History log of /linux-master/tools/build/Makefile.feature
Revision Date Author Comments
# 8b767db3 17-Feb-2024 Changbin Du <changbin.du@huawei.com>

perf: build: introduce the libcapstone

Later we will use libcapstone to disassemble instructions of samples.

Signed-off-by: Changbin Du <changbin.du@huawei.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: changbin.du@gmail.com
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240217074046.4100789-2-changbin.du@huawei.com


# f67f2fda 09-Nov-2023 Namhyung Kim <namhyung@kernel.org>

perf build: Add feature check for dwarf_getcfi()

The dwarf_getcfi() is available on libdw 0.142+. Instead of just
checking the version number, it'd be nice to have a config item to check
the feature at build time.

Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231110000012.3538610-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 9e03608e 04-Apr-2023 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add a feature test for scandirat(), that is not implemented so far in musl and uclibc

We use it just when listing tracepoint events, and for root, so just
emit a warning about it to get users to ask the library maintainers to
implement it, as suggested in this systemd ticket:

https://github.com/systemd/casync/issues/129

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZCwv4z5Dh%2FdHUMG6@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 4c72e2b3 10-Mar-2023 Ian Rogers <irogers@google.com>

tools build: Add feature test for abi::__cxa_demangle

cxxabi.h is part of libsdtc++ and LLVM's libcxx, providing
abi::__cxa_demangle a portable C++ demangler. Add a feature test to
detect that the function is available.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Tom Rix <trix@redhat.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230311065753.3012826-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# f1bdebbb 19-Oct-2022 Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Fix build with libbpf 0.7.0 by checking if bpf_program__set_insns() is available

During the transition to libbpf 1.0 some functions that perf used were
deprecated and finally removed from libbpf, so bpf_program__set_insns()
was introduced for perf to continue to use its bpf loader.

But when build with LIBBPF_DYNAMIC=1 we now need to check if that
function is available so that perf can build with older libbpf versions,
even if the end result is emitting a warning to the user that the use
of the perf BPF loader requires a newer libbpf, since bpf_program__set_insns()
touches libbpf objects internal state.

This affects only 'perf trace' when using bpf C code or pre-compiled
bytecode as an event.

Noticed on RHEL9, that has libbpf 0.7.0, where bpf_program__set_insns()
isn't available.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 74ef1cc9 18-Aug-2022 Roberto Sassu <roberto.sassu@huawei.com>

tools build: Display logical OR of a feature flavors

Sometimes, features are simply different flavors of another feature, to
properly detect the exact dependencies needed by different Linux
distributions.

For example, libbfd has three flavors: libbfd if the distro does not
require any additional dependency; libbfd-liberty if it requires libiberty;
libbfd-liberty-z if it requires libiberty and libz.

It might not be clear to the user whether a feature has been successfully
detected or not, given that some of its flavors will be set to OFF, others
to ON.

Instead, display only the feature main flavor if not in verbose mode
(VF != 1), and set it to ON if at least one of its flavors has been
successfully detected (logical OR), OFF otherwise. Omit the other flavors.

Accomplish that by declaring a FEATURE_GROUP_MEMBERS-<feature main flavor>
variable, with the list of the other flavors as variable value. For now, do
it just for libbfd.

In verbose mode, of if no group is defined for a feature, show the feature
detection result as before.

Committer testing:

Collecting the output from:

$ make -C tools/bpf/bpftool/ clean
$ make -C tools/bpf/bpftool/ |& grep "Auto-detecting system features" -A10

$ diff -u before after
--- before 2022-08-18 10:06:40.422086966 -0300
+++ after 2022-08-18 10:07:59.202138282 -0300
@@ -1,6 +1,4 @@
Auto-detecting system features:
... libbfd: [ on ]
-... libbfd-liberty: [ on ]
-... libbfd-liberty-z: [ on ]
... libcap: [ on ]
... clang-bpf-co-re: [ on ]
$

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20220818120957.319995-3-roberto.sassu@huaweicloud.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 74da7697 18-Aug-2022 Roberto Sassu <roberto.sassu@huawei.com>

tools build: Increment room for feature name in feature detection output

Since now there are features with a long name, increase the room for them,
so that fields are correctly aligned.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20220818120957.319995-2-roberto.sassu@huaweicloud.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 709533e5 18-Aug-2022 Roberto Sassu <roberto.sassu@huawei.com>

tools build: Fix feature detection output due to eval expansion

As the first eval expansion is used only to generate Makefile statements,
messages should not be displayed at this stage, as for example conditional
expressions are not evaluated.

It can be seen for example in the output of feature detection for bpftool,
where the number of detected features does not change, despite turning on
the verbose mode (VF = 1) and there are additional features to display.

Fix this issue by escaping the $ before $(info) statements, to ensure that
messages are printed only when the function containing them is actually
executed, and not when it is expanded.

In addition, move the $(info) statement out of feature_print_status, due to
the fact that is called both inside and outside an eval context, and place
it to the caller so that the $ can be escaped when necessary. For symmetry,
move the $(info) statement also out of feature_print_text, and place it to
the caller.

Force the TMP variable evaluation in verbose mode, to display the features
in FEATURE_TESTS that are not in FEATURE_DISPLAY.

Reorder perf feature detection messages (first non-verbose, then verbose
ones) by moving the call to feature_display_entries earlier, before the VF
environment variable check.

Also, remove the newline from that function, as perf might display
additional messages. Move the newline to perf Makefile, and display another
one if displaying the detection result is not deferred as in the case of
bpftool.

Committer testing:

Collecting the output from:

$ make VF=1 -C tools/bpf/bpftool/ |& grep "Auto-detecting system features" -A20

$ diff -u before after
--- before 2022-08-18 09:59:55.460529231 -0300
+++ after 2022-08-18 10:01:11.182517282 -0300
@@ -4,3 +4,5 @@
... libbfd-liberty-z: [ on ]
... libcap: [ on ]
... clang-bpf-co-re: [ on ]
+... disassembler-four-args: [ on ]
+... disassembler-init-styled: [ OFF ]
$

Fixes: 0afc5cad387db560 ("perf build: Separate feature make support into config/Makefile.feature")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: bpf@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20220818120957.319995-1-roberto.sassu@huaweicloud.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 516ddaad 31-Jul-2022 Andres Freund <andres@anarazel.de>

tools build: Don't display disassembler-four-args feature test

The feature check does not seem important enough to display. Suggested by
Jiri Olsa.

Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <benh@debian.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-3-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# cfd59ca9 31-Jul-2022 Andres Freund <andres@anarazel.de>

tools build: Add feature test for init_disassemble_info API changes

binutils changed the signature of init_disassemble_info(), which now causes
compilation failures for tools/{perf,bpf}, e.g. on debian unstable.

Relevant binutils commit:

https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07

This commit adds a feature test to detect the new signature. Subsequent
commits will use it to fix the build failures.

Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <benh@debian.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-2-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# df76e003 26-May-2022 Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Stop using __weak bpf_map_create() to handle older libbpf versions

By adding a feature test for bpf_map_create() and providing a fallback if
it isn't present in older versions of libbpf.

This also fixes the build with torvalds/master at this point:

$ git log --oneline -5 torvalds/master
babf0bb978e3c9fc (torvalds/master) Merge tag 'xfs-5.19-for-linus' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
e375780b631a5fc2 Merge tag 'fsnotify_for_v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
8b728edc5be16179 Merge tag 'fs_for_v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
3f306ea2e18568f6 Merge tag 'dma-mapping-5.19-2022-05-25' of git://git.infradead.org/users/hch/dma-mapping
fbe86daca0ba878b Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
$

Coping with:

$ git log --oneline -2 d16495a982324f75
d16495a982324f75 libbpf: remove bpf_create_map*() APIs
e2371b1632b1c61c libbpf: start 1.0 development cycle
$

As the __weak function fails to build as it calls the now removed
bpf_create_map() API.

