linux.git/tools/perf/Makefile.config, branch v6.7

perf build: Disable BPF skeletons if clang version is < 12.0.1

2023-10-28T02:27:33+00:00

While building on a wide range of distros and clang versions it was
noticed that at least version 12.0.1 (noticed on Alpine 3.15 with
"Alpine clang version 12.0.1") is needed to not fail with BTF generation
errors such as:

Debian:10

  Debian clang version 11.0.1-2~deb10u1:

    CLANG   /tmp/build/perf/util/bpf_skel/.tmp/sample_filter.bpf.o
  
    GENSKEL /tmp/build/perf/util/bpf_skel/sample_filter.skel.h
  libbpf: failed to find BTF for extern 'bpf_cast_to_kern_ctx' [21] section: -2
  Error: failed to open BPF object file: No such file or directory
  make[2]: *** [Makefile.perf:1121: /tmp/build/perf/util/bpf_skel/sample_filter.skel.h] Error 254
  make[2]: *** Deleting file '/tmp/build/perf/util/bpf_skel/sample_filter.skel.h'

Amazon Linux 2:

  clang version 11.1.0 (Amazon Linux 2 11.1.0-1.amzn2.0.2)

    GENSKEL /tmp/build/perf/util/bpf_skel/sample_filter.skel.h
  libbpf: elf: skipping unrecognized data section(18) .eh_frame
  libbpf: elf: skipping relo section(19) .rel.eh_frame for section(18) .eh_frame
  libbpf: failed to find BTF for extern 'bpf_cast_to_kern_ctx' [21] section: -2
  Error: failed to open BPF object file: No such file or directory
  make[2]: *** [/tmp/build/perf/util/bpf_skel/sample_filter.skel.h] Error 254
  make[2]: *** Deleting file `/tmp/build/perf/util/bpf_skel/sample_filter.skel.h'

Ubuntu 20.04:

  clang version 10.0.0-4ubuntu1

    CLANG   /tmp/build/perf/util/bpf_skel/.tmp/augmented_raw_syscalls.bpf.o
    GENSKEL /tmp/build/perf/util/bpf_skel/bench_uprobe.skel.h
    GENSKEL /tmp/build/perf/util/bpf_skel/bperf_leader.skel.h
  libbpf: sec '.reluprobe': corrupted symbol #27 pointing to invalid section #65522 for relo #0
    GENSKEL /tmp/build/perf/util/bpf_skel/bperf_follower.skel.h
  Error: failed to open BPF object file: BPF object format invalid
  make[2]: *** [Makefile.perf:1121: /tmp/build/perf/util/bpf_skel/bench_uprobe.skel.h] Error 95
  make[2]: *** Deleting file '/tmp/build/perf/util/bpf_skel/bench_uprobe.skel.h'

So check if the version is at least 12.0.1 otherwise disable building
BPF skels and provide a message about it, continuing the build.

The message, when running on amazonlinux:2:

  Makefile.config:698: Warning: Disabled BPF skeletons as reliable BTF generation needs at least clang version 12.0.1

Signed-off-by: Arnaldo Carvalho de Melo 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/ZTvGx/Ou6BVnYBqi@kernel.org
Signed-off-by: Namhyung Kim

perf build: Default BUILD_BPF_SKEL, warn/disable for missing deps

2023-09-18T23:46:26+00:00

LIBBPF is dependent on zlib so move the NO_ZLIB and feature check
early to avoid statically building when zlib is disabled. This avoids
a linkage failure with perf and static libbpf when zlib isn't
specified.

Move BUILD_BPF_SKEL logic to one place and if not defined set
BUILD_BPF_SKEL to 1. Detect dependencies of building with BPF
skeletons and warn/disable if the dependencies aren't present.

Change Makefile.perf to contain BPF skeleton logic dependent on the
Makefile.config result and refresh the comment about BUILD_BPF_SKEL.

Signed-off-by: Ian Rogers 
Tested-by: Namhyung Kim 
Cc: James Clark 
Cc: Nick Terrell 
Cc: Patrice Duroux 
Cc: Nick Desaulniers 
Cc: Andrii Nakryiko 
Cc: Nathan Chancellor 
Cc: Kajol Jain 
Cc: Athira Rajeev 
Cc: Tiezhu Yang 
Cc: Tom Rix 
Cc: llvm@lists.linux.dev
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230914211948.814999-3-irogers@google.com
Signed-off-by: Namhyung Kim

perf parse-events: Remove BPF event support

2023-08-15T19:41:48+00:00

New features like the BPF --filter support in perf record have made the
BPF event functionality somewhat redundant. As shown by commit
fcb027c1a4f6 ("perf tools: Revert enable indices setting syntax for BPF
map") and commit 14e4b9f4289a ("perf trace: Raw augmented syscalls fix
libbpf 1.0+ compatibility") the BPF event support hasn't been well
maintained and it adds considerable complexity in areas like event
parsing, not least as '/' is a separator for event modifiers as well as
in paths.

