linux/tools/build/Makefile.feature
Jiri Olsa 739c9180cf perf build: Stop using __weak bpf_object__next_map() to handle older libbpf versions
By adding a feature test for bpf_object__next_map() and providing a fallback if
it isn't present in older versions of libbpf.

Committer testing:

  $ rpm -q libbpf-devel
  libbpf-devel-0.4.0-2.fc35.x86_64
  $ make -C tools/perf LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
  $ cat /tmp/build/perf/feature/test-libbpf-bpf_object__next_map.make.output
  test-libbpf-bpf_object__next_map.c: In function ‘main’:
  test-libbpf-bpf_object__next_map.c:6:9: error: implicit declaration of function ‘bpf_object__next_map’; did you mean ‘bpf_object__next’? [-Werror=implicit-function-declaration]
      6 |         bpf_object__next_map(NULL /* obj */, NULL /* prev */);
        |         ^~~~~~~~~~~~~~~~~~~~
        |         bpf_object__next
    cc1: all warnings being treated as errors
  $
  $ objdump -dS /tmp/build/perf/perf | grep '<bpf_object__next_map>:' -A20
  00000000005b2e00 <bpf_object__next_map>:
  {
    5b2e00:	55                   	push   %rbp
    5b2e01:	48 89 e5             	mov    %rsp,%rbp
    5b2e04:	48 83 ec 10          	sub    $0x10,%rsp
    5b2e08:	64 48 8b 04 25 28 00 	mov    %fs:0x28,%rax
    5b2e0f:	00 00
    5b2e11:	48 89 45 f8          	mov    %rax,-0x8(%rbp)
    5b2e15:	31 c0                	xor    %eax,%eax
	  return bpf_map__next(prev, obj);
    5b2e17:	48 8b 45 f8          	mov    -0x8(%rbp),%rax
    5b2e1b:	64 48 2b 04 25 28 00 	sub    %fs:0x28,%rax
    5b2e22:	00 00
    5b2e24:	75 0f                	jne    5b2e35 <bpf_object__next_map+0x35>
  }
    5b2e26:	c9                   	leave
    5b2e27:	49 89 f8             	mov    %rdi,%r8
    5b2e2a:	48 89 f7             	mov    %rsi,%rdi
	  return bpf_map__next(prev, obj);
    5b2e2d:	4c 89 c6             	mov    %r8,%rsi
    5b2e30:	e9 cb b1 e5 ff       	jmp    40e000 <bpf_map__next@plt>
  $

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/linux-perf-users/YozLKby7ITEtchC9@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-05-26 11:02:02 -03:00