Testing:

$ rpm -q libbpf-devel
libbpf-devel-0.4.0-2.fc35.x86_64
$
$ make -C tools/perf BUILD_BPF_SKEL=1 LIBBPF_DYNAMIC=1 O=/tmp/build/perf install-bin
$ cat /tmp/build/perf/feature/test-libbpf-bpf_map_create.make.output
test-libbpf-bpf_map_create.c: In function ‘main’:
test-libbpf-bpf_map_create.c:6:16: error: implicit declaration of function ‘bpf_map_create’; did you mean ‘bpf_map_freeze’? [-Werror=implicit-function-declaration]
6 | return bpf_map_create(0 /* map_type */, NULL /* map_name */, 0, /* key_size */,
| ^~~~~~~~~~~~~~
| bpf_map_freeze
test-libbpf-bpf_map_create.c:6:87: error: expected expression before ‘,’ token
6 | return bpf_map_create(0 /* map_type */, NULL /* map_name */, 0, /* key_size */,
| ^
cc1: all warnings being treated as errors
$
$ objdump -dS /tmp/build/perf/perf | grep '<bpf_map_create>:' -A20
000000000058b290 <bpf_map_create>:
{
58b290: 55 push %rbp
58b291: 48 89 e5 mov %rsp,%rbp
58b294: 48 83 ec 10 sub $0x10,%rsp
58b298: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
58b29f: 00 00
58b2a1: 48 89 45 f8 mov %rax,-0x8(%rbp)
58b2a5: 31 c0 xor %eax,%eax
return bpf_create_map(map_type, key_size, value_size, max_entries, 0);
58b2a7: 48 8b 45 f8 mov -0x8(%rbp),%rax
58b2ab: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax
58b2b2: 00 00
58b2b4: 75 10 jne 58b2c6 <bpf_map_create+0x36>
}
58b2b6: c9 leave
58b2b7: 89 d6 mov %edx,%esi
58b2b9: 89 ca mov %ecx,%edx
58b2bb: 44 89 c1 mov %r8d,%ecx
return bpf_create_map(map_type, key_size, value_size, max_entries, 0);
58b2be: 45 31 c0 xor %r8d,%r8d
$

Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Song Liu <songliubraving@fb.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/Yo+XvQNKL4K5khl2@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 739c9180 24-May-2022 Jiri Olsa <jolsa@kernel.org>

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>


# 8916d725 24-May-2022 Jiri Olsa <jolsa@kernel.org>

perf build: Stop using __weak bpf_object__next_program() to handle older libbpf versions

By adding a feature test for bpf_object__next_program() 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_program.make.output
test-libbpf-bpf_object__next_program.c: In function ‘main’:
test-libbpf-bpf_object__next_program.c:6:9: error: implicit declaration of function ‘bpf_object__next_program’; did you mean ‘bpf_object__unpin_programs’? [-Werror=implicit-function-declaration]
6 | bpf_object__next_program(NULL /* obj */, NULL /* prev */);
| ^~~~~~~~~~~~~~~~~~~~~~~~
| bpf_object__unpin_programs
cc1: all warnings being treated as errors
$
$ objdump -dS /tmp/build/perf/perf | grep '<bpf_object__next_program>:' -A20
00000000005b2dc0 <bpf_object__next_program>:
{
5b2dc0: 55 push %rbp
5b2dc1: 48 89 e5 mov %rsp,%rbp
5b2dc4: 48 83 ec 10 sub $0x10,%rsp
5b2dc8: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5b2dcf: 00 00
5b2dd1: 48 89 45 f8 mov %rax,-0x8(%rbp)
5b2dd5: 31 c0 xor %eax,%eax
return bpf_program__next(prev, obj);
5b2dd7: 48 8b 45 f8 mov -0x8(%rbp),%rax
5b2ddb: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax
5b2de2: 00 00
5b2de4: 75 0f jne 5b2df5 <bpf_object__next_program+0x35>
}
5b2de6: c9 leave
5b2de7: 49 89 f8 mov %rdi,%r8
5b2dea: 48 89 f7 mov %rsi,%rdi
return bpf_program__next(prev, obj);
5b2ded: 4c 89 c6 mov %r8,%rsi
5b2df0: e9 3b b4 e5 ff jmp 40e230 <bpf_program__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>


# 5c83eff3 24-May-2022 Jiri Olsa <jolsa@kernel.org>

perf build: Stop using __weak bpf_prog_load() to handle older libbpf versions

By adding a feature test for bpf_prog_load() 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_prog_load.make.output
test-libbpf-bpf_prog_load.c: In function ‘main’:
test-libbpf-bpf_prog_load.c:6:16: error: implicit declaration of function ‘bpf_prog_load’ [-Werror=implicit-function-declaration]
6 | return bpf_prog_load(0 /* prog_type */, NULL /* prog_name */,
| ^~~~~~~~~~~~~
cc1: all warnings being treated as errors
$

$ objdump -dS /tmp/build/perf/perf | grep '<bpf_prog_load>:' -A20
00000000005b2d70 <bpf_prog_load>:
{
5b2d70: 55 push %rbp
5b2d71: 48 89 ce mov %rcx,%rsi
5b2d74: 4c 89 c8 mov %r9,%rax
5b2d77: 49 89 d2 mov %rdx,%r10
5b2d7a: 4c 89 c2 mov %r8,%rdx
5b2d7d: 48 89 e5 mov %rsp,%rbp
5b2d80: 48 83 ec 18 sub $0x18,%rsp
5b2d84: 64 48 8b 0c 25 28 00 mov %fs:0x28,%rcx
5b2d8b: 00 00
5b2d8d: 48 89 4d f8 mov %rcx,-0x8(%rbp)
5b2d91: 31 c9 xor %ecx,%ecx
return bpf_load_program(prog_type, insns, insn_cnt, license,
5b2d93: 41 8b 49 5c mov 0x5c(%r9),%ecx
5b2d97: 51 push %rcx
5b2d98: 4d 8b 49 60 mov 0x60(%r9),%r9
5b2d9c: 4c 89 d1 mov %r10,%rcx
5b2d9f: 44 8b 40 1c mov 0x1c(%rax),%r8d
5b2da3: e8 f8 aa e5 ff call 40d8a0 <bpf_load_program@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>


# 0ae065a5d 19-May-2022 Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Fix check for btf__load_from_kernel_by_id() in libbpf

Avi Kivity reported a problem where the __weak
btf__load_from_kernel_by_id() in tools/perf/util/bpf-event.c was being
used and it called btf__get_from_id() in tools/lib/bpf/btf.c that in
turn called back to btf__load_from_kernel_by_id(), resulting in an
endless loop.

Fix this by adding a feature test to check if
btf__load_from_kernel_by_id() is available when building perf with
LIBBPF_DYNAMIC=1, and if not then provide the fallback to the old
btf__get_from_id(), that doesn't call back to btf__load_from_kernel_by_id()
since at that time it didn't exist at all.

Tested on Fedora 35 where we have libbpf-devel 0.4.0 with LIBBPF_DYNAMIC
where we don't have btf__load_from_kernel_by_id() and thus its feature
test fail, not defining HAVE_LIBBPF_BTF__LOAD_FROM_KERNEL_BY_ID:

$ cat /tmp/build/perf-urgent/feature/test-libbpf-btf__load_from_kernel_by_id.make.output
test-libbpf-btf__load_from_kernel_by_id.c: In function ‘main’:
test-libbpf-btf__load_from_kernel_by_id.c:6:16: error: implicit declaration of function ‘btf__load_from_kernel_by_id’ [-Werror=implicit-function-declaration]
6 | return btf__load_from_kernel_by_id(20151128, NULL);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
$

$ nm /tmp/build/perf-urgent/perf | grep btf__load_from_kernel_by_id
00000000005ba180 T btf__load_from_kernel_by_id
$

$ objdump --disassemble=btf__load_from_kernel_by_id -S /tmp/build/perf-urgent/perf

/tmp/build/perf-urgent/perf: file format elf64-x86-64
<SNIP>
00000000005ba180 <btf__load_from_kernel_by_id>:
#include "record.h"
#include "util/synthetic-events.h"

#ifndef HAVE_LIBBPF_BTF__LOAD_FROM_KERNEL_BY_ID
struct btf *btf__load_from_kernel_by_id(__u32 id)
{
5ba180: 55 push %rbp
5ba181: 48 89 e5 mov %rsp,%rbp
5ba184: 48 83 ec 10 sub $0x10,%rsp
5ba188: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
5ba18f: 00 00
5ba191: 48 89 45 f8 mov %rax,-0x8(%rbp)
5ba195: 31 c0 xor %eax,%eax
struct btf *btf;
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
int err = btf__get_from_id(id, &btf);
5ba197: 48 8d 75 f0 lea -0x10(%rbp),%rsi
5ba19b: e8 a0 57 e5 ff call 40f940 <btf__get_from_id@plt>
5ba1a0: 89 c2 mov %eax,%edx
#pragma GCC diagnostic pop

return err ? ERR_PTR(err) : btf;
5ba1a2: 48 98 cltq
5ba1a4: 85 d2 test %edx,%edx
5ba1a6: 48 0f 44 45 f0 cmove -0x10(%rbp),%rax
}
<SNIP>

Fixes: 218e7b775d368f38 ("perf bpf: Provide a weak btf__load_from_kernel_by_id() for older libbpf versions")
Reported-by: Avi Kivity <avi@scylladb.com>
Link: https://lore.kernel.org/linux-perf-users/f0add43b-3de5-20c5-22c4-70aff4af959f@scylladb.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/linux-perf-users/YobjjFOblY4Xvwo7@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 3d1d57de 30-Nov-2021 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Remove needless libpython-version feature check that breaks test-all fast path

Since 66dfdff03d196e51 ("perf tools: Add Python 3 support") we don't use
the tools/build/feature/test-libpython-version.c version in any Makefile
feature check:

$ find tools/ -type f | xargs grep feature-libpython-version
$

The only place where this was used was removed in 66dfdff03d196e51:

- ifneq ($(feature-libpython-version), 1)
- $(warning Python 3 is not yet supported; please set)
- $(warning PYTHON and/or PYTHON_CONFIG appropriately.)
- $(warning If you also have Python 2 installed, then)
- $(warning try something like:)
- $(warning $(and ,))
- $(warning $(and ,) make PYTHON=python2)
- $(warning $(and ,))
- $(warning Otherwise, disable Python support entirely:)
- $(warning $(and ,))
- $(warning $(and ,) make NO_LIBPYTHON=1)
- $(warning $(and ,))
- $(error $(and ,))
- else
- LDFLAGS += $(PYTHON_EMBED_LDFLAGS)
- EXTLIBS += $(PYTHON_EMBED_LIBADD)
- LANG_BINDINGS += $(obj-perf)python/perf.so
- $(call detected,CONFIG_LIBPYTHON)
- endif

And nowadays we either build with PYTHON=python3 or just install the
python3 devel packages and perf will build against it.

