1# SPDX-License-Identifier: GPL-2.0-only
2feature_dir := $(srctree)/tools/build/feature
3
4ifneq ($(OUTPUT),)
5  OUTPUT_FEATURES = $(OUTPUT)feature/
6  $(shell mkdir -p $(OUTPUT_FEATURES))
7endif
8
9feature_check = $(eval $(feature_check_code))
10define feature_check_code
11  feature-$(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)
12endef
13
14feature_set = $(eval $(feature_set_code))
15define feature_set_code
16  feature-$(1) := 1
17endef
18
19#
20# Build the feature check binaries in parallel, ignore errors, ignore return value and suppress output:
21#
22
23#
24# Note that this is not a complete list of all feature tests, just
25# those that are typically built on a fully configured system.
26#
27# [ Feature tests not mentioned here have to be built explicitly in
28#   the rule that uses them - an example for that is the 'bionic'
29#   feature check. ]
30#
31# These + the ones in FEATURE_TESTS_EXTRA are included in
32# tools/build/feature/test-all.c and we try to build it all together
33# then setting all those features to '1' meaning they are all enabled.
34#
35# There are things like fortify-source that will be set to 1 because test-all
36# is built with the flags needed to test if its enabled, resulting in
37#
38#   $ rm -rf /tmp/b ; mkdir /tmp/b ; make -C tools/perf O=/tmp/b feature-dump
39#   $ grep fortify-source /tmp/b/FEATURE-DUMP
40#   feature-fortify-source=1
41#   $
42#
43#   All the others should have lines in tools/build/feature/test-all.c like:
44#
45#    #define main main_test_disassembler_init_styled
46#    # include "test-disassembler-init-styled.c"
47#    #undef main
48#
49#    #define main main_test_libzstd
50#    # include "test-libzstd.c"
51#    #undef main
52#
53#    int main(int argc, char *argv[])
54#    {
55#      main_test_disassembler_four_args();
56#      main_test_libzstd();
57#      return 0;
58#    }
59#
60#    If the sample above works, then we end up with these lines in the FEATURE-DUMP
61#    file:
62#
63#    feature-disassembler-four-args=1
64#    feature-libzstd=1
65#
66FEATURE_TESTS_BASIC :=                  \
67        backtrace                       \
68        libdw                           \
69        eventfd                         \
70        fortify-source                  \
71        get_current_dir_name            \
72        gettid				\
73        glibc                           \
74        libbfd                          \
75        libbfd-buildid			\
76        libelf                          \
77        libelf-getphdrnum               \
78        libelf-gelf_getnote             \
79        libelf-getshdrstrndx            \
80        libelf-zstd                     \
81        libnuma                         \
82        numa_num_possible_cpus          \
83        libperl                         \
84        libpython                       \
85        libslang                        \
86        libtraceevent                   \
87        libtracefs                      \
88        libcpupower                     \
89        libcrypto                       \
90        libunwind                       \
91        pthread-attr-setaffinity-np     \
92        pthread-barrier     		\
93        reallocarray                    \
94        stackprotector-all              \
95        timerfd                         \
96        zlib                            \
97        lzma                            \
98        get_cpuid                       \
99        bpf                             \
100        scandirat			\
101        sched_getcpu			\
102        sdt				\
103        setns				\
104        libaio				\
105        libzstd				\
106        disassembler-four-args		\
107        disassembler-init-styled	\
108        file-handle
109
110# FEATURE_TESTS_BASIC + FEATURE_TESTS_EXTRA is the complete list
111# of all feature tests
