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2023-08-15perf bpf examples: With no BPF events remove examplesIan Rogers
The examples were used to give demonstrations of BPF events but such functionality is now subsumed by using --filter with 'perf record' or the direct use of BPF skeletons. Signed-off-by: Ian Rogers <irogers@google.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: Andrii Nakryiko <andrii@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Carsten Haitzler <carsten.haitzler@arm.com> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Fangrui Song <maskray@google.com> Cc: He Kuang <hekuang@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Rob Herring <robh@kernel.org> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Cc: Tom Rix <trix@redhat.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: Wang ShaoBo <bobo.shaobowang@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yonghong Song <yhs@fb.com> Cc: YueHaibing <yuehaibing@huawei.com> Cc: bpf@vger.kernel.org Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230810184853.2860737-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-11-04perf trace: empty fix libbpf 1.0+ compatibilityIan Rogers
Avoid use of tools/perf/include/bpf/bpf.h and use the more regular BPF headers. Add raw_syscalls:sys_enter to avoid the evlist being empty. Committer testing: # time perf trace -e ~acme/git/perf/tools/perf/examples/bpf/empty.c sleep 5 real 0m5.697s user 0m0.217s sys 0m0.453s # I.e. it sets up everything successfully (use -v to see the details) and filters out all syscalls, then exits when the workload (sleep 5) finishes. Signed-off-by: Ian Rogers <irogers@google.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: Leo Yan <leo.yan@linaro.org> 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> Link: https://lore.kernel.org/r/20221103045437.163510-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-01-20perf: Use consistent include paths for libbpfToke Høiland-Jørgensen
Fix perf to include libbpf header files with the bpf/ prefix, to be consistent with external users of the library. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/157952560797.1683545.7685921032671386301.stgit@toke.dk
2018-05-15perf bpf: Add license(NAME) helperArnaldo Carvalho de Melo
To further reduce boilerplate. 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-vst6hj335s0ebxzqltes3nsc@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-05-15perf bpf: Add bpf.h to be used in eBPF proggiesArnaldo Carvalho de Melo
So, the first helper is the one shortening a variable/function section attribute, from, for instance: char _license[] __attribute__((section("license"), used)) = "GPL"; to: char _license[] SEC("license") = "GPL"; Convert empty.c to that and it becomes: # cat ~acme/lib/examples/perf/bpf/empty.c #include <bpf.h> char _license[] SEC("license") = "GPL"; int _version SEC("version") = LINUX_VERSION_CODE; # 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-zmeg52dlvy51rdlhyumfl5yf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-05-15perf bpf: Add 'examples' directoriesArnaldo Carvalho de Melo
The first one is the bare minimum that bpf infrastructure accepts before it expects actual events to be set up: $ cat tools/perf/examples/bpf/empty.c char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = LINUX_VERSION_CODE; $ If you remove that "version" line, then it will be refused with: # perf trace -e tools/perf/examples/bpf/empty.c event syntax error: 'tools/perf/examples/bpf/empty.c' \___ Failed to load tools/perf/examples/bpf/empty.c from source: 'version' section incorrect or lost (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf trace [<options>] [<command>] or: perf trace [<options>] -- <command> [<options>] or: perf trace record [<options>] [<command>] or: perf trace record [<options>] -- <command> [<options>] -e, --event <event> event/syscall selector. use 'perf list' to list available events # The next ones will, step by step, show simple filters, then the needs for headers will be made clear, it will be put in place and tested with new examples, rinse, repeat. Back to using this first one to test the perf+bpf infrastructure: If we run it will fail, as no functions are present connecting with, say, a tracepoint or a function using the kprobes or uprobes infrastructure: # perf trace -e tools/perf/examples/bpf/empty.c WARNING: event parser found nothing invalid or unsupported event: 'tools/perf/examples/bpf/empty.c' Run 'perf list' for a list of valid events Usage: perf trace [<options>] [<command>] or: perf trace [<options>] -- <command> [<options>] or: perf trace record [<options>] [<command>] or: perf trace record [<options>] -- <command> [<options>] -e, --event <event> event/syscall selector. use 'perf list' to list available events # But, if we set things up to dump the generated object file to a file, and do this after having run 'make install', still on the developer's $HOME directory: # cat ~/.perfconfig [llvm] dump-obj = true # # perf trace -e ~acme/lib/examples/perf/bpf/empty.c LLVM: dumping /home/acme/lib/examples/perf/bpf/empty.o WARNING: event parser found nothing invalid or unsupported event: '/home/acme/lib/examples/perf/bpf/empty.c' <SNIP> # We can look at the dumped object file: # ls -la ~acme/lib/examples/perf/bpf/empty.o -rw-r--r--. 1 root root 576 May 4 12:10 /home/acme/lib/examples/perf/bpf/empty.o # file ~acme/lib/examples/perf/bpf/empty.o /home/acme/lib/examples/perf/bpf/empty.o: ELF 64-bit LSB relocatable, *unknown arch 0xf7* version 1 (SYSV), not stripped # readelf -sw ~acme/lib/examples/perf/bpf/empty.o Symbol table '.symtab' contains 3 entries: Num: Value Size Type Bind Vis Ndx Name 0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND 1: 0000000000000000 0 NOTYPE GLOBAL DEFAULT 3 _license 2: 0000000000000000 0 NOTYPE GLOBAL DEFAULT 4 _version # # tools/bpf/bpftool/bpftool --pretty ~acme/lib/examples/perf/bpf/empty.o null # 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-y7dkhakejz3013o0w21n98xd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>