But the leftover feature-libpython-version check made the fast path
feature detection to break in all cases except when python2 devel files
were installed:

$ rpm -qa | grep python.*devel
python3-devel-3.9.7-1.fc34.x86_64
$ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ;
$ make -C tools/perf O=/tmp/build/perf install-bin
make: Entering directory '/var/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j32' parallel build
HOSTCC /tmp/build/perf/fixdep.o
<SNIP>
$ cat /tmp/build/perf/feature/test-all.make.output
In file included from test-all.c:18:
test-libpython-version.c:5:10: error: #error
5 | #error
| ^~~~~
$ ldd ~/bin/perf | grep python
libpython3.9.so.1.0 => /lib64/libpython3.9.so.1.0 (0x00007fda6dbcf000)
$

As python3 is the norm these days, fix this by just removing the unused
feature-libpython-version feature check, making the test-all fast path
to work with the common case.

With this:

$ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ;
$ make -C tools/perf O=/tmp/build/perf install-bin |& head
make: Entering directory '/var/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j32' parallel build
HOSTCC /tmp/build/perf/fixdep.o
HOSTLD /tmp/build/perf/fixdep-in.o
LINK /tmp/build/perf/fixdep

Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
$ ldd ~/bin/perf | grep python
libpython3.9.so.1.0 => /lib64/libpython3.9.so.1.0 (0x00007f58800b0000)
$ cat /tmp/build/perf/feature/test-all.make.output
$

Reviewed-by: James Clark <james.clark@arm.com>
Fixes: 66dfdff03d196e51 ("perf tools: Add Python 3 support")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jaroslav Škarvada <jskarvad@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/YaYmeeC6CS2b8OSz@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# b758a61b 22-Sep-2021 Ian Rogers <irogers@google.com>

perf tools: Enable libtracefs dynamic linking

Currently libtracefs isn't used by perf, but there are potential
improvements by using it as identified Steven Rostedt's e-mail:
https://lore.kernel.org/lkml/20210610154759.1ef958f0@oasis.local.home/

This change is modelled on the dynamic libtraceevent patch by Michael
Petlan:

https://lore.kernel.org/linux-perf-users/20210428092023.4009-1-mpetlan@redhat.com/

v3. Adds file missed in v1 and v2 spotted by Jiri Olsa.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/lkml/20210923001024.550263-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 60fa754b 09-Aug-2021 Leo Yan <leo.yan@linaro.org>

tools: Remove feature-sync-compare-and-swap feature detection

Since the __sync functions have been removed from perf, it's needless
for perf tool to test the feature sync-compare-and-swap.

The feature test is not used by any other components, remove it.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20210809111407.596077-10-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 19177bc3 26-Apr-2021 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Allow deferring printing the results of feature detection

By setting FEATURE_DISPLAY_DEFERRED=1 a tool may ask for the printout
of the detected features in tools/build/Makefile.feature to be done
later adter extra feature checks are done that are tool specific.

The perf tool will do it via its tools/perf/Makefile.config, as it
performs such extra feature checks.

Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 56d32d4c 28-Apr-2021 Michael Petlan <mpetlan@redhat.com>

perf tools: Enable libtraceevent dynamic linking

Currently we support only static linking with kernel's libtraceevent
(tools/lib/traceevent). This patch adds libtraceevent package detection
and support to link perf with it dynamically.

The libtraceevent package status is displayed with:
$ make VF=1 LIBTRACEEVENT_DYNAMIC=1
...
... libtraceevent: [ on ]

Default behavior remains the same (static linking).

Committer testing:

$ make LIBTRACEEVENT_DYNAMIC=1 VF=1 O=/tmp/build/perf -C tools/perf install-bin |& grep traceevent
Makefile.config:1090: *** Error: No libtraceevent devel library found, please install libtraceevent-devel. Stop.
$

Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
LPU-Reference: 20210428092023.4009-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# fbcdaa19 29-Dec-2020 Song Liu <songliubraving@fb.com>

perf build: Support build BPF skeletons with perf

BPF programs are useful in perf to profile BPF programs.

BPF skeleton is by far the easiest way to write BPF tools. Enable
building BPF skeletons in util/bpf_skel. A dummy bpf skeleton is added.
More bpf skeletons will be added for different use cases.

Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Link: http://lore.kernel.org/lkml/20201229214214.3413833-3-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 4751bddd 04-Sep-2020 Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Make GTK2 support opt-in

This is bitrotting, nobody is stepping up to work on it, and since we
treat warnings as errors, feature detection is failing in its main,
faster test (tools/build/feature/test-all.c) because of the GTK+2
infobar check.

So make this opt-in, at some point ditch this if nobody volunteers to
take care of this.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e71e19a9 03-Sep-2020 Arnaldo Carvalho de Melo <acme@redhat.com>

tools features: Add feature test to check if libbfd has buildid support

Which is needed by the PE executable support, for instance.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jacek Caban <jacek@codeweavers.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Remi Bernon <rbernon@codeweavers.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 22dd1ac9 18-Aug-2020 Andrii Nakryiko <andriin@fb.com>

tools: Remove feature-libelf-mmap feature detection

It's trivial to handle missing ELF_C_MMAP_READ support in libelf the way that
objtool has solved it in
("774bec3fddcc objtool: Add fallback from ELF_C_READ_MMAP to ELF_C_READ").

So instead of having an entire feature detector for that, just do what objtool
does for perf and libbpf. And keep their Makefiles a bit simpler.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200819013607.3607269-5-andriin@fb.com


# c7a14fdc 13-Aug-2020 Frank Ch. Eigler <fche@redhat.com>

perf build-ids: Fall back to debuginfod query if debuginfo not found

During a perf-record, use the -ldebuginfod API to query a debuginfod
server, should the debug data not be found in the usual system
locations. If successful, the usual $HOME/.debug dir is populated.

Tested with:

$ find .
.
./ctags-debuginfo-5.8-26.fc31.x86_64.rpm
./usr
./usr/lib
./usr/lib/debug
./usr/lib/debug/.build-id
./usr/lib/debug/.build-id/ca
./usr/lib/debug/.build-id/ca/46f6ae6a0cee57d85abc1d461c49074248908d
./usr/lib/debug/.build-id/ca/46f6ae6a0cee57d85abc1d461c49074248908d.debug
./usr/lib/debug/usr
./usr/lib/debug/usr/bin
./usr/lib/debug/usr/bin/ctags-5.8-26.fc31.x86_64.debug

$ debuginfod -F .
...

$ rm -rf ~/.debug/ ; mkdir ~/.debug

$ perf record make tags
BUILD: Doing 'make -j8' parallel build
GEN tags
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.107 MB perf.data (1483 samples) ]

$ find ~/.debug | grep ctags
/home/jolsa/.debug/usr/bin/ctags
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/elf
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/probes

$ rm -rf ~/.debug/ ; mkdir ~/.debug

$ DEBUGINFOD_URLS=http://localhost:8002 perf record make tags
BUILD: Doing 'make -j8' parallel build
GEN tags
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.108 MB perf.data (1531 samples) ]

$ find ~/.debug | grep ctag
/home/jolsa/.debug/usr/bin/ctags
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/debug
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/elf
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/probes

Note the 'debug' file is created in the last run.

Note that currently the debuginfo data are downloaded only on record path,
we still need add this support to perf build-id/report.. and test ;-)

Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Frank Ch. Eigler <fche@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# fa5c8931 12-Aug-2020 Daniel Díaz <daniel.diaz@linaro.org>

tools build feature: Quote CC and CXX for their arguments

When using a cross-compilation environment, such as OpenEmbedded,
the CC an CXX variables are set to something more than just a
command: there are arguments (such as --sysroot) that need to be
passed on to the compiler so that the right set of headers and
libraries are used.

For the particular case that our systems detected, CC is set to
the following:

export CC="aarch64-linaro-linux-gcc --sysroot=/oe/build/tmp/work/machine/perf/1.0-r9/recipe-sysroot"

Without quotes, detection is as follows:

Auto-detecting system features:
... dwarf: [ OFF ]
... dwarf_getlocations: [ OFF ]
... glibc: [ OFF ]
... gtk2: [ OFF ]
... libbfd: [ OFF ]
... libcap: [ OFF ]
... libelf: [ OFF ]
... libnuma: [ OFF ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ OFF ]
... libpython: [ OFF ]
... libcrypto: [ OFF ]
... libunwind: [ OFF ]
... libdw-dwarf-unwind: [ OFF ]
... zlib: [ OFF ]
... lzma: [ OFF ]
... get_cpuid: [ OFF ]
... bpf: [ OFF ]
... libaio: [ OFF ]
... libzstd: [ OFF ]
... disassembler-four-args: [ OFF ]

Makefile.config:414: *** No gnu/libc-version.h found, please install glibc-dev[el]. Stop.
Makefile.perf:230: recipe for target 'sub-make' failed
make[1]: *** [sub-make] Error 2
Makefile:69: recipe for target 'all' failed
make: *** [all] Error 2

With CC and CXX quoted, some of those features are now detected.

Fixes: e3232c2f39ac ("tools build feature: Use CC and CXX from parent")
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Reviewed-by: Thomas Hebb <tommyhebb@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Link: http://lore.kernel.org/lkml/20200812221518.2869003-1-daniel.diaz@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e3232c2f 26-Jul-2020 Thomas Hebb <tommyhebb@gmail.com>

tools build feature: Use CC and CXX from parent

commit c8c188679ccf ("tools build: Use the same CC for feature detection
and actual build") changed these assignments from unconditional (:=) to
conditional (?=) so that they wouldn't clobber values from the
environment. However, conditional assignment does not work properly for
variables that Make implicitly sets, among which are CC and CXX. To
quote tools/scripts/Makefile.include, which handles this properly:

# Makefiles suck: This macro sets a default value of $(2) for the
# variable named by $(1), unless the variable has been set by
# environment or command line. This is necessary for CC and AR
# because make sets default values, so the simpler ?= approach
# won't work as expected.

In other words, the conditional assignments will not run even if the
variables are not overridden in the environment; Make will set CC to
"cc" and CXX to "g++" when it starts[1], meaning the variables are not
empty by the time the conditional assignments are evaluated. This breaks
cross-compilation when CROSS_COMPILE is set but CC isn't, since "cc"
gets used for feature detection instead of the cross compiler (and
likewise for CXX).

To fix the issue, just pass down the values of CC and CXX computed by
the parent Makefile, which gets included by the Makefile that actually
builds whatever we're detecting features for and so is guaranteed to
have good values. This is a better solution anyway, since it means we
aren't trying to replicate the logic of the parent build system and so
don't risk it getting out of sync.

Leave PKG_CONFIG alone, since 1) there's no common logic to compute it
in Makefile.include, and 2) it's not an implicit variable, so
conditional assignment works properly.

[1] https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html

Fixes: c8c188679ccf ("tools build: Use the same CC for feature detection and actual build")
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: thomas hebb <tommyhebb@gmail.com>
Link: http://lore.kernel.org/lkml/0a6e69d1736b0fa231a648f50b0cce5d8a6734ef.1595822871.git.tommyhebb@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# a88f70de 29-May-2020 Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Remove libaudit from the default feature checks

Ingo reported that the libaudit was always appearing as OFF:

Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ on ]
... libaudit: [ OFF ]

And everything seemed to work, i.e. we were checking for a feature that
we don't use, causing confusion for people building perf, so work to
remove that nuisance while making sure that it works when an arch
doesn't provide the alternative method to generate the syscall id/name
conversion tables.

Longer explanation of the new modus operandi:

$ make -C tools/perf O=/tmp/build/perf NO_SYSCALL_TABLE=1
<SNIP>
Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ on ]
... libbfd: [ on ]
... libcap: [ on ]
... libelf: [ on ]
... libnuma: [ on ]
... numa_num_possible_cpus: [ on ]
... libperl: [ on ]
... libpython: [ on ]
... libcrypto: [ on ]
... libunwind: [ on ]
... libdw-dwarf-unwind: [ on ]
... zlib: [ on ]
... lzma: [ on ]
... get_cpuid: [ on ]
... bpf: [ on ]
... libaio: [ on ]
... libzstd: [ on ]
... disassembler-four-args: [ on ]

Makefile.config:665: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev
GEN /tmp/build/perf/common-cmds.h
MKDIR /tmp/build/perf/fd/
MKDIR /tmp/build/perf/fs/
<SNIP>
$

The libaudit test is forced and it fails when audit-libs-devel isn't available:

$ cat /tmp/build/perf/feature/test-libaudit.make.output
test-libaudit.c:2:10: fatal error: libaudit.h: No such file or directory
2 | #include <libaudit.h>
| ^~~~~~~~~~~~
compilation terminated.
$

If we install audit-libs-devel and rebuild it continues not to be shown as OFF
in the main auto-detection summary, but again gets tested and this time:

$ rpm -q audit-libs-devel
audit-libs-devel-3.0-0.15.20191104git1c2f876.fc31.x86_64
$

The make output for the feature detection comes clean:

$ cat /tmp/build/perf/feature/test-libaudit.make.output

And the feature detection binary is successfully built and is dynamicly linked
with libaudit:

$ ldd /tmp/build/perf/feature/test-libaudit.bin | grep audit
libaudit.so.1 => /lib64/libaudit.so.1 (0x00007f5bf5177000)
$

As well as the resulting perf binary:

$ ldd /tmp/build/perf/perf | grep audit
libaudit.so.1 => /lib64/libaudit.so.1 (0x00007fad511c7000)
$

And 'perf trace' works using the libaudit method:

$ sudo /tmp/build/perf/perf trace -e nanosleep sleep 1
0.000 (1000.067 ms): sleep/281872 nanosleep(rqtp: 0x7ffedbbe69d0) = 0
$

If we leave audit-libs-devel installed but don't disable the use of the best
method, the one using SYSCALL_TABLE, the default for architectures that provide
the script to build the syscall id/name mapping using the .tbl files copied
from the kernel sources, we get:

$ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf
$ make -C tools/perf O=/tmp/build/perf
Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ on ]
... libbfd: [ on ]
... libcap: [ on ]
... libelf: [ on ]
... libnuma: [ on ]
... numa_num_possible_cpus: [ on ]
... libperl: [ on ]
... libpython: [ on ]
... libcrypto: [ on ]
... libunwind: [ on ]
... libdw-dwarf-unwind: [ on ]
... zlib: [ on ]
... lzma: [ on ]
... get_cpuid: [ on ]
... bpf: [ on ]
... libaio: [ on ]
... libzstd: [ on ]
... disassembler-four-args: [ on ]

GEN /tmp/build/perf/common-cmds.h
<SNIP>
$

Again, no mention of libaudit being on or OFF and:

$ cat /tmp/build/perf/feature/test-libaudit.make.output
cat: /tmp/build/perf/feature/test-libaudit.make.output: No such file or directory
$

We didn't even bother checking for its availability, slightly speeding up the
build process and:

$ ldd /tmp/build/perf/perf | grep libaudit
$

We don't link with it, also:

$ sudo /tmp/build/perf/perf trace -e nanosleep sleep 1
0.000 (1000.053 ms): sleep/299125 nanosleep(rqtp: 0x7ffc24611b50) = 0
$

And globs become available:

$ sudo /tmp/build/perf/perf trace -e *sleep sleep 1
0.000 (1000.072 ms): sleep/299136 nanosleep(rqtp: 0x7ffe7a3c4ff0) = 0
$

Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 5ef86146 29-Apr-2020 Stephane Eranian <eranian@google.com>

tools feature: Add support for detecting libpfm4

libpfm4 provides an alternate command line encoding of perf events.

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiwei Sun <jiwei.sun@windriver.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: yuzhoujian <yuzhoujian@didichuxing.com>
Link: http://lore.kernel.org/lkml/20200429231443.207201-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 49f550ea 01-Apr-2020 Namhyung Kim <namhyung@kernel.org>

perf tools: Add file-handle feature test

The file handle (FHANDLE) support is configurable so some systems might not
have it. So add a config feature item to check it on build time so that we
don't add the cgroup tracking feature based on that.

Committer notes:

Had to make the test use the same construct as its later use in
synthetic-events.c, in the next patch in this series. i.e. make it be:

struct {
struct file_handle fh;
uint64_t cgroup_id;
} handle;

To cope with:

CC /tmp/build/perf/util/cloexec.o
util/synthetic-events.c:428:22: error: field 'fh' with CC /tmp/build/perf/util/call-path.o
variable sized type 'struct file_handle' not at the end of a struct or class is a GNU
extension [-Werror,-Wgnu-variable-sized-type-not-at-end]
struct file_handle fh;
^
1 error generated.

Deal with this at some point, i.e. investigate if the right thing is to
remove that -Wgnu-variable-sized-type-not-at-end from our CFLAGS, for
now do the test the same way as it is used looks more sensible.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200402015249.3800462-1-namhyung@kernel.org
[ split from a larger patch, removed blank line at EOF ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 7b65e203 26-Nov-2019 Jiri Olsa <jolsa@kernel.org>

perf tools: Allow to link with libbpf dynamicaly

Currently we support only static linking with kernel's libbpf
(tools/lib/bpf). This patch adds libbpf package detection and support to
link perf with it dynamically.

The libbpf package status is displayed with:

$ make VF=1
Auto-detecting system features:
...
... libbpf: [ on ]

It's not checked by default, because it's quite new. Once it's on most
distros we can switch it on.

For the same reason it's not added to the test-all check.

Perf does not need advanced version of libbpf, so we can check just for
the base bpf_object__open function.

