kernel/tools/perf/util/llvm-utils.c, branch linux-rolling-stable

perf parse-events: Remove BPF event support

2023-08-15T19:41:48Z

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: Replace deprecated -target with --target= for Clang

2023-06-27T19:13:22Z

-target has been deprecated since Clang 3.4 in 2013. Use the preferred --target=bpf form instead. This matches how we use --target= in scripts/Makefile.clang. Signed-off-by: Fangrui Song Acked-by: Yonghong Song Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: llvm@lists.linux.dev Cc: Ingo Molnar Cc: bpf@vger.kernel.org Link: https://github.com/llvm/llvm-project/commit/274b6f0c87a6a1798de0a68135afc7f95def6277 Link: https://lore.kernel.org/r/20230624002708.1907962-1-maskray@google.com [ resolved a conflict with GEN_VMLINUX_H changes ] Signed-off-by: Namhyung Kim

perf llvm: Fix inadvertent file creation

2023-01-19T16:23:26Z

The LLVM template is first echo-ed into command_out and then command_out executed. The echo surrounds the template with double quotes, however, the template itself may contain quotes. This is generally innocuous but in tools/perf/tests/bpf-script-test-prologue.c we see: ... SEC("func=null_lseek file->f_mode offset orig") ... where the first double quote ends the double quote of the echo, then the > redirects output into a file called f_mode. To avoid this inadvertent behavior substitute redirects and similar characters to be ASCII control codes, then substitute the output in the echo back again. Fixes: 5eab5a7ee032acaa ("perf llvm: Display eBPF compiling command in debug output") Signed-off-by: Ian Rogers Cc: Alexander Shishkin Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Ingo Molnar Cc: Jiri Olsa Cc: llvm@lists.linux.dev Cc: Mark Rutland Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Tom Rix Link: https://lore.kernel.org/r/20230105082609.344538-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Rename perf_include_dir to libbpf_include_dir

2022-11-04T14:45:36Z

As this is where we expect to find bpf/bpf_helpers.h, etc. This needs more work to make it follow LIBBPF_DYNAMIC=1 usage, i.e. when not using the system libbpf it should use the headers in the in-kernel sources libbpf in tools/lib/bpf. We need to do that anyway to avoid this mixup system libbpf and in-kernel files, so we'll get this sorted out that way. And this also may become moot as we move to using BPF skels for this feature. Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Raw augmented syscalls fix libbpf 1.0+ compatibility

2022-11-04T14:33:40Z

Don't use deprecated and now broken map style. Avoid use of tools/perf/include/bpf/bpf.h and use the more regular BPF headers. Committer notes: Add /usr/include to the include path so that bpf/bpf_helpers.h can be found, remove sys/socket.h, adding the sockaddr_storage definition, also remove stdbool.h, both were preventing building the augmented_raw_syscalls.c file with clang, revisit later. Testing it: Asking for syscalls that have string arguments: # perf trace -e ~acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c,string --max-events 10 0.000 thermald/1144 openat(dfd: CWD, filename: "/sys/class/powercap/intel-rapl/intel-rapl:0/intel-rapl:0:2/energy_uj", flags: RDONLY) = 13 0.158 thermald/1144 openat(dfd: CWD, filename: "/sys/class/powercap/intel-rapl/intel-rapl:0/energy_uj", flags: RDONLY) = 13 0.215 thermald/1144 openat(dfd: CWD, filename: "/sys/class/thermal/thermal_zone3/temp", flags: RDONLY) = 13 16.448 cgroupify/36478 openat(dfd: 4, filename: ".", flags: RDONLY|CLOEXEC|DIRECTORY|NONBLOCK) = 5 16.468 cgroupify/36478 newfstatat(dfd: 5, filename: "", statbuf: 0x7fffca5b4130, flag: 4096) = 0 16.473 systemd-oomd/972 openat(dfd: CWD, filename: "/proc/meminfo", flags: RDONLY|CLOEXEC) = 12 16.499 systemd-oomd/972 newfstatat(dfd: 12, filename: "", statbuf: 0x7ffd2bc73cc0, flag: 4096) = 0 16.516 abrt-dump-jour/1370 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 21 16.538 abrt-dump-jour/1370 newfstatat(dfd: 21, filename: "", statbuf: 0x7ffc651b8980, flag: 4096) = 0 16.540 abrt-dump-jour/1371 openat(dfd: CWD, filename: "/var/log/journal/d6a97235307247e09f13f326fb607e3c/system.journal", flags: RDONLY|CLOEXEC|NONBLOCK) = 21 # Networking syscalls: # perf trace -e ~acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c,sendto*,connect* --max-events 10 0.000 isc-net-0005/1206 connect(fd: 512, uservaddr: { .family: INET, port: 53, addr: 23.211.132.65 }, addrlen: 16) = 0 0.070 isc-net-0002/1203 connect(fd: 515, uservaddr: { .family: INET6, port: 53, addr: 2600:1401:2::43 }, addrlen: 28) = -1 ENETUNREACH (Network is unreachable) 0.031 isc-net-0006/1207 connect(fd: 513, uservaddr: { .family: INET6, port: 53, addr: 2600:1401:2::43 }, addrlen: 28) = -1 ENETUNREACH (Network is unreachable) 0.079 isc-net-0006/1207 sendto(fd: 3, buff: 0x7f73a40611b0, len: 106, flags: NOSIGNAL, addr: { .family: UNSPEC }, addr_len: NULL) = 106 0.180 isc-net-0006/1207 connect(fd: 519, uservaddr: { .family: INET6, port: 53, addr: 2600:1401:1::43 }, addrlen: 28) = -1 ENETUNREACH (Network is unreachable) 0.211 isc-net-0006/1207 sendto(fd: 3, buff: 0x7f73a4061230, len: 106, flags: NOSIGNAL, addr: { .family: UNSPEC }, addr_len: NULL) = 106 0.298 isc-net-0006/1207 connect(fd: 515, uservaddr: { .family: INET, port: 53, addr: 96.7.49.67 }, addrlen: 16) = 0 0.109 isc-net-0004/1205 connect(fd: 518, uservaddr: { .family: INET6, port: 53, addr: 2600:1401:2::43 }, addrlen: 28) = -1 ENETUNREACH (Network is unreachable) 0.164 isc-net-0002/1203 sendto(fd: 3, buff: 0x7f73ac064300, len: 107, flags: NOSIGNAL, addr: { .family: UNSPEC }, addr_len: NULL) = 107 0.247 isc-net-0002/1203 connect(fd: 522, uservaddr: { .family: INET6, port: 53, addr: 2600:1401:1::43 }, addrlen: 28) = -1 ENETUNREACH (Network is unreachable) # Signed-off-by: Ian Rogers Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20221103045437.163510-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Convert legacy map definition to BTF-defined