This patch removes support in the event parser for BPF events and then
the associated functions are removed. This leads to the removal of whole
source files like bpf-loader.c.  Removing support means that augmented
syscalls in perf trace is broken, this will be fixed in a later commit
adding support using BPF skeletons.

The removal of BPF events causes an unused label warning from flex
generated code, so update build to ignore it:

  ```
  util/parse-events-flex.c:2704:1: error: label ‘find_rule’ defined but not used [-Werror=unused-label]
  2704 | find_rule: /* we branch to this label when backing up */
  ```

Committer notes:

Extracted from a larger patch that was also removing the support for
linking with libllvm and libclang, that were an alternative to using an
external clang execution to compile the .c event source code into BPF
bytecode.

Testing it:

  # perf trace -e /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c
  event syntax error: '/home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c'
                        \___ Bad event or PMU

  Unabled to find PMU or event on a PMU of 'home'

  Initial error:
  event syntax error: '/home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c'
                        \___ Cannot find PMU `home'. Missing kernel support?
  Run 'perf list' for a list of valid events

   Usage: perf trace [] []
      or: perf trace [] --  []
      or: perf trace record [] []
      or: perf trace record [] --  []

      -e, --event    event/syscall selector. use 'perf list' to list available events
  #

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andrii Nakryiko 
Cc: Anshuman Khandual 
Cc: Athira Rajeev 
Cc: Brendan Gregg 
Cc: Carsten Haitzler 
Cc: Eduard Zingerman 
Cc: Fangrui Song 
Cc: He Kuang 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: Naveen N. Rao 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Tiezhu Yang 
Cc: Tom Rix 
Cc: Wang Nan 
Cc: Wang ShaoBo 
Cc: Yang Jihong 
Cc: Yonghong Song 
Cc: YueHaibing 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230810184853.2860737-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 

Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Remove support for embedding clang for compiling BPF events (-e foo.c)

2023-08-15T19:41:48+00:00

This never was in the default build for perf, is difficult to maintain
as it uses clang/llvm internals so ditch it, keeping, for now, the
external compilation of .c BPF into .o bytecode and its subsequent
loading, that is also going to be removed, do it separately to help
bisection and to properly document what is being removed and why.

Committer notes:

Extracted from a larger patch and removed some leftovers, namely
deleting these now unused feature tests:

    tools/build/feature/test-clang.cpp
    tools/build/feature/test-cxx.cpp
    tools/build/feature/test-llvm-version.cpp
    tools/build/feature/test-llvm.cpp

Testing the use of BPF events after applying this patch:

To use the external clang/llvm toolchain to compile a .c event and then
use libbpf to load it, to get the syscalls:sys_enter_open* tracepoints
and read the filename pointer, putting it into the ring buffer right
after the usual tracepoint payload for 'perf trace' to then print it:

  [root@quaco ~]# perf trace -e /home/acme/git/perf-tools-next/tools/perf/examples/bpf/augmented_raw_syscalls.c,open* --max-events=10
     0.000 systemd-oomd/959 openat(dfd: CWD, filename: "/proc/meminfo", flags: RDONLY|CLOEXEC) = 12
     0.083 abrt-dump-jour/1453 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
     0.063 abrt-dump-jour/1454 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
     0.082 abrt-dump-jour/1455 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
   250.124 systemd-oomd/959 openat(dfd: CWD, filename: "/proc/meminfo", flags: RDONLY|CLOEXEC) = 12
   250.521 systemd-oomd/959 openat(dfd: CWD, filename: "/sys/fs/cgroup/user.slice/user-1000.slice/user@1000.service/app.slice/memory.pressure", flags: RDONLY|CLOEXEC) = 12
   251.047 systemd-oomd/959 openat(dfd: CWD, filename: "/sys/fs/cgroup/user.slice/user-1000.slice/user@1000.service/app.slice/memory.current", flags: RDONLY|CLOEXEC) = 12
   251.162 systemd-oomd/959 openat(dfd: CWD, filename: "/sys/fs/cgroup/user.slice/user-1000.slice/user@1000.service/app.slice/memory.min", flags: RDONLY|CLOEXEC) = 12
   251.242 systemd-oomd/959 openat(dfd: CWD, filename: "/sys/fs/cgroup/user.slice/user-1000.slice/user@1000.service/app.slice/memory.low", flags: RDONLY|CLOEXEC) = 12
   251.353 systemd-oomd/959 openat(dfd: CWD, filename: "/sys/fs/cgroup/user.slice/user-1000.slice/user@1000.service/app.slice/memory.swap.current", flags: RDONLY|CLOEXEC) = 12
  [root@quaco ~]#