Adding new compile variable to detect libbpf package and link bpf
dynamically:

$ make LIBBPF_DYNAMIC=1
...
LINK perf
$ ldd perf | grep bpf
libbpf.so.0 => /lib64/libbpf.so.0 (0x00007f46818bc000)

If libbpf is not installed, build stops with:

Makefile.config:486: *** Error: No libbpf devel library found,\
please install libbpf-devel. Stop.

Committer testing:

$ make LIBBPF_DYNAMIC=1 -C tools/perf O=/tmp/build/perf
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build
Makefile.config:493: *** Error: No libbpf devel library found, please install libbpf-devel. Stop.
make[1]: *** [Makefile.perf:225: sub-make] Error 2
make: *** [Makefile:70: all] Error 2
make: Leaving directory '/home/acme/git/perf/tools/perf'
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191126121253.28253-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 74d5f3d0 07-Aug-2019 Igor Lubashev <ilubashe@akamai.com>

tools build: Add capability-related feature detection

Add utilities to help checking capabilities of the running procss. Make
perf link with libcap, if it is available. If no libcap-dev[el], assume
no capabilities.

Committer testing:

$ make O=/tmp/build/perf -C tools/perf install-bin
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build

Auto-detecting system features:
<SNIP>
... libbfd: [ on ]
... libcap: [ OFF ]
... libelf: [ on ]
<SNIP>
Makefile.config:833: No libcap found, disables capability support, please install libcap-devel/libcap-dev
<SNIP>
$ grep libcap /tmp/build/perf/FEATURE-DUMP
feature-libcap=0
$ cat /tmp/build/perf/feature/test-libcap.make.output
test-libcap.c:2:10: fatal error: sys/capability.h: No such file or directory
2 | #include <sys/capability.h>
| ^~~~~~~~~~~~~~~~~~
compilation terminated.
$

Now install libcap-devel and try again:

$ make O=/tmp/build/perf -C tools/perf install-bin
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build
Warning: Kernel ABI header at 'tools/include/linux/bits.h' differs from latest version at 'include/linux/bits.h'
diff -u tools/include/linux/bits.h include/linux/bits.h
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h

Auto-detecting system features:
<SNIP>
... libbfd: [ on ]
... libcap: [ on ]
... libelf: [ on ]
<SNIP>>
CC /tmp/build/perf/jvmti/libjvmti.o
<SNIP>>
$ grep libcap /tmp/build/perf/FEATURE-DUMP
feature-libcap=1
$ cat /tmp/build/perf/feature/test-libcap.make.output
$ ldd /tmp/build/perf/feature/test-libcap.make.bin
ldd: /tmp/build/perf/feature/test-libcap.make.bin: No such file or directory
$ ldd /tmp/build/perf/feature/test-libcap.bin
linux-vdso.so.1 (0x00007ffc35bfe000)
libcap.so.2 => /lib64/libcap.so.2 (0x00007ff9c62ff000)
libc.so.6 => /lib64/libc.so.6 (0x00007ff9c6139000)
/lib64/ld-linux-x86-64.so.2 (0x00007ff9c6326000)
$

Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
[ split from a larger patch ]
Link: http://lkml.kernel.org/r/8a1e76cf5c7c9796d0d4d240fbaa85305298aafa.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 05c78468 12-Jun-2019 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Check if gettid() is available before providing helper

Laura reported that the perf build failed in fedora when we got a glibc
that provides gettid(), which I reproduced using fedora rawhide with the
glibc-devel-2.29.9000-26.fc31.x86_64 package.

Add a feature check to avoid providing a gettid() helper in such
systems.

On a fedora rawhide system with this patch applied we now get:

[root@7a5f55352234 perf]# grep gettid /tmp/build/perf/FEATURE-DUMP
feature-gettid=1
[root@7a5f55352234 perf]# cat /tmp/build/perf/feature/test-gettid.make.output
[root@7a5f55352234 perf]# ldd /tmp/build/perf/feature/test-gettid.bin
linux-vdso.so.1 (0x00007ffc6b1f6000)
libc.so.6 => /lib64/libc.so.6 (0x00007f04e0a74000)
/lib64/ld-linux-x86-64.so.2 (0x00007f04e0c47000)
[root@7a5f55352234 perf]# nm /tmp/build/perf/feature/test-gettid.bin | grep -w gettid
U gettid@@GLIBC_2.30
[root@7a5f55352234 perf]#

While on a fedora:29 system:

[acme@quaco perf]$ grep gettid /tmp/build/perf/FEATURE-DUMP
feature-gettid=0
[acme@quaco perf]$ cat /tmp/build/perf/feature/test-gettid.make.output
test-gettid.c: In function ‘main’:
test-gettid.c:8:9: error: implicit declaration of function ‘gettid’; did you mean ‘getgid’? [-Werror=implicit-function-declaration]
return gettid();
^~~~~~
getgid
cc1: all warnings being treated as errors
[acme@quaco perf]$

Reported-by: Laura Abbott <labbott@redhat.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/n/tip-yfy3ch53agmklwu9o7rlgf9c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# cbefd24f 18-Jun-2019 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add test to check if slang.h is in /usr/include/slang/

A few odd old distros (rhel5, 6, yeah, lots of those out in use, in many
cases we want to use upstream perf on it) have the slang header files in
/usr/include/slang/, so add a test that will be performed only when
test-all.c (the one with the most common sane settings) fails, either
because we're in one of these odd distros with slang/slang.h or because
something else failed (say libelf is not present).

So for the common case nothing changes, no additional test is performed.

Next step is to check in perf the result of these tests.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 1955c8cf5e26 ("perf tools: Don't hardcode host include path for libslang")
Link: https://lkml.kernel.org/n/tip-2sy7hbwkx68jr6n97qxgg0c6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 4541a8bb 12-Jun-2019 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Check if gettid() is available before providing helper

Laura reported that the perf build failed in fedora when we got a glibc
that provides gettid(), which I reproduced using fedora rawhide with the
glibc-devel-2.29.9000-26.fc31.x86_64 package.

Add a feature check to avoid providing a gettid() helper in such
systems.

On a fedora rawhide system with this patch applied we now get:

[root@7a5f55352234 perf]# grep gettid /tmp/build/perf/FEATURE-DUMP
feature-gettid=1
[root@7a5f55352234 perf]# cat /tmp/build/perf/feature/test-gettid.make.output
[root@7a5f55352234 perf]# ldd /tmp/build/perf/feature/test-gettid.bin
linux-vdso.so.1 (0x00007ffc6b1f6000)
libc.so.6 => /lib64/libc.so.6 (0x00007f04e0a74000)
/lib64/ld-linux-x86-64.so.2 (0x00007f04e0c47000)
[root@7a5f55352234 perf]# nm /tmp/build/perf/feature/test-gettid.bin | grep -w gettid
U gettid@@GLIBC_2.30
[root@7a5f55352234 perf]#

While on a fedora:29 system:

[acme@quaco perf]$ grep gettid /tmp/build/perf/FEATURE-DUMP
feature-gettid=0
[acme@quaco perf]$ cat /tmp/build/perf/feature/test-gettid.make.output
test-gettid.c: In function ‘main’:
test-gettid.c:8:9: error: implicit declaration of function ‘gettid’; did you mean ‘getgid’? [-Werror=implicit-function-declaration]
return gettid();
^~~~~~
getgid
cc1: all warnings being treated as errors
[acme@quaco perf]$

Reported-by: Laura Abbott <labbott@redhat.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/n/tip-yfy3ch53agmklwu9o7rlgf9c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# ec8f24b7 19-May-2019 Thomas Gleixner <tglx@linutronix.de>

treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 3b1c5d96 18-Mar-2019 Alexey Budankov <alexey.budankov@linux.intel.com>

tools build: Implement libzstd feature check, LIBZSTD_DIR and NO_LIBZSTD defines

Implement libzstd feature check, NO_LIBZSTD and LIBZSTD_DIR defines to
override Zstd library sources or disable the feature from the command
line:

$ make -C tools/perf LIBZSTD_DIR=/path/to/zstd/sources/ clean all
$ make -C tools/perf NO_LIBZSTD=1 clean all

Auto detection feature status is reported just before compilation
starts. If your system has some version of the zstd library
preinstalled then the build system finds and uses it during the build.

If you still prefer to compile with some other version of zstd library
you have capability to refer the compilation to that version using
LIBZSTD_DIR define.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/9b4cd8b0-10a3-1f1e-8d6b-5922a7ca216b@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 8a1b1718 11-Mar-2019 Song Liu <songliubraving@fb.com>

perf build: Check what binutils's 'disassembler()' signature to use

Commit 003ca0fd2286 ("Refactor disassembler selection") in the binutils
repo, which changed the disassembler() function signature, so we must
use the feature test introduced in fb982666e380 ("tools/bpftool: fix
bpftool build with bintutils >= 2.9") to deal with that.

Committer testing:

After adding the missing function call to test-all.c, and:

FEATURE_CHECK_LDFLAGS-disassembler-four-args = -bfd -lopcodes

And the fallbacks for cases where we need -liberty and sometimes -lz to
tools/perf/Makefile.config, we get:

$ make -C tools/perf O=/tmp/build/perf install-bin
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build

Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ on ]
... libaudit: [ on ]
... libbfd: [ on ]
... libelf: [ on ]
... libnuma: [ on ]
... numa_num_possible_cpus: [ on ]
... libperl: [ on ]
... libpython: [ on ]
... libslang: [ on ]
... libcrypto: [ on ]
... libunwind: [ on ]
... libdw-dwarf-unwind: [ on ]
... zlib: [ on ]
... lzma: [ on ]
... get_cpuid: [ on ]
... bpf: [ on ]
... libaio: [ on ]
... disassembler-four-args: [ on ]
CC /tmp/build/perf/jvmti/libjvmti.o
CC /tmp/build/perf/builtin-bench.o
<SNIP>
$
$

The feature detection test-all.bin gets successfully built and linked:

$ ls -la /tmp/build/perf/feature/test-all.bin
-rwxrwxr-x. 1 acme acme 2680352 Mar 19 11:07 /tmp/build/perf/feature/test-all.bin
$ nm /tmp/build/perf/feature/test-all.bin | grep -w disassembler
0000000000061f90 T disassembler
$

Time to move on to the patches that make use of this disassembler()
routine in binutils's libopcodes.

Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-13-songliubraving@fb.com
[ split from a larger patch, added missing FEATURE_CHECK_LDFLAGS-disassembler-four-args ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 5c4d7c82 12-Feb-2019 Arnaldo Carvalho de Melo <acme@redhat.com>

perf unwind: Do not put libunwind-{x86,aarch64} in FEATURE_TESTS_BASIC

As it is not normally available on x86_64 not being tested on test-all.c
but being in FEATURE_TESTS_BASIC ends up implying that those features
are present, which leads to trying to link with those libraries and a
build failure now that test-all.c is finally again building
successfully:

/usr/bin/ld: cannot find -lunwind-x86
/usr/bin/ld: cannot find -lunwind-aarch64
collect2: error: ld returned 1 exit status
make[3]: *** [Makefile:199: /tmp/build/perf/plugin_jbd2.so] Error 1
make[3]: *** Waiting for unfinished jobs....
/usr/bin/ld: cannot find -lunwind-x86
/usr/bin/ld: cannot find -lunwind-aarch64

So remove those features from there and explicitely test them.

And then move this patch to just before the last one that allows this to
be exposed, so that we keep the tree bisectable.

With all this in place we get, at this point:

$ ldd /tmp/build/perf/feature/test-libunwind.bin
linux-vdso.so.1 (0x00007fffa09c6000)
libunwind-x86_64.so.8 => /lib64/libunwind-x86_64.so.8 (0x00007fbcf4451000)
libunwind.so.8 => /lib64/libunwind.so.8 (0x00007fbcf4435000)
liblzma.so.5 => /lib64/liblzma.so.5 (0x00007fbcf440c000)
libelf.so.1 => /lib64/libelf.so.1 (0x00007fbcf43f2000)
libc.so.6 => /lib64/libc.so.6 (0x00007fbcf422c000)
libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007fbcf4211000)
/lib64/ld-linux-x86-64.so.2 (0x00007fbcf4491000)
libpthread.so.0 => /lib64/libpthread.so.0 (0x00007fbcf41ed000)
libz.so.1 => /lib64/libz.so.1 (0x00007fbcf41d3000)
$ cat /tmp/build/perf/feature/test-libunwind-x86.make.output
test-libunwind-x86.c:2:10: fatal error: libunwind-x86.h: No such file or directory
#include <libunwind-x86.h>
^~~~~~~~~~~~~~~~~
compilation terminated.
$ cat /tmp/build/perf/feature/test-libunwind-aarch64.make.output
test-libunwind-aarch64.c:2:10: fatal error: libunwind-aarch64.h: No such file or directory
#include <libunwind-aarch64.h>
^~~~~~~~~~~~~~~~~~~~~
compilation terminated.
$
$ ldd ~/bin/perf | grep unwind
libunwind-x86_64.so.8 => /lib64/libunwind-x86_64.so.8 (0x00007f5ceb24b000)
libunwind.so.8 => /lib64/libunwind.so.8 (0x00007f5ceb22f000)
$

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/n/tip-vs6kwqsvwk7oxhs6z9mq87pp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 1c3b28fd 12-Feb-2019 Arnaldo Carvalho de Melo <acme@redhat.com>

perf coresight: Do not test for libopencsd by default

Since it is not yet that generally available, avoid testing for the
presence of libcoresight in the fast path test-all.bin feature test.

# dnf search opencsd
No matches found.
# dnf search OpenCSD
No matches found.
# cat /etc/fedora-release
Fedora release 29 (Twenty Nine)
#

I.e. right now, in my system test-all.bin is failing all the time since
Fedora29 doesn't have libopencsd available:

$ cat /tmp/build/perf/feature/test-all.make.output
In file included from test-all.c:174:
test-libopencsd.c:2:10: fatal error: opencsd/c_api/opencsd_c_api.h: No such file or directory
#include <opencsd/c_api/opencsd_c_api.h>
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.

See:

6ab2b762befd ("perf build: Disable libbabeltrace check by default")

For the rationale, as soon as libopencsd becomes more generally packaged
and available, we do the same thing we did with babeltrace, enabling it
by default, as done in:

24787afbcd01 ("perf tools: Enable LIBBABELTRACE by default")

For now, to explicitely ask for opencsd, make sure you have it installed
and use:

make -C tools/perf CORESIGHT=1

The feature test output will be there as an empty file:

$ ls -la /tmp/build/perf/feature/test-libopencsd.make.output

Because the binary used for the feature check was successfully built:

$ ls -la /tmp/build/perf/feature/test-libopencsd.bin
-rwxrwxr-x. 1 acme acme 18336 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.bin
$ ldd /tmp/build/perf/feature/test-libopencsd.bin
linux-vdso.so.1 (0x00007fffe18cc000)
libopencsd_c_api.so.0 => /lib64/libopencsd_c_api.so.0 (0x00007fb8e67f6000)
libopencsd.so.0 => /lib64/libopencsd.so.0 (0x00007fb8e676f000)
libc.so.6 => /lib64/libc.so.6 (0x00007fb8e65a9000)
libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007fb8e6411000)
libm.so.6 => /lib64/libm.so.6 (0x00007fb8e628d000)
libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007fb8e6272000)
/lib64/ld-linux-x86-64.so.2 (0x00007fb8e6828000)
$

And the resulting perf binary will be linked with it:

-rw-rw-r--. 1 acme acme 0 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.make.output
$ ldd ~/bin/perf | grep opencsd
libopencsd_c_api.so.0 => /lib64/libopencsd_c_api.so.0 (0x00007fd43097f000)
libopencsd.so.0 => /lib64/libopencsd.so.0 (0x00007fd4308f8000)
$

To make sure this gets built before pushing things upstream I have a
ubuntu:19.04-x-arm64 container that has:

[root@quaco x-arm64]# grep CORESIGHT Dockerfile
ENV EXTRA_MAKE_ARGS=CORESIGHT=1
[root@quaco x-arm64]#

So that I always build with libopencsd before pushing things upstream.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: https://lkml.kernel.org/n/tip-20vyy39jw9jgrijesi30fgox@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 14541b1e 15-Nov-2018 Stanislav Fomichev <sdf@google.com>

perf build: Don't unconditionally link the libbfd feature test to -liberty and -lz

Current libbfd feature test unconditionally links against -liberty and -lz.
While it's required on some systems (e.g. opensuse), it's completely
unnecessary on the others, where only -lbdf is sufficient (debian).
This patch streamlines (and renames) the following feature checks:

feature-libbfd - only link against -lbfd (debian),
see commit 2cf9040714f3 ("perf tools: Fix bfd
dependency libraries detection")
feature-libbfd-liberty - link against -lbfd and -liberty
feature-libbfd-liberty-z - link against -lbfd, -liberty and -lz (opensuse),
see commit 280e7c48c3b8 ("perf tools: fix BFD
detection on opensuse")

(feature-liberty{,-z} were renamed to feature-libbfd-liberty{,z}
for clarity)

The main motivation is to fix this feature test for bpftool which is
currently broken on debian (libbfd feature shows OFF, but we still
unconditionally link against -lbfd and it works).

Tested on debian with only -lbfd installed (without -liberty); I'd
appreciate if somebody on the other systems can test this new detection
method.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/4dfc634cfcfb236883971b5107cf3c28ec8a31be.1542328222.git.sdf@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 2a07d814 05-Nov-2018 Alexey Budankov <alexey.budankov@linux.intel.com>

tools build feature: Check if libaio is available

This will be used by 'perf record' to speed up reading the perf ring
buffer.

Committer testing:

$ make -C tools/perf O=/tmp/build/perf
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build

Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ OFF ]
... libaudit: [ OFF ]
... libbfd: [ OFF ]
... libelf: [ on ]
... libnuma: [ OFF ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ OFF ]
... libpython: [ OFF ]
... libslang: [ on ]
... libcrypto: [ on ]
... libunwind: [ on ]
... libdw-dwarf-unwind: [ on ]
... zlib: [ on ]
... lzma: [ on ]
... get_cpuid: [ on ]
... bpf: [ on ]
... libaio: [ on ]

$ ls -la /tmp/build/perf/feature/test-libaio.*
-rwxrwxr-x. 1 acme acme 18296 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.bin
-rw-rw-r--. 1 acme acme 1165 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.d
-rw-rw-r--. 1 acme acme 0 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.make.output
$
$ grep -i aio /tmp/build/perf/FEATURE-DUMP
feature-libaio=1
$

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5fcda10c-6c63-68df-383a-c6d9e5d1f918@linux.intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 11c6cbe7 21-Nov-2018 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build feature: Check if eventfd() is available

A new 'perf bench epoll' will use this, and to disable it for older
systems, add a feature test for this API.

