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2023-08-15perf bpf examples: With no BPF events remove examplesIan Rogers1-27/+0
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 <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrii Nakryiko <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Brendan Gregg <[email protected]> Cc: Carsten Haitzler <[email protected]> Cc: Eduard Zingerman <[email protected]> Cc: Fangrui Song <[email protected]> Cc: He Kuang <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Kan Liang <[email protected]> Cc: Leo Yan <[email protected]> Cc: Madhavan Srinivasan <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Rob Herring <[email protected]> Cc: Tiezhu Yang <[email protected]> Cc: Tom Rix <[email protected]> Cc: Wang Nan <[email protected]> Cc: Wang ShaoBo <[email protected]> Cc: Yang Jihong <[email protected]> Cc: Yonghong Song <[email protected]> Cc: YueHaibing <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2022-11-04perf trace: hello fix libbpf 1.0+ compatibilityIan Rogers1-3/+21
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. Switch to raw_syscalls:sys_enter to avoid the evlist being empty and fixing generating output. Committer testing: # perf trace -e ~acme/git/perf/tools/perf/examples/bpf/hello.c --call-graph=dwarf --max-events 5 0.000 perf/206852 __bpf_stdout__(Hello, world) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) do_syscall_64 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe ([kernel.kallsyms]) __GI___sched_setaffinity_new (/usr/lib64/libc.so.6) 8.561 pipewire/2290 __bpf_stdout__(Hello, world) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) do_syscall_64 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe ([kernel.kallsyms]) __libc_read (/usr/lib64/libc.so.6) 8.571 pipewire/2290 __bpf_stdout__(Hello, world) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) do_syscall_64 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe ([kernel.kallsyms]) __GI___ioctl (/usr/lib64/libc.so.6) 8.586 pipewire/2290 __bpf_stdout__(Hello, world) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) do_syscall_64 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe ([kernel.kallsyms]) __GI___write (/usr/lib64/libc.so.6) 8.592 pipewire/2290 __bpf_stdout__(Hello, world) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) syscall_trace_enter.constprop.0 ([kernel.kallsyms]) do_syscall_64 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe ([kernel.kallsyms]) __timerfd_settime (/usr/lib64/libc.so.6) # Signed-off-by: Ian Rogers <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Leo Yan <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-08perf bpf: Add bpf/stdio.h wrapper to bpf_perf_event_output functionArnaldo Carvalho de Melo1-0/+9
That, together with the map __bpf_output__ that is already handled by 'perf trace' to print that event's contents as strings provides a debugging facility, to show it in use, print a simple string everytime the syscalls:sys_enter_openat() syscall tracepoint is hit: # cat tools/perf/examples/bpf/hello.c #include <stdio.h> int syscall_enter(openat)(void *args) { puts("Hello, world\n"); return 0; } license(GPL); # # perf trace -e openat,tools/perf/examples/bpf/hello.c cat /etc/passwd > /dev/null 0.016 ( ): __bpf_stdout__:Hello, world 0.018 ( 0.010 ms): cat/9079 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC) = 3 0.057 ( ): __bpf_stdout__:Hello, world 0.059 ( 0.011 ms): cat/9079 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC) = 3 0.417 ( ): __bpf_stdout__:Hello, world 0.419 ( 0.009 ms): cat/9079 openat(dfd: CWD, filename: /etc/passwd) = 3 # This is part of an ongoing experimentation on making eBPF scripts as consumed by perf to be as concise as possible and using familiar concepts such as stdio.h functions, that end up just wrapping the existing BPF functions, trying to hide as much boilerplate as possible while using just conventions and C preprocessor tricks. Cc: Adrian Hunter <[email protected]> Cc: David Ahern <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Wang Nan <[email protected]> Link: https://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>