))
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) $(LIBBPF_OUTPUT)libbpf.a
$(LIBBPF)-clean:
$(call QUIET_CLEAN, libbpf)
tools: bpftool: improve and check builds for different make invocations There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O=<dir> $ make -C tools/bpf/bpftool OUTPUT=<dir> $ make -C tools/bpf/bpftool O=<dir> $ cd tools/ && make bpf O=<dir> $ cd tools/bpf/bpftool && make OUTPUT=<dir> $ cd tools/bpf/bpftool && make O=<dir> After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT=<dir> $ cd tools/ && make bpf OUTPUT=<dir> In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-30 19:00:38 +08:00
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) clean >/dev/null
prefix ?= /usr/local
bash_compdir ?= /usr/share/bash-completion/completions
CFLAGS += -O2
CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers
tools/bpftool: Turn off -Wnested-externs warning Turn off -Wnested-externs to avoid annoying warnings in BUILD_BUG_ON macro when compiling bpftool: In file included from /data/users/andriin/linux/tools/include/linux/build_bug.h:5, from /data/users/andriin/linux/tools/include/linux/kernel.h:8, from /data/users/andriin/linux/kernel/bpf/disasm.h:10, from /data/users/andriin/linux/kernel/bpf/disasm.c:8: /data/users/andriin/linux/kernel/bpf/disasm.c: In function ‘__func_get_name’: /data/users/andriin/linux/tools/include/linux/compiler.h:37:38: warning: nested extern declaration of ‘__compiletime_assert_0’ [-Wnested-externs] _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~~~ /data/users/andriin/linux/tools/include/linux/compiler.h:16:15: note: in definition of macro ‘__compiletime_assert’ extern void prefix ## suffix(void) __compiletime_error(msg); \ ^~~~~~ /data/users/andriin/linux/tools/include/linux/compiler.h:37:2: note: in expansion of macro ‘_compiletime_assert’ _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ /data/users/andriin/linux/tools/include/linux/build_bug.h:39:37: note: in expansion of macro ‘compiletime_assert’ #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ /data/users/andriin/linux/tools/include/linux/build_bug.h:50:2: note: in expansion of macro ‘BUILD_BUG_ON_MSG’ BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) ^~~~~~~~~~~~~~~~ /data/users/andriin/linux/kernel/bpf/disasm.c:20:2: note: in expansion of macro ‘BUILD_BUG_ON’ BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID); ^~~~~~~~~~~~ Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200701212816.2072340-1-andriin@fb.com
2020-07-02 05:28:16 +08:00
CFLAGS += $(filter-out -Wswitch-enum -Wnested-externs,$(EXTRA_WARNINGS))
CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
-I$(if $(OUTPUT),$(OUTPUT),.) \
-I$(srctree)/kernel/bpf/ \
-I$(srctree)/tools/include \
-I$(srctree)/tools/include/uapi \
-I$(srctree)/tools/lib \
-I$(srctree)/tools/perf
CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
ifneq ($(EXTRA_CFLAGS),)
CFLAGS += $(EXTRA_CFLAGS)
endif
ifneq ($(EXTRA_LDFLAGS),)
LDFLAGS += $(EXTRA_LDFLAGS)
endif
INSTALL ?= install
RM ?= rm -f
bpftool: Introduce "prog profile" command With fentry/fexit programs, it is possible to profile BPF program with hardware counters. Introduce bpftool "prog profile", which measures key metrics of a BPF program. bpftool prog profile command creates per-cpu perf events. Then it attaches fentry/fexit programs to the target BPF program. The fentry program saves perf event value to a map. The fexit program reads the perf event again, and calculates the difference, which is the instructions/cycles used by the target program. Example input and output: ./bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) This command measures cycles and instructions for BPF program with id 337 for 3 seconds. The program has triggered 4228 times. The rest of the output is similar to perf-stat. In this example, the counters were only counting ~84% of the time because of time multiplexing of perf counters. Note that, this approach measures cycles and instructions in very small increments. So the fentry/fexit programs introduce noticeable errors to the measurement results. The fentry/fexit programs are generated with BPF skeletons. Therefore, we build bpftool twice. The first time _bpftool is built without skeletons. Then, _bpftool is used to generate the skeletons. The second time, bpftool is built with skeletons. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200309173218.2739965-2-songliubraving@fb.com
2020-03-10 01:32:15 +08:00
CLANG ?= clang
LLVM_STRIP ?= llvm-strip
FEATURE_USER = .bpftool
FEATURE_TESTS = libbfd disassembler-four-args reallocarray zlib libcap \
clang-bpf-co-re
FEATURE_DISPLAY = libbfd disassembler-four-args zlib libcap \
clang-bpf-co-re
check_feat := 1
NON_CHECK_FEAT_TARGETS := clean uninstall doc doc-clean doc-install doc-uninstall
ifdef MAKECMDGOALS
ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
check_feat := 0
endif
endif
ifeq ($(check_feat),1)
ifeq ($(FEATURES_DUMP),)
include $(srctree)/tools/build/Makefile.feature
else
include $(FEATURES_DUMP)
endif
endif
ifeq ($(feature-disassembler-four-args), 1)
CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
endif
ifeq ($(feature-reallocarray), 0)
CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
endif
LIBS = $(LIBBPF) -lelf -lz
ifeq ($(feature-libcap), 1)
CFLAGS += -DUSE_LIBCAP
LIBS += -lcap
endif
include $(wildcard $(OUTPUT)*.d)
all: $(OUTPUT)bpftool
BFD_SRCS = jit_disasm.c
SRCS = $(filter-out $(BFD_SRCS),$(wildcard *.c))
ifeq ($(feature-libbfd),1)
LIBS += -lbfd -ldl -lopcodes
else ifeq ($(feature-libbfd-liberty),1)
LIBS += -lbfd -ldl -lopcodes -liberty
else ifeq ($(feature-libbfd-liberty-z),1)
LIBS += -lbfd -ldl -lopcodes -liberty -lz
endif
ifneq ($(filter -lbfd,$(LIBS)),)
CFLAGS += -DHAVE_LIBBFD_SUPPORT
SRCS += $(BFD_SRCS)
endif
BPFTOOL_BOOTSTRAP := $(if $(OUTPUT),$(OUTPUT)bpftool-bootstrap,./bpftool-bootstrap)
BOOTSTRAP_OBJS = $(addprefix $(OUTPUT),main.o common.o json_writer.o gen.o btf.o)
OBJS = $(patsubst %.c,$(OUTPUT)%.o,$(SRCS)) $(OUTPUT)disasm.o
bpftool: Introduce "prog profile" command With fentry/fexit programs, it is possible to profile BPF program with hardware counters. Introduce bpftool "prog profile", which measures key metrics of a BPF program. bpftool prog profile command creates per-cpu perf events. Then it attaches fentry/fexit programs to the target BPF program. The fentry program saves perf event value to a map. The fexit program reads the perf event again, and calculates the difference, which is the instructions/cycles used by the target program. Example input and output: ./bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) This command measures cycles and instructions for BPF program with id 337 for 3 seconds. The program has triggered 4228 times. The rest of the output is similar to perf-stat. In this example, the counters were only counting ~84% of the time because of time multiplexing of perf counters. Note that, this approach measures cycles and instructions in very small increments. So the fentry/fexit programs introduce noticeable errors to the measurement results. The fentry/fexit programs are generated with BPF skeletons. Therefore, we build bpftool twice. The first time _bpftool is built without skeletons. Then, _bpftool is used to generate the skeletons. The second time, bpftool is built with skeletons. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200309173218.2739965-2-songliubraving@fb.com