This is just a simple program that if successfully compiled, means that
the feature is present, at least at the library level, in a build that
sets the output directory to /tmp/build/perf (using O=/tmp/build/perf),
we end up with:

$ ls -la /tmp/build/perf/feature/test-eventfd*
-rwxrwxr-x. 1 acme acme 8176 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.bin
-rw-rw-r--. 1 acme acme 588 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.d
-rw-rw-r--. 1 acme acme 0 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.make.output
$ ldd /tmp/build/perf/feature/test-eventfd.bin
linux-vdso.so.1 (0x00007fff3bf3f000)
libc.so.6 => /lib64/libc.so.6 (0x00007fa984061000)
/lib64/ld-linux-x86-64.so.2 (0x00007fa984417000)
$ grep eventfd -A 2 -B 2 /tmp/build/perf/FEATURE-DUMP
feature-dwarf=1
feature-dwarf_getlocations=1
feature-eventfd=1
feature-fortify-source=1
feature-sync-compare-and-swap=1
$

The main thing here is that in the end we'll have -DHAVE_EVENTFD in
CFLAGS, and then the 'perf bench' entry needing that API can be
selectively pruned.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-wkeldwob7dpx6jvtuzl8164k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 8feb8efe 19-Nov-2018 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build feature: Check if get_current_dir_name() is available

As the namespace support code will use this, which is not available in
some non _GNU_SOURCE libraries such as Android's bionic used in my
container build tests (r12b and r15c at the moment).

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-x56ypm940pwclwu45d7jfj47@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# db42a21a 13-Jul-2018 Jakub Kicinski <kuba@kernel.org>

tools: include reallocarray feature test in FEATURE_TESTS_BASIC

perf propagates its feature check results to libbpf. This means
features for which perf probes must be a superset of libbpf's
required features. perf depends on FEATURE_TESTS_BASIC for its list
of features.

commit 531b014e7a2f ("tools: bpf: make use of reallocarray") added
reallocarray use to libbpf, make perf also perform the reallocarray
feature check.

Fixes: 531b014e7a2f ("tools: bpf: make use of reallocarray")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>


# bd476684 07-Mar-2018 Jiri Olsa <jolsa@kernel.org>

perf build: Add llvm/clang/cxx make tests into FEATURE_TESTS_EXTRA

So we can see the status when we build perf, like:

$ make LIBCLANGLLVM=1 VF=1
... cxx: [ on ]
... llvm: [ on ]
... llvm-version: [ on ]
... clang: [ on ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180307155020.32613-18-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# aa6292f4 17-Jan-2018 Mathieu Poirier <mathieu.poirier@linaro.org>

perf tools: Integrating the CoreSight decoding library

The Open CoreSight Decoding Library (openCSD) is a free and open library
to decode traces collected by the CoreSight hardware infrastructure.

This patch adds the required mechanic to recognise the presence of the
openCSD library on a system and set up miscellaneous flags to be used in
the compilation of the trace decoding feature.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: http://lkml.kernel.org/r/1516211539-5166-2-git-send-email-mathieu.poirier@linaro.org
Link: http://lkml.kernel.org/r/1516635644-24819-1-git-send-email-mathieu.poirier@linaro.org
[ Merged missing test-libopencsd.c file, provided later by Mathieu ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 25ab5abf 05-Dec-2017 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build feature: Check if pthread_barrier_t is available

As 'perf bench futex wake-parallel" will use this, which is not
available in older systems such as versions of the android NDK used in
my container build tests (r12b and r15c at the moment).

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: James Yang <james.yang@arm.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-1i7iv54in4wj08lwo55b0pzv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 86bcdb5a 18-Jul-2017 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add test for setns()

And provide an alternative implementation to keep perf building on older
distros as we're about to add initial support for namespaces.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-bqdwijunhjlvps1ardykhw1i@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 120010cb 01-Mar-2017 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add test for sched_getcpu()

Instead of trying to go on adding more ifdef conditions, do a feature
test and define HAVE_SCHED_GETCPU_SUPPORT instead, then use it to
provide the prototype. No need to change the stub, as it is already a
__weak symbol.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-yge89er9g90sc0v6k0a0r5tr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 2fedf79b 04-Dec-2016 Jiri Olsa <jolsa@kernel.org>

tools build: Move tabs to spaces where suitable

We've been hit several times by a Makefile bug where line indented by
tab was falsely considered as target command.

We prevent this by always using space indentation for everything except
for the target commands.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1480884178-8072-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 87095f7d 26-Sep-2016 Wang Nan <wangnan0@huawei.com>

tools build: Add feature detection for g++

Check if g++ is available. The result will be used by builtin clang and
LLVM support. Since LLVM requires C++11, this feature detector checks
std::move().

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1474874832-134786-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e26e63be 12-Jul-2016 Masami Hiramatsu <mhiramat@kernel.org>

perf build: Add sdt feature detection

This checks whether sys/sdt.h is available or not, which is required for
DTRACE_PROBE().

We can disable this feature by passing NO_SDT=1 when building.

This flag will be used for SDT test case and further SDT events in
perftools.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831795615.17065.17513820540591053933.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 1c1a3a47 11-Jul-2016 Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add feature detection for gelf_getnote()

That is not present on some libelf implementations, such as the one used
in Alpine Linux: libelf-0.8.13.

This ends up disabling the SDT code, that relies on this function.

One alternative would be to provide an weak fallback implementation or
the open coded variant used by the buildid sysfs notes reading code.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-82lh22ybedy9b9lych8xj12g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 2492c465 04-Jul-2016 Arnaldo Carvalho de Melo <acme@redhat.com>

perf build: Add feature detection for libelf's elf_getshdrstrndx()

That appeared after 0.140, and will be used in the SDT code, so, to
avoid bisection break on older systems, add a feature detection and
provide a stub with a pr_debug() to keep it building.

Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-80y0eldgweorqnwha9rvfxjr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 49247345 05-Apr-2016 Arnaldo Carvalho de Melo <acme@redhat.com>

perf probe: Check if dwarf_getlocations() is available

If not, tell the user that:

config/Makefile:273: Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157

And return -ENOTSUPP in die_get_var_range(), failing features that
need it, like the one pointed out above.

This fixes the build on older systems, such as Ubuntu 12.04.5.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vinson Lee <vlee@freedesktop.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9l7luqkq4gfnx7vrklkq4obs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# f9be7eef 10-May-2016 He Kuang <hekuang@huawei.com>

perf build: Add build-test for debug-frame on arm/arm64

Debug-frame for remote platforms is not related to the host platform, so
we should test each platform separately.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1462866037-30382-5-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# b1d96000 10-May-2016 He Kuang <hekuang@huawei.com>

perf build: Add build-test for libunwind cross-platforms support

Currently only test for local libunwind. We should check all supported
platforms so we can use them to parse perf.data with callchain info on
different machines.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1462866037-30382-4-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# bd0419e2 05-Apr-2016 Arnaldo Carvalho de Melo <acme@redhat.com>

perf probe: Check if dwarf_getlocations() is available

If not, tell the user that:

config/Makefile:273: Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157

And return -ENOTSUPP in die_get_var_range(), failing features that
need it, like the one pointed out above.

This fixes the build on older systems, such as Ubuntu 12.04.5.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vinson Lee <vlee@freedesktop.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9l7luqkq4gfnx7vrklkq4obs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 8ee46460 30-Nov-2015 Stephane Eranian <eranian@google.com>

perf build: Add libcrypto feature detection

Will be used to generate build-ids in the jitdump code.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Carl Love <cel@us.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John McCutchan <johnmccutchan@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1448874143-7269-3-git-send-email-eranian@google.com
[ tools/perf/Makefile.perf comment about NO_LIBCRYPTO and added it to tests/make ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 76c4aaec 28-Jan-2016 Jiri Olsa <jolsa@redhat.com>

perf build: Fix feature-dump checks, we need to test all features

I see problem with test-all case speedup, because it does not
comprise checks for 32bits compilations, fix it.

The problem could be noticed by calling:

make -C tools/perf feature-dump

That would end up misdetecting the feature-compile-x32, that, building
using 'gcc -mx32' needs stub headers not present in a fedora 23 devel
machine and thus fail to compile, but ended up appearing as detected,
i.e. present in tools/perf/FEATURE-DUMP as 'feature-compile-x32=1'.

With this fix it correctly appears as 'feature-compile-x32=0' and if we
uninstall the libc devel files for 32 bits (glibc-devel.i686), then the
relevant variable is flipped from 'feature-compile-32=1' to
'feature-compile-32=0'.