Same thing, but with a prebuilt .o BPF bytecode:

  [root@quaco ~]# perf trace -e /home/acme/git/perf-tools-next/tools/perf/examples/bpf/augmented_raw_syscalls.o,open* --max-events=10
     0.000 systemd-oomd/959 openat(dfd: CWD, filename: "/proc/meminfo", flags: RDONLY|CLOEXEC) = 12
     0.083 abrt-dump-jour/1453 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
     0.083 abrt-dump-jour/1455 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
     0.062 abrt-dump-jour/1454 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 4
   249.985 systemd-oomd/959 openat(dfd: CWD, filename: "/proc/meminfo", flags: RDONLY|CLOEXEC) = 12
   466.763 thermald/1234 openat(dfd: CWD, filename: "/sys/class/powercap/intel-rapl/intel-rapl:0/intel-rapl:0:2/energy_uj") = 13
   467.145 thermald/1234 openat(dfd: CWD, filename: "/sys/class/powercap/intel-rapl/intel-rapl:0/energy_uj") = 13
   467.311 thermald/1234 openat(dfd: CWD, filename: "/sys/class/thermal/thermal_zone2/temp") = 13
   500.040 cgroupify/24006 openat(dfd: 4, filename: ".", flags: RDONLY|CLOEXEC|DIRECTORY|NONBLOCK) = 5
   500.295 cgroupify/24006 openat(dfd: 4, filename: "24616/cgroup.procs") = 5
  [root@quaco ~]#

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andrii Nakryiko 
Cc: Anshuman Khandual 
Cc: Athira Rajeev 
Cc: Brendan Gregg 
Cc: Carsten Haitzler 
Cc: Eduard Zingerman 
Cc: Fangrui Song 
Cc: He Kuang 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: "Naveen N. Rao" 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Tiezhu Yang 
Cc: Tom Rix 
Cc: Wang Nan 
Cc: Wang ShaoBo 
Cc: Yang Jihong 
Cc: Yonghong Song 
Cc: YueHaibing 
Link: https://lore.kernel.org/lkml/ZNZWsAXg2px1sm2h@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Support llvm and clang support compiled in

2023-08-03T20:01:28+00:00

Perf build suports llvm and clang support compiled in.
Test case 56 builtin clang support provides a test case
which is always skipped.

Link perf with the latest llvm and clang libraries and
enable this test case.

Use 'make LIBCLANGLLVM=1' to include this support.

V2: Add Library patch before -lclang-cpp

Output before:

  # ./perf test 56
  56: builtin clang support                  :
  56.1: builtin clang compile C source to IR : Skip (not compiled in)
  56.2: builtin clang compile C source to ELF object: Skip (not compiled in)

Output after:

  # ./perf test 56
  56: builtin clang support                          :
  56.1: builtin clang compile C source to IR         : Ok
  56.2: builtin clang compile C source to ELF object : Ok
  #

From Ian Rogers:

  Build tested with LLVM 14 and 15 using:
  BUILD_BPF_SKEL=1 LIBCLANGLLVM=1 LLVM_CONFIG=llvm-config-14
  BUILD_BPF_SKEL=1 LIBCLANGLLVM=1 LLVM_CONFIG=llvm-config-15

Signed-off-by: Thomas Richter 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Ian Rogers 
Cc: Heiko Carstens 
Cc: Jiri Olsa 
Cc: Sumanth Korikkar 
Cc: Sven Schnelle 
Cc: Thomas Richter 
Cc: Vasily Gorbik 
Cc: Wang Nan 
Link: https://lore.kernel.org/r/20230725150347.3479291-2-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Add Wextra for C++ compilation

2023-07-28T22:01:17+00:00

Commit d58ac0bf8d1e ("perf build: Add clang and llvm compile and
linking support") added -Wall and -Wno-strict-aliasing for CXXFLAGS,
but not -Wextra. -Wno-strict-aliasing is no longer necessary, adding
-Wextra for CXXFLAGS requires adding -Wno-unused-parameter clang.cpp
and clang-test.cpp for LIBCLANGLLVM=1 to build.

Signed-off-by: Ian Rogers 
Acked-by: James Clark 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andrii Nakryiko 
Cc: Eduard Zingerman 
Cc: Gaosheng Cui 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Rob Herring 
Cc: Tom Rix 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230728064917.767761-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Don't always set -funwind-tables and -ggdb3

2023-07-28T22:01:17+00:00

Commit 6a40cd90f5deb6de ("perf tools: Add libunwind dependency for DWARF
CFI unwinding") added libunwind support but also -funwind-tables and
-ggdb3 to the standard build. These build flags aren't necessary so
remove, set -g when DEBUG is enabled for the build.