112FEATURE_TESTS_EXTRA :=                  \
113         bionic                         \
114         compile-32                     \
115         compile-x32                    \
116         cplus-demangle                 \
117         cxa-demangle                   \
118         gtk2                           \
119         gtk2-infobar                   \
120         hello                          \
121         libbabeltrace                  \
122         libcapstone                    \
123         libbfd-liberty                 \
124         libbfd-liberty-z               \
125         libopencsd                     \
126         cxx                            \
127         llvm                           \
128         clang                          \
129         libbpf                         \
130         libbpf-btf__load_from_kernel_by_id \
131         libbpf-bpf_prog_load           \
132         libbpf-bpf_object__next_program \
133         libbpf-bpf_object__next_map    \
134         libbpf-bpf_program__set_insns  \
135         libbpf-bpf_create_map		\
136         libpfm4                        \
137         libdebuginfod			\
138         clang-bpf-co-re
139
140
141FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC)
142
143ifeq ($(FEATURE_TESTS),all)
144  FEATURE_TESTS := $(FEATURE_TESTS_BASIC) $(FEATURE_TESTS_EXTRA)
145endif
146
147FEATURE_DISPLAY ?=              \
148         libdw                  \
149         glibc                  \
150         libbfd                 \
151         libbfd-buildid		\
152         libelf                 \
153         libnuma                \
154         numa_num_possible_cpus \
155         libperl                \
156         libpython              \
157         libcrypto              \
158         libunwind              \
159         libcapstone            \
160         llvm-perf              \
161         zlib                   \
162         lzma                   \
163         get_cpuid              \
164         bpf			\
165         libaio			\
166         libzstd
167
168#
169# Declare group members of a feature to display the logical OR of the detection
170# result instead of each member result.
171#
172FEATURE_GROUP_MEMBERS-libbfd = libbfd-liberty libbfd-liberty-z
173
174#
175# Declare list of feature dependency packages that provide pkg-config files.
176#
177FEATURE_PKG_CONFIG ?=           \
178         libtraceevent          \
179         libtracefs
180
181feature_pkg_config = $(eval $(feature_pkg_config_code))
182define feature_pkg_config_code
183  FEATURE_CHECK_CFLAGS-$(1) := $(shell $(PKG_CONFIG) --cflags $(1) 2>/dev/null)
184  FEATURE_CHECK_LDFLAGS-$(1) := $(shell $(PKG_CONFIG) --libs $(1) 2>/dev/null)
185endef
186
187# Set FEATURE_CHECK_(C|LD)FLAGS-$(package) for packages using pkg-config.
188ifneq ($(PKG_CONFIG),)
189  $(foreach package,$(FEATURE_PKG_CONFIG),$(call feature_pkg_config,$(package)))
190endif
191
192# Set FEATURE_CHECK_(C|LD)FLAGS-all for all FEATURE_TESTS features.
193# If in the future we need per-feature checks/flags for features not
194# mentioned in this list we need to refactor this ;-).
195set_test_all_flags = $(eval $(set_test_all_flags_code))
196define set_test_all_flags_code
197  FEATURE_CHECK_CFLAGS-all  += $(FEATURE_CHECK_CFLAGS-$(1))
198  FEATURE_CHECK_LDFLAGS-all += $(FEATURE_CHECK_LDFLAGS-$(1))
199endef
200
201$(foreach feat,$(FEATURE_TESTS),$(call set_test_all_flags,$(feat)))
202
203#
204# Special fast-path for the 'all features are available' case:
205#
206$(call feature_check,all,$(MSG))
207
208#
209# Just in case the build freshly failed, make sure we print the
210# feature matrix:
211#
212ifeq ($(feature-all), 1)
213  #
214  # test-all.c passed - just set all the core feature flags to 1:
215  #
216  $(foreach feat,$(FEATURE_TESTS),$(call feature_set,$(feat)))
217  #
218  # test-all.c does not comprise these tests, so we need to
219  # for this case to get features proper values
220  #
221  $(call feature_check,compile-32)
222  $(call feature_check,compile-x32)
223  $(call feature_check,bionic)
224  $(call feature_check,libbabeltrace)
225else
226  $(foreach feat,$(FEATURE_TESTS),$(call feature_check,$(feat)))
227endif
228
229#
230# Print the result of the feature test:
231#
232feature_print_status = $(eval $(feature_print_status_code))
233
234feature_group = $(eval $(feature_gen_group)) $(GROUP)
235
236define feature_gen_group
237  GROUP := $(1)
238  ifneq ($(feature_verbose),1)
239    GROUP += $(FEATURE_GROUP_MEMBERS-$(1))
240  endif
241endef
242
243define feature_print_status_code
244  ifneq (,$(filter 1,$(foreach feat,$(call feature_group,$(feat)),$(feature-$(feat)))))
245    MSG = $(shell printf '...%40s: [ \033[32mon\033[m  ]' $(1))
246  else
247    MSG = $(shell printf '...%40s: [ \033[31mOFF\033[m ]' $(1))
248  endif
249endef
250
251feature_print_text = $(eval $(feature_print_text_code))
252define feature_print_text_code
253    MSG = $(shell printf '...%40s: %s' $(1) $(2))
254endef
255
256#
257# generates feature value assignment for name, like:
258#   $(call feature_assign,libdw) == feature-libdw=1
259#
260feature_assign = feature-$(1)=$(feature-$(1))
261
262FEATURE_DUMP_FILENAME = $(OUTPUT)FEATURE-DUMP$(FEATURE_USER)
263FEATURE_DUMP := $(shell touch $(FEATURE_DUMP_FILENAME); cat $(FEATURE_DUMP_FILENAME))
264
265feature_dump_check = $(eval $(feature_dump_check_code))
266define feature_dump_check_code
267  ifeq ($(findstring $(1),$(FEATURE_DUMP)),)
268    $(2) := 1
269  endif
270endef
271
272#
273# First check if any test from FEATURE_DISPLAY
274# and set feature_display := 1 if it does
275$(foreach feat,$(FEATURE_DISPLAY),$(call feature_dump_check,$(call feature_assign,$(feat)),feature_display))
276
277#
278# Now also check if any other test changed,
279# so we force FEATURE-DUMP generation
280$(foreach feat,$(FEATURE_TESTS),$(call feature_dump_check,$(call feature_assign,$(feat)),feature_dump_changed))
281
282# The $(feature_display) controls the default detection message
283# output. It's set if:
284# - detected features differes from stored features from
285#   last build (in $(FEATURE_DUMP_FILENAME) file)
286# - one of the $(FEATURE_DISPLAY) is not detected
287# - VF is enabled
288
289ifeq ($(feature_dump_changed),1)
290  $(shell rm -f $(FEATURE_DUMP_FILENAME))
291  $(foreach feat,$(FEATURE_TESTS),$(shell echo "$(call feature_assign,$(feat))" >> $(FEATURE_DUMP_FILENAME)))
292endif
293
294feature_display_check = $(eval $(feature_check_display_code))
295define feature_check_display_code
296  ifneq ($(feature-$(1)), 1)
297    feature_display := 1
298  endif
299endef
300
301$(foreach feat,$(FEATURE_DISPLAY),$(call feature_display_check,$(feat)))
302
303ifeq ($(VF),1)
304  feature_display := 1
305  feature_verbose := 1
306endif
307
308ifneq ($(feature_verbose),1)
309  #
310  # Determine the features to omit from the displayed message, as only the
311  # logical OR of the detection result will be shown.
312  #
313  FEATURE_OMIT := $(foreach feat,$(FEATURE_DISPLAY),$(FEATURE_GROUP_MEMBERS-$(feat)))
314endif
315
316feature_display_entries = $(eval $(feature_display_entries_code))
317define feature_display_entries_code
318  ifeq ($(feature_display),1)
319    $$(info )
320    $$(info Auto-detecting system features:)
321    $(foreach feat,$(filter-out $(FEATURE_OMIT),$(FEATURE_DISPLAY)),$(call feature_print_status,$(feat),) $$(info $(MSG)))
322  endif
323
324  ifeq ($(feature_verbose),1)
325    $(eval TMP := $(filter-out $(FEATURE_DISPLAY),$(FEATURE_TESTS)))
326    $(foreach feat,$(TMP),$(call feature_print_status,$(feat),) $$(info $(MSG)))
327  endif
328endef
329
330ifeq ($(FEATURE_DISPLAY_DEFERRED),)
331  $(call feature_display_entries)
332  $(info )
333endif
334