2022-08-01T17:43:13Z

The libbpf is switching off support for legacy map definitions [1], which will break the perf llvm tests. Moving the base source map definition to BTF-defined, so we need to use -g compile option for to add debug/BTF info. [1] https://lore.kernel.org/bpf/20220627211527.2245459-1-andrii@kernel.org/ Signed-off-by: Jiri Olsa Acked-by: Andrii Nakryiko Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20220704152721.352046-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix LLVM download hint link

2021-08-31T18:18:16Z

http://llvm.org/apt returns 404, it has moved to https://apt.llvm.org/ Signed-off-by: James Clark Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20210831145501.2135754-3-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix LLVM test failure when running in verbose mode

2021-08-31T18:17:45Z

A CI system might want to run all tests in verbose mode so that there is enough information to diagnose issues. This LLVM test is the only test that uses "-v" to signify to not skip the test if the preconditions aren't met (LLVM isn't installed). This means that running the test in verbose mode without LLVM installed causes a test failure. For consistency with the other tests, remove this verbose/skip check. An alternate solution would be to make _all_ tests not skip when run in verbose mode, but I don't think that would be intuitive. Also change the search_program() call to search_program_and_warn(). Previously the hint about installing LLVM was only printed by the actual test because this check was skipped in verbose mode. To maintain the old behaviour, the precondition check must also print the full warning. Previous output: $ ./perf test llvm 40: LLVM search and compile : 40.1: Basic BPF llvm compile : Skip $ ./perf test -v llvm 40: LLVM search and compile : 40.1: Basic BPF llvm compile : --- start --- test child forked, pid 2085835 ERROR: unable to find clang. Hint: Try to install latest clang/llvm to support BPF. Check your $PATH ... test child finished with -1 ---- end ---- LLVM search and compile subtest 1: FAILED! New output (non verbose mode is identical, verbose changes from fail to skip): $ ./perf test llvm 40: LLVM search and compile : 40.1: Basic BPF llvm compile : Skip $ ./perf test -v llvm 40: LLVM search and compile : 40.1: Basic BPF llvm compile : --- start --- test child forked, pid 2087680 ERROR: unable to find clang. Hint: Try to install latest clang/llvm to support BPF. Check your $PATH ... No clang, skip this test test child finished with -2 ---- end ---- LLVM search and compile subtest 1: Skip Signed-off-by: James Clark Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20210831145501.2135754-2-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Refactor LLVM test warning for missing binary

2021-08-31T18:17:07Z

The same warning is duplicated in two places so refactor it into a single function "search_program_and_warn". This will be used a third time in a later commit. Signed-off-by: James Clark Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20210831145501.2135754-1-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo

perf llvm: Return -ENOMEM when asprintf() fails

2021-07-01T19:14:37Z

Zhihao sent a patch but it made llvm__compile_bpf() return what asprintf() returns on error, which is just -1, but since this function returns -errno, fix it by returning -ENOMEM for this case instead. Fixes: cb76371441d098 ("perf llvm: Allow passing options to llc ...") Fixes: 5eab5a7ee032ac ("perf llvm: Display eBPF compiling command ...") Reported-by: Hulk Robot Reported-by: Zhihao Cheng Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Daniel Borkmann Cc: Ingo Molnar Cc: Jiri Olsa Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Yu Kuai Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20210609115945.2193194-1-chengzhihao1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo