linux-stable.git/tools/build/feature, branch v6.4

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

2023-04-04T16:18:17+00:00

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 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/ZCwv4z5Dh%2FdHUMG6@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo

tools build: Add feature test for abi::__cxa_demangle

2023-03-14T11:29:46+00:00

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 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andres Freund 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Martin Liška 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Pavithra Gurushankar 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Roberto Sassu 
Cc: Stephane Eranian 
Cc: Tiezhu Yang 
Cc: Tom Rix 
Cc: Yang Jihong 
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230311065753.3012826-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Remove libbpf pre-1.0 feature tests

2023-03-14T11:29:45+00:00

The feature tests were necessary for libbpf pre-1.0, but as the libbpf
implies at least 1.0 we can remove these now.

Committer notes:

Modified tools/perf/Makefile.config to better reflect the reason for
failure when the libbpf present is < 1.0 and LIBBPF_DYNAMIC=1 was asked
for.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Tested-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: Christy Lee 
Cc: Ingo Molnar 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Roberto Sassu 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230116010115.490713-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

tools build: Pass libbpf feature only if libbpf 1.0+

2023-03-14T11:29:33+00:00

libbpf 1.0 represented a cleanup and stabilization of APIs. Simplify
development by only passing the feature test if libbpf 1.0 is installed.

Committer notes:

Change 'make -C tools/perf build-test' so that the LIBBPF_DYNAMIC=1 test
runs only if libbpf is >= 1.0.

Signed-off-by: Ian Rogers 
Tested-by: Jiri Olsa 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: Christy Lee 
Cc: Ingo Molnar 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Roberto Sassu 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230116010115.490713-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

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

2022-10-25T20:40:48+00:00

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

tools build: Switch to new openssl API for test-libcrypto

2022-08-10T13:44:02+00:00

Switch to new EVP API for detecting libcrypto, as Fedora 36 returns an
error when it encounters the deprecated function MD5_Init() and the others.

The error would be interpreted as missing libcrypto, while in reality it is
not.

Fixes: 6e8ccb4f624a73c5 ("tools/bpf: properly account for libbfd variations")
Signed-off-by: Roberto Sassu 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Daniel Borkmann 
Cc: Ingo Molnar 
Cc: John Fastabend 
Cc: KP Singh 
Cc: llvm@lists.linux.dev
Cc: Martin KaFai Lau 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Nick Terrell 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Song Liu 
Cc: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20220719170555.2576993-4-roberto.sassu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

Revert "perf build: Suppress openssl v3 deprecation warnings in libcrypto feature test"

2022-08-10T13:44:02+00:00

This reverts commit 10fef869a58e37ec649b61eddab545f2da57a79b.

Because a proper fix was submitted.

Signed-off-by: Arnaldo Carvalho de Melo

tools, build: Retry detection of bfd-related features

2022-08-10T13:44:01+00:00

While separate features have been defined to determine which linking flags
are required to use libbfd depending on the distribution (libbfd,
libbfd-liberty and libbfd-liberty-z), the same has not been done for other
features requiring linking to libbfd.

For example, disassembler-four-args requires linking to libbfd too, but it
should use the right linking flags. If not all the required ones are
specified, e.g. -liberty, detection will always fail even if the feature is
available.

Instead of creating new features, similarly to libbfd, simply retry
detection with the different set of flags until detection succeeds (or
fails, if the libraries are missing). In this way, feature detection is
transparent for the users of this building mechanism (e.g. perf), and those
users don't have for example to set an appropriate value for the
FEATURE_CHECK_LDFLAGS-disassembler-four-args variable.

The number of retries and features for which the retry mechanism is
implemented is low enough to make the increase in the complexity of
Makefile negligible.

Tested with perf and bpftool on Ubuntu 20.04.4 LTS, Fedora 36 and openSUSE
Tumbleweed.

Committer notes:

Do the retry for disassembler-init-styled as well.

Signed-off-by: Roberto Sassu 
Cc: Alexei Starovoitov 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: Daniel Borkmann 
Cc: Ingo Molnar 
Cc: John Fastabend 
Cc: KP Singh 
Cc: Martin KaFai Lau 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Nick Terrell 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Song Liu 
Cc: Stanislav Fomichev 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20220719170555.2576993-1-roberto.sassu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Suppress openssl v3 deprecation warnings in libcrypto feature test

2022-08-02T19:32:28+00:00

With OpenSSL v3 installed, the libcrypto feature check fails as it use the
deprecated MD5_* API (and is compiled with -Werror). The error message is
as follows.

$ make tools/perf
```
Makefile.config:778: No libcrypto.h found, disables jitted code injection,
please install openssl-devel or libssl-dev

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

This is very confusing because the suggested library (on my Ubuntu 20.04
it is libssl-dev) is already installed. As the test only checks for the
presence of libcrypto, this commit suppresses the deprecation warning to
allow the test to pass.

Signed-off-by: Zixuan Tan 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: Daniel Borkmann 
Cc: John Fastabend 
Cc: KP Singh 
Cc: Martin KaFai Lau 
Cc: Nick Terrell 
Cc: Song Liu 
Cc: Yonghong Song 
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20220625153439.513559-1-tanzixuan.me@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

tools build: Add feature test for init_disassemble_info API changes

2022-08-01T18:29:10+00:00

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 
Acked-by: Quentin Monnet 
Cc: Alexei Starovoitov 
Cc: Ben Hutchings 
Cc: Jiri Olsa 
Cc: Quentin Monnet 
Cc: Sedat Dilek 
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