267 lines
8.6 KiB
Gherkin

# SPDX-License-Identifier: GPL-2.0-only
feature_dir := $(srctree)/tools/build/feature
ifneq ($(OUTPUT),)
OUTPUT_FEATURES = $(OUTPUT)feature/
$(shell mkdir -p $(OUTPUT_FEATURES))
endif
feature_check = $(eval $(feature_check_code))
define feature_check_code
feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CC="$(CC)" CXX="$(CXX)" CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
endef
feature_set = $(eval $(feature_set_code))
define feature_set_code
feature-$(1) := 1
endef
#
# Build the feature check binaries in parallel, ignore errors, ignore return value and suppress output:
#
#
# Note that this is not a complete list of all feature tests, just
# those that are typically built on a fully configured system.
#
# [ Feature tests not mentioned here have to be built explicitly in
# the rule that uses them - an example for that is the 'bionic'
# feature check. ]
#
FEATURE_TESTS_BASIC := \
backtrace \
dwarf \
dwarf_getlocations \
eventfd \
fortify-source \
get_current_dir_name \
gettid \
glibc \
libbfd \
libbfd-buildid \
libcap \
libelf \
libelf-getphdrnum \
libelf-gelf_getnote \
libelf-getshdrstrndx \
libnuma \
numa_num_possible_cpus \
libperl \
libpython \
libslang \
libslang-include-subdir \
libtraceevent \
libtracefs \
libcrypto \
libunwind \
pthread-attr-setaffinity-np \
pthread-barrier \
reallocarray \
stackprotector-all \
timerfd \
libdw-dwarf-unwind \
zlib \
lzma \
get_cpuid \
bpf \
sched_getcpu \
sdt \
setns \
libaio \
libzstd \
disassembler-four-args \
file-handle
# FEATURE_TESTS_BASIC + FEATURE_TESTS_EXTRA is the complete list
# of all feature tests
FEATURE_TESTS_EXTRA := \
bionic \
compile-32 \
compile-x32 \
cplus-demangle \
gtk2 \
gtk2-infobar \
hello \
libbabeltrace \
libbfd-liberty \
libbfd-liberty-z \
libopencsd \
libunwind-x86 \
libunwind-x86_64 \
libunwind-arm \
libunwind-aarch64 \
libunwind-debug-frame \
libunwind-debug-frame-arm \
libunwind-debug-frame-aarch64 \
cxx \
llvm \
llvm-version \
clang \
libbpf \
libbpf-btf__load_from_kernel_by_id \
libbpf-bpf_prog_load \
libbpf-bpf_object__next_program \
libbpf-bpf_object__next_map \
libpfm4 \
libdebuginfod \
clang-bpf-co-re
FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC)
ifeq ($(FEATURE_TESTS),all)
FEATURE_TESTS := $(FEATURE_TESTS_BASIC) $(FEATURE_TESTS_EXTRA)
endif
FEATURE_DISPLAY ?= \
dwarf \
dwarf_getlocations \
glibc \
libbfd \
libbfd-buildid \
libcap \
libelf \
libnuma \
numa_num_possible_cpus \
libperl \
libpython \
libcrypto \
libunwind \
libdw-dwarf-unwind \
zlib \
lzma \
get_cpuid \
bpf \
libaio \
libzstd \
disassembler-four-args
# Set FEATURE_CHECK_(C|LD)FLAGS-all for all FEATURE_TESTS features.
# If in the future we need per-feature checks/flags for features not
# mentioned in this list we need to refactor this ;-).
set_test_all_flags = $(eval $(set_test_all_flags_code))
define set_test_all_flags_code
FEATURE_CHECK_CFLAGS-all += $(FEATURE_CHECK_CFLAGS-$(1))
FEATURE_CHECK_LDFLAGS-all += $(FEATURE_CHECK_LDFLAGS-$(1))
endef
$(foreach feat,$(FEATURE_TESTS),$(call set_test_all_flags,$(feat)))
#
# Special fast-path for the 'all features are available' case:
#
$(call feature_check,all,$(MSG))
#
# Just in case the build freshly failed, make sure we print the
# feature matrix:
#
ifeq ($(feature-all), 1)
#
# test-all.c passed - just set all the core feature flags to 1:
#
$(foreach feat,$(FEATURE_TESTS),$(call feature_set,$(feat)))
#
# test-all.c does not comprise these tests, so we need to
# for this case to get features proper values
#
$(call feature_check,compile-32)
$(call feature_check,compile-x32)
$(call feature_check,bionic)
$(call feature_check,libbabeltrace)
else
$(foreach feat,$(FEATURE_TESTS),$(call feature_check,$(feat)))
endif
#
# Print the result of the feature test:
#
feature_print_status = $(eval $(feature_print_status_code)) $(info $(MSG))
define feature_print_status_code
ifeq ($(feature-$(1)), 1)
MSG = $(shell printf '...%30s: [ \033[32mon\033[m ]' $(1))
else
MSG = $(shell printf '...%30s: [ \033[31mOFF\033[m ]' $(1))
endif
endef
feature_print_text = $(eval $(feature_print_text_code)) $(info $(MSG))
define feature_print_text_code
MSG = $(shell printf '...%30s: %s' $(1) $(2))
endef
#
# generates feature value assignment for name, like:
# $(call feature_assign,dwarf) == feature-dwarf=1
#
feature_assign = feature-$(1)=$(feature-$(1))
FEATURE_DUMP_FILENAME = $(OUTPUT)FEATURE-DUMP$(FEATURE_USER)
FEATURE_DUMP := $(shell touch $(FEATURE_DUMP_FILENAME); cat $(FEATURE_DUMP_FILENAME))
feature_dump_check = $(eval $(feature_dump_check_code))
define feature_dump_check_code
ifeq ($(findstring $(1),$(FEATURE_DUMP)),)
$(2) := 1
endif
endef
#
# First check if any test from FEATURE_DISPLAY
# and set feature_display := 1 if it does
$(foreach feat,$(FEATURE_DISPLAY),$(call feature_dump_check,$(call feature_assign,$(feat)),feature_display))
#
# Now also check if any other test changed,
# so we force FEATURE-DUMP generation
$(foreach feat,$(FEATURE_TESTS),$(call feature_dump_check,$(call feature_assign,$(feat)),feature_dump_changed))
# The $(feature_display) controls the default detection message
# output. It's set if:
# - detected features differes from stored features from
# last build (in $(FEATURE_DUMP_FILENAME) file)
# - one of the $(FEATURE_DISPLAY) is not detected
# - VF is enabled
ifeq ($(feature_dump_changed),1)
$(shell rm -f $(FEATURE_DUMP_FILENAME))
$(foreach feat,$(FEATURE_TESTS),$(shell echo "$(call feature_assign,$(feat))" >> $(FEATURE_DUMP_FILENAME)))
endif
feature_display_check = $(eval $(feature_check_display_code))
define feature_check_display_code
ifneq ($(feature-$(1)), 1)
feature_display := 1
endif
endef
$(foreach feat,$(FEATURE_DISPLAY),$(call feature_display_check,$(feat)))
ifeq ($(VF),1)
feature_display := 1
feature_verbose := 1
endif
feature_display_entries = $(eval $(feature_display_entries_code))
define feature_display_entries_code
ifeq ($(feature_display),1)
$(info )
$(info Auto-detecting system features:)
$(foreach feat,$(FEATURE_DISPLAY),$(call feature_print_status,$(feat),))
ifneq ($(feature_verbose),1)
$(info )
endif
endif
ifeq ($(feature_verbose),1)
TMP := $(filter-out $(FEATURE_DISPLAY),$(FEATURE_TESTS))
$(foreach feat,$(TMP),$(call feature_print_status,$(feat),))
$(info )
endif
endef
ifeq ($(FEATURE_DISPLAY_DEFERRED),)
$(call feature_display_entries)
endif