Signed-off-by: Ian Rogers 
Acked-by: James Clark 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andrii Nakryiko 
Cc: Eduard Zingerman 
Cc: Gaosheng Cui 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Rob Herring 
Cc: Tom Rix 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230728064917.767761-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Add LTO build option

2023-07-24T21:24:25+00:00

Add an LTO build option, that sets the appropriate CFLAGS and CXXFLAGS
values.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Carsten Haitzler 
Cc: Fangrui Song 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Tom Rix 
Cc: Xing Zhengjun 
Cc: Yang Jihong 
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230724201247.748146-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Fix library not found error when using CSLIBS

2023-07-11T14:46:35+00:00

-L only specifies the search path for libraries directly provided in the
link line with -l. Because -lopencsd isn't specified, it's only linked
because it's a dependency of -lopencsd_c_api. Dependencies like this are
resolved using the default system search paths or -rpath-link=... rather
than -L. This means that compilation only works if OpenCSD is installed
to the system rather than provided with the CSLIBS (-L) option.

This could be fixed by adding -Wl,-rpath-link=$(CSLIBS) but that is less
conventional than just adding -lopencsd to the link line so that it uses
-L. -lopencsd seems to have been removed in commit ed17b1914978eddb
("perf tools: Drop requirement for libstdc++.so for libopencsd check")
because it was thought that there was a chance compilation would work
even if it didn't exist, but I think that only applies to libstdc++ so
there is no harm to add it back. libopencsd.so and libopencsd_c_api.so
would always exist together.

Testing
=======

The following scenarios now all work:

 * Cross build with OpenCSD installed
 * Cross build using CSLIBS=...
 * Native build with OpenCSD installed
 * Native build using CSLIBS=...
 * Static cross build with OpenCSD installed
 * Static cross build with CSLIBS=...

Committer testing:

  ⬢[acme@toolbox perf-tools]$ alias m
  alias m='make -k BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools -C tools/perf install-bin && git status && perf test python ;  perf record -o /dev/null sleep 0.01 ; perf stat --null sleep 0.01'
  ⬢[acme@toolbox perf-tools]$ ldd ~/bin/perf | grep csd
  	libopencsd_c_api.so.1 => /lib64/libopencsd_c_api.so.1 (0x00007fd49c44e000)
  	libopencsd.so.1 => /lib64/libopencsd.so.1 (0x00007fd49bd56000)
  ⬢[acme@toolbox perf-tools]$ cat /etc/redhat-release
  Fedora release 36 (Thirty Six)
  ⬢[acme@toolbox perf-tools]$

Fixes: ed17b1914978eddb ("perf tools: Drop requirement for libstdc++.so for libopencsd check")
Reported-by: Radhey Shyam Pandey 
Signed-off-by: James Clark 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Radhey Shyam Pandey 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Uwe Kleine-König 
Cc: coresight@lists.linaro.org
Closes: https://lore.kernel.org/linux-arm-kernel/56905d7a-a91e-883a-b707-9d5f686ba5f1@arm.com/
Link: https://lore.kernel.org/all/36cc4dc6-bf4b-1093-1c0a-876e368af183@kleine-koenig.org/
Link: https://lore.kernel.org/r/20230707154546.456720-1-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf test: Fix a compile error on pe-file-parsing.c

2023-06-27T19:14:38+00:00

The dso__find_symbol_by_name() should be have idx pointer argument.
Found during the build-test.

  $ make build-test
  ...
    CC      /tmp/tmp.6JwPK1xbWG/tests/pe-file-parsing.o
  tests/pe-file-parsing.c: In function ‘run_dir’:
  tests/pe-file-parsing.c:64:15: error: too few arguments to function ‘dso__find_symbol_by_name’
     64 |         sym = dso__find_symbol_by_name(dso, "main");
        |               ^~~~~~~~~~~~~~~~~~~~~~~~
  In file included from tests/pe-file-parsing.c:16:
  /usr/local/google/home/namhyung/project/linux/tools/perf/util/symbol.h:135:16: note: declared here
    135 | struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx);
        |                ^~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 259dce914e93 ("perf symbol: Remove symbol_name_rb_node")
Acked-by: Ian Rogers 
Cc: Peter Zijlstra 
Cc: Adrian Hunter 
Cc: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Ingo Molnar 
Link: https://lore.kernel.org/r/20230627063257.549005-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim