From 84c86ca12b2189df751eed7b2d67cb63bc8feda5 Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Wed, 14 Oct 2015 12:41:14 +0000 Subject: perf tools: Enable passing bpf object file to --event By introducing new rules in tools/perf/util/parse-events.[ly], this patch enables 'perf record --event bpf_file.o' to select events by an eBPF object file. It calls parse_events_load_bpf() to load that file, which uses bpf__prepare_load() and finally calls bpf_object__open() for the object files. After applying this patch, commands like: # perf record --event foo.o sleep become possible. However, at this point it is unable to link any useful things onto the evsel list because the creating of probe points and BPF program attaching have not been implemented. Before real events are possible to be extracted, to avoid perf report error because of empty evsel list, this patch link a dummy evsel. The dummy event related code will be removed when probing and extracting code is ready. Commiter notes: Using it: $ ls -la foo.o ls: cannot access foo.o: No such file or directory $ perf record --event foo.o sleep libbpf: failed to open foo.o: No such file or directory event syntax error: 'foo.o' \___ BPF object file 'foo.o' is invalid (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [] [] or: perf record [] -- [] -e, --event event selector. use 'perf list' to list available events $ $ file /tmp/build/perf/perf.o /tmp/build/perf/perf.o: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), not stripped $ perf record --event /tmp/build/perf/perf.o sleep libbpf: /tmp/build/perf/perf.o is not an eBPF object file event syntax error: '/tmp/build/perf/perf.o' \___ BPF object file '/tmp/build/perf/perf.o' is invalid (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [] [] or: perf record [] -- [] -e, --event event selector. use 'perf list' to list available events $ $ file /tmp/foo.o /tmp/foo.o: ELF 64-bit LSB relocatable, no machine, version 1 (SYSV), not stripped $ perf record --event /tmp/foo.o sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data ] $ perf evlist /tmp/foo.o $ perf evlist -v /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 $ So, type 1 is PERF_TYPE_SOFTWARE, config 0x9 is PERF_COUNT_SW_DUMMY, ok. $ perf report --stdio Error: The perf.data file has no samples! # To display the perf.data header info, please use --header/--header-only options. # $ Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1444826502-49291-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/perf.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'tools/perf/perf.c') diff --git a/tools/perf/perf.c b/tools/perf/perf.c index 543713422d14..3d4c7c09adea 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -15,6 +15,7 @@ #include "util/run-command.h" #include "util/parse-events.h" #include "util/parse-options.h" +#include "util/bpf-loader.h" #include "util/debug.h" #include #include @@ -385,6 +386,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv) status = p->fn(argc, argv, prefix); exit_browser(status); perf_env__exit(&perf_env); + bpf__clear(); if (status) return status & 0xff; -- cgit v1.2.3