2020-03-10 01:32:15 +08:00
VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
$(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
../../../vmlinux \
/sys/kernel/btf/vmlinux \
/boot/vmlinux-$(shell uname -r)
VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
ifneq ($(VMLINUX_BTF)$(VMLINUX_H),)
ifeq ($(feature-clang-bpf-co-re),1)
BUILD_BPF_SKELS := 1
$(OUTPUT)vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL_BOOTSTRAP)
ifeq ($(VMLINUX_H),)
$(QUIET_GEN)$(BPFTOOL_BOOTSTRAP) btf dump file $< format c > $@
else
$(Q)cp "$(VMLINUX_H)" $@
endif
$(OUTPUT)%.bpf.o: skeleton/%.bpf.c $(OUTPUT)vmlinux.h $(LIBBPF)
$(QUIET_CLANG)$(CLANG) \
-I$(if $(OUTPUT),$(OUTPUT),.) \
-I$(srctree)/tools/include/uapi/ \
-I$(LIBBPF_PATH) \
-I$(srctree)/tools/lib \
-g -O2 -target bpf -c $< -o $@ && $(LLVM_STRIP) -g $@
bpftool: Introduce "prog profile" command With fentry/fexit programs, it is possible to profile BPF program with hardware counters. Introduce bpftool "prog profile", which measures key metrics of a BPF program. bpftool prog profile command creates per-cpu perf events. Then it attaches fentry/fexit programs to the target BPF program. The fentry program saves perf event value to a map. The fexit program reads the perf event again, and calculates the difference, which is the instructions/cycles used by the target program. Example input and output: ./bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) This command measures cycles and instructions for BPF program with id 337 for 3 seconds. The program has triggered 4228 times. The rest of the output is similar to perf-stat. In this example, the counters were only counting ~84% of the time because of time multiplexing of perf counters. Note that, this approach measures cycles and instructions in very small increments. So the fentry/fexit programs introduce noticeable errors to the measurement results. The fentry/fexit programs are generated with BPF skeletons. Therefore, we build bpftool twice. The first time _bpftool is built without skeletons. Then, _bpftool is used to generate the skeletons. The second time, bpftool is built with skeletons. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200309173218.2739965-2-songliubraving@fb.com
2020-03-10 01:32:15 +08:00
$(OUTPUT)%.skel.h: $(OUTPUT)%.bpf.o $(BPFTOOL_BOOTSTRAP)
$(QUIET_GEN)$(BPFTOOL_BOOTSTRAP) gen skeleton $< > $@
$(OUTPUT)prog.o: $(OUTPUT)profiler.skel.h
tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs Add bpf_iter-based way to find all the processes that hold open FDs against BPF object (map, prog, link, btf). bpftool always attempts to discover this, but will silently give up if kernel doesn't yet support bpf_iter BPF programs. Process name and PID are emitted for each process (task group). Sample output for each of 4 BPF objects: $ sudo ./bpftool prog show 2694: cgroup_device tag 8c42dee26e8cd4c2 gpl loaded_at 2020-06-16T15:34:32-0700 uid 0 xlated 648B jited 409B memlock 4096B pids systemd(1) 2907: cgroup_skb name egress tag 9ad187367cf2b9e8 gpl loaded_at 2020-06-16T18:06:54-0700 uid 0 xlated 48B jited 59B memlock 4096B map_ids 2436 btf_id 1202 pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool map show 2436: array name test_cgr.bss flags 0x400 key 4B value 8B max_entries 1 memlock 8192B btf_id 1202 pids test_progs(2238417), test_progs(2238445) 2445: array name pid_iter.rodata flags 0x480 key 4B value 4B max_entries 1 memlock 8192B btf_id 1214 frozen pids bpftool(2239612) $ sudo ./bpftool link show 61: cgroup prog 2908 cgroup_id 375301 attach_type egress pids test_progs(2238417), test_progs(2238445) 62: cgroup prog 2908 cgroup_id 375344 attach_type egress pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool btf show 1202: size 1527B prog_ids 2908,2907 map_ids 2436 pids test_progs(2238417), test_progs(2238445) 1242: size 34684B pids bpftool(2258892) Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com
2020-06-20 07:17:02 +08:00
$(OUTPUT)pids.o: $(OUTPUT)pid_iter.skel.h
endif
endif
bpftool: Introduce "prog profile" command With fentry/fexit programs, it is possible to profile BPF program with hardware counters. Introduce bpftool "prog profile", which measures key metrics of a BPF program. bpftool prog profile command creates per-cpu perf events. Then it attaches fentry/fexit programs to the target BPF program. The fentry program saves perf event value to a map. The fexit program reads the perf event again, and calculates the difference, which is the instructions/cycles used by the target program. Example input and output: ./bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) This command measures cycles and instructions for BPF program with id 337 for 3 seconds. The program has triggered 4228 times. The rest of the output is similar to perf-stat. In this example, the counters were only counting ~84% of the time because of time multiplexing of perf counters. Note that, this approach measures cycles and instructions in very small increments. So the fentry/fexit programs introduce noticeable errors to the measurement results. The fentry/fexit programs are generated with BPF skeletons. Therefore, we build bpftool twice. The first time _bpftool is built without skeletons. Then, _bpftool is used to generate the skeletons. The second time, bpftool is built with skeletons. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200309173218.2739965-2-songliubraving@fb.com
2020-03-10 01:32:15 +08:00
CFLAGS += $(if $(BUILD_BPF_SKELS),,-DBPFTOOL_WITHOUT_SKELETONS)
$(OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c
$(QUIET_CC)$(CC) $(CFLAGS) -c -MMD -o $@ $<
$(OUTPUT)feature.o: | zdep
$(BPFTOOL_BOOTSTRAP): $(BOOTSTRAP_OBJS) $(LIBBPF)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(BOOTSTRAP_OBJS) $(LIBS)
$(OUTPUT)bpftool: $(OBJS) $(LIBBPF)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(OBJS) $(LIBS)
$(OUTPUT)%.o: %.c
$(QUIET_CC)$(CC) $(CFLAGS) -c -MMD -o $@ $<
feature-detect-clean:
$(call QUIET_CLEAN, feature-detect)
$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
clean: $(LIBBPF)-clean feature-detect-clean
$(call QUIET_CLEAN, bpftool)
$(Q)$(RM) -- $(OUTPUT)bpftool $(OUTPUT)*.o $(OUTPUT)*.d
$(Q)$(RM) -- $(BPFTOOL_BOOTSTRAP) $(OUTPUT)*.skel.h $(OUTPUT)vmlinux.h
$(Q)$(RM) -r -- $(OUTPUT)libbpf/
$(call QUIET_CLEAN, core-gen)
$(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.bpftool
$(Q)$(RM) -r -- $(OUTPUT)feature/
install: $(OUTPUT)bpftool
$(call QUIET_INSTALL, bpftool)
$(Q)$(INSTALL) -m 0755 -d $(DESTDIR)$(prefix)/sbin
$(Q)$(INSTALL) $(OUTPUT)bpftool $(DESTDIR)$(prefix)/sbin/bpftool
$(Q)$(INSTALL) -m 0755 -d $(DESTDIR)$(bash_compdir)
$(Q)$(INSTALL) -m 0644 bash-completion/bpftool $(DESTDIR)$(bash_compdir)
uninstall:
$(call QUIET_UNINST, bpftool)
$(Q)$(RM) -- $(DESTDIR)$(prefix)/sbin/bpftool
$(Q)$(RM) -- $(DESTDIR)$(bash_compdir)/bpftool
doc:
$(call descend,Documentation)
doc-clean:
$(call descend,Documentation,clean)
doc-install:
$(call descend,Documentation,install)
doc-uninstall:
$(call descend,Documentation,uninstall)
FORCE:
zdep:
@if [ "$(feature-zlib)" != "1" ]; then echo "No zlib found"; exit 1 ; fi
.SECONDARY:
.PHONY: all FORCE clean install uninstall zdep
.PHONY: doc doc-clean doc-install doc-uninstall
.DEFAULT_GOAL := all