The same things happened for bionic and libbabeltrace, that were
misdetected because the are no tested in test-all.c

Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-u0sjaddf1r9m8icpd98ry7fz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 9fd4186a 25-Jan-2016 Wang Nan <wangnan0@huawei.com>

tools build: Allow subprojects select all feature checkers

Put feature checkers not in original FEATURE_TESTS to a new list and
allow subproject select all feature checkers by setting FEATURE_TESTS to
'all'.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1453715801-7732-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 936d120d 23-Dec-2015 Jiri Olsa <jolsa@kernel.org>

tools build feature: Use value assignment form for FEATURE-DUMP file

Changing the contents of the FEATURE-DUMP file, so it looks like:

feature-backtrace=1
feature-dwarf=0
feature-fortify-source=1
feature-sync-compare-and-swap=0

This way it could get included in sub projects, so they won't be forced
to redo features detection.

Also now storing the complete set of features.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama <pi3orama@163.com>
Link: http://lkml.kernel.org/r/1450893514-9158-5-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# c6a5f88f 23-Dec-2015 Jiri Olsa <jolsa@kernel.org>

tools build feature: Introduce feature_assign macro

The feature_assign macro generates feature value
assignment for name, like:

$(call feature_assign,dwarf) == feature-dwarf=1

This will be used more in following patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama <pi3orama@163.com>
Link: http://lkml.kernel.org/r/1450893514-9158-4-git-send-email-jolsa@kernel.org
[ Rename it to feature_assign, the original shorter name was misleading, to say the least ;-) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 76ee2ff3 23-Dec-2015 Jiri Olsa <jolsa@kernel.org>

tools build feature: Move dwarf post unwind choice output into perf

We decide what dwarf unwind to choose way after the Makefile.feature
makefile is included. The $(dwarf-post-unwind) is not even set at that
time. For the same reason it was never included in FEATURE-DUMP file.

Moving it into perf VF=1 verbose display.

$ make VF=1
BUILD: Doing 'make -j4' parallel build
Auto-detecting system features:
... dwarf: [ on ]
...
... LIBUNWIND_DIR:
... LIBDW_DIR:
... DWARF post unwind library: libunwind
...

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama <pi3orama@163.com>
Link: http://lkml.kernel.org/r/1450893514-9158-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# d0018b49 23-Dec-2015 Jiri Olsa <jolsa@kernel.org>

tools build feature: Fix feature_check_display_code typo

This function is cursed.. ;-)

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama <pi3orama@163.com>
Link: http://lkml.kernel.org/r/1450893514-9158-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 1925459b 15-Dec-2015 Josh Poimboeuf <jpoimboe@redhat.com>

tools build: Fix feature Makefile issues with 'O='

When building perf binaries outside the source tree with 'make O=<dir>',
the auto-detected features get re-tested for every build, which is
unnecessary and inconsistent with the behavior seen when building
directly in the source tree.

Another issue is that 'make O=<dir> clean' doesn't remove the feature
files from the object tree.

Fix these problems by looking for the binaries in the $(OUTPUT)
directory.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/113bd01530e9761778c60a75a96c65fc59860f68.1450193761.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 26bc9b2d 13-Dec-2015 Josh Poimboeuf <jpoimboe@redhat.com>

perf build: Remove unnecessary line in Makefile.feature

This line always silently fails because it doesn't add the 'test-'
prefix to the .bin file.

And it seems to be unnecessary anyway: the line immediately after it
does all the individual feature checks.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/554a05c18af564ba015c9e68f25730126e0f4acb.1449965119.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# ed63f34c 13-Oct-2015 Wang Nan <wangnan0@huawei.com>

perf tools: Make perf depend on libbpf

By adding libbpf into perf's Makefile, this patch enables perf to build
libbpf if libelf is found and neither NO_LIBELF nor NO_LIBBPF is set.

The newly introduced code is similar to how libapi and libtraceevent
are wired into Makefile.perf.

MANIFEST is also updated for 'make perf-*-src-pkg'.

Append make_no_libbpf to tools/perf/tests/make.

The 'bpf' feature check is appended into default FEATURE_TESTS and
FEATURE_DISPLAY, so perf will check the API version of bpf in
/path/to/kernel/include/uapi/linux/bpf.h. Which should not fail except
when we are trying to port this code to an old kernel.

Error messages are also updated to notify users about the lack of BPF
support in 'perf record' if libelf is missing or the BPF API check
failed.

tools/lib/bpf is added to TAG_FOLDERS to allow us to navigate libbpf
files when working on perf using tools/perf/tags.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-2-git-send-email-wangnan0@huawei.com
[ Document NO_LIBBPF in Makefile.perf, noted by Jiri Olsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 13e96db6 20-Sep-2015 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Allow setting the feature detection user

We will use the tools/build/ autodetection in the eBPF patchkit
and it is currently sharing the output directory with perf, that
also uses the feature detection logic.

As we keep state in the output directory, so that we can avoid running
all the tests again, we need to have different filenames for the files
used in this state, allow doing that via the FEATURE_USER variable, to
be set alongside the existing FEATURE_{TEST,DISPLAY} variables.

v2: Fix comment describing the FEATURE_DUMP filename to make sure where
it is created, precisely at $(OUTPUT)FEATURE-DUMP$(FEATURE_USER).
Pointed out by Jiri.

Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/n/tip-fdbev0vrn3x6idqc3ajbnvcb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 6076e2a4 21-Sep-2015 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Fixup feature detection display function name

Cut'n'paste mistake, it should eval the name of the function
defined right next to it, in the next line, fix it.

Before:

$ make -C tools/lib/bpf/
make: Entering directory '/home/git/linux/tools/lib/bpf'

Auto-detecting system features:
... libelf: [ on ]
... libelf-getphdrnum: [ on ]
... libelf-mmap: [ on ]
... bpf: [ on ]
<SNIP>

After:

$ make -C tools/lib/bpf/
make: Entering directory '/home/git/linux/tools/lib/bpf'

Auto-detecting system features:
... libelf: [ on ]
... libelf-getphdrnum: [ OFF ]
... libelf-mmap: [ OFF ]
... bpf: [ on ]
<SNIP>

Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Fixes: 58d4f00ff13f ("perf build: Fix feature_check name clash")
Link: http://lkml.kernel.org/n/tip-dzu1c4sruukgfq5d5b1c4r30@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# b0063dbf 16-Sep-2015 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add test for presence of __get_cpuid() gcc builtin

The auxtrace code needed by Intel PT uses the __get_cpuid() gcc builtin,
that is not present in old systems, breaking the build.

Add a test to check for that builtin and disable AUXTRACE in those
systems.

[acme@rhel5 linux]$ make NO_LIBPERL=1 -C tools/perf O=/tmp/build/perf install-bin
make: Entering directory `/home/acme/git/linux/tools/perf'
BUILD: Doing 'make -j2' parallel build

Auto-detecting system features:
<SNIP>
... lzma: [ on ]
... get_cpuid: [ OFF ]
<SNIP>
config/Makefile:630: Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc
MKDIR /tmp/build/perf/util/
<SNIP>

This fixes the build on old systems such as RHEL/CentOS 5.11.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Cc: Vinson Lee <vlee@twopensource.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4puslul0jltoodzpx9r4sje@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# f8ac8606 16-Sep-2015 Arnaldo Carvalho de Melo <acme@redhat.com>

tools build: Add test for presence of numa_num_possible_cpus() in libnuma

The existing numa test checks only if numa.h and numa_available() are
present, but that can be satisfied with an old libnuma that is not
enough for the 'perf bench numa' entry, so add a test to check for that:

[acme@rhel5 linux]$ make NO_AUXTRACE=1 NO_LIBPERL=1 -C tools/perf O=/tmp/build/perf install-bin
make: Entering directory `/home/acme/git/linux/tools/perf'
BUILD: Doing 'make -j2' parallel build

Auto-detecting system features:
... libelf: [ on ]
... libnuma: [ on ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ on ]

<SNIP>
config/Makefile:577: Old numa library found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev >= 2.0.8
INSTALL binaries
<SNIP>

This fixes the build on old systems such as RHEL/CentOS 5.11.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Cc: Vinson Lee <vlee@twopensource.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-zqriqkezppi2de2iyjin1tnc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 8135c8c7 17-May-2015 Wang Nan <wangnan0@huawei.com>

tools build: Change FEATURE_TESTS and FEATURE_DISPLAY to weak binding

Replace strong binding of FEATURE_TESTS and FEATURE_DISPLAY by weak
binding. This patch enables other makefiles which include
tools/build/Makefile.feature enable only limited feathres to check.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: pi3orama@163.com
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1431860222-61636-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 6c6f0f61 04-Mar-2015 Jiri Olsa <jolsa@kernel.org>

tools build: Add feature check for lzma library

Will be used to decompress 'xz' objects. The check detects
the liblzma.so devel library normally delivered by xz package.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>


# e6c76d62 01-Mar-2015 Jiri Olsa <jolsa@kernel.org>

perf build: Move feature checks code under tools/build

Moving feature checks code under tools/build directory.

Changing also $feature_dir to point to new feature directory location
and perf Makefiles to include Makefile.feature from new location.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <david.ahern@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-3lamtb30dhf4wo99y1n8